Publish

574 files changed, 38627 insertions, 0 deletions

diff --git a/config/.gitignore b/config/.gitignore
new file mode 100644
index 00000000000..170b98b585f
--- /dev/null
+++ b/config/.gitignore
@@ -0,0 +1,4 @@
+/pom.xml.build
+/target
+Makefile
+Testing
diff --git a/config/CMakeLists.txt b/config/CMakeLists.txt
new file mode 100644
index 00000000000..b6e0f7de178
--- /dev/null
+++ b/config/CMakeLists.txt
@@ -0,0 +1,58 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_define_module(
+    DEPENDS
+    fastos
+    vespalib
+    staging_vespalib
+    vespalog
+    fnet
+
+    EXTERNAL_DEPENDS
+    lz4
+
+    LIBS
+    src/apps/configproxy-cmd
+    src/apps/getvespaconfig
+    src/apps/pingproxy
+    src/vespa/config
+    src/vespa/config/common
+    src/vespa/config/configgen
+    src/vespa/config/file
+    src/vespa/config/frt
+    src/vespa/config/helper
+    src/vespa/config/print
+    src/vespa/config/raw
+    src/vespa/config/retriever
+    src/vespa/config/set
+    src/vespa/config/subscription
+
+    APPS
+    src/tests/configfetcher
+    src/tests/print
+    src/tests/payload_converter
+    src/tests/api
+    src/tests/configholder
+    src/tests/unittest
+    src/tests/frtconnectionpool
+    src/tests/file_subscription
+    src/tests/legacysubscriber
+    src/tests/subscriber
+    src/tests/configagent
+    src/tests/getconfig
+    src/tests/configgen
+    src/tests/configmanager
+    src/tests/raw_subscription
+    src/tests/trace
+    src/tests/misc
+    src/tests/configformat
+    src/tests/frt
+    src/tests/configretriever
+    src/tests/functiontest
+    src/tests/configuri
+    src/tests/failover
+    src/tests/subscription
+    src/tests/configparser
+)
+
+vespa_install_script(src/apps/activate-application/activate-application.sh activate-application bin)
+vespa_install_script(src/apps/vespa-config/vespa-config.pl libexec/vespa)
diff --git a/config/OWNERS b/config/OWNERS
new file mode 100644
index 00000000000..7028eebe31a
--- /dev/null
+++ b/config/OWNERS
@@ -0,0 +1,2 @@
+musum
+arnej27959
diff --git a/config/doc/java/batchConfigurer.png b/config/doc/java/batchConfigurer.png
new file mode 100644
index 00000000000..18adf8663ba
--- /dev/null
+++ b/config/doc/java/batchConfigurer.png
diff --git a/config/doc/java/classes.vsd b/config/doc/java/classes.vsd
new file mode 100644
index 00000000000..9f5fa882790
--- /dev/null
+++ b/config/doc/java/classes.vsd
diff --git a/config/doc/java/client.png b/config/doc/java/client.png
new file mode 100644
index 00000000000..afd84114fa8
--- /dev/null
+++ b/config/doc/java/client.png
diff --git a/config/doc/java/client_nodes.png b/config/doc/java/client_nodes.png
new file mode 100644
index 00000000000..20f29fac093
--- /dev/null
+++ b/config/doc/java/client_nodes.png
diff --git a/config/doc/java/configHelper.png b/config/doc/java/configHelper.png
new file mode 100644
index 00000000000..ef553eee485
--- /dev/null
+++ b/config/doc/java/configHelper.png
diff --git a/config/doc/java/proxy.png b/config/doc/java/proxy.png
new file mode 100644
index 00000000000..91c767f0e4a
--- /dev/null
+++ b/config/doc/java/proxy.png
diff --git a/config/doc/java/proxy_error_configured.png b/config/doc/java/proxy_error_configured.png
new file mode 100644
index 00000000000..279a7dac3bb
--- /dev/null
+++ b/config/doc/java/proxy_error_configured.png
diff --git a/config/doc/java/proxy_error_subscribe.png b/config/doc/java/proxy_error_subscribe.png
new file mode 100644
index 00000000000..37b9f1d66a2
--- /dev/null
+++ b/config/doc/java/proxy_error_subscribe.png
diff --git a/config/doc/java/proxy_interaction.png b/config/doc/java/proxy_interaction.png
new file mode 100644
index 00000000000..e79dafcd48c
--- /dev/null
+++ b/config/doc/java/proxy_interaction.png
diff --git a/config/doc/java/proxy_reload.png b/config/doc/java/proxy_reload.png
new file mode 100644
index 00000000000..0103643f9ab
--- /dev/null
+++ b/config/doc/java/proxy_reload.png
diff --git a/config/doc/library-design.txt b/config/doc/library-design.txt
new file mode 100644
index 00000000000..cbea6e283b2
--- /dev/null
+++ b/config/doc/library-design.txt
@@ -0,0 +1,90 @@
+# Config library
+
+## Introduction
+
+The config library is used by Vespa applications to subscribe to
+configuration from the Vespa config system.
+
+The low-level <a href="protocol-design.html">config protocol</a> is
+used for communication between the application and a config source.
+
+The config library has Java and C++ implementations.
+Implementation-specific issues are noted at the end of this document.
+
+
+## Config API
+
+The config API that are used by clients will be mostly unchanged from
+previous versions of Vespa.
+
+## Config subscriptions
+
+A client application generates config code based on config definition
+files as described in the user documentation.
+An application will implement a Subscriber
+interface with a *configure()* callback and call the generated code's
+*subscribe()* method to get a particular config.  *subscribe()* will
+not return until *configure()* has been called and the application is
+configured, or some fatal error occured which will lead to an
+exception being thrown.
+
+The *subscribe()* call will add the client to the list of subscribers
+for this config and create a new Subscription object if there does not
+exist one already for this config.
+
+The Subscription object is the central object for communication
+between the client and the config source.  When such an object is
+created it will lead to a *getConfig()* (see <a
+href="protocol-design.html">config protocol</a> documentation) call.
+The Subscription object will make sure that *getConfig()* is called
+and waiting for a response throughout the application's lifetime.
+That way, new config will be discovered when this method call returns,
+which it will do immediately if the subscribed config changes at the
+config source.  At the same time, since the server timeout defined in
+the protocol can be set to a high number, generating unnecessary
+network traffic by polling frequently is avoided.
+
+When the *getConfig()* call returns, a new *getConfig()* call is
+scheduled for execution at a later time.  If the response was
+successful, this will happen immediately.  If there was an error the
+delay until the call will be performed depends on the number of times
+since last succesful execution, and if the application has been
+configured already or not (we want to try more aggrressively if the
+aplication has not been configured).  There is a maximum delay defined
+for this scheduling.
+
+
+## Config sources 
+
+A config source can either be a config server or a config proxy.  The
+default behavior for applications is to use one local config source, a
+config proxy on localhost, port 19090.  It is possible to use one or
+more other sources too, by setting the environment variable
+VESPA\_CONFIG\_SOURCES (a comma-separated list of hostnames, with
+optional port number, like _foo,bar_ or _foo:1234,bar:2345_).
+
+### Selecting config source
+
+The config library selects a config source when requesting config
+(performing the *getConfig()* method call) in a way that makes all
+config requests from one paricular Internet host address use the same
+config source (unless it is suspended, i.e. down, inaccessible etc.).
+
+A config source can experience both transient and fatal errors. The
+config library (and config proxy) will when configured with several
+sources suspend a source for a period of time, where the suspension
+time is based on the type of error and the number of times the error
+has happened.  A suspended config source will not be considered when
+doing a new selection of config source, except if it is the only
+source configured.
+
+As an example, a transient failure that happens 5 times will lead to
+the config source being suspended for 10 seconds the first time it
+happens, 20 seconds the next time and so on.  A more permanent error
+will lead to similar behavior, except the supension times will be
+higher.  There is a maximum delay for both types of errors.
+
+
+## C++ library
+
+## Java library
diff --git a/config/doc/protocol-design.txt b/config/doc/protocol-design.txt
new file mode 100644
index 00000000000..ba7fd7d7538
--- /dev/null
+++ b/config/doc/protocol-design.txt
@@ -0,0 +1,85 @@
+# Config protocol
+
+## Introduction
+
+This document describes the low-level config protocol based on fnet/rpc.
+
+## Overview of the protocol
+
+The protocol is stateless and similiar to HTTP GET and other REST
+APIs, but implemented as remote procedure calls (RPC).  A client
+performs a method call get(), and a server returns a response if the
+config has changed since the last time get() was called, or waits a
+specified time before returning (unless the config changes before the
+timeout is reached, in case it returns immediately). Since the
+protocol is stateless, it is easy to use more than one config server
+to serve config.  It is also possible to use a (cacheing) proxy
+between client and server.
+
+The figure below shows a simplified view of how an application *App*
+uses the config library API to subscribe to a config.  The protocol is
+shown as *get()* call and *ret()* responses.  Optionally, a proxy can 
+be used between client and the server.
+
+<img src='rpc-config-protocol.png' alt='RPC config protocol' />
+
+In the figure above, the first parameter *X* is a designator for the
+config to get, the second parameter is a generation number and the
+third parameter *T* is a server timeout.
+
+The server (or proxy, if the client is using one) will generate a
+response immediately if the config *X* has another (higher) generation
+number than the one requested.  If not, the server will create a timer
+with timeout *T* and respond when the timer expires or the requested
+config changes, whatever comes first.
+
+If the response was generated because the config changed, the config
+payload will be included in the response and a change flag set to mark
+that the response contains changed config.  Else the change flag will
+not be set (and no config payload included in the response).
+
+The client timeout (how long the client waits for an answer before
+giving up), should be longer than the server timeout *T*.
+
+
+## Implementation
+
+The implementation of get() is an RPC method called getConfig() with
+the following signature:
+
+	  getConfig(String configId, String defName, String defVersion, String defMD5, String configMD5, long timeout)
+
+and the parameters:
+
+* *configId* - config id
+* *defName* - config definition name
+* *defVersion* - config definition version
+* *defMD5* - config definition md5sum
+* *configMD5* - config md5sum (the md5sum of the config payload)
+* *timeout* - server timeout
+
+The fifth parameter, the config md5sum, is used instead of a
+generation number.  If a config is found, the md5sum of the config
+payload will be returned in the response, so that subsequent calls to
+getConfig() will use this new md5sum as *configMD5*.  When getting
+config the first time, this parameter will be an empty string.
+
+
+The return parameters are:
+
+	   String configId, String defName, String defVersion, String defMD5, String configMD5, int changed, long generation, String payload)
+
+with the first 5 parameters being the same as the one in the
+request. The rest are:
+
+* *changed* - a flag the will have a value of 1 if there is a config
+   *payload* in the response, or 0 else.
+* *generation* - generation when the config was last changed (in milliseconds since 1970).
+* *payload* - config payload.  Will only have a value if *changed* is 1.
+
+The payload is the same as in the previous version of this protocol.
+
+The *generation* parameter can be used to check how old the config
+is. In case of getting a new payload (*changed* is 1, this can be used
+to check that the config returned has a newer timstamp thatn the last
+returned from a config source (this
diff --git a/config/pom.xml b/config/pom.xml
new file mode 100755
index 00000000000..4dd4e1a37fd
--- /dev/null
+++ b/config/pom.xml
@@ -0,0 +1,210 @@
+<?xml version="1.0"?>
+<!-- Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root. -->
+<project xmlns="http://maven.apache.org/POM/4.0.0" xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
+         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/maven-v4_0_0.xsd">
+  <modelVersion>4.0.0</modelVersion>
+  <parent>
+    <groupId>com.yahoo.vespa</groupId>
+    <artifactId>parent</artifactId>
+    <version>6-SNAPSHOT</version>
+    <relativePath>../parent/pom.xml</relativePath>
+  </parent>
+  <artifactId>config</artifactId>
+  <packaging>container-plugin</packaging>
+  <version>6-SNAPSHOT</version>
+  <dependencies>
+    <dependency>
+      <groupId>junit</groupId>
+      <artifactId>junit</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.google.code.findbugs</groupId>
+      <artifactId>annotations</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>com.yahoo.vespa</groupId>
+      <artifactId>annotations</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>com.yahoo.vespa</groupId>
+      <artifactId>config-lib</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>com.yahoo.vespa</groupId>
+      <artifactId>configgen</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>com.yahoo.vespa</groupId>
+      <artifactId>jrt</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>com.yahoo.vespa</groupId>
+      <artifactId>vespajlib</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>com.yahoo.vespa</groupId>
+      <artifactId>yolean</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>com.yahoo.vespa</groupId>
+      <artifactId>vespalog</artifactId>
+      <version>${project.version}</version>
+    </dependency>
+    <dependency>
+      <groupId>org.hamcrest</groupId>
+      <artifactId>hamcrest-core</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>uk.co.datumedge</groupId>
+      <artifactId>hamcrest-json</artifactId>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.google.guava</groupId>
+      <artifactId>guava</artifactId>
+      <version>13.0.1</version>
+      <scope>provided</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.google.guava</groupId>
+      <artifactId>guava-testlib</artifactId>
+      <version>17.0</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.yahoo.vespa</groupId>
+      <artifactId>testutil</artifactId>
+      <version>${project.version}</version>
+      <scope>test</scope>
+    </dependency>
+    <dependency>
+      <groupId>com.fasterxml.jackson.core</groupId>
+      <artifactId>jackson-core</artifactId>
+    </dependency>
+    <dependency>
+      <groupId>net.jpountz.lz4</groupId>
+      <artifactId>lz4</artifactId>
+    </dependency>
+  </dependencies>
+  <profiles>
+    <profile>
+      <id>stress-tests</id>
+      <build>
+        <plugins>
+          <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-surefire-plugin</artifactId>
+            <configuration>
+              <includes>
+                <include>**/ConfigserverSubscriptionTest.java</include>
+                <include>**/ProxyServerTest.java</include>
+              </includes>
+            </configuration>
+          </plugin>
+        </plugins>
+      </build>
+    </profile>
+    <profile>
+      <id>factory-tests</id>
+      <build>
+        <plugins>
+          <plugin>
+            <groupId>org.apache.maven.plugins</groupId>
+            <artifactId>maven-surefire-plugin</artifactId>
+            <configuration>
+              <excludes>
+                <exclude>**/ConfigserverSubscriptionTest.java</exclude>
+                <exclude>**/ProxyServerTest.java</exclude>
+              </excludes>
+            </configuration>
+          </plugin>
+        </plugins>
+      </build>
+    </profile>
+  </profiles>
+  <build>
+    <plugins>
+      <plugin>
+        <groupId>org.codehaus.mojo</groupId>
+        <artifactId>exec-maven-plugin</artifactId>
+        <executions>
+          <execution>
+            <id>generate-vtag</id>
+            <phase>generate-sources</phase>
+            <goals>
+              <goal>java</goal>
+            </goals>
+            <configuration>
+              <mainClass>com.yahoo.vespa.VersionTagger</mainClass>
+              <arguments>
+                <argument>${project.basedir}/../dist/vtag.map</argument>
+                <argument>com.yahoo.vespa.config</argument>
+                <argument>${project.build.directory}/generated-sources/vtag</argument>
+              </arguments>
+              <sourceRoot>${project.build.directory}/generated-sources/vtag</sourceRoot>
+              <classpathScope>compile</classpathScope>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+      <plugin>
+        <groupId>com.yahoo.vespa</groupId>
+        <artifactId>config-class-plugin</artifactId>
+        <version>${project.version}</version>
+        <executions>
+          <execution>
+            <id>configgen-test-defs</id>
+            <phase>generate-test-sources</phase>
+            <goals>
+              <goal>config-gen</goal>
+            </goals>
+            <configuration>
+              <defFilesDirectories>src/test/resources/configs/def-files</defFilesDirectories>
+              <outputDirectory>target/generated-test-sources/vespa-configgen-plugin</outputDirectory>
+              <testConfig>true</testConfig>
+              <requireNamespace>false</requireNamespace>
+            </configuration>
+          </execution>
+        </executions>
+      </plugin>
+      <plugin>
+        <groupId>com.yahoo.vespa</groupId>
+        <artifactId>bundle-plugin</artifactId>
+        <extensions>true</extensions>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-compiler-plugin</artifactId>
+        <configuration>
+          <compilerArgs>
+            <arg>-Xlint:all</arg>
+            <arg>-Werror</arg>
+          </compilerArgs>
+        </configuration>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-surefire-plugin</artifactId>
+        <configuration>
+          <redirectTestOutputToFile>${test.hide}</redirectTestOutputToFile>
+          <forkMode>once</forkMode>
+        </configuration>
+      </plugin>
+      <plugin>
+        <groupId>org.apache.maven.plugins</groupId>
+        <artifactId>maven-install-plugin</artifactId>
+        <configuration>
+          <updateReleaseInfo>true</updateReleaseInfo>
+        </configuration>
+      </plugin>
+    </plugins>
+  </build>
+</project>
diff --git a/config/src/.gitignore b/config/src/.gitignore
new file mode 100644
index 00000000000..528c8f7183d
--- /dev/null
+++ b/config/src/.gitignore
@@ -0,0 +1,4 @@
+/Makefile.ini
+/config.mak
+/config_command.sh
+/project.dsw
diff --git a/config/src/Doxyfile b/config/src/Doxyfile
new file mode 100644
index 00000000000..19c31437cdb
--- /dev/null
+++ b/config/src/Doxyfile
@@ -0,0 +1,1255 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+# Doxyfile 1.4.7
+
+# This file describes the settings to be used by the documentation system
+# doxygen (www.doxygen.org) for a project
+#
+# All text after a hash (#) is considered a comment and will be ignored
+# The format is:
+#       TAG = value [value, ...]
+# For lists items can also be appended using:
+#       TAG += value [value, ...]
+# Values that contain spaces should be placed between quotes (" ")
+
+#---------------------------------------------------------------------------
+# Project related configuration options
+#---------------------------------------------------------------------------
+
+# The PROJECT_NAME tag is a single word (or a sequence of words surrounded 
+# by quotes) that should identify the project.
+
+PROJECT_NAME           = cloudconfig
+
+# The PROJECT_NUMBER tag can be used to enter a project or revision number. 
+# This could be handy for archiving the generated documentation or 
+# if some version control system is used.
+
+PROJECT_NUMBER         = 
+
+# The OUTPUT_DIRECTORY tag is used to specify the (relative or absolute) 
+# base path where the generated documentation will be put. 
+# If a relative path is entered, it will be relative to the location 
+# where doxygen was started. If left blank the current directory will be used.
+
+OUTPUT_DIRECTORY       = ../../doc
+
+# If the CREATE_SUBDIRS tag is set to YES, then doxygen will create 
+# 4096 sub-directories (in 2 levels) under the output directory of each output 
+# format and will distribute the generated files over these directories. 
+# Enabling this option can be useful when feeding doxygen a huge amount of 
+# source files, where putting all generated files in the same directory would 
+# otherwise cause performance problems for the file system.
+
+CREATE_SUBDIRS         = NO
+
+# The OUTPUT_LANGUAGE tag is used to specify the language in which all 
+# documentation generated by doxygen is written. Doxygen will use this 
+# information to generate all constant output in the proper language. 
+# The default language is English, other supported languages are: 
+# Brazilian, Catalan, Chinese, Chinese-Traditional, Croatian, Czech, Danish, 
+# Dutch, Finnish, French, German, Greek, Hungarian, Italian, Japanese, 
+# Japanese-en (Japanese with English messages), Korean, Korean-en, Norwegian, 
+# Polish, Portuguese, Romanian, Russian, Serbian, Slovak, Slovene, Spanish, 
+# Swedish, and Ukrainian.
+
+OUTPUT_LANGUAGE        = English
+
+# This tag can be used to specify the encoding used in the generated output. 
+# The encoding is not always determined by the language that is chosen, 
+# but also whether or not the output is meant for Windows or non-Windows users. 
+# In case there is a difference, setting the USE_WINDOWS_ENCODING tag to YES 
+# forces the Windows encoding (this is the default for the Windows binary), 
+# whereas setting the tag to NO uses a Unix-style encoding (the default for 
+# all platforms other than Windows).
+
+USE_WINDOWS_ENCODING   = NO
+
+# If the BRIEF_MEMBER_DESC tag is set to YES (the default) Doxygen will 
+# include brief member descriptions after the members that are listed in 
+# the file and class documentation (similar to JavaDoc). 
+# Set to NO to disable this.
+
+BRIEF_MEMBER_DESC      = YES
+
+# If the REPEAT_BRIEF tag is set to YES (the default) Doxygen will prepend 
+# the brief description of a member or function before the detailed description. 
+# Note: if both HIDE_UNDOC_MEMBERS and BRIEF_MEMBER_DESC are set to NO, the 
+# brief descriptions will be completely suppressed.
+
+REPEAT_BRIEF           = YES
+
+# This tag implements a quasi-intelligent brief description abbreviator 
+# that is used to form the text in various listings. Each string 
+# in this list, if found as the leading text of the brief description, will be 
+# stripped from the text and the result after processing the whole list, is 
+# used as the annotated text. Otherwise, the brief description is used as-is. 
+# If left blank, the following values are used ("$name" is automatically 
+# replaced with the name of the entity): "The $name class" "The $name widget" 
+# "The $name file" "is" "provides" "specifies" "contains" 
+# "represents" "a" "an" "the"
+
+ABBREVIATE_BRIEF       = 
+
+# If the ALWAYS_DETAILED_SEC and REPEAT_BRIEF tags are both set to YES then 
+# Doxygen will generate a detailed section even if there is only a brief 
+# description.
+
+ALWAYS_DETAILED_SEC    = NO
+
+# If the INLINE_INHERITED_MEMB tag is set to YES, doxygen will show all 
+# inherited members of a class in the documentation of that class as if those 
+# members were ordinary class members. Constructors, destructors and assignment 
+# operators of the base classes will not be shown.
+
+INLINE_INHERITED_MEMB  = NO
+
+# If the FULL_PATH_NAMES tag is set to YES then Doxygen will prepend the full 
+# path before files name in the file list and in the header files. If set 
+# to NO the shortest path that makes the file name unique will be used.
+
+FULL_PATH_NAMES        = YES
+
+# If the FULL_PATH_NAMES tag is set to YES then the STRIP_FROM_PATH tag 
+# can be used to strip a user-defined part of the path. Stripping is 
+# only done if one of the specified strings matches the left-hand part of 
+# the path. The tag can be used to show relative paths in the file list. 
+# If left blank the directory from which doxygen is run is used as the 
+# path to strip.
+
+STRIP_FROM_PATH        = 
+
+# The STRIP_FROM_INC_PATH tag can be used to strip a user-defined part of 
+# the path mentioned in the documentation of a class, which tells 
+# the reader which header file to include in order to use a class. 
+# If left blank only the name of the header file containing the class 
+# definition is used. Otherwise one should specify the include paths that 
+# are normally passed to the compiler using the -I flag.
+
+STRIP_FROM_INC_PATH    = 
+
+# If the SHORT_NAMES tag is set to YES, doxygen will generate much shorter 
+# (but less readable) file names. This can be useful is your file systems 
+# doesn't support long names like on DOS, Mac, or CD-ROM.
+
+SHORT_NAMES            = NO
+
+# If the JAVADOC_AUTOBRIEF tag is set to YES then Doxygen 
+# will interpret the first line (until the first dot) of a JavaDoc-style 
+# comment as the brief description. If set to NO, the JavaDoc 
+# comments will behave just like the Qt-style comments (thus requiring an 
+# explicit @brief command for a brief description.
+
+JAVADOC_AUTOBRIEF      = YES
+
+# The MULTILINE_CPP_IS_BRIEF tag can be set to YES to make Doxygen 
+# treat a multi-line C++ special comment block (i.e. a block of //! or /// 
+# comments) as a brief description. This used to be the default behaviour. 
+# The new default is to treat a multi-line C++ comment block as a detailed 
+# description. Set this tag to YES if you prefer the old behaviour instead.
+
+MULTILINE_CPP_IS_BRIEF = NO
+
+# If the DETAILS_AT_TOP tag is set to YES then Doxygen 
+# will output the detailed description near the top, like JavaDoc.
+# If set to NO, the detailed description appears after the member 
+# documentation.
+
+DETAILS_AT_TOP         = NO
+
+# If the INHERIT_DOCS tag is set to YES (the default) then an undocumented 
+# member inherits the documentation from any documented member that it 
+# re-implements.
+
+INHERIT_DOCS           = YES
+
+# If the SEPARATE_MEMBER_PAGES tag is set to YES, then doxygen will produce 
+# a new page for each member. If set to NO, the documentation of a member will 
+# be part of the file/class/namespace that contains it.
+
+SEPARATE_MEMBER_PAGES  = NO
+
+# The TAB_SIZE tag can be used to set the number of spaces in a tab. 
+# Doxygen uses this value to replace tabs by spaces in code fragments.
+
+TAB_SIZE               = 4
+
+# This tag can be used to specify a number of aliases that acts 
+# as commands in the documentation. An alias has the form "name=value". 
+# For example adding "sideeffect=\par Side Effects:\n" will allow you to 
+# put the command \sideeffect (or @sideeffect) in the documentation, which 
+# will result in a user-defined paragraph with heading "Side Effects:". 
+# You can put \n's in the value part of an alias to insert newlines.
+
+ALIASES                = 
+
+# Set the OPTIMIZE_OUTPUT_FOR_C tag to YES if your project consists of C 
+# sources only. Doxygen will then generate output that is more tailored for C. 
+# For instance, some of the names that are used will be different. The list 
+# of all members will be omitted, etc.
+
+OPTIMIZE_OUTPUT_FOR_C  = NO
+
+# Set the OPTIMIZE_OUTPUT_JAVA tag to YES if your project consists of Java 
+# sources only. Doxygen will then generate output that is more tailored for Java. 
+# For instance, namespaces will be presented as packages, qualified scopes 
+# will look different, etc.
+
+OPTIMIZE_OUTPUT_JAVA   = NO
+
+# If you use STL classes (i.e. std::string, std::vector, etc.) but do not want to 
+# include (a tag file for) the STL sources as input, then you should 
+# set this tag to YES in order to let doxygen match functions declarations and 
+# definitions whose arguments contain STL classes (e.g. func(std::string); v.s. 
+# func(std::string) {}). This also make the inheritance and collaboration 
+# diagrams that involve STL classes more complete and accurate.
+
+BUILTIN_STL_SUPPORT    = NO
+
+# If member grouping is used in the documentation and the DISTRIBUTE_GROUP_DOC 
+# tag is set to YES, then doxygen will reuse the documentation of the first 
+# member in the group (if any) for the other members of the group. By default 
+# all members of a group must be documented explicitly.
+
+DISTRIBUTE_GROUP_DOC   = NO
+
+# Set the SUBGROUPING tag to YES (the default) to allow class member groups of 
+# the same type (for instance a group of public functions) to be put as a 
+# subgroup of that type (e.g. under the Public Functions section). Set it to 
+# NO to prevent subgrouping. Alternatively, this can be done per class using 
+# the \nosubgrouping command.
+
+SUBGROUPING            = YES
+
+#---------------------------------------------------------------------------
+# Build related configuration options
+#---------------------------------------------------------------------------
+
+# If the EXTRACT_ALL tag is set to YES doxygen will assume all entities in 
+# documentation are documented, even if no documentation was available. 
+# Private class members and static file members will be hidden unless 
+# the EXTRACT_PRIVATE and EXTRACT_STATIC tags are set to YES
+
+EXTRACT_ALL            = NO
+
+# If the EXTRACT_PRIVATE tag is set to YES all private members of a class 
+# will be included in the documentation.
+
+EXTRACT_PRIVATE        = NO
+
+# If the EXTRACT_STATIC tag is set to YES all static members of a file 
+# will be included in the documentation.
+
+EXTRACT_STATIC         = NO
+
+# If the EXTRACT_LOCAL_CLASSES tag is set to YES classes (and structs) 
+# defined locally in source files will be included in the documentation. 
+# If set to NO only classes defined in header files are included.
+
+EXTRACT_LOCAL_CLASSES  = YES
+
+# This flag is only useful for Objective-C code. When set to YES local 
+# methods, which are defined in the implementation section but not in 
+# the interface are included in the documentation. 
+# If set to NO (the default) only methods in the interface are included.
+
+EXTRACT_LOCAL_METHODS  = NO
+
+# If the HIDE_UNDOC_MEMBERS tag is set to YES, Doxygen will hide all 
+# undocumented members of documented classes, files or namespaces. 
+# If set to NO (the default) these members will be included in the 
+# various overviews, but no documentation section is generated. 
+# This option has no effect if EXTRACT_ALL is enabled.
+
+HIDE_UNDOC_MEMBERS     = NO
+
+# If the HIDE_UNDOC_CLASSES tag is set to YES, Doxygen will hide all 
+# undocumented classes that are normally visible in the class hierarchy. 
+# If set to NO (the default) these classes will be included in the various 
+# overviews. This option has no effect if EXTRACT_ALL is enabled.
+
+HIDE_UNDOC_CLASSES     = NO
+
+# If the HIDE_FRIEND_COMPOUNDS tag is set to YES, Doxygen will hide all 
+# friend (class|struct|union) declarations. 
+# If set to NO (the default) these declarations will be included in the 
+# documentation.
+
+HIDE_FRIEND_COMPOUNDS  = NO
+
+# If the HIDE_IN_BODY_DOCS tag is set to YES, Doxygen will hide any 
+# documentation blocks found inside the body of a function. 
+# If set to NO (the default) these blocks will be appended to the 
+# function's detailed documentation block.
+
+HIDE_IN_BODY_DOCS      = NO
+
+# The INTERNAL_DOCS tag determines if documentation 
+# that is typed after a \internal command is included. If the tag is set 
+# to NO (the default) then the documentation will be excluded. 
+# Set it to YES to include the internal documentation.
+
+INTERNAL_DOCS          = NO
+
+# If the CASE_SENSE_NAMES tag is set to NO then Doxygen will only generate 
+# file names in lower-case letters. If set to YES upper-case letters are also 
+# allowed. This is useful if you have classes or files whose names only differ 
+# in case and if your file system supports case sensitive file names. Windows 
+# and Mac users are advised to set this option to NO.
+
+CASE_SENSE_NAMES       = YES
+
+# If the HIDE_SCOPE_NAMES tag is set to NO (the default) then Doxygen 
+# will show members with their full class and namespace scopes in the 
+# documentation. If set to YES the scope will be hidden.
+
+HIDE_SCOPE_NAMES       = NO
+
+# If the SHOW_INCLUDE_FILES tag is set to YES (the default) then Doxygen 
+# will put a list of the files that are included by a file in the documentation 
+# of that file.
+
+SHOW_INCLUDE_FILES     = YES
+
+# If the INLINE_INFO tag is set to YES (the default) then a tag [inline] 
+# is inserted in the documentation for inline members.
+
+INLINE_INFO            = YES
+
+# If the SORT_MEMBER_DOCS tag is set to YES (the default) then doxygen 
+# will sort the (detailed) documentation of file and class members 
+# alphabetically by member name. If set to NO the members will appear in 
+# declaration order.
+
+SORT_MEMBER_DOCS       = YES
+
+# If the SORT_BRIEF_DOCS tag is set to YES then doxygen will sort the 
+# brief documentation of file, namespace and class members alphabetically 
+# by member name. If set to NO (the default) the members will appear in 
+# declaration order.
+
+SORT_BRIEF_DOCS        = NO
+
+# If the SORT_BY_SCOPE_NAME tag is set to YES, the class list will be 
+# sorted by fully-qualified names, including namespaces. If set to 
+# NO (the default), the class list will be sorted only by class name, 
+# not including the namespace part. 
+# Note: This option is not very useful if HIDE_SCOPE_NAMES is set to YES.
+# Note: This option applies only to the class list, not to the 
+# alphabetical list.
+
+SORT_BY_SCOPE_NAME     = NO
+
+# The GENERATE_TODOLIST tag can be used to enable (YES) or 
+# disable (NO) the todo list. This list is created by putting \todo 
+# commands in the documentation.
+
+GENERATE_TODOLIST      = YES
+
+# The GENERATE_TESTLIST tag can be used to enable (YES) or 
+# disable (NO) the test list. This list is created by putting \test 
+# commands in the documentation.
+
+GENERATE_TESTLIST      = YES
+
+# The GENERATE_BUGLIST tag can be used to enable (YES) or 
+# disable (NO) the bug list. This list is created by putting \bug 
+# commands in the documentation.
+
+GENERATE_BUGLIST       = YES
+
+# The GENERATE_DEPRECATEDLIST tag can be used to enable (YES) or 
+# disable (NO) the deprecated list. This list is created by putting 
+# \deprecated commands in the documentation.
+
+GENERATE_DEPRECATEDLIST= YES
+
+# The ENABLED_SECTIONS tag can be used to enable conditional 
+# documentation sections, marked by \if sectionname ... \endif.
+
+ENABLED_SECTIONS       = 
+
+# The MAX_INITIALIZER_LINES tag determines the maximum number of lines 
+# the initial value of a variable or define consists of for it to appear in 
+# the documentation. If the initializer consists of more lines than specified 
+# here it will be hidden. Use a value of 0 to hide initializers completely. 
+# The appearance of the initializer of individual variables and defines in the 
+# documentation can be controlled using \showinitializer or \hideinitializer 
+# command in the documentation regardless of this setting.
+
+MAX_INITIALIZER_LINES  = 30
+
+# Set the SHOW_USED_FILES tag to NO to disable the list of files generated 
+# at the bottom of the documentation of classes and structs. If set to YES the 
+# list will mention the files that were used to generate the documentation.
+
+SHOW_USED_FILES        = YES
+
+# If the sources in your project are distributed over multiple directories 
+# then setting the SHOW_DIRECTORIES tag to YES will show the directory hierarchy 
+# in the documentation. The default is NO.
+
+SHOW_DIRECTORIES       = YES
+
+# The FILE_VERSION_FILTER tag can be used to specify a program or script that 
+# doxygen should invoke to get the current version for each file (typically from the 
+# version control system). Doxygen will invoke the program by executing (via 
+# popen()) the command <command> <input-file>, where <command> is the value of 
+# the FILE_VERSION_FILTER tag, and <input-file> is the name of an input file 
+# provided by doxygen. Whatever the program writes to standard output 
+# is used as the file version. See the manual for examples.
+
+FILE_VERSION_FILTER    = 
+
+#---------------------------------------------------------------------------
+# configuration options related to warning and progress messages
+#---------------------------------------------------------------------------
+
+# The QUIET tag can be used to turn on/off the messages that are generated 
+# by doxygen. Possible values are YES and NO. If left blank NO is used.
+
+QUIET                  = NO
+
+# The WARNINGS tag can be used to turn on/off the warning messages that are 
+# generated by doxygen. Possible values are YES and NO. If left blank 
+# NO is used.
+
+WARNINGS               = YES
+
+# If WARN_IF_UNDOCUMENTED is set to YES, then doxygen will generate warnings 
+# for undocumented members. If EXTRACT_ALL is set to YES then this flag will 
+# automatically be disabled.
+
+WARN_IF_UNDOCUMENTED   = YES
+
+# If WARN_IF_DOC_ERROR is set to YES, doxygen will generate warnings for 
+# potential errors in the documentation, such as not documenting some 
+# parameters in a documented function, or documenting parameters that 
+# don't exist or using markup commands wrongly.
+
+WARN_IF_DOC_ERROR      = YES
+
+# This WARN_NO_PARAMDOC option can be abled to get warnings for 
+# functions that are documented, but have no documentation for their parameters 
+# or return value. If set to NO (the default) doxygen will only warn about 
+# wrong or incomplete parameter documentation, but not about the absence of 
+# documentation.
+
+WARN_NO_PARAMDOC       = NO
+
+# The WARN_FORMAT tag determines the format of the warning messages that 
+# doxygen can produce. The string should contain the $file, $line, and $text 
+# tags, which will be replaced by the file and line number from which the 
+# warning originated and the warning text. Optionally the format may contain 
+# $version, which will be replaced by the version of the file (if it could 
+# be obtained via FILE_VERSION_FILTER)
+
+WARN_FORMAT            = "$file:$line: $text"
+
+# The WARN_LOGFILE tag can be used to specify a file to which warning 
+# and error messages should be written. If left blank the output is written 
+# to stderr.
+
+WARN_LOGFILE           = 
+
+#---------------------------------------------------------------------------
+# configuration options related to the input files
+#---------------------------------------------------------------------------
+
+# The INPUT tag can be used to specify the files and/or directories that contain 
+# documented source files. You may enter file names like "myfile.cpp" or 
+# directories like "/usr/src/myproject". Separate the files or directories 
+# with spaces.
+
+INPUT                  = config
+
+# If the value of the INPUT tag contains directories, you can use the 
+# FILE_PATTERNS tag to specify one or more wildcard pattern (like *.cpp 
+# and *.h) to filter out the source-files in the directories. If left 
+# blank the following patterns are tested: 
+# *.c *.cc *.cxx *.cpp *.c++ *.java *.ii *.ixx *.ipp *.i++ *.inl *.h *.hh *.hxx 
+# *.hpp *.h++ *.idl *.odl *.cs *.php *.php3 *.inc *.m *.mm *.py
+
+FILE_PATTERNS          = *.h \
+                         *.hpp \
+                         *.cpp
+
+# The RECURSIVE tag can be used to turn specify whether or not subdirectories 
+# should be searched for input files as well. Possible values are YES and NO. 
+# If left blank NO is used.
+
+RECURSIVE              = YES 
+
+# The EXCLUDE tag can be used to specify files and/or directories that should 
+# excluded from the INPUT source files. This way you can easily exclude a 
+# subdirectory from a directory tree whose root is specified with the INPUT tag.
+
+EXCLUDE                =
+
+# The EXCLUDE_SYMLINKS tag can be used select whether or not files or 
+# directories that are symbolic links (a Unix filesystem feature) are excluded 
+# from the input.
+
+EXCLUDE_SYMLINKS       = NO
+
+# If the value of the INPUT tag contains directories, you can use the 
+# EXCLUDE_PATTERNS tag to specify one or more wildcard patterns to exclude 
+# certain files from those directories. Note that the wildcards are matched 
+# against the file with absolute path, so to exclude all test directories 
+# for example use the pattern */test/*
+
+EXCLUDE_PATTERNS       = 
+
+# The EXAMPLE_PATH tag can be used to specify one or more files or 
+# directories that contain example code fragments that are included (see 
+# the \include command).
+
+EXAMPLE_PATH           = 
+
+# If the value of the EXAMPLE_PATH tag contains directories, you can use the 
+# EXAMPLE_PATTERNS tag to specify one or more wildcard pattern (like *.cpp 
+# and *.h) to filter out the source-files in the directories. If left 
+# blank all files are included.
+
+EXAMPLE_PATTERNS       = 
+
+# If the EXAMPLE_RECURSIVE tag is set to YES then subdirectories will be 
+# searched for input files to be used with the \include or \dontinclude 
+# commands irrespective of the value of the RECURSIVE tag. 
+# Possible values are YES and NO. If left blank NO is used.
+
+EXAMPLE_RECURSIVE      = NO
+
+# The IMAGE_PATH tag can be used to specify one or more files or 
+# directories that contain image that are included in the documentation (see 
+# the \image command).
+
+IMAGE_PATH             = 
+
+# The INPUT_FILTER tag can be used to specify a program that doxygen should 
+# invoke to filter for each input file. Doxygen will invoke the filter program 
+# by executing (via popen()) the command <filter> <input-file>, where <filter> 
+# is the value of the INPUT_FILTER tag, and <input-file> is the name of an 
+# input file. Doxygen will then use the output that the filter program writes 
+# to standard output.  If FILTER_PATTERNS is specified, this tag will be 
+# ignored.
+
+INPUT_FILTER           = 
+
+# The FILTER_PATTERNS tag can be used to specify filters on a per file pattern 
+# basis.  Doxygen will compare the file name with each pattern and apply the 
+# filter if there is a match.  The filters are a list of the form: 
+# pattern=filter (like *.cpp=my_cpp_filter). See INPUT_FILTER for further 
+# info on how filters are used. If FILTER_PATTERNS is empty, INPUT_FILTER 
+# is applied to all files.
+
+FILTER_PATTERNS        = 
+
+# If the FILTER_SOURCE_FILES tag is set to YES, the input filter (if set using 
+# INPUT_FILTER) will be used to filter the input files when producing source 
+# files to browse (i.e. when SOURCE_BROWSER is set to YES).
+
+FILTER_SOURCE_FILES    = NO
+
+#---------------------------------------------------------------------------
+# configuration options related to source browsing
+#---------------------------------------------------------------------------
+
+# If the SOURCE_BROWSER tag is set to YES then a list of source files will 
+# be generated. Documented entities will be cross-referenced with these sources. 
+# Note: To get rid of all source code in the generated output, make sure also 
+# VERBATIM_HEADERS is set to NO.
+
+SOURCE_BROWSER         = NO
+
+# Setting the INLINE_SOURCES tag to YES will include the body 
+# of functions and classes directly in the documentation.
+
+INLINE_SOURCES         = NO
+
+# Setting the STRIP_CODE_COMMENTS tag to YES (the default) will instruct 
+# doxygen to hide any special comment blocks from generated source code 
+# fragments. Normal C and C++ comments will always remain visible.
+
+STRIP_CODE_COMMENTS    = YES
+
+# If the REFERENCED_BY_RELATION tag is set to YES (the default) 
+# then for each documented function all documented 
+# functions referencing it will be listed.
+
+REFERENCED_BY_RELATION = YES
+
+# If the REFERENCES_RELATION tag is set to YES (the default) 
+# then for each documented function all documented entities 
+# called/used by that function will be listed.
+
+REFERENCES_RELATION    = YES
+
+# If the REFERENCES_LINK_SOURCE tag is set to YES (the default)
+# and SOURCE_BROWSER tag is set to YES, then the hyperlinks from
+# functions in REFERENCES_RELATION and REFERENCED_BY_RELATION lists will
+# link to the source code.  Otherwise they will link to the documentstion.
+
+REFERENCES_LINK_SOURCE = YES
+
+# If the USE_HTAGS tag is set to YES then the references to source code 
+# will point to the HTML generated by the htags(1) tool instead of doxygen 
+# built-in source browser. The htags tool is part of GNU's global source 
+# tagging system (see http://www.gnu.org/software/global/global.html). You 
+# will need version 4.8.6 or higher.
+
+USE_HTAGS              = NO
+
+# If the VERBATIM_HEADERS tag is set to YES (the default) then Doxygen 
+# will generate a verbatim copy of the header file for each class for 
+# which an include is specified. Set to NO to disable this.
+
+VERBATIM_HEADERS       = YES
+
+#---------------------------------------------------------------------------
+# configuration options related to the alphabetical class index
+#---------------------------------------------------------------------------
+
+# If the ALPHABETICAL_INDEX tag is set to YES, an alphabetical index 
+# of all compounds will be generated. Enable this if the project 
+# contains a lot of classes, structs, unions or interfaces.
+
+ALPHABETICAL_INDEX     = NO
+
+# If the alphabetical index is enabled (see ALPHABETICAL_INDEX) then 
+# the COLS_IN_ALPHA_INDEX tag can be used to specify the number of columns 
+# in which this list will be split (can be a number in the range [1..20])
+
+COLS_IN_ALPHA_INDEX    = 5
+
+# In case all classes in a project start with a common prefix, all 
+# classes will be put under the same header in the alphabetical index. 
+# The IGNORE_PREFIX tag can be used to specify one or more prefixes that 
+# should be ignored while generating the index headers.
+
+IGNORE_PREFIX          = 
+
+#---------------------------------------------------------------------------
+# configuration options related to the HTML output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_HTML tag is set to YES (the default) Doxygen will 
+# generate HTML output.
+
+GENERATE_HTML          = YES
+
+# The HTML_OUTPUT tag is used to specify where the HTML docs will be put. 
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
+# put in front of it. If left blank `html' will be used as the default path.
+
+HTML_OUTPUT            = html
+
+# The HTML_FILE_EXTENSION tag can be used to specify the file extension for 
+# each generated HTML page (for example: .htm,.php,.asp). If it is left blank 
+# doxygen will generate files with .html extension.
+
+HTML_FILE_EXTENSION    = .html
+
+# The HTML_HEADER tag can be used to specify a personal HTML header for 
+# each generated HTML page. If it is left blank doxygen will generate a 
+# standard header.
+
+HTML_HEADER            = 
+
+# The HTML_FOOTER tag can be used to specify a personal HTML footer for 
+# each generated HTML page. If it is left blank doxygen will generate a 
+# standard footer.
+
+HTML_FOOTER            = 
+
+# The HTML_STYLESHEET tag can be used to specify a user-defined cascading 
+# style sheet that is used by each HTML page. It can be used to 
+# fine-tune the look of the HTML output. If the tag is left blank doxygen 
+# will generate a default style sheet. Note that doxygen will try to copy 
+# the style sheet file to the HTML output directory, so don't put your own 
+# stylesheet in the HTML output directory as well, or it will be erased!
+
+HTML_STYLESHEET        = 
+
+# If the HTML_ALIGN_MEMBERS tag is set to YES, the members of classes, 
+# files or namespaces will be aligned in HTML using tables. If set to 
+# NO a bullet list will be used.
+
+HTML_ALIGN_MEMBERS     = YES
+
+# If the GENERATE_HTMLHELP tag is set to YES, additional index files 
+# will be generated that can be used as input for tools like the 
+# Microsoft HTML help workshop to generate a compressed HTML help file (.chm) 
+# of the generated HTML documentation.
+
+GENERATE_HTMLHELP      = NO
+
+# If the GENERATE_HTMLHELP tag is set to YES, the CHM_FILE tag can 
+# be used to specify the file name of the resulting .chm file. You 
+# can add a path in front of the file if the result should not be 
+# written to the html output directory.
+
+CHM_FILE               = 
+
+# If the GENERATE_HTMLHELP tag is set to YES, the HHC_LOCATION tag can 
+# be used to specify the location (absolute path including file name) of 
+# the HTML help compiler (hhc.exe). If non-empty doxygen will try to run 
+# the HTML help compiler on the generated index.hhp.
+
+HHC_LOCATION           = 
+
+# If the GENERATE_HTMLHELP tag is set to YES, the GENERATE_CHI flag 
+# controls if a separate .chi index file is generated (YES) or that 
+# it should be included in the master .chm file (NO).
+
+GENERATE_CHI           = NO
+
+# If the GENERATE_HTMLHELP tag is set to YES, the BINARY_TOC flag 
+# controls whether a binary table of contents is generated (YES) or a 
+# normal table of contents (NO) in the .chm file.
+
+BINARY_TOC             = NO
+
+# The TOC_EXPAND flag can be set to YES to add extra items for group members 
+# to the contents of the HTML help documentation and to the tree view.
+
+TOC_EXPAND             = NO
+
+# The DISABLE_INDEX tag can be used to turn on/off the condensed index at 
+# top of each HTML page. The value NO (the default) enables the index and 
+# the value YES disables it.
+
+DISABLE_INDEX          = NO
+
+# This tag can be used to set the number of enum values (range [1..20]) 
+# that doxygen will group on one line in the generated HTML documentation.
+
+ENUM_VALUES_PER_LINE   = 4
+
+# If the GENERATE_TREEVIEW tag is set to YES, a side panel will be
+# generated containing a tree-like index structure (just like the one that 
+# is generated for HTML Help). For this to work a browser that supports 
+# JavaScript, DHTML, CSS and frames is required (for instance Mozilla 1.0+, 
+# Netscape 6.0+, Internet explorer 5.0+, or Konqueror). Windows users are 
+# probably better off using the HTML help feature.
+
+GENERATE_TREEVIEW      = NO
+
+# If the treeview is enabled (see GENERATE_TREEVIEW) then this tag can be 
+# used to set the initial width (in pixels) of the frame in which the tree 
+# is shown.
+
+TREEVIEW_WIDTH         = 250
+
+#---------------------------------------------------------------------------
+# configuration options related to the LaTeX output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_LATEX tag is set to YES (the default) Doxygen will 
+# generate Latex output.
+
+GENERATE_LATEX         = NO
+
+# The LATEX_OUTPUT tag is used to specify where the LaTeX docs will be put. 
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
+# put in front of it. If left blank `latex' will be used as the default path.
+
+LATEX_OUTPUT           = latex
+
+# The LATEX_CMD_NAME tag can be used to specify the LaTeX command name to be 
+# invoked. If left blank `latex' will be used as the default command name.
+
+LATEX_CMD_NAME         = latex
+
+# The MAKEINDEX_CMD_NAME tag can be used to specify the command name to 
+# generate index for LaTeX. If left blank `makeindex' will be used as the 
+# default command name.
+
+MAKEINDEX_CMD_NAME     = makeindex
+
+# If the COMPACT_LATEX tag is set to YES Doxygen generates more compact 
+# LaTeX documents. This may be useful for small projects and may help to 
+# save some trees in general.
+
+COMPACT_LATEX          = NO
+
+# The PAPER_TYPE tag can be used to set the paper type that is used 
+# by the printer. Possible values are: a4, a4wide, letter, legal and 
+# executive. If left blank a4wide will be used.
+
+PAPER_TYPE             = a4wide
+
+# The EXTRA_PACKAGES tag can be to specify one or more names of LaTeX 
+# packages that should be included in the LaTeX output.
+
+EXTRA_PACKAGES         = 
+
+# The LATEX_HEADER tag can be used to specify a personal LaTeX header for 
+# the generated latex document. The header should contain everything until 
+# the first chapter. If it is left blank doxygen will generate a 
+# standard header. Notice: only use this tag if you know what you are doing!
+
+LATEX_HEADER           = 
+
+# If the PDF_HYPERLINKS tag is set to YES, the LaTeX that is generated 
+# is prepared for conversion to pdf (using ps2pdf). The pdf file will 
+# contain links (just like the HTML output) instead of page references 
+# This makes the output suitable for online browsing using a pdf viewer.
+
+PDF_HYPERLINKS         = NO
+
+# If the USE_PDFLATEX tag is set to YES, pdflatex will be used instead of 
+# plain latex in the generated Makefile. Set this option to YES to get a 
+# higher quality PDF documentation.
+
+USE_PDFLATEX           = NO
+
+# If the LATEX_BATCHMODE tag is set to YES, doxygen will add the \\batchmode. 
+# command to the generated LaTeX files. This will instruct LaTeX to keep 
+# running if errors occur, instead of asking the user for help. 
+# This option is also used when generating formulas in HTML.
+
+LATEX_BATCHMODE        = NO
+
+# If LATEX_HIDE_INDICES is set to YES then doxygen will not 
+# include the index chapters (such as File Index, Compound Index, etc.) 
+# in the output.
+
+LATEX_HIDE_INDICES     = NO
+
+#---------------------------------------------------------------------------
+# configuration options related to the RTF output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_RTF tag is set to YES Doxygen will generate RTF output 
+# The RTF output is optimized for Word 97 and may not look very pretty with 
+# other RTF readers or editors.
+
+GENERATE_RTF           = NO
+
+# The RTF_OUTPUT tag is used to specify where the RTF docs will be put. 
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
+# put in front of it. If left blank `rtf' will be used as the default path.
+
+RTF_OUTPUT             = rtf
+
+# If the COMPACT_RTF tag is set to YES Doxygen generates more compact 
+# RTF documents. This may be useful for small projects and may help to 
+# save some trees in general.
+
+COMPACT_RTF            = NO
+
+# If the RTF_HYPERLINKS tag is set to YES, the RTF that is generated 
+# will contain hyperlink fields. The RTF file will 
+# contain links (just like the HTML output) instead of page references. 
+# This makes the output suitable for online browsing using WORD or other 
+# programs which support those fields. 
+# Note: wordpad (write) and others do not support links.
+
+RTF_HYPERLINKS         = NO
+
+# Load stylesheet definitions from file. Syntax is similar to doxygen's 
+# config file, i.e. a series of assignments. You only have to provide 
+# replacements, missing definitions are set to their default value.
+
+RTF_STYLESHEET_FILE    = 
+
+# Set optional variables used in the generation of an rtf document. 
+# Syntax is similar to doxygen's config file.
+
+RTF_EXTENSIONS_FILE    = 
+
+#---------------------------------------------------------------------------
+# configuration options related to the man page output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_MAN tag is set to YES (the default) Doxygen will 
+# generate man pages
+
+GENERATE_MAN           = NO
+
+# The MAN_OUTPUT tag is used to specify where the man pages will be put. 
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
+# put in front of it. If left blank `man' will be used as the default path.
+
+MAN_OUTPUT             = man
+
+# The MAN_EXTENSION tag determines the extension that is added to 
+# the generated man pages (default is the subroutine's section .3)
+
+MAN_EXTENSION          = .3
+
+# If the MAN_LINKS tag is set to YES and Doxygen generates man output, 
+# then it will generate one additional man file for each entity 
+# documented in the real man page(s). These additional files 
+# only source the real man page, but without them the man command 
+# would be unable to find the correct page. The default is NO.
+
+MAN_LINKS              = NO
+
+#---------------------------------------------------------------------------
+# configuration options related to the XML output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_XML tag is set to YES Doxygen will 
+# generate an XML file that captures the structure of 
+# the code including all documentation.
+
+GENERATE_XML           = NO
+
+# The XML_OUTPUT tag is used to specify where the XML pages will be put. 
+# If a relative path is entered the value of OUTPUT_DIRECTORY will be 
+# put in front of it. If left blank `xml' will be used as the default path.
+
+XML_OUTPUT             = xml
+
+# The XML_SCHEMA tag can be used to specify an XML schema, 
+# which can be used by a validating XML parser to check the 
+# syntax of the XML files.
+
+XML_SCHEMA             = 
+
+# The XML_DTD tag can be used to specify an XML DTD, 
+# which can be used by a validating XML parser to check the 
+# syntax of the XML files.
+
+XML_DTD                = 
+
+# If the XML_PROGRAMLISTING tag is set to YES Doxygen will 
+# dump the program listings (including syntax highlighting 
+# and cross-referencing information) to the XML output. Note that 
+# enabling this will significantly increase the size of the XML output.
+
+XML_PROGRAMLISTING     = YES
+
+#---------------------------------------------------------------------------
+# configuration options for the AutoGen Definitions output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_AUTOGEN_DEF tag is set to YES Doxygen will 
+# generate an AutoGen Definitions (see autogen.sf.net) file 
+# that captures the structure of the code including all 
+# documentation. Note that this feature is still experimental 
+# and incomplete at the moment.
+
+GENERATE_AUTOGEN_DEF   = NO
+
+#---------------------------------------------------------------------------
+# configuration options related to the Perl module output
+#---------------------------------------------------------------------------
+
+# If the GENERATE_PERLMOD tag is set to YES Doxygen will 
+# generate a Perl module file that captures the structure of 
+# the code including all documentation. Note that this 
+# feature is still experimental and incomplete at the 
+# moment.
+
+GENERATE_PERLMOD       = NO
+
+# If the PERLMOD_LATEX tag is set to YES Doxygen will generate 
+# the necessary Makefile rules, Perl scripts and LaTeX code to be able 
+# to generate PDF and DVI output from the Perl module output.
+
+PERLMOD_LATEX          = NO
+
+# If the PERLMOD_PRETTY tag is set to YES the Perl module output will be 
+# nicely formatted so it can be parsed by a human reader.  This is useful 
+# if you want to understand what is going on.  On the other hand, if this 
+# tag is set to NO the size of the Perl module output will be much smaller 
+# and Perl will parse it just the same.
+
+PERLMOD_PRETTY         = YES
+
+# The names of the make variables in the generated doxyrules.make file 
+# are prefixed with the string contained in PERLMOD_MAKEVAR_PREFIX. 
+# This is useful so different doxyrules.make files included by the same 
+# Makefile don't overwrite each other's variables.
+
+PERLMOD_MAKEVAR_PREFIX = 
+
+#---------------------------------------------------------------------------
+# Configuration options related to the preprocessor   
+#---------------------------------------------------------------------------
+
+# If the ENABLE_PREPROCESSING tag is set to YES (the default) Doxygen will 
+# evaluate all C-preprocessor directives found in the sources and include 
+# files.
+
+ENABLE_PREPROCESSING   = YES
+
+# If the MACRO_EXPANSION tag is set to YES Doxygen will expand all macro 
+# names in the source code. If set to NO (the default) only conditional 
+# compilation will be performed. Macro expansion can be done in a controlled 
+# way by setting EXPAND_ONLY_PREDEF to YES.
+
+MACRO_EXPANSION        = NO
+
+# If the EXPAND_ONLY_PREDEF and MACRO_EXPANSION tags are both set to YES 
+# then the macro expansion is limited to the macros specified with the 
+# PREDEFINED and EXPAND_AS_DEFINED tags.
+
+EXPAND_ONLY_PREDEF     = NO
+
+# If the SEARCH_INCLUDES tag is set to YES (the default) the includes files 
+# in the INCLUDE_PATH (see below) will be search if a #include is found.
+
+SEARCH_INCLUDES        = YES
+
+# The INCLUDE_PATH tag can be used to specify one or more directories that 
+# contain include files that are not input files but should be processed by 
+# the preprocessor.
+
+INCLUDE_PATH           = 
+
+# You can use the INCLUDE_FILE_PATTERNS tag to specify one or more wildcard 
+# patterns (like *.h and *.hpp) to filter out the header-files in the 
+# directories. If left blank, the patterns specified with FILE_PATTERNS will 
+# be used.
+
+INCLUDE_FILE_PATTERNS  = 
+
+# The PREDEFINED tag can be used to specify one or more macro names that 
+# are defined before the preprocessor is started (similar to the -D option of 
+# gcc). The argument of the tag is a list of macros of the form: name 
+# or name=definition (no spaces). If the definition and the = are 
+# omitted =1 is assumed. To prevent a macro definition from being 
+# undefined via #undef or recursively expanded use the := operator 
+# instead of the = operator.
+
+PREDEFINED             = IAM_DOXYGEN
+
+# If the MACRO_EXPANSION and EXPAND_ONLY_PREDEF tags are set to YES then 
+# this tag can be used to specify a list of macro names that should be expanded. 
+# The macro definition that is found in the sources will be used. 
+# Use the PREDEFINED tag if you want to use a different macro definition.
+
+EXPAND_AS_DEFINED      = 
+
+# If the SKIP_FUNCTION_MACROS tag is set to YES (the default) then 
+# doxygen's preprocessor will remove all function-like macros that are alone 
+# on a line, have an all uppercase name, and do not end with a semicolon. Such 
+# function macros are typically used for boiler-plate code, and will confuse 
+# the parser if not removed.
+
+SKIP_FUNCTION_MACROS   = YES
+
+#---------------------------------------------------------------------------
+# Configuration::additions related to external references   
+#---------------------------------------------------------------------------
+
+# The TAGFILES option can be used to specify one or more tagfiles. 
+# Optionally an initial location of the external documentation 
+# can be added for each tagfile. The format of a tag file without 
+# this location is as follows: 
+#   TAGFILES = file1 file2 ... 
+# Adding location for the tag files is done as follows: 
+#   TAGFILES = file1=loc1 "file2 = loc2" ... 
+# where "loc1" and "loc2" can be relative or absolute paths or 
+# URLs. If a location is present for each tag, the installdox tool 
+# does not have to be run to correct the links.
+# Note that each tag file must have a unique name
+# (where the name does NOT include the path)
+# If a tag file is not located in the directory in which doxygen 
+# is run, you must also specify the path to the tagfile here.
+
+TAGFILES               = 
+
+# When a file name is specified after GENERATE_TAGFILE, doxygen will create 
+# a tag file that is based on the input files it reads.
+
+GENERATE_TAGFILE       = 
+
+# If the ALLEXTERNALS tag is set to YES all external classes will be listed 
+# in the class index. If set to NO only the inherited external classes 
+# will be listed.
+
+ALLEXTERNALS           = NO
+
+# If the EXTERNAL_GROUPS tag is set to YES all external groups will be listed 
+# in the modules index. If set to NO, only the current project's groups will 
+# be listed.
+
+EXTERNAL_GROUPS        = YES
+
+# The PERL_PATH should be the absolute path and name of the perl script 
+# interpreter (i.e. the result of `which perl').
+
+PERL_PATH              = /usr/bin/perl
+
+#---------------------------------------------------------------------------
+# Configuration options related to the dot tool   
+#---------------------------------------------------------------------------
+
+# If the CLASS_DIAGRAMS tag is set to YES (the default) Doxygen will 
+# generate a inheritance diagram (in HTML, RTF and LaTeX) for classes with base 
+# or super classes. Setting the tag to NO turns the diagrams off. Note that 
+# this option is superseded by the HAVE_DOT option below. This is only a 
+# fallback. It is recommended to install and use dot, since it yields more 
+# powerful graphs.
+
+CLASS_DIAGRAMS         = YES
+
+# If set to YES, the inheritance and collaboration graphs will hide 
+# inheritance and usage relations if the target is undocumented 
+# or is not a class.
+
+HIDE_UNDOC_RELATIONS   = YES
+
+# If you set the HAVE_DOT tag to YES then doxygen will assume the dot tool is 
+# available from the path. This tool is part of Graphviz, a graph visualization 
+# toolkit from AT&T and Lucent Bell Labs. The other options in this section 
+# have no effect if this option is set to NO (the default)
+
+HAVE_DOT               = NO
+
+# If the CLASS_GRAPH and HAVE_DOT tags are set to YES then doxygen 
+# will generate a graph for each documented class showing the direct and 
+# indirect inheritance relations. Setting this tag to YES will force the 
+# the CLASS_DIAGRAMS tag to NO.
+
+CLASS_GRAPH            = YES
+
+# If the COLLABORATION_GRAPH and HAVE_DOT tags are set to YES then doxygen 
+# will generate a graph for each documented class showing the direct and 
+# indirect implementation dependencies (inheritance, containment, and 
+# class references variables) of the class with other documented classes.
+
+COLLABORATION_GRAPH    = YES
+
+# If the GROUP_GRAPHS and HAVE_DOT tags are set to YES then doxygen 
+# will generate a graph for groups, showing the direct groups dependencies
+
+GROUP_GRAPHS           = YES
+
+# If the UML_LOOK tag is set to YES doxygen will generate inheritance and 
+# collaboration diagrams in a style similar to the OMG's Unified Modeling 
+# Language.
+
+UML_LOOK               = NO
+
+# If set to YES, the inheritance and collaboration graphs will show the 
+# relations between templates and their instances.
+
+TEMPLATE_RELATIONS     = NO
+
+# If the ENABLE_PREPROCESSING, SEARCH_INCLUDES, INCLUDE_GRAPH, and HAVE_DOT 
+# tags are set to YES then doxygen will generate a graph for each documented 
+# file showing the direct and indirect include dependencies of the file with 
+# other documented files.
+
+INCLUDE_GRAPH          = YES
+
+# If the ENABLE_PREPROCESSING, SEARCH_INCLUDES, INCLUDED_BY_GRAPH, and 
+# HAVE_DOT tags are set to YES then doxygen will generate a graph for each 
+# documented header file showing the documented files that directly or 
+# indirectly include this file.
+
+INCLUDED_BY_GRAPH      = YES
+
+# If the CALL_GRAPH and HAVE_DOT tags are set to YES then doxygen will 
+# generate a call dependency graph for every global function or class method. 
+# Note that enabling this option will significantly increase the time of a run. 
+# So in most cases it will be better to enable call graphs for selected 
+# functions only using the \callgraph command.
+
+CALL_GRAPH             = NO
+
+# If the CALLER_GRAPH and HAVE_DOT tags are set to YES then doxygen will 
+# generate a caller dependency graph for every global function or class method. 
+# Note that enabling this option will significantly increase the time of a run. 
+# So in most cases it will be better to enable caller graphs for selected 
+# functions only using the \callergraph command.
+
+CALLER_GRAPH           = NO
+
+# If the GRAPHICAL_HIERARCHY and HAVE_DOT tags are set to YES then doxygen 
+# will graphical hierarchy of all classes instead of a textual one.
+
+GRAPHICAL_HIERARCHY    = YES
+
+# If the DIRECTORY_GRAPH, SHOW_DIRECTORIES and HAVE_DOT tags are set to YES 
+# then doxygen will show the dependencies a directory has on other directories 
+# in a graphical way. The dependency relations are determined by the #include
+# relations between the files in the directories.
+
+DIRECTORY_GRAPH        = YES
+
+# The DOT_IMAGE_FORMAT tag can be used to set the image format of the images 
+# generated by dot. Possible values are png, jpg, or gif
+# If left blank png will be used.
+
+DOT_IMAGE_FORMAT       = png
+
+# The tag DOT_PATH can be used to specify the path where the dot tool can be 
+# found. If left blank, it is assumed the dot tool can be found in the path.
+
+DOT_PATH               = 
+
+# The DOTFILE_DIRS tag can be used to specify one or more directories that 
+# contain dot files that are included in the documentation (see the 
+# \dotfile command).
+
+DOTFILE_DIRS           = 
+
+# The MAX_DOT_GRAPH_WIDTH tag can be used to set the maximum allowed width 
+# (in pixels) of the graphs generated by dot. If a graph becomes larger than 
+# this value, doxygen will try to truncate the graph, so that it fits within 
+# the specified constraint. Beware that most browsers cannot cope with very 
+# large images.
+
+MAX_DOT_GRAPH_WIDTH    = 1024
+
+# The MAX_DOT_GRAPH_HEIGHT tag can be used to set the maximum allows height 
+# (in pixels) of the graphs generated by dot. If a graph becomes larger than 
+# this value, doxygen will try to truncate the graph, so that it fits within 
+# the specified constraint. Beware that most browsers cannot cope with very 
+# large images.
+
+MAX_DOT_GRAPH_HEIGHT   = 1024
+
+# The MAX_DOT_GRAPH_DEPTH tag can be used to set the maximum depth of the 
+# graphs generated by dot. A depth value of 3 means that only nodes reachable 
+# from the root by following a path via at most 3 edges will be shown. Nodes 
+# that lay further from the root node will be omitted. Note that setting this 
+# option to 1 or 2 may greatly reduce the computation time needed for large 
+# code bases. Also note that a graph may be further truncated if the graph's 
+# image dimensions are not sufficient to fit the graph (see MAX_DOT_GRAPH_WIDTH 
+# and MAX_DOT_GRAPH_HEIGHT). If 0 is used for the depth value (the default), 
+# the graph is not depth-constrained.
+
+MAX_DOT_GRAPH_DEPTH    = 0
+
+# Set the DOT_TRANSPARENT tag to YES to generate images with a transparent 
+# background. This is disabled by default, which results in a white background. 
+# Warning: Depending on the platform used, enabling this option may lead to 
+# badly anti-aliased labels on the edges of a graph (i.e. they become hard to 
+# read).
+
+DOT_TRANSPARENT        = NO
+
+# Set the DOT_MULTI_TARGETS tag to YES allow dot to generate multiple output 
+# files in one run (i.e. multiple -o and -T options on the command line). This 
+# makes dot run faster, but since only newer versions of dot (>1.8.10) 
+# support this, this feature is disabled by default.
+
+DOT_MULTI_TARGETS      = NO
+
+# If the GENERATE_LEGEND tag is set to YES (the default) Doxygen will 
+# generate a legend page explaining the meaning of the various boxes and 
+# arrows in the dot generated graphs.
+
+GENERATE_LEGEND        = YES
+
+# If the DOT_CLEANUP tag is set to YES (the default) Doxygen will 
+# remove the intermediate dot files that are used to generate 
+# the various graphs.
+
+DOT_CLEANUP            = YES
+
+#---------------------------------------------------------------------------
+# Configuration::additions related to the search engine   
+#---------------------------------------------------------------------------
+
+# The SEARCHENGINE tag specifies whether or not a search engine should be 
+# used. If set to NO the values of all tags below this one will be ignored.
+
+SEARCHENGINE           = NO
diff --git a/config/src/apps/activate-application/activate-application.sh b/config/src/apps/activate-application/activate-application.sh
new file mode 100644
index 00000000000..82da8a1ab53
--- /dev/null
+++ b/config/src/apps/activate-application/activate-application.sh
@@ -0,0 +1,79 @@
+#!/bin/sh
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+# BEGIN environment bootstrap section
+# Do not edit between here and END as this section should stay identical in all scripts
+
+findpath () {
+    myname=${0}
+    mypath=${myname%/*}
+    myname=${myname##*/}
+    if [ "$mypath" ] && [ -d "$mypath" ]; then
+        return
+    fi
+    mypath=$(pwd)
+    if [ -f "${mypath}/${myname}" ]; then
+        return
+    fi
+    echo "FATAL: Could not figure out the path where $myname lives from $0"
+    exit 1
+}
+
+COMMON_ENV=libexec/vespa/common-env.sh
+
+source_common_env () {
+    if [ "$VESPA_HOME" ] && [ -d "$VESPA_HOME" ]; then
+        # ensure it ends with "/" :
+        VESPA_HOME=${VESPA_HOME%/}/
+        export VESPA_HOME
+        common_env=$VESPA_HOME/$COMMON_ENV
+        if [ -f "$common_env" ]; then
+            . $common_env
+            return
+        fi
+    fi
+    return 1
+}
+
+findroot () {
+    source_common_env && return
+    if [ "$VESPA_HOME" ]; then
+        echo "FATAL: bad VESPA_HOME value '$VESPA_HOME'"
+        exit 1
+    fi
+    if [ "$ROOT" ] && [ -d "$ROOT" ]; then
+        VESPA_HOME="$ROOT"
+        source_common_env && return
+    fi
+    findpath
+    while [ "$mypath" ]; do
+        VESPA_HOME=${mypath}
+        source_common_env && return
+        mypath=${mypath%/*}
+    done
+    echo "FATAL: missing VESPA_HOME environment variable"
+    echo "Could not locate $COMMON_ENV anywhere"
+    exit 1
+}
+
+findroot
+
+# END environment bootstrap section
+
+ROOT=$VESPA_HOME
+
+if [ "-f" == "$1" ] ; then
+    $ROOT/bin/deploy activate
+else
+    STATUS=$($ROOT/bin/vespa-status-filedistribution)
+    if [ $? -eq 0 ] ; then
+       $ROOT/bin/deploy activate
+    else
+       echo "$STATUS"
+       echo
+       echo "Files are currently being distributed."
+       echo "If you want to see the status, call 'vespa-status-filedistribution'."
+       echo "Otherwise, call 'activate-application -f' to activate the application now; the file transfers will continue in the background."
+       exit 1
+    fi
+fi
diff --git a/config/src/apps/configproxy-cmd/.gitignore b/config/src/apps/configproxy-cmd/.gitignore
new file mode 100644
index 00000000000..e39ac4f0c99
--- /dev/null
+++ b/config/src/apps/configproxy-cmd/.gitignore
@@ -0,0 +1,3 @@
+/.depend
+/Makefile
+/configproxy-cmd
diff --git a/config/src/apps/configproxy-cmd/CMakeLists.txt b/config/src/apps/configproxy-cmd/CMakeLists.txt
new file mode 100644
index 00000000000..17e941cde08
--- /dev/null
+++ b/config/src/apps/configproxy-cmd/CMakeLists.txt
@@ -0,0 +1,10 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_configproxy-cmd_app
+    SOURCES
+    main.cpp
+    methods.cpp
+    proxycmd.cpp
+    OUTPUT_NAME configproxy-cmd
+    INSTALL bin
+    DEPENDS
+)
diff --git a/config/src/apps/configproxy-cmd/flags.h b/config/src/apps/configproxy-cmd/flags.h
new file mode 100644
index 00000000000..ce64889256b
--- /dev/null
+++ b/config/src/apps/configproxy-cmd/flags.h
@@ -0,0 +1,14 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+#include <vector>
+
+struct Flags {
+    vespalib::string method;
+    std::vector<vespalib::string> args;
+    vespalib::string hostname;
+    int portnumber;
+    Flags() : method("cache"), args(), hostname("localhost"), portnumber(19090) {}
+};
+
diff --git a/config/src/apps/configproxy-cmd/main.cpp b/config/src/apps/configproxy-cmd/main.cpp
new file mode 100644
index 00000000000..34f2eeab143
--- /dev/null
+++ b/config/src/apps/configproxy-cmd/main.cpp
@@ -0,0 +1,90 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/fastos/fastos.h>
+#include <iostream>
+#include <vespa/vespalib/stllike/string.h>
+#include "flags.h"
+#include "proxycmd.h"
+#include "methods.h"
+
+class Application : public FastOS_Application
+{
+    Flags _flags;
+    bool parseOpts();
+public:
+    void usage(void);
+    int Main(void);
+
+    Application() : _flags() {}
+};
+
+bool
+Application::parseOpts()
+{
+    char c = '?';
+    const char *optArg = NULL;
+    int optInd = 0;
+    while ((c = GetOpt("m:s:p:", optArg, optInd)) != -1) {
+        switch (c) {
+        case 'm':
+            _flags.method = optArg;
+            break;
+        case 's':
+            _flags.hostname = optArg;
+            break;
+        case 'p':
+            _flags.portnumber = atoi(optArg);
+            break;
+        case 'h':
+        default:
+            return false; // triggers usage()
+        }
+    }
+    const Method method = methods::find(_flags.method);
+    if (optInd + method.args <= _argc) {
+        for (int i = 0; i < method.args; ++i) {
+            vespalib::string arg = _argv[optInd++];
+            _flags.args.push_back(arg);
+        }
+    } else {
+        std::cerr << "ERROR: method "<< _flags.method << " requires " << method.args
+                  << " arguments, only got " << (_argc - optInd) << std::endl;
+        return false;
+    }
+    if (optInd != _argc) {
+        std::cerr << "ERROR: "<<(_argc - optInd)<<" extra arguments\n";
+        return false;
+    }
+    _flags.method = method.rpcMethod;
+    return true;
+}
+
+void
+Application::usage(void)
+{
+    std::cerr <<
+        "Usage: configproxy-cmd [options]"                                 << std::endl <<
+        "    -m <method>                   method"                         << std::endl <<
+        "    -s <hostname>                 hostname (default: localhost)"  << std::endl <<
+        "    -p <port>                     port number (default: 19090)"   << std::endl <<
+        "Available methods for -m option:"                                 << std::endl;
+    methods::dump();
+}
+
+int
+Application::Main(void)
+{
+    if (! parseOpts()) {
+        usage();
+        return 1;
+    }
+    ProxyCmd client(_flags);
+    return client.action();
+}
+
+int
+main(int argc, char** argv)
+{
+    Application app;
+    return app.Entry(argc, argv);
+}
diff --git a/config/src/apps/configproxy-cmd/methods.cpp b/config/src/apps/configproxy-cmd/methods.cpp
new file mode 100644
index 00000000000..8345316c6a4
--- /dev/null
+++ b/config/src/apps/configproxy-cmd/methods.cpp
@@ -0,0 +1,45 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include "methods.h"
+#include <iostream>
+
+namespace methods {
+
+const Method methods[] = {
+    { "cache", "listCachedConfig", 0 },
+    { "dumpcache", "dumpCache", 1 }, // filename
+    { "getConfig", "getConfig", 7 }, // defName defVersion defMD5 configid configMD5 timestamp timeout
+    { "getmode", "getMode", 0 },
+    { "invalidatecache", "invalidateCache", 0 },
+    { "cachefull", "listCachedConfigFull", 0 },
+    { "sources", "listSourceConnections", 0 },
+    { "statistics", "printStatistics", 0 },
+    { "setmode", "setMode", 1 }, // { default | memorycache | diskcache }
+    { "updatesources", "updateSources", 1 },
+    { 0, 0, 0}
+};
+
+const Method find(const vespalib::string &name) {
+    for (size_t i = 0; methods[i].shortName != 0; ++i) {
+        if (name == methods[i].shortName) {
+            return methods[i];
+        }
+    }
+    Method rv = { name.c_str(), name.c_str(), 0 };
+    return rv;
+}
+
+void dump() {
+    std::cerr << "    ";
+    size_t i = 0;
+    for (;;) {
+        std::cerr << methods[i++].shortName;
+        if (methods[i].shortName == 0) {
+            break;
+        }
+        std::cerr << ",";
+    }
+    std::cerr << std::endl;
+}
+
+};
diff --git a/config/src/apps/configproxy-cmd/methods.h b/config/src/apps/configproxy-cmd/methods.h
new file mode 100644
index 00000000000..01f54a0a9d9
--- /dev/null
+++ b/config/src/apps/configproxy-cmd/methods.h
@@ -0,0 +1,18 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+
+struct Method {
+    const char *shortName;
+    const char *rpcMethod;
+    const int args;
+};
+
+namespace methods {
+
+const Method find(const vespalib::string &name);
+void dump();
+
+};
+
diff --git a/config/src/apps/configproxy-cmd/proxycmd.cpp b/config/src/apps/configproxy-cmd/proxycmd.cpp
new file mode 100644
index 00000000000..34bd354c79f
--- /dev/null
+++ b/config/src/apps/configproxy-cmd/proxycmd.cpp
@@ -0,0 +1,85 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include "proxycmd.h"
+#include <iostream>
+#include <vespa/vespalib/util/vstringfmt.h>
+
+ProxyCmd::ProxyCmd(const Flags& flags)
+    : _supervisor(NULL),
+      _target(NULL),
+      _req(NULL),
+      _flags(flags)
+{}
+
+void ProxyCmd::initRPC() {
+    _supervisor = new FRT_Supervisor();
+    _req = _supervisor->AllocRPCRequest();
+    _supervisor->Start();
+}
+
+void ProxyCmd::invokeRPC() {
+    if (_req == NULL) return;
+    _target->InvokeSync(_req, 65.0);
+}
+
+void ProxyCmd::finiRPC() {
+    if (_req != NULL) {
+        _req->SubRef();
+        _req = NULL;
+    }
+    if (_target != NULL) {
+        _target->SubRef();
+        _target = NULL;
+    }
+    if (_supervisor != NULL) {
+        _supervisor->ShutDown(true);
+        delete _supervisor;
+        _supervisor = NULL;
+    }
+}
+
+void ProxyCmd::printArray(FRT_Values *rvals) {
+    FRT_Value &lines = rvals->GetValue(0);
+    for (size_t i = 0; i < lines._string_array._len; ++i) {
+        std::cout << lines._string_array._pt[i]._str << std::endl;
+    }
+}
+
+vespalib::string ProxyCmd::makeSpec() {
+    return vespalib::make_vespa_string("tcp/%s:%d", _flags.hostname.c_str(), _flags.portnumber);
+}
+
+void ProxyCmd::autoPrint() {
+    if (_req->IsError()) {
+        std::cerr << "FAILURE ["<< _req->GetMethodName() <<"]: " << _req->GetErrorMessage() << std::endl;
+        return;
+    }
+    vespalib::string retspec = _req->GetReturnSpec();
+    FRT_Values *rvals = _req->GetReturn();
+    if (retspec == "S") {
+        printArray(rvals);
+    } else if (retspec == "s") {
+        std::cout << rvals->GetValue(0)._string._str << std::endl;
+    } else if (retspec == "i") {
+        std::cout << rvals->GetValue(0)._intval32 << std::endl;
+    } else {
+        _req->Print();
+    }
+}
+
+int ProxyCmd::action() {
+    int errors = 0;
+    initRPC();
+    vespalib::string spec = makeSpec();
+    _target = _supervisor->GetTarget(spec.c_str());
+    _req->SetMethodName(_flags.method.c_str());
+    FRT_Values &params = *_req->GetParams();
+    for (size_t i = 0; i < _flags.args.size(); ++i) {
+        params.AddString(_flags.args[i].c_str(), _flags.args[i].size());
+    }
+    invokeRPC();
+    if (_req->IsError()) ++errors;
+    autoPrint();
+    finiRPC();
+    return errors;
+}
diff --git a/config/src/apps/configproxy-cmd/proxycmd.h b/config/src/apps/configproxy-cmd/proxycmd.h
new file mode 100644
index 00000000000..6fc8261991f
--- /dev/null
+++ b/config/src/apps/configproxy-cmd/proxycmd.h
@@ -0,0 +1,30 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "flags.h"
+#include <vespa/fnet/frt/frt.h>
+
+
+class ProxyCmd
+{
+private:
+    FRT_Supervisor *_supervisor;
+    FRT_Target     *_target;
+    FRT_RPCRequest *_req;
+    Flags           _flags;
+
+    void initRPC();
+    void invokeRPC();
+    void finiRPC();
+    void printArray(FRT_Values *rvals);
+    vespalib::string makeSpec();
+    void autoPrint();
+public:
+    ProxyCmd(const Flags& flags);
+
+    virtual ~ProxyCmd() {}
+
+    int action();
+};
+
+
diff --git a/config/src/apps/getvespaconfig/.gitignore b/config/src/apps/getvespaconfig/.gitignore
new file mode 100644
index 00000000000..900ac81ea9b
--- /dev/null
+++ b/config/src/apps/getvespaconfig/.gitignore
@@ -0,0 +1,4 @@
+/.depend
+/Makefile
+/getvespaconfig
+getvespaconfig-bin
diff --git a/config/src/apps/getvespaconfig/CMakeLists.txt b/config/src/apps/getvespaconfig/CMakeLists.txt
new file mode 100644
index 00000000000..93022581b30
--- /dev/null
+++ b/config/src/apps/getvespaconfig/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_getvespaconfig_app
+    SOURCES
+    getconfig.cpp
+    OUTPUT_NAME getvespaconfig-bin
+    INSTALL bin
+    DEPENDS
+    config_cloudconfig
+)
diff --git a/config/src/apps/getvespaconfig/getconfig.cpp b/config/src/apps/getvespaconfig/getconfig.cpp
new file mode 100644
index 00000000000..95e804381d0
--- /dev/null
+++ b/config/src/apps/getvespaconfig/getconfig.cpp
@@ -0,0 +1,265 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+
+#include <vespa/log/log.h>
+LOG_SETUP("getconfig");
+
+#include <vespa/fnet/frt/frt.h>
+#include <vespa/config/config.h>
+#include <vespa/config/frt/protocol.h>
+#include <vespa/config/frt/frtconfigrequestfactory.h>
+#include <vespa/config/frt/frtconnection.h>
+#include <vespa/config/common/payload_converter.h>
+#include <vespa/config/common/vespa_version.h>
+
+#include <string>
+#include <sstream>
+#include <fstream>
+
+using namespace config;
+
+class GetConfig : public FastOS_Application
+{
+private:
+    FRT_Supervisor *_supervisor;
+    FRT_Target     *_target;
+
+    GetConfig(const GetConfig &);
+    GetConfig &operator=(const GetConfig &);
+
+public:
+    GetConfig() : _supervisor(NULL), _target(NULL) {}
+    virtual ~GetConfig();
+    int usage();
+    void initRPC(const char *spec);
+    void finiRPC();
+    virtual int Main();
+};
+
+
+GetConfig::~GetConfig()
+{
+    LOG_ASSERT(_supervisor == NULL);
+    LOG_ASSERT(_target == NULL);
+}
+
+
+int
+GetConfig::usage()
+{
+    fprintf(stderr, "usage: %s -n name -i configId\n", _argv[0]);
+    fprintf(stderr, "-n name           (config name, including namespace, on the form <namespace>.<name>)\n");
+    fprintf(stderr, "-i configId       (config id, optional)\n");
+    fprintf(stderr, "-j                (output config as json)\n");
+    fprintf(stderr, "-a schema         (config def schema file, optional)\n");
+    fprintf(stderr, "-v defVersion     (config definition version, optional, deprecated)\n");
+    fprintf(stderr, "-m defMd5         (definition md5sum, optional)\n");
+    fprintf(stderr, "-c configMd5      (config md5sum, optional)\n");
+    fprintf(stderr, "-t serverTimeout  (server timeout in seconds, default 3)\n");
+    fprintf(stderr, "-w timeout        (timeout in seconds, default 10)\n");
+    fprintf(stderr, "-s server         (server hostname, default localhost)\n");
+    fprintf(stderr, "-p port           (proxy/server port number, default 19090)\n");
+    fprintf(stderr, "-r traceLevel     (tracelevel to use in request, default 0\n");
+    fprintf(stderr, "-V vespaVersion   (vespa version to use in request, optional\n");
+    fprintf(stderr, "-d                (debug mode)\n");
+    fprintf(stderr, "-h                (This help text)\n");
+    return 1;
+}
+
+
+void
+GetConfig::initRPC(const char *spec)
+{
+    _supervisor = new FRT_Supervisor();
+    _target     = _supervisor->GetTarget(spec);
+    _supervisor->Start();
+}
+
+
+void
+GetConfig::finiRPC()
+{
+    if (_target != NULL) {
+        _target->SubRef();
+        _target = NULL;
+    }
+    if (_supervisor != NULL) {
+        _supervisor->ShutDown(true);
+        delete _supervisor;
+        _supervisor = NULL;
+    }
+}
+
+
+int
+GetConfig::Main()
+{
+    bool debugging = false;
+    char c = -1;
+
+    std::vector<vespalib::string> defSchema;
+    const char *schema = NULL;
+    const char *defName = NULL;
+    const char *defMD5 = "";
+    std::string defNamespace("config");
+    const char *serverHost = "localhost";
+    const char *configId = getenv("VESPA_CONFIG_ID");
+    bool printAsJson = false;
+    int traceLevel = config::protocol::readTraceLevel();
+    const char *vespaVersionString = nullptr;
+
+    if (configId == NULL) {
+        configId = "";
+    }
+    const char *configMD5 = "";
+    int serverTimeout = 3;
+    int clientTimeout = 10;
+
+    int serverPort = 19090;
+
+    const char *optArg = NULL;
+    int optInd = 0;
+    while ((c = GetOpt("a:n:v:i:jm:c:t:V:w:r:s:p:dh", optArg, optInd)) != -1) {
+        int retval = 1;
+        switch (c) {
+        case 'a':
+            schema = optArg;
+            break;
+        case 'n':
+            defName = optArg;
+            break;
+        case 'v':
+            break;
+        case 'i':
+            configId = optArg;
+            break;
+        case 'j':
+            printAsJson = true;
+            break;
+        case 'm':
+            defMD5 = optArg;
+            break;
+        case 'c':
+            configMD5 = optArg;
+            break;
+        case 't':
+            serverTimeout = atoi(optArg);
+            break;
+        case 'w':
+            clientTimeout = atoi(optArg);
+            break;
+        case 'r':
+            traceLevel = atoi(optArg);
+            break;
+        case 'V':
+            vespaVersionString = optArg;
+            break;
+        case 's':
+            serverHost = optArg;
+            break;
+        case 'p':
+            serverPort = atoi(optArg);
+            break;
+        case 'd':
+            debugging = true;
+            break;
+        case 'h':
+            retval = 0;
+        case '?':
+        default:
+            usage();
+            return retval;
+        }
+    }
+
+    if (defName == NULL || serverPort == 0) {
+        usage();
+        return 1;
+    }
+
+    if (strchr(defName, '.') != NULL) {
+        const char *tmp = defName;
+        defName = strrchr(defName, '.');
+        defName++;
+        defNamespace = std::string(tmp, defName - tmp - 1);
+    }
+
+    if (schema != NULL) {
+        std::ifstream is;
+        is.open(schema);
+        std::string item;
+        while (std::getline(is, item)) {
+            if (item.find("namespace=") == std::string::npos) {
+                defSchema.push_back(item);
+            }
+        }
+        is.close();
+    }
+    std::ostringstream tmp;
+    tmp << "tcp/";
+    tmp << serverHost;
+    tmp << ":";
+    tmp << serverPort;
+    std::string sspec = tmp.str();
+    const char *spec = sspec.c_str();
+    if (debugging) {
+        printf("connecting to '%s'\n", spec);
+    }
+    initRPC(spec);
+
+    auto vespaVersion = VespaVersion::getCurrentVersion();
+    if (vespaVersionString != nullptr) {
+        vespaVersion = VespaVersion::fromString(vespaVersionString);
+    }
+
+    int protocolVersion = config::protocol::readProtocolVersion();
+    FRTConfigRequestFactory requestFactory(protocolVersion, traceLevel, vespaVersion, config::protocol::readProtocolCompressionType());
+    FRTConnection connection(spec, *_supervisor, TimingValues());
+    ConfigKey key(configId, defName, defNamespace, defMD5, defSchema);
+    ConfigState state(configMD5, 0);
+    FRTConfigRequest::UP request = requestFactory.createConfigRequest(key, &connection, state, serverTimeout * 1000);
+
+    _target->InvokeSync(request->getRequest(), clientTimeout); // seconds
+
+    ConfigResponse::UP response = request->createResponse(request->getRequest());
+    response->validateResponse();
+    if (response->isError()) {
+        fprintf(stderr, "error %d: %s\n",
+                response->errorCode(), response->errorMessage().c_str());
+    } else {
+        response->fill();
+        ConfigKey rKey(response->getKey());
+        ConfigState rState(response->getConfigState());
+        ConfigValue rValue(response->getValue());
+        if (debugging) {
+            printf("defName    %s\n", rKey.getDefName().c_str());
+            printf("defMD5     %s\n", rKey.getDefMd5().c_str());
+            printf("defNamespace %s\n", rKey.getDefNamespace().c_str());
+
+            printf("configID   %s\n", rKey.getConfigId().c_str());
+            printf("configMD5  %s\n", rState.md5.c_str());
+
+            printf("generation  %" PRId64 "\n", rState.generation);
+            printf("trace       %s\n", response->getTrace().toString().c_str());
+        } else if (traceLevel > 0) {
+            printf("trace       %s\n", response->getTrace().toString().c_str());
+        }
+        // TODO: Make printAsJson default
+        if (printAsJson) {
+            printf("%s\n", rValue.asJson().c_str());
+        } else {
+            std::vector<vespalib::string> lines = rValue.getLegacyFormat();
+            for (uint32_t j = 0; j < lines.size(); j++) {
+                printf("%s\n",  lines[j].c_str());
+            }
+        }
+    }
+    finiRPC();
+    return 0;
+}
+
+int main(int argc, char **argv)
+{
+    GetConfig app;
+    return app.Entry(argc, argv);
+}
diff --git a/config/src/apps/pingproxy/.gitignore b/config/src/apps/pingproxy/.gitignore
new file mode 100644
index 00000000000..778ea35818c
--- /dev/null
+++ b/config/src/apps/pingproxy/.gitignore
@@ -0,0 +1,3 @@
+/.depend
+/Makefile
+/pingproxy
diff --git a/config/src/apps/pingproxy/CMakeLists.txt b/config/src/apps/pingproxy/CMakeLists.txt
new file mode 100644
index 00000000000..60f06a4399e
--- /dev/null
+++ b/config/src/apps/pingproxy/CMakeLists.txt
@@ -0,0 +1,8 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_pingproxy_app
+    SOURCES
+    pingproxy.cpp
+    OUTPUT_NAME pingproxy
+    INSTALL bin
+    DEPENDS
+)
diff --git a/config/src/apps/pingproxy/pingproxy.cpp b/config/src/apps/pingproxy/pingproxy.cpp
new file mode 100644
index 00000000000..444d024e240
--- /dev/null
+++ b/config/src/apps/pingproxy/pingproxy.cpp
@@ -0,0 +1,157 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+
+#include <vespa/log/log.h>
+LOG_SETUP("pingproxy");
+
+#include <vespa/fnet/frt/frt.h>
+
+#include <string>
+#include <sstream>
+
+
+class PingProxy : public FastOS_Application
+{
+private:
+    FRT_Supervisor *_supervisor;
+    FRT_Target     *_target;
+
+    PingProxy(const PingProxy &);
+    PingProxy &operator=(const PingProxy &);
+
+public:
+    PingProxy() : _supervisor(NULL), _target(NULL) {}
+    virtual ~PingProxy();
+    int usage();
+    void initRPC(const char *spec);
+    void finiRPC();
+    virtual int Main();
+};
+
+
+PingProxy::~PingProxy()
+{
+    LOG_ASSERT(_supervisor == NULL);
+    LOG_ASSERT(_target == NULL);
+}
+
+
+int
+PingProxy::usage()
+{
+    fprintf(stderr, "usage: %s\n", _argv[0]);
+    fprintf(stderr, "-s [server]        (server hostname, default localhost)\n");
+    fprintf(stderr, "-p [port]          (server port number, default 19090)\n");
+    return 1;
+}
+
+
+void
+PingProxy::initRPC(const char *spec)
+{
+    _supervisor = new FRT_Supervisor();
+    _target     = _supervisor->GetTarget(spec);
+    _supervisor->Start();
+}
+
+
+void
+PingProxy::finiRPC()
+{
+    if (_target != NULL) {
+        _target->SubRef();
+        _target = NULL;
+    }
+    if (_supervisor != NULL) {
+        _supervisor->ShutDown(true);
+        delete _supervisor;
+        _supervisor = NULL;
+    }
+}
+
+
+int
+PingProxy::Main()
+{
+    int retval = 0;
+    bool debugging = false;
+    char c = -1;
+
+    const char *serverHost = "localhost";
+    int clientTimeout = 5;
+    int serverPort = 19090;
+
+    const char *optArg = NULL;
+    int optInd = 0;
+    while ((c = GetOpt("w:s:p:dh", optArg, optInd)) != -1) {
+        switch (c) {
+        case 'w':
+            clientTimeout = atoi(optArg);
+            break;
+        case 's':
+            serverHost = optArg;
+            break;
+        case 'p':
+            serverPort = atoi(optArg);
+            break;
+        case 'd':
+            debugging = true;
+            break;
+        case '?':
+        default:
+            retval = 1;
+            // fallthrough
+        case 'h':
+            usage();
+            return retval;
+        }
+    }
+
+    if (serverPort == 0) {
+        usage();
+        return 1;
+    }
+
+    std::ostringstream tmp;
+    tmp << "tcp/";
+    tmp << serverHost;
+    tmp << ":";
+    tmp << serverPort;
+    std::string sspec = tmp.str();
+    const char *spec = sspec.c_str();
+    if (debugging) {
+        printf("connecting to '%s'\n", spec);
+    }
+    initRPC(spec);
+
+    FRT_RPCRequest *req = _supervisor->AllocRPCRequest();
+
+    req->SetMethodName("ping");
+
+    _target->InvokeSync(req, clientTimeout); // seconds
+
+    if (req->IsError()) {
+        retval = 1;
+        fprintf(stderr, "error %d: %s\n",
+                req->GetErrorCode(), req->GetErrorMessage());
+    } else {
+        FRT_Values &answer = *(req->GetReturn());
+        const char *atypes = answer.GetTypeString();
+        if (strcmp(atypes, "i") == 0) {
+            if (debugging) {
+                printf("ping %d\n", answer[0]._intval32);
+            }
+        } else {
+            fprintf(stderr, "unexpected return types in RPC answer: '%s'\n", atypes);
+            retval = 1;
+        }
+    }
+    finiRPC();
+    return retval;
+}
+
+int main(int argc, char **argv)
+{
+    PingProxy app;
+    return app.Entry(argc, argv);
+}
diff --git a/config/src/apps/vespa-config/vespa-config.pl b/config/src/apps/vespa-config/vespa-config.pl
new file mode 100755
index 00000000000..a87e5e52976
--- /dev/null
+++ b/config/src/apps/vespa-config/vespa-config.pl
@@ -0,0 +1,383 @@
+#!/usr/local/bin/perl -w
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#
+# Various small functions used when bootstrapping the config system
+
+# BEGIN perl environment bootstrap section
+# Do not edit between here and END as this section should stay identical in all scripts
+
+use File::Basename;
+use File::Path;
+
+sub findpath {
+    my $myfullname = ${0};
+    my($myname, $mypath) = fileparse($myfullname);
+
+    return $mypath if ( $mypath && -d $mypath );
+    $mypath=`pwd`;
+
+    my $pwdfullname = $mypath . "/" . $myname;
+    return $mypath if ( -f $pwdfullname );
+    return 0;
+}
+
+# Returns the argument path if it seems to point to VESPA_HOME, 0 otherwise
+sub is_vespa_home {
+    my($VESPA_HOME) = shift;
+    my $COMMON_ENV="libexec/vespa/common-env.sh";
+    if ( $VESPA_HOME && -d $VESPA_HOME ) {
+        my $common_env = $VESPA_HOME . "/" . $COMMON_ENV;
+        return $VESPA_HOME if -f $common_env;
+    }
+    return 0;
+}
+
+# Returns the home of Vespa, or dies if it cannot
+sub findhome {
+    # Try the VESPA_HOME env variable
+    return $ENV{'VESPA_HOME'} if is_vespa_home($ENV{'VESPA_HOME'});
+    if ( $ENV{'VESPA_HOME'} ) { # was set, but not correctly
+        die "FATAL: bad VESPA_HOME value '" . $ENV{'VESPA_HOME'} . "'\n";
+    }
+
+    # Try the ROOT env variable
+    $ROOT = $ENV{'ROOT'};
+    return $ROOT if is_vespa_home($ROOT);
+
+    # Try the script location or current dir
+    my $mypath = findpath();
+    if ($mypath) {
+        while ( $mypath =~ s|/[^/]*$|| ) {
+            return $mypath if is_vespa_home($mypath);
+        }
+    }
+    die "FATAL: Missing VESPA_HOME environment variable\n";
+}
+
+BEGIN {
+    my $tmp = findhome();
+    if ( $tmp !~ m{[/]$} ) { $tmp .= "/"; }
+    $ENV{'VESPA_HOME'} = $tmp;
+}
+my $VESPA_HOME = $ENV{'VESPA_HOME'};
+
+# END perl environment bootstrap section
+
+use lib $ENV{'VESPA_HOME'} . '/lib/perl5/site_perl';
+use Yahoo::Vespa::Defaults;
+readConfFile();
+
+use strict;
+use warnings;
+use File::Copy;
+use File::Temp;
+
+my $default_configproxy_port = "19090";
+my $default_configserver_port = "19070";
+my $zk_client_port;
+
+my $base_cfg_dir = $VESPA_HOME . "conf/vespa";
+
+# Set this to 1 to look up values (see getValue) in config files instead
+# of in environment variables
+my $lookupInConfig = 0;
+
+sub vespa_base_env {
+    $zk_client_port = getCCSVar('zookeeper_clientPort', 2181);
+}
+
+sub getValue {
+    my ($varname, $prefix) = @_;
+    if ($lookupInConfig) {
+	return getConfigValue($varname, $prefix);
+    } 
+    else {
+        return getEnvironmentValue($varname, $prefix);
+    }
+}
+
+sub getConfigValue {
+    my ($varname, $config) = @_;
+    my $path = "$base_cfg_dir/$config.conf";
+    if (open(CFG, "<$path")) {
+        while (<CFG>) {
+            chomp;
+            if ( m{^(\w+)\s(.+)} ) {
+		return $2 if $1 eq $varname;
+            }
+        }
+        close(CFG);
+    }
+    return;
+}
+
+sub getEnvironmentValue {
+    my ($varname, $prefix) = @_;
+    my $value = $ENV{$prefix . "__" . $varname};
+    if (defined $value && $value =~ m{^\s*(\S.*)\s*}) {
+        return $1;
+    }
+    return $value;
+}
+
+sub getCCSVar {
+    my ($varname, $default) = @_;
+    my $value = getValue($varname, "cloudconfig_server");
+    if (defined($value)) {
+        return $value;
+    }
+    return $default;
+}
+
+sub getVar {
+    my ($varname, $default, $warn) = @_;
+    # print "GET var '$varname'\n";
+    my $cloud = getValue($varname, "services");
+    my $vespa = getValue($varname, "vespa_base");
+    if (defined($cloud) && defined($vespa)) {
+        print STDERR "Found settings for both services.$varname and vespa_base.$varname, using settings from services\n";
+    }
+    if (defined($cloud)) {
+        return $cloud;
+    } elsif (defined($vespa)) {
+        return $vespa;
+    } elsif ($warn > 0) {
+        print STDERR "No value found for 'services.$varname' or 'vespa_base.$varname'; using '$default'\n";
+    }
+    return $default;
+}
+
+sub printConfigServerPort {
+    my $port = getVar('port_configserver_rpc', $default_configserver_port, 0);
+    print "$port\n";
+}
+
+sub getConfigServers {
+    my @ret;
+
+    my $hostname = `hostname`;
+    chomp $hostname;
+
+    my $addr = getVar('addr_configserver', $hostname, 1);
+    my $port = getVar('port_configserver_rpc', $default_configserver_port, 0);
+
+    my $h;
+    foreach $h (split(/,|\s+/, $addr)) {
+        if ($h =~ m{(\S+:\d+)}) {
+            push @ret, $1;
+        } else {
+            push @ret, "${h}:${port}";
+        }
+    }
+    return @ret;
+}
+
+sub getZKString {
+    my $out;
+    my $addr;
+    foreach $addr (getConfigServers()) {
+        $addr =~ s{:\d+}{:$zk_client_port,};
+        $out .= $addr;
+    }
+    chop($out);                 # last comma
+    return $out;
+}
+
+sub printZKString {
+    my $out = getZKString();
+    print $out . "\n";
+}
+
+sub printAllConfigSourcesWithPort {
+    my $cfport = getVar('port_configserver_rpc', $default_configserver_port, 0);
+    my $cpport = getVar('port_configproxy_rpc',  $default_configproxy_port,  0);
+    my $addr = "localhost";
+    my $out = "tcp/${addr}:${cpport}";
+    foreach $addr (getConfigServers()) {
+        if ($addr =~ m{\/}) {
+            if ($addr =~ m{\:}) {
+                $out .= ",${addr}";
+            } else {
+                $out .= ",${addr}:${cfport}";
+            }
+        } else {
+            if ($addr =~ m{\:}) {
+                $out .= ",tcp/${addr}";
+            } else {
+                $out .= ",tcp/${addr}:${cfport}";
+            }
+        }
+    }
+    print $out . "\n";
+}
+
+sub printConfigSources {
+    my $out;
+    my $addr;
+    foreach $addr (getConfigServers()) {
+        $out .= "tcp/${addr},";
+    }
+    chop($out);                 # last comma
+    print $out . "\n";
+}
+
+sub printConfigHttpSources {
+    my $out;
+    my $addr;
+    foreach $addr (getConfigServers()) {
+        my $host = "";
+        my $port = 0;
+        if ($addr =~ /(.*):(\d+)$/) {
+            $host = $1;
+            $port = $2;
+        }
+        $port++;                        # HTTP is rpc + 1
+        $out .= "http://$host:$port ";
+    }
+    chop($out);                 # last space
+    print $out . "\n";
+}
+
+sub makeFiledistributorZKConfig {
+    my $cfgFile = $VESPA_HOME . "conf/filedistributor/zookeepers.cfg";
+    open(CFG, "> ${cfgFile}.new") or die "Cannot write to '${cfgFile}.new'";
+    my $zkservers = getZKString();
+    print CFG "zookeeperserverlist \"$zkservers\"\n";
+    close(CFG);
+    rename("${cfgFile}.new", ${cfgFile})
+        or die "Cannot rename '${cfgFile}.new' -> '${cfgFile}': $!\n";
+    print STDERR "wrote '${cfgFile}' \n";
+}
+
+sub makeFiledistributorDistributorConfig {
+    my $cfgFile = $VESPA_HOME . "conf/filedistributor/filedistributor.cfg";
+    open(CFG, "> ${cfgFile}.new") or die "Cannot write to '${cfgFile}.new'";
+    print CFG "torrentport 19093\n";
+    my $hostname = `hostname`;
+    chomp $hostname;
+    print CFG "hostname \"$hostname\"\n";
+    print CFG "filedbpath \"$VESPA_HOME" . "var/db/vespa/filedistribution\"\n";
+    print CFG "maxdownloadspeed 0\n";
+    print CFG "maxuploadspeed 0\n";
+    close(CFG);
+    rename("${cfgFile}.new", ${cfgFile})
+        or die "Cannot rename '${cfgFile}.new' -> '${cfgFile}': $!\n";
+    print STDERR "wrote '${cfgFile}' \n";
+}
+
+sub makeFiledistributorRpcConfig {
+    my $cfgFile = $VESPA_HOME . "conf/filedistributor/filedistributorrpc.cfg";
+    open(CFG, "> ${cfgFile}.new") or die "Cannot write to '${cfgFile}.new'";
+    my $hostname = `hostname`;
+    chomp $hostname;
+    print CFG "connectionspec \"tcp/$hostname:19092\"\n";
+    close(CFG);
+    rename("${cfgFile}.new", ${cfgFile})
+        or die "Cannot rename '${cfgFile}.new' -> '${cfgFile}': $!\n";
+    print STDERR "wrote '${cfgFile}' \n";
+}
+
+sub makeFiledistributorReferencesConfig {
+    my $cfgFile = $VESPA_HOME . "conf/filedistributor/filereferences.cfg";
+    open(CFG, "> ${cfgFile}.new") or die "Cannot write to '${cfgFile}.new'";
+    close(CFG);
+    rename("${cfgFile}.new", ${cfgFile})
+        or die "Cannot rename '${cfgFile}.new' -> '${cfgFile}': $!\n";
+    print STDERR "wrote '${cfgFile}' \n";
+}
+
+sub makeFiledistributorConfig {
+    makeFiledistributorZKConfig();
+    makeFiledistributorDistributorConfig();
+    makeFiledistributorRpcConfig();
+    makeFiledistributorReferencesConfig();
+}
+
+sub isThisAConfigServer {
+    my $hostnameForThisHost = `hostname`;
+    chomp $hostnameForThisHost;
+    my $addr;
+    foreach $addr (getConfigServers()) {
+        my $host = "";
+        my $port = 0;
+        if ($addr =~ /(.*):(\d+)$/) {
+            $host = $1;
+        }
+        if ($hostnameForThisHost eq $host or $host eq "localhost") {
+          print "yes\n";
+          exit 0;
+        }
+    }
+
+    print "no\n";
+    exit 1;
+}
+
+# Perl trim function to remove whitespace from the start and end of the string
+sub trim($) {
+    my $string = shift;
+    $string =~ s/^\s+//;
+    $string =~ s/\s+$//;
+    return $string;
+}
+
+sub getLastLine {
+    my ($file) = @_;
+    `grep -v \"\^\$\" $file | tail -n 1` # skip blank lines
+}
+
+sub usage {
+    print "usage: ";
+    print "vespa-config [-configsources | -confighttpsources | -zkstring | -mkfiledistributorconfig | -configserverport | -zkclientport | -isthisaconfigserver]\n";
+}
+
+if ( @ARGV == 0 ) {
+    usage();
+    exit 1;
+}
+
+if ( $ARGV[0] eq "-allconfigsources" ) {
+    vespa_base_env();
+    printAllConfigSourcesWithPort();
+    exit 0;
+}
+if ( $ARGV[0] eq "-configsources" ) {
+    vespa_base_env();
+    printConfigSources();
+    exit 0;
+}
+if ( $ARGV[0] eq "-confighttpsources" ) {
+    $lookupInConfig = 1;
+    vespa_base_env();
+    printConfigHttpSources();
+    exit 0;
+}
+if ( $ARGV[0] eq "-zkstring" ) {
+    vespa_base_env();
+    printZKString();
+    exit 0;
+}
+if ( $ARGV[0] eq "-configserverport" ) {
+    $lookupInConfig = 1;
+    vespa_base_env();
+    printConfigServerPort();
+    exit 0;
+}
+if ( $ARGV[0] eq "-mkfiledistributorconfig" ) {
+    vespa_base_env();
+    makeFiledistributorConfig();
+    exit 0;
+}
+if ( $ARGV[0] eq "-zkclientport" ) {
+    vespa_base_env();
+    print "$zk_client_port\n";
+    exit 0;
+}
+if ( $ARGV[0] eq "-isthisaconfigserver" ) {
+    vespa_base_env();
+    isThisAConfigServer();
+    exit 0;
+}
+
+usage();
+exit 1;
diff --git a/config/src/main/java/.gitignore b/config/src/main/java/.gitignore
new file mode 100644
index 00000000000..4cb44b1b2b5
--- /dev/null
+++ b/config/src/main/java/.gitignore
@@ -0,0 +1 @@
+/deploy
diff --git a/config/src/main/java/com/yahoo/config/codegen/package-info.java b/config/src/main/java/com/yahoo/config/codegen/package-info.java
new file mode 100644
index 00000000000..b83f806cf87
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/codegen/package-info.java
@@ -0,0 +1,5 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+@ExportPackage
+package com.yahoo.config.codegen;
+
+import com.yahoo.osgi.annotation.ExportPackage;
diff --git a/config/src/main/java/com/yahoo/config/subscription/CfgConfigPayloadBuilder.java b/config/src/main/java/com/yahoo/config/subscription/CfgConfigPayloadBuilder.java
new file mode 100644
index 00000000000..1216efcbec5
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/CfgConfigPayloadBuilder.java
@@ -0,0 +1,200 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.collections.Pair;
+import com.yahoo.config.ConfigurationRuntimeException;
+import com.yahoo.config.StringNode;
+import com.yahoo.log.LogLevel;
+import com.yahoo.vespa.config.ConfigPayload;
+import com.yahoo.vespa.config.ConfigPayloadBuilder;
+
+import java.util.*;
+
+/**
+ * Deserializes config payload (cfg format) to a ConfigPayload.
+ *
+ * @author <a href="mailto:musum@yahoo-inc.com">Harald Musum</a>
+ * @since 5.1.6
+ */
+public class CfgConfigPayloadBuilder {
+    private static final java.util.logging.Logger log = java.util.logging.Logger.getLogger(CfgConfigPayloadBuilder.class.getName());
+
+    /**
+     * Deserializes a config payload to slime
+     *
+     * @param lines a list with config payload strings
+     * @return an instance of the config class
+     */
+    public ConfigPayload deserialize(List<String> lines) {
+        return ConfigPayload.fromBuilder(deserializeToBuilder(lines));
+    }
+
+    public ConfigPayloadBuilder deserializeToBuilder(List<String> lines) {
+        int lineNum = 1;
+        ConfigPayloadBuilder payloadBuilder = new ConfigPayloadBuilder();
+        for (String line : lines) {
+            if (log.isLoggable(LogLevel.SPAM)) {
+               log.log(LogLevel.SPAM, "line " + lineNum + ": '" + line + "'");
+            }
+            parseLine(line, lineNum, payloadBuilder);
+            lineNum++;
+        }
+        if (log.isLoggable(LogLevel.DEBUG)) {
+            log.log(LogLevel.DEBUG, "payload=" + payloadBuilder.toString());
+        }
+        return payloadBuilder;
+    }
+
+    private void parseLine(final String line, int lineNum, ConfigPayloadBuilder payloadBuilder) {
+        String trimmedLine = line.trim();
+        if (trimmedLine.startsWith("#")) return;
+        Pair<String, String> fieldAndValue = parseFieldAndValue(trimmedLine);
+        String field = fieldAndValue.getFirst();
+        String value = fieldAndValue.getSecond();
+        if (field==null || value==null) {
+            log.log(LogLevel.DEBUG, "Got field without value in line " + lineNum + ": " + line + ", skipping");
+            return;
+        }
+        field=field.trim();
+        value=value.trim();
+        validateField(field, trimmedLine, lineNum);
+        validateValue(value, trimmedLine, lineNum);
+        if (log.isLoggable(LogLevel.DEBUG)) {
+            log.log(LogLevel.DEBUG, "field=" + field + ",value=" + value);
+        }
+        List<String> fields = parseFieldList(field);
+        ConfigPayloadBuilder currentBuilder = payloadBuilder;
+        for (int fieldNum = 0; fieldNum < fields.size(); fieldNum++) {
+            String fieldName = fields.get(fieldNum);
+            boolean isLeaf = (fieldNum == fields.size() - 1);
+            if (isLeaf) {
+                if (isArray(fieldName)) {
+                    // array leaf
+                    ConfigPayloadBuilder.Array array = currentBuilder.getArray(getArrayName(fieldName));
+                    array.set(getArrayIndex(fieldName), removeQuotes(value));
+                } else if (isMap(fieldName)) {
+                    // map leaf
+                    ConfigPayloadBuilder.MapBuilder map = currentBuilder.getMap(getMapName(fieldName));
+                    map.put(getMapKey(fieldName), removeQuotes(value));
+                } else {
+                    // scalar leaf value
+                    currentBuilder.setField(fieldName, removeQuotes(value));
+                }
+            } else {
+                if (isArray(fieldName)) {
+                    // array of structs
+                    ConfigPayloadBuilder.Array array = currentBuilder.getArray(getArrayName(fieldName));
+                    currentBuilder = array.get(getArrayIndex(fieldName));
+                } else if (isMap(fieldName)) {
+                    // map of structs
+                    ConfigPayloadBuilder.MapBuilder map = currentBuilder.getMap(getMapName(fieldName));
+                    currentBuilder = map.get(getMapKey(fieldName));
+                } else {
+                    // struct
+                    currentBuilder = currentBuilder.getObject(fieldName);
+                }
+            }
+        }
+    }
+
+    // split on space, but not if inside { } (map key)
+    Pair<String, String> parseFieldAndValue(String line) {
+        String field=null;
+        String value;
+        StringBuffer sb = new StringBuffer();
+        boolean inMapKey = false;
+        for (char c : line.toCharArray()) {
+            if (c=='{') inMapKey=true;
+            if (c=='}') inMapKey=false;
+            if (c==' ' && !inMapKey) {
+                if (field==null) {
+                    field = sb.toString();
+                    sb = new StringBuffer();
+                    continue;
+                }
+            }
+            sb.append(c);
+        }
+        value = sb.toString();
+        return new Pair<>(field, value);
+    }
+
+    // split on dot, but not if inside { } (map key)
+    List<String> parseFieldList(String field) {
+        List<String> ret = new ArrayList<>();
+        StringBuffer sb = new StringBuffer();
+        boolean inMapKey = false;
+        for (char c : field.toCharArray()) {
+            if (c=='{') inMapKey=true;
+            if (c=='}') inMapKey=false;
+            if (c=='.' && !inMapKey) {
+                ret.add(sb.toString());
+                sb = new StringBuffer();
+                continue;
+            }
+            sb.append(c);
+        }
+        ret.add(sb.toString());
+        return ret;
+    }
+
+    // TODO Need more validation
+    private void validateField(String field, String line, int lineNum) {
+        if (field.length() == 0) {
+            throw new ConfigurationRuntimeException("Error on line " + lineNum + ": " + line + "\n" +
+                    "'" + field + "' is not a valid field name");
+        }
+    }
+
+    // TODO Need more validation
+    private void validateValue(String value, String line, int lineNum) {
+        if (value.length() == 0) {
+            throw new ConfigurationRuntimeException("Error on line " + lineNum + ": " + line + "\n" +
+                    "'" + value + "' is not a valid value");
+        }
+    }
+
+    private boolean isArray(String name) {
+        return name.endsWith("]");
+    }
+
+    private boolean isMap(String name) {
+        return name.contains("{");
+    }
+
+    private String removeQuotes(String s) {
+        return StringNode.unescapeQuotedString(s);
+    }
+
+    private String getMapName(String name) {
+        if (name.contains("{")) {
+            return name.substring(0, name.indexOf("{"));
+        } else {
+            return name;
+        }
+    }
+
+    private String getMapKey(String name) {
+        if (name.contains("{")) {
+            return removeQuotes(name.substring(name.indexOf("{") + 1, name.indexOf("}")));
+        } else {
+            return "";
+        }
+    }
+
+    private String getArrayName(String name) {
+        if (name.contains("[")) {
+            return name.substring(0, name.indexOf("["));
+        } else {
+            return name;
+        }
+    }
+
+    private int getArrayIndex(String name) {
+        if (name.contains("[")) {
+            return Integer.parseInt(name.substring(name.indexOf("[") + 1, name.indexOf("]")));
+        } else {
+            return 0;
+        }
+    }
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/ConfigDebug.java b/config/src/main/java/com/yahoo/config/subscription/ConfigDebug.java
new file mode 100644
index 00000000000..add088cf349
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/ConfigDebug.java
@@ -0,0 +1,22 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.log.LogLevel;
+import com.yahoo.vespa.config.ConfigKey;
+
+import java.util.logging.Logger;
+
+// Debug class that provides useful helper routines
+public class ConfigDebug {
+    public static void logDebug(Logger logger, long timestamp, ConfigKey<?> key, String logmessage) {
+        if (key.getConfigId().matches(".*container.?\\d+.*") || key.getConfigId().matches(".*doc.api.*")) {
+            logger.log(LogLevel.INFO,  timestamp + " " + key + " " + logmessage);
+        }
+    }
+
+    public static void logDebug(Logger log, ConfigInstance.Builder builder, String configId, String logmessage) {
+        ConfigKey<?> key = new ConfigKey<>(builder.getDefName(), configId, builder.getDefNamespace());
+        logDebug(log, 0, key, logmessage);
+    }
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/ConfigGetter.java b/config/src/main/java/com/yahoo/config/subscription/ConfigGetter.java
new file mode 100755
index 00000000000..be4ff9f1b79
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/ConfigGetter.java
@@ -0,0 +1,89 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+
+import com.yahoo.config.ConfigInstance;
+
+/**
+ * This is a simple config getter that retrieves a config with a given class and configId through a
+ * simple method call. No subscription is retained when the config has been returned to the client.
+ *
+ * This class is mainly targeted to unit tests that do not want the extra complexity incurred by setting
+ * up their own subscriber. Another use-case is clients that get config, do a task, and exit, e.g.
+ * command-line tools.
+ *
+ * @author gjoranv
+ */
+public class ConfigGetter<T extends ConfigInstance> {
+
+    private final Class<T> clazz;
+    private final ConfigSource source;
+
+    /**
+     * Creates a ConfigGetter for class <code>clazz</code>
+     *
+     * @param clazz a config class
+     */
+    public ConfigGetter(Class<T> clazz) {
+        this(null, clazz);
+    }
+
+    /**
+     * Creates a ConfigGetter for class <code>clazz</code> with the specified
+     * {@link ConfigSource}.
+     *
+     * @param source a {@link ConfigSource}
+     * @param clazz  a config class
+     */
+    // TODO This is the order of arguments in com.yahoo.config.ConfigGetter and kept here, I would like to switch the order
+    public ConfigGetter(ConfigSource source, Class<T> clazz) {
+        this.clazz = clazz;
+        this.source = source;
+    }
+
+    /**
+     * Returns an instance of the config class specified in the constructor.
+     *
+     * @param configId a config id to use when getting the config
+     * @return an instance of a config class
+     */
+    public synchronized T getConfig(String configId) {
+        ConfigSubscriber subscriber;
+        ConfigHandle<T> h;
+        if (source == null) {
+            subscriber = new ConfigSubscriber();
+        } else {
+            subscriber = new ConfigSubscriber(source);
+        }
+        h = subscriber.subscribe(clazz, configId);
+        subscriber.nextConfig();
+        T ret = h.getConfig();
+        subscriber.close();
+        return ret;
+    }
+
+    /**
+     * Creates a ConfigGetter instance and returns an instance of the config class <code>c</code>.
+     *
+     * @param c        a config class
+     * @param configId a config id to use when getting the config
+     * @return an instance of a config class
+     */
+    public static <T extends ConfigInstance> T getConfig(Class<T> c, String configId) {
+        ConfigGetter<T> getter = new ConfigGetter<T>(c);
+        return getter.getConfig(configId);
+    }
+
+    /**
+     * Creates a ConfigGetter instance and returns an instance of the config class <code>c</code>.
+     *
+     * @param c        a config class
+     * @param configId a config id to use when getting the config
+     * @param source   a {@link ConfigSource}
+     * @return an instance of a config class
+     */
+    public static <T extends ConfigInstance> T getConfig(Class<T> c, String configId, ConfigSource source) {
+        ConfigGetter<T> getter = new ConfigGetter<T>(source, c);
+        return getter.getConfig(configId);
+    }
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/ConfigHandle.java b/config/src/main/java/com/yahoo/config/subscription/ConfigHandle.java
new file mode 100644
index 00000000000..6cc10be8627
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/ConfigHandle.java
@@ -0,0 +1,63 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.subscription.impl.ConfigSubscription;
+
+/**
+ * A config handle represents one config in the context of one active subscription on a {@link ConfigSubscriber}.
+ * It will contain meta data of the subscription of that particular config, as well as access to the {@link com.yahoo.config.ConfigInstance} itself.
+ *
+ * @param <T> the type of the config
+ * @author vegardh
+ * @since 5.1
+ */
+public class ConfigHandle<T extends ConfigInstance> {
+
+    private ConfigSubscription<T> sub;
+    private boolean changed = false;
+
+    protected ConfigHandle(ConfigSubscription<T> sub) {
+        this.sub = sub;
+    }
+
+    /**
+     * Returns true if:
+     *
+     * The config generation for the {@link ConfigSubscriber} that produced this is the first one in its life cycle. (Typically first time config.)
+     * or
+     * All configs for the subscriber have a new generation since the last time nextConfig() was called
+     * AND it's the same generation AND there is a change in <strong>this</strong> handle's config.
+     * (Typically calls for a reconfig.)
+     *
+     * @return there is a new config
+     */
+    public boolean isChanged() {
+        return changed;
+    }
+
+    void setChanged(boolean changed) {
+        this.changed = changed;
+    }
+
+    ConfigSubscription<T> subscription() {
+        return sub;
+    }
+
+    /**
+     * The config of this handle
+     *
+     * @return the config that this handle holds
+     */
+    public T getConfig() {
+        // TODO throw if subscriber not frozen?
+        return sub.getConfig();
+    }
+
+    @Override
+    public String toString() {
+        return "Handle changed: " + changed + "\nSub:\n" + sub.toString();
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/ConfigInstanceSerializer.java b/config/src/main/java/com/yahoo/config/subscription/ConfigInstanceSerializer.java
new file mode 100644
index 00000000000..cdb654fcbbb
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/ConfigInstanceSerializer.java
@@ -0,0 +1,93 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.config.Serializer;
+import com.yahoo.slime.Cursor;
+import com.yahoo.slime.Slime;
+
+/**
+ * Implements a config instance serializer, serializing a config instance to a slime object.
+ *
+ * @author lulf
+ * @since 5.1.14
+ */
+public class ConfigInstanceSerializer implements Serializer {
+    private final Slime slime;
+    private final Cursor root;
+    public ConfigInstanceSerializer(Slime slime) {
+        this.slime = slime;
+        root = slime.setObject();
+    }
+
+    public ConfigInstanceSerializer(Slime slime, Cursor root) {
+        this.slime = slime;
+        this.root = root;
+    }
+
+    @Override
+    public Serializer createInner(String name) {
+        Cursor childRoot = root.setObject(name);
+        return new ConfigInstanceSerializer(slime, childRoot);
+    }
+
+    @Override
+    public Serializer createArray(String name) {
+        return new ConfigInstanceSerializer(slime, root.setArray(name));
+    }
+
+    @Override
+    public Serializer createInner() {
+        return new ConfigInstanceSerializer(slime, root.addObject());
+    }
+
+    @Override
+    public Serializer createMap(String name) {
+        return createInner(name);
+    }
+
+    public void serialize(String name, boolean value) {
+        root.setBool(name, value);
+    }
+
+    public void serialize(String name, double value) {
+        root.setDouble(name, value);
+    }
+
+    public void serialize(String name, int value) {
+        root.setLong(name, value);
+    }
+
+    public void serialize(String name, long value) {
+        root.setLong(name, value);
+    }
+
+    public void serialize(String name, String value) {
+        root.setString(name, value);
+    }
+
+    @Override
+    public void serialize(boolean value) {
+        root.addBool(value);
+    }
+
+    @Override
+    public void serialize(double value) {
+        root.addDouble(value);
+    }
+
+    @Override
+    public void serialize(long value) {
+        root.addLong(value);
+    }
+
+    @Override
+    public void serialize(int value) {
+        root.addLong(value);
+    }
+
+    @Override
+    public void serialize(String value) {
+        root.addString(value);
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/ConfigInstanceUtil.java b/config/src/main/java/com/yahoo/config/subscription/ConfigInstanceUtil.java
new file mode 100644
index 00000000000..3c36bf7f105
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/ConfigInstanceUtil.java
@@ -0,0 +1,93 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import java.lang.reflect.Field;
+import java.lang.reflect.Method;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.InvocationTargetException;
+
+import com.yahoo.config.ConfigBuilder;
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.ConfigurationRuntimeException;
+import com.yahoo.yolean.Exceptions;
+import com.yahoo.vespa.config.*;
+
+/**
+ * @author gjoranv
+ * @since 5.1.6
+ */
+public class ConfigInstanceUtil {
+
+    /**
+     * Copies all values that have been explicitly set on the source to the destination.
+     * Values that have not been explicitly set in the source builder, will be left unchanged
+     * in the destination.
+     *
+     * @param destination The builder to copy values into.
+     * @param source The builder to copy values from. Unset values are not copied.
+     * @param <BUILDER> The builder class.
+     */
+    public static<BUILDER extends ConfigBuilder> void setValues(BUILDER destination, BUILDER source) {
+        try {
+            Method setter = destination.getClass().getDeclaredMethod("override", destination.getClass());
+            setter.setAccessible(true);
+            setter.invoke(destination, source);
+            setter.setAccessible(false);
+        } catch (Exception e) {
+            throw new ConfigurationRuntimeException("Could not set values on config builder."
+                    + destination.getClass().getName(), e);
+        }
+    }
+
+    public static <T extends ConfigInstance> T getNewInstance(Class<T> type,
+                                                              String configId,
+                                                              ConfigPayload payload) {
+        T instance;
+        try {
+            ConfigTransformer<?> transformer = new ConfigTransformer<T>(type);
+            ConfigBuilder instanceBuilder = transformer.toConfigBuilder(payload);
+            Constructor<T> constructor = type.getConstructor(instanceBuilder.getClass());
+            instance = constructor.newInstance((ConfigInstance.Builder) instanceBuilder);
+
+            // Workaround for JDK7, where compilation fails due to fields being
+            // private and not accessible from T. Reference it as a
+            // ConfigInstance to work around it. See
+            // http://bugs.sun.com/bugdatabase/view_bug.do?bug_id=7022052 for
+            // more information.
+            ConfigInstance i = instance;
+            i.postInitialize(configId);
+            setConfigId(i, configId);
+
+        } catch (InstantiationException | InvocationTargetException | NoSuchMethodException |
+                NoSuchFieldException | IllegalAccessException e) {
+            throw new IllegalArgumentException("Failed creating new instance of '" + type.getCanonicalName() +
+                    "' for config id '" + configId + "': " + Exceptions.toMessageString(e), e);
+        }
+        return instance;
+    }
+
+    private static void setConfigId(ConfigInstance instance, String configId)
+            throws NoSuchFieldException, IllegalAccessException {
+        Field configIdField = ConfigInstance.class.getDeclaredField("configId");
+        configIdField.setAccessible(true);
+        configIdField.set(instance, configId);
+        configIdField.setAccessible(false);
+    }
+
+    /**
+     * Gets the value of a private field on a Builder.
+     * @param builder a {@link com.yahoo.config.ConfigBuilder}
+     * @param fieldName a config field name
+     * @return the value of the private field
+     */
+    public static Object getField(ConfigBuilder builder, String fieldName) {
+        try {
+            Field f = builder.getClass().getDeclaredField(fieldName);
+            f.setAccessible(true);
+            return f.get(builder);
+        } catch (NoSuchFieldException | SecurityException | IllegalArgumentException | IllegalAccessException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/ConfigInterruptedException.java b/config/src/main/java/com/yahoo/config/subscription/ConfigInterruptedException.java
new file mode 100644
index 00000000000..ed1dca50096
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/ConfigInterruptedException.java
@@ -0,0 +1,14 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+/**
+ * This exception is thrown when any blocking call within the Config API is interrupted.
+ * @author lulf
+ * @since 5.1
+ */
+@SuppressWarnings("serial")
+public class ConfigInterruptedException extends RuntimeException {
+    public ConfigInterruptedException(Throwable cause) {
+        super(cause);
+    }
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/ConfigSet.java b/config/src/main/java/com/yahoo/config/subscription/ConfigSet.java
new file mode 100644
index 00000000000..1b516f333fa
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/ConfigSet.java
@@ -0,0 +1,61 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.vespa.config.ConfigKey;
+
+/**
+ * Config source as a programmatically built set of {@link com.yahoo.config.ConfigInstance}s
+ *
+ * @author vegardh
+ * @since 5.1
+ */
+public class ConfigSet implements ConfigSource {
+    private final Map<ConfigKey<?>, ConfigInstance.Builder> configs = new ConcurrentHashMap<>();
+
+    /**
+     * Inserts a new builder in this set. If an existing entry exists, it is overwritten.
+     *
+     * @param configId The config id for this builder.
+     * @param builder The builder that will produce config for the particular config id.
+     */
+    @SuppressWarnings({"unchecked", "rawtypes"})
+    public void addBuilder(String configId, ConfigInstance.Builder builder) {
+        Class<?> configClass = builder.getClass().getDeclaringClass();
+        //System.out.println("Declaring class for builder " + builder + " is " + configClass);
+        ConfigKey<?> key = new ConfigKey(configClass, configId);
+        configs.put(key, builder);
+    }
+
+    /**
+     * Returns a Builder matching the given key, or null if no match
+     *
+     * @param key a config key to get a Builder for
+     * @return a ConfigInstance
+     */
+    public ConfigInstance.Builder get(ConfigKey<?> key) {
+        return configs.get(key);
+    }
+
+    /**
+     * Returns true if this set contains a config instance matching the given key
+     *
+     * @param key a config key
+     * @return a ConfigInstance
+     */
+    public boolean contains(ConfigKey<?> key) {
+        return configs.containsKey(key);
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        for (Map.Entry<ConfigKey<?>, ConfigInstance.Builder> entry : configs.entrySet()) {
+            sb.append(entry.getKey()).append("=>").append(entry.getValue());
+        }
+        return sb.toString();
+    }
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/ConfigSource.java b/config/src/main/java/com/yahoo/config/subscription/ConfigSource.java
new file mode 100644
index 00000000000..44b65e4ba12
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/ConfigSource.java
@@ -0,0 +1,12 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+/**
+ * A type of source of config
+ * @author vegardh
+ * @since 5.1
+ *
+ */
+public interface ConfigSource {
+
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/ConfigSourceSet.java b/config/src/main/java/com/yahoo/config/subscription/ConfigSourceSet.java
new file mode 100755
index 00000000000..4c1757c0ba8
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/ConfigSourceSet.java
@@ -0,0 +1,127 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.log.LogLevel;
+
+import java.util.*;
+import java.util.logging.Logger;
+
+
+/**
+* An immutable set of connection endpoints, where each endpoint points to either a
+ * remote configserver or a configproxy.
+ *
+ * Two sets are said to be equal if they contain the same sources, independent of order,
+ * upper/lower-casing and whitespaces.
+ *
+ * @author <a href="gv@yahoo-inc.com">G. Voldengen</a>
+ */
+public class ConfigSourceSet implements ConfigSource
+{
+    private static final Logger log = Logger.getLogger(ConfigSourceSet.class.getName());
+    private final Set<String> sources = new LinkedHashSet<String>();
+
+    /**
+     * Creates an empty ConfigSourceSet, mostly used for unit testing.
+     */
+    public ConfigSourceSet() {
+    }
+
+    /**
+     * Creates a ConfigSourceSet containing all the unique given input addresses.
+     * Each address is trimmed and lower-cased before adding.
+     *
+     * @param addresses  Connection endpoints on the format "tcp/host:port".
+     */
+    public ConfigSourceSet(List<String> addresses) {
+        for (String a : addresses) {
+           sources.add(a.trim().toLowerCase());
+        }
+    }
+
+    /**
+     * Creates a ConfigSourceSet containing all the unique given input addresses.
+     * Each address is trimmed and lower-cased before adding.
+     *
+     * @param addresses  Connection endpoints on the format "tcp/host:port".
+     */
+    public ConfigSourceSet(String[] addresses) {
+        this(Arrays.asList(addresses));
+    }
+
+    /**
+     * Convenience constructor to create a ConfigSourceSet with only one input address.
+     *
+     * @param address  Connection endpoint on the format "tcp/host:port".
+     */
+    public ConfigSourceSet(String address) {
+        this(new String[] {address});
+    }
+
+    /**
+     * Returns an unmodifiable set containing all sources in this ConfigSourceSet. Iteration order is
+     * guaranteed to be the same as that of the list or array that was given when this set was created.
+     *
+     * @return All sources in this ConfigSourceSet.
+     */
+    public Set<String> getSources() {
+        return Collections.unmodifiableSet(sources);
+    }
+
+    public boolean equals(Object o) {
+        if (o == this) {
+            return true;
+        }
+        if (! (o instanceof ConfigSourceSet)) {
+            return false;
+        }
+        ConfigSourceSet css = (ConfigSourceSet)o;
+        return sources.equals(css.sources);
+    }
+
+    public int hashCode() {
+        return sources.hashCode();
+    }
+
+    public String toString() {
+        return sources.toString();
+    }
+
+    /**
+     * Create a new source set using the environment variables or system properties
+     * @return a new source set if available, null if not.
+     */
+    public static ConfigSourceSet createDefault() {
+        String configSources = System.getenv("VESPA_CONFIG_SOURCES");
+        if (configSources != null) {
+            log.log(LogLevel.INFO, "Using config sources from VESPA_CONFIG_SOURCES: " + configSources);
+            return new ConfigSourceSet(checkSourcesSyntax(configSources));
+        } else {
+            String[] def = {"tcp/localhost:" + System.getProperty("vespa.config.port", "19090")};
+            String[] sourceSet = checkSourcesSyntax(System.getProperty("configsources"));
+            return new ConfigSourceSet(sourceSet == null ? def : sourceSet);
+        }
+    }
+
+    /**
+     * Check sources syntax and convert it to a proper source set by checking if
+     * sources start with the required "tcp/" prefix and add that prefix if not.
+     *
+     * @param sources a source set as a comma-separated string
+     * @return a String array with sources, or null if the input source set was null
+     */
+    private static String[] checkSourcesSyntax(String sources) {
+        String[] sourceSet = null;
+        if (sources != null) {
+            sourceSet = sources.split(",");
+            int i = 0;
+            for (String s : sourceSet) {
+                if (!s.startsWith("tcp/")) {
+                    sourceSet[i] = "tcp/" + sourceSet[i];
+                }
+                i++;
+            }
+        }
+        return sourceSet;
+    }
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/ConfigSubscriber.java b/config/src/main/java/com/yahoo/config/subscription/ConfigSubscriber.java
new file mode 100644
index 00000000000..2322726057e
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/ConfigSubscriber.java
@@ -0,0 +1,449 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.logging.Logger;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.ConfigurationRuntimeException;
+import com.yahoo.config.subscription.impl.ConfigSubscription;
+import com.yahoo.config.subscription.impl.JRTConfigRequester;
+import com.yahoo.log.LogLevel;
+import com.yahoo.yolean.Exceptions;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.TimingValues;
+
+/**
+ * Used for subscribing to one or more configs. Can optionally be given a {@link ConfigSource} for the configs
+ * that will be used when {@link #subscribe(Class, String)} is called.
+ *
+ * {@link #subscribe(Class, String)} on the configs needed, call {@link #nextConfig(long)} and get the config from the
+ * {@link ConfigHandle} which {@link #subscribe(Class, String)} returned.
+ *
+ * @author vegardh
+ * @since 5.1
+ */
+public class ConfigSubscriber {
+    private Logger log = Logger.getLogger(getClass().getName());
+    private State state = State.OPEN;
+    protected List<ConfigHandle<? extends ConfigInstance>> subscriptionHandles = new ArrayList<>();
+    private final ConfigSource source;
+    private long generation = -1;
+
+    /**
+     * Reuse requesters for equal source sets, limit number if many subscriptions.
+     */
+    protected Map<ConfigSourceSet, JRTConfigRequester> requesters = new HashMap<>();
+
+    /**
+     * The states of the subscriber. Affects the validity of calling certain methods.
+     *
+     */
+    protected enum State {
+        OPEN, FROZEN, CLOSED
+    }
+
+    /**
+     * Constructs a new subscriber. The default Vespa network config source will be used, which is the address of
+     * a config proxy (part of vespa_base) running locally. It can also be changed by setting VESPA_CONFIG_SOURCES.
+     */
+    public ConfigSubscriber() {
+        this(JRTConfigRequester.defaultSourceSet);
+    }
+
+    /**
+     * Constructs a new subscriber with the given source.
+     *
+     * @param source a {@link ConfigSource} that will be used when {@link #subscribe(Class, String)} is called.
+     */
+    public ConfigSubscriber(ConfigSource source) {
+        this.source = source;
+    }
+
+    /**
+     * Subscribes on the given type of {@link ConfigInstance} with the given config id.
+     *
+     * The method blocks until the first config is ready to be fetched with {@link #nextConfig()}.
+     *
+     * @param configClass The class, typically generated from a def-file using config-class-plugin
+     * @param configId Identifies the service in vespa-services.xml, or null if you are using a local {@link ConfigSource} which does not use config id.
+     * Also supported: raw:, file:, dir: or jar: config id which addresses config locally in the same way.
+     *
+     * @return a ConfigHandle
+     */
+    public <T extends ConfigInstance> ConfigHandle<T> subscribe(Class<T> configClass, String configId) {
+        return subscribe(configClass, configId, source, new TimingValues());
+    }
+
+    /**
+     * Subscribes on the given type of {@link ConfigInstance} with the given config id and subscribe timeout.
+     *
+     * The method blocks until the first config is ready to be fetched with {@link #nextConfig()}.
+     *
+     * @param configClass The class, typically generated from a def-file using config-class-plugin
+     * @param configId    Identifies the service in vespa-services.xml, or possibly raw:, file:, dir: or jar: type config which addresses config locally.
+     * @param timeoutMillis The time to wait for a config to become available, in milliseconds
+     * @return a ConfigHandle
+     */
+    public <T extends ConfigInstance> ConfigHandle<T> subscribe(Class<T> configClass, String configId, long timeoutMillis) {
+        return subscribe(configClass, configId, source, new TimingValues().setSubscribeTimeout(timeoutMillis));
+    }
+
+    // for testing
+    <T extends ConfigInstance> ConfigHandle<T> subscribe(Class<T> configClass, String configId, ConfigSource source, TimingValues timingValues) {
+        checkStateBeforeSubscribe();
+        final ConfigKey<T> configKey = new ConfigKey<>(configClass, configId);
+        ConfigSubscription<T> sub = ConfigSubscription.get(configKey, this, source, timingValues);
+        ConfigHandle<T> handle = new ConfigHandle<>(sub);
+        subscribeAndHandleErrors(sub, configKey, handle, timingValues);
+        return handle;
+    }
+
+    protected void checkStateBeforeSubscribe() {
+        if (state != State.OPEN)
+            throw new IllegalStateException("Adding subscription after calling nextConfig() is not allowed");
+    }
+
+    protected void subscribeAndHandleErrors(ConfigSubscription<?> sub, ConfigKey<?> configKey, ConfigHandle<?> handle, TimingValues timingValues) {
+        subscriptionHandles.add(handle);
+        // Must block here until something available from the subscription, so we know that it offers something when the user calls nextConfig
+        boolean subOk = sub.subscribe(timingValues.getSubscribeTimeout());
+        throwIfExceptionSet(sub);
+        if (!subOk) {
+            //sub.close();
+            //subscriptionHandles.remove(handle);
+            throw new ConfigurationRuntimeException("Subscribe for '" + configKey + "' timed out (timeout was " + timingValues.getSubscribeTimeout() + " ms): " + sub);
+        }
+    }
+
+    /**
+     * Use this for waiting for a new config that has changed.
+     *
+     * Returns true if:
+     *
+     * It is the first time nextConfig() is called on this subscriber, and the framework has fetched config for all subscriptions. (Typically a first time config.)
+     *
+     * or
+     *
+     * All configs for the subscriber have a new generation since the last time nextConfig() was called, AND they have the same generation AND there is a change in config for at least one
+     * of the configs. (Typically calls for a reconfig.)
+     *
+     * You can check which configs are changed by calling {@link ConfigHandle#isChanged()} on the handle you got from {@link #subscribe(Class, String)}.
+     *
+     * If the call times out (timeout 1000 ms), no handle will have the changed flag set. You should not configure anything then.
+     *
+     * @return true if a config/reconfig of your system should happen
+     * @throws ConfigInterruptedException if thread performing this call interrupted.
+     */
+    public boolean nextConfig() {
+        return nextConfig(TimingValues.defaultNextConfigTimeout);
+    }
+
+    /**
+     * Use this for waiting for a new config that has changed, with the given timeout.
+     *
+     * Returns true if:
+     *
+     * It is the first time nextConfig() is called on this subscriber, and the framework has fetched config for all subscriptions. (Typically a first time config.)
+     *
+     * or
+     *
+     * All configs for the subscriber have a new generation since the last time nextConfig() was called, AND they have the same generation AND there is a change in config for at least one
+     * of the configs. (Typically calls for a reconfig.)
+     *
+     * You can check which configs are changed by calling {@link ConfigHandle#isChanged()} on the handle you got from {@link #subscribe(Class, String)}.
+     *
+     * If the call times out, no handle will have the changed flag set. You should not configure anything then.
+     *
+     * @param timeoutMillis timeout in milliseconds
+     * @return true if a config/reconfig of your system should happen
+     * @throws ConfigInterruptedException if thread performing this call interrupted.
+     */
+    public boolean nextConfig(long timeoutMillis) {
+        return acquireSnapshot(timeoutMillis, true);
+    }
+
+    /**
+     * Use this for waiting for a new config generation.
+     *
+     * Returns true if:
+     *
+     * It is the first time nextGeneration() is called on this subscriber, and the framework has fetched config for all subscriptions. (Typically a first time config.)
+     *
+     * or
+     *
+     * All configs for the subscriber have a new generation since the last time nextGeneration() was called, AND they have the same generation. Note that
+     * none of the configs have to be changed, but they might be.
+     *
+     *
+     * You can check which configs are changed by calling {@link ConfigHandle#isChanged()} on the handle you got from {@link #subscribe(Class, String)}.
+     *
+     * If the call times out (timeout 1000 ms), no handle will have the changed flag set. You should not configure anything then.
+     *
+     * @return true if generations for all configs have been updated.
+     * @throws ConfigInterruptedException if thread performing this call interrupted.
+     */
+    public boolean nextGeneration() {
+        return nextGeneration(TimingValues.defaultNextConfigTimeout);
+    }
+
+    /**
+     * Use this for waiting for a new config generation, with the given timeout
+     *
+     * Returns true if:
+     *
+     * It is the first time nextGeneration() is called on this subscriber, and the framework has fetched config for all subscriptions. (Typically a first time config.)
+     *
+     * or
+     *
+     * All configs for the subscriber have a new generation since the last time nextGeneration() was called, AND they have the same generation. Note that
+     * none of the configs have to be changed, but they might be.
+     *
+     * You can check which configs are changed by calling {@link ConfigHandle#isChanged()} on the handle you got from {@link #subscribe(Class, String)}.
+     *
+     * If the call times out (timeout 1000 ms), no handle will have the changed flag set. You should not configure anything then.
+     *
+     * @param timeoutMillis timeout in milliseconds
+     * @return true if generations for all configs have been updated.
+     * @throws ConfigInterruptedException if thread performing this call interrupted.
+     */
+    public boolean nextGeneration(long timeoutMillis) {
+        return acquireSnapshot(timeoutMillis, false);
+    }
+
+    /**
+     * Acquire a snapshot of all configs with the same generation within a timeout.
+     * @param timeoutInMillis timeout to wait in milliseconds
+     * @param requireChange if set, at least one config have to change
+     * @return true, if a new config generation has been found for all configs (additionally requires
+     * that at lest one of them has changed if <code>requireChange</code> is true), false otherwise
+     */
+    private boolean acquireSnapshot(long timeoutInMillis, boolean requireChange) {
+        if (state == State.CLOSED) return false;
+        long started = System.currentTimeMillis();
+        long timeLeftMillis = timeoutInMillis;
+        state = State.FROZEN;
+        boolean anyConfigChanged = false;
+        boolean allGenerationsChanged = true;
+        boolean allGenerationsTheSame = true;
+        Long currentGenChecker = null;
+        for (ConfigHandle<? extends ConfigInstance> h : subscriptionHandles) {
+            h.setChanged(false); // Reset this flag, if it was set, the user should have acted on it the last time this method returned true.
+        }
+        boolean reconfigDue;
+        do {
+            // Keep on polling the subscriptions until we have a new generation across the board, or it times out
+            for (ConfigHandle<? extends ConfigInstance> h : subscriptionHandles) {
+                ConfigSubscription<? extends ConfigInstance> subscription = h.subscription();
+                if (!subscription.nextConfig(timeLeftMillis)) {
+                    // This subscriber has no new state and we know it has exhausted all time
+                    return false;
+                }
+                throwIfExceptionSet(subscription);
+                if (currentGenChecker == null) currentGenChecker = subscription.getGeneration();
+                if (!currentGenChecker.equals(subscription.getGeneration())) allGenerationsTheSame = false;
+                allGenerationsChanged = allGenerationsChanged && subscription.isGenerationChanged();
+                if (subscription.isConfigChanged()) anyConfigChanged = true;
+                timeLeftMillis = timeLeftMillis - (System.currentTimeMillis() - started);
+            }
+            reconfigDue = (anyConfigChanged || !requireChange) && allGenerationsChanged && allGenerationsTheSame;
+            if (!reconfigDue && timeLeftMillis > 0) {
+                sleep(10);
+            }
+        } while (!reconfigDue && timeLeftMillis > 0);
+        if (reconfigDue) {
+            // This indicates the clients will possibly reconfigure their services, so "reset" changed-logic in subscriptions.
+            // Also if appropriate update the changed flag on the handler, which clients use.
+            markSubsChangedSeen();
+            generation = subscriptionHandles.get(0).subscription().getGeneration();
+        }
+        return reconfigDue;
+    }
+
+    private void sleep(long i) {
+        try {
+            Thread.sleep(i);
+        } catch (InterruptedException e) {
+            throw new ConfigInterruptedException(e);
+        }
+    }
+
+    /**
+     * If a {@link ConfigSubscription} has its exception set, reset that field and throw it
+     *
+     * @param sub {@link ConfigSubscription}
+     */
+    protected void throwIfExceptionSet(ConfigSubscription<? extends ConfigInstance> sub) {
+        RuntimeException subThrowable = sub.getException();
+        if (subThrowable != null) {
+            sub.setException(null);
+            throw subThrowable;
+        }
+    }
+
+    private void markSubsChangedSeen() {
+        for (ConfigHandle<? extends ConfigInstance> h : subscriptionHandles) {
+            ConfigSubscription<? extends ConfigInstance> sub = h.subscription();
+            h.setChanged(sub.isConfigChanged());
+            sub.resetChangedFlags();
+        }
+    }
+
+    /**
+     * Closes all open {@link ConfigSubscription}s
+     */
+    public void close() {
+        state = State.CLOSED;
+        for (ConfigHandle<? extends ConfigInstance> h : subscriptionHandles) {
+            h.subscription().close();
+        }
+        closeRequesters();
+        log.log(LogLevel.DEBUG, "Config subscriber has been closed.");
+    }
+
+    /**
+     * Closes all open requesters
+     */
+    protected void closeRequesters() {
+        for (JRTConfigRequester requester : requesters.values()) {
+            requester.close();
+        }
+    }
+
+    @Override
+    public String toString() {
+        String ret = "Subscriber state:" + state;
+        for (ConfigHandle<?> h : subscriptionHandles) {
+            ret = ret + "\n" + h.toString();
+        }
+        return ret;
+    }
+
+    /**
+     * Convenience method to start a daemon thread called "Vespa config thread" with the given runnable. If you want the runnable to
+     * handle a {@link ConfigSubscriber} or {@link ConfigHandle} you have declared locally outside, declare them as final to make it work.
+     *
+     * @param runnable a class implementing {@link java.lang.Runnable}
+     * @return the newly started thread
+     */
+    public Thread startConfigThread(Runnable runnable) {
+        Thread t = new Thread(runnable);
+        t.setDaemon(true);
+        t.setName("Vespa config thread");
+        t.start();
+        return t;
+    }
+
+    protected State state() {
+        return state;
+    }
+
+    /**
+     * Sets all subscriptions under this subscriber to have the given generation. This is intended for testing, to emulate a
+     * reload-config operation.
+     *
+     * @param generation a generation number
+     */
+    public void reload(long generation) {
+        for (ConfigHandle<?> h : subscriptionHandles) {
+            h.subscription().reload(generation);
+        }
+    }
+
+    /**
+     * The source used by this subscriber.
+     *
+     * @return the {@link ConfigSource} used by this subscriber
+     */
+    public ConfigSource getSource() {
+        return source;
+    }
+
+    /**
+     * Implementation detail, do not use.
+     * @return requesters
+     */
+    public Map<ConfigSourceSet, JRTConfigRequester> requesters() {
+        return requesters;
+    }
+
+    public boolean isClosed() {
+        return state == State.CLOSED;
+    }
+
+    /**
+     * Use this convenience method if you only want to subscribe on <em>one</em> config, and want generic error handling.
+     * Implement {@link SingleSubscriber} and pass to this method.
+     * You will get initial config, and a config thread will be started. The method will throw in your thread if initial
+     * configuration fails, and the config thread will print a generic error message (but continue) if it fails thereafter. The config
+     * thread will stop if you {@link #close()} this {@link ConfigSubscriber}.
+     *
+     * @param <T> ConfigInstance type
+     * @param singleSubscriber The object to receive config
+     * @param configClass      The class, typically generated from a def-file using config-class-plugin
+     * @param configId         Identifies the service in vespa-services.xml
+     * @return The handle of the config
+     * @see #startConfigThread(Runnable)
+     */
+    public <T extends ConfigInstance> ConfigHandle<T> subscribe(final SingleSubscriber<T> singleSubscriber, Class<T> configClass, String configId) {
+        if (!subscriptionHandles.isEmpty())
+            throw new IllegalStateException("Can not start single-subscription because subscriptions were previously opened on this.");
+        final ConfigHandle<T> handle = subscribe(configClass, configId);
+        if (!nextConfig())
+            throw new ConfigurationRuntimeException("Initial config of " + configClass.getName() + " failed.");
+        singleSubscriber.configure(handle.getConfig());
+        startConfigThread(new Runnable() {
+            @Override
+            public void run() {
+                while (!isClosed()) {
+                    try {
+                        if (nextConfig()) {
+                            if (handle.isChanged()) singleSubscriber.configure(handle.getConfig());
+                        }
+                    } catch (Exception e) {
+                        log.log(LogLevel.ERROR, "Exception from config system, continuing config thread: " + Exceptions.toMessageString(e));
+                    }
+                }
+            }
+        });
+        return handle;
+    }
+
+    /**
+     * The current generation of configs known by this subscriber.
+     *
+     * @return the current generation of configs known by this subscriber
+     */
+    public long getGeneration() {
+        return generation;
+    }
+
+    /**
+     * Convenience interface for clients who only subscribe to one config. Implement this, and pass it to {@link ConfigSubscriber#subscribe(SingleSubscriber, Class, String)}.
+     *
+     * @author vegardh
+     */
+    public interface SingleSubscriber<T extends ConfigInstance> {
+        public void configure(T config);
+    }
+
+    /**
+     * Finalizer to ensure that we do not leak resources on reconfig. Though finalizers are bad,
+     * this is not a performance critical object as it will be deconstructed typically container reconfig.
+     */
+    @Override
+    protected void finalize() throws Throwable {
+        try {
+            if (!isClosed()) {
+                close();
+            }
+        } finally {
+            super.finalize();
+        }
+    }
+
+
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/ConfigURI.java b/config/src/main/java/com/yahoo/config/subscription/ConfigURI.java
new file mode 100644
index 00000000000..c492a04b1f6
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/ConfigURI.java
@@ -0,0 +1,57 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import java.io.File;
+
+import com.yahoo.config.subscription.impl.JRTConfigRequester;
+
+/**
+ * A Config URI is a class that can be used to encapsulate a config source and a config id into one
+ * object to simplify parameter passing.
+ *
+ * @author lulf
+ * @since 5.1
+ */
+public class ConfigURI {
+    private String configId;
+    private ConfigSource source;
+
+    private ConfigURI(String configId, ConfigSource source) {
+        this.configId = configId;
+        this.source = source;
+    }
+
+    public String getConfigId() {
+        return configId;
+    }
+
+    public ConfigSource getSource() {
+        return source;
+    }
+
+    public static ConfigURI createFromId(String configId) {
+        return new ConfigURI(getConfigId(configId), getConfigSource(configId));
+    }
+
+    private static ConfigSource getConfigSource(String configId) {
+        if (configId.startsWith("file:")) {
+            return new FileSource(new File(configId.substring(5)));
+        } else if (configId.startsWith("dir:")) {
+            return new DirSource(new File(configId.substring(4)));
+        } else {
+            return JRTConfigRequester.defaultSourceSet;
+        }
+    }
+
+    private static String getConfigId(String configId) {
+        if (configId.startsWith("file:") || configId.startsWith("dir:")) {
+            return "";
+        } else {
+            return configId;
+        }
+    }
+
+    public static ConfigURI createFromIdAndSource(String configId, ConfigSource source) {
+        return new ConfigURI(configId, source);
+    }
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/DirSource.java b/config/src/main/java/com/yahoo/config/subscription/DirSource.java
new file mode 100644
index 00000000000..d9e425022f0
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/DirSource.java
@@ -0,0 +1,24 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import java.io.File;
+
+/**
+ * Source specifying config from a local directory
+ * @author vegardh
+ * @since 5.1
+ *
+ */
+public class DirSource implements ConfigSource {
+    private final File dir;
+
+    public DirSource(File dir) {
+        if (!dir.isDirectory()) throw new IllegalArgumentException("Not a directory: "+dir);
+        this.dir = dir;
+    }
+
+    public File getDir() {
+        return dir;
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/FileSource.java b/config/src/main/java/com/yahoo/config/subscription/FileSource.java
new file mode 100644
index 00000000000..d7634a000b6
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/FileSource.java
@@ -0,0 +1,24 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import java.io.File;
+
+/**
+ * Source specifying config from one local file
+ * @author vegardh
+ * @since 5.1
+ *
+ */
+public class FileSource implements ConfigSource {
+    private final File file;
+
+    public FileSource(File file) {
+        if (!file.isFile()) throw new IllegalArgumentException("Not an ordinary file: "+file);
+        this.file = file;
+    }
+
+    public File getFile() {
+        return file;
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/JarSource.java b/config/src/main/java/com/yahoo/config/subscription/JarSource.java
new file mode 100644
index 00000000000..021b3e72025
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/JarSource.java
@@ -0,0 +1,34 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import java.util.jar.JarFile;
+
+/**
+ * Source specifying config as a jar file entry
+ * @author vegardh
+ * @since 5.1
+ *
+ */
+public class JarSource implements ConfigSource {
+    private final String path;
+    private final JarFile jarFile;
+
+    /**
+     * Creates a new jar source
+     * @param jarFile the jar file to use as a source
+     * @param path the path within the jar file, or null to use the default config/
+     */
+    public JarSource(JarFile jarFile, String path) {
+        this.path = path;
+        this.jarFile = jarFile;
+    }
+
+    public JarFile getJarFile() {
+        return jarFile;
+    }
+
+    public String getPath() {
+        return path;
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/RawSource.java b/config/src/main/java/com/yahoo/config/subscription/RawSource.java
new file mode 100644
index 00000000000..74b3d508652
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/RawSource.java
@@ -0,0 +1,21 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+/**
+ * Source specifying raw config, where payload is given programmatically
+ * @author vegardh
+ * @since 5.1
+ *
+ */
+public class RawSource implements ConfigSource {
+    public final String payload;
+
+    /**
+     * New source with the given payload on Vespa cfg format
+     * @param payload config payload
+     */
+    public RawSource(String payload) {
+        this.payload = payload;
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/impl/ConfigSetSubscription.java b/config/src/main/java/com/yahoo/config/subscription/impl/ConfigSetSubscription.java
new file mode 100644
index 00000000000..3778ee38d98
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/impl/ConfigSetSubscription.java
@@ -0,0 +1,89 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription.impl;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.subscription.ConfigSet;
+import com.yahoo.config.subscription.ConfigSource;
+import com.yahoo.config.subscription.ConfigSubscriber;
+import com.yahoo.vespa.config.ConfigKey;
+
+import java.lang.reflect.Constructor;
+
+/**
+ * Subscription on a programmatically built set of configs
+ * @author vegardh
+ * @since 5.1
+ */
+public class ConfigSetSubscription<T extends ConfigInstance> extends ConfigSubscription<T> {
+
+    private final ConfigSet set;
+    private final ConfigKey<T> subKey;
+
+    ConfigSetSubscription(ConfigKey<T> key,
+            ConfigSubscriber subscriber, ConfigSource cset) {
+        super(key, subscriber);
+        if (!(cset instanceof ConfigSet)) throw new IllegalArgumentException("Source is not a ConfigSet: "+cset);
+        this.set=(ConfigSet) cset;
+        subKey = new ConfigKey<T>(configClass, key.getConfigId());
+        if (!set.contains(subKey)) {
+            throw new IllegalArgumentException("The given ConfigSet "+set+" does not contain a config for "+subKey);
+        }
+        setGeneration(0l);
+    }
+
+    @Override
+    public boolean nextConfig(long timeout) {
+        long end = System.currentTimeMillis() + timeout;
+        do {
+            ConfigInstance myInstance = getNewInstance();
+            // User forced reload
+            if (checkReloaded()) {
+                updateInstance(myInstance);
+                return true;
+            }
+            if (!myInstance.equals(config)) {
+                generation++;
+                updateInstance(myInstance);
+                return true;
+            }
+            sleep(10);
+        } while (System.currentTimeMillis() < end);
+        // These shouldn't be checked anywhere since we return false now, but setting them still
+        setGenerationChanged(false);
+        setConfigChanged(false);
+        return false;
+    }
+
+    private void sleep(int milliSecondsToSleep) {
+        try {
+            Thread.sleep(milliSecondsToSleep);
+        } catch (InterruptedException e) {
+            throw new RuntimeException("nextConfig aborted", e);
+        }
+    }
+
+    @SuppressWarnings("unchecked")
+    private void updateInstance(ConfigInstance myInstance) {
+        if (!myInstance.equals(config)) {
+            setConfigChanged(true);
+        }
+        setConfig((T) myInstance);
+        setGenerationChanged(true);
+    }
+
+    @Override
+    public boolean subscribe(long timeout) {
+        return true;
+    }
+
+    public ConfigInstance getNewInstance() {
+        try {
+            ConfigInstance.Builder builder = set.get(subKey);
+            Constructor<?> constructor = builder.getClass().getDeclaringClass().getConstructor(builder.getClass());
+            return (ConfigInstance) constructor.newInstance(builder);
+        } catch (Exception e) {
+            e.printStackTrace();
+            throw new RuntimeException(e);
+        }
+    }
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/impl/ConfigSubscription.java b/config/src/main/java/com/yahoo/config/subscription/impl/ConfigSubscription.java
new file mode 100644
index 00000000000..0909dc6e1a2
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/impl/ConfigSubscription.java
@@ -0,0 +1,310 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription.impl;
+
+import java.io.File;
+import java.util.logging.Logger;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.subscription.ConfigSet;
+import com.yahoo.config.subscription.ConfigSource;
+import com.yahoo.config.subscription.ConfigSourceSet;
+import com.yahoo.config.subscription.ConfigSubscriber;
+import com.yahoo.config.subscription.DirSource;
+import com.yahoo.config.subscription.FileSource;
+import com.yahoo.config.subscription.JarSource;
+import com.yahoo.config.subscription.RawSource;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.TimingValues;
+import com.yahoo.vespa.config.protocol.DefContent;
+
+/**
+ * Represents one active subscription to one config
+ *
+ * @author vegardh
+ * @since 5.1
+ */
+public abstract class ConfigSubscription<T extends ConfigInstance> {
+    protected static Logger log = Logger.getLogger(ConfigSubscription.class.getName());
+    protected ConfigSubscriber subscriber;
+    protected boolean configChanged = false;
+    protected boolean generationChanged = false;
+    protected volatile T config = null;
+    protected Long generation = null;
+    protected ConfigKey<T> key;
+    protected Class<T> configClass;
+    private volatile RuntimeException exception = null;
+    private State state = State.OPEN;
+    /**
+     * If non-null: The user has set this generation explicitly. nextConfig should take this into account.
+     * Access to these variables _must_ be synchronized, as nextConfig and reload() is likely to be run from
+     * independent threads.
+     */
+    private boolean doReload = false;
+    private long reloadedGeneration = -1;
+
+    enum State {
+        OPEN, CLOSED
+    }
+
+    /**
+     * Initializes one subscription
+     *
+     * @param key a {@link ConfigKey}
+     * @param subscriber the subscriber for this subscription
+     */
+    ConfigSubscription(ConfigKey<T> key, ConfigSubscriber subscriber) {
+        this.key = key;
+        this.configClass = key.getConfigClass();
+        this.subscriber = subscriber;
+    }
+
+
+    /**
+     * Correct type of ConfigSubscription instance based on type of source or form of config id
+     *
+     * @param key a {@link ConfigKey}
+     * @param subscriber the subscriber for this subscription
+     * @return a subclass of a ConfigsSubscription
+     */
+    public static <T extends ConfigInstance> ConfigSubscription<T> get(ConfigKey<T> key, ConfigSubscriber subscriber, ConfigSource source, TimingValues timingValues) {
+        String configId = key.getConfigId();
+        if (source instanceof RawSource || configId.startsWith("raw:")) return getRawSub(key, subscriber, source);
+        if (source instanceof FileSource || configId.startsWith("file:")) return getFileSub(key, subscriber, source);
+        if (source instanceof DirSource || configId.startsWith("dir:")) return getDirFileSub(key, subscriber, source);
+        if (source instanceof JarSource || configId.startsWith("jar:")) return getJarSub(key, subscriber, source);
+        if (source instanceof ConfigSet) return new ConfigSetSubscription<>(key, subscriber, source);
+        if (source instanceof ConfigSourceSet) return new JRTConfigSubscription<>(key, subscriber, source, timingValues);
+        throw new IllegalArgumentException("Unknown source type: "+source);
+    }
+
+    private static <T extends ConfigInstance> JarConfigSubscription<T> getJarSub(
+            ConfigKey<T> key, ConfigSubscriber subscriber, ConfigSource source) {
+        String jarName;
+        String path="config/";
+        if (source instanceof JarSource) {
+            JarSource js = (JarSource) source;
+            jarName=js.getJarFile().getName();
+            if (js.getPath()!=null) path=js.getPath();
+        } else {
+            jarName=key.getConfigId().replace("jar:", "").replaceFirst("\\!/.*", "");
+            if (key.getConfigId().contains("!/")) path = key.getConfigId().replaceFirst(".*\\!/", "");
+        }
+        return new JarConfigSubscription<>(key, subscriber, jarName, path);
+    }
+
+    private static <T extends ConfigInstance> ConfigSubscription<T> getFileSub(
+            ConfigKey<T> key, ConfigSubscriber subscriber, ConfigSource source) {
+        File file = ((source instanceof FileSource))?((FileSource)source).getFile():new File(key.getConfigId().replace("file:", ""));
+        return new FileConfigSubscription<>(key, subscriber, file);
+    }
+
+    private static <T extends ConfigInstance> ConfigSubscription<T> getRawSub(
+            ConfigKey<T> key, ConfigSubscriber subscriber, ConfigSource source) {
+        String payload = ((source instanceof RawSource)?((RawSource)source).payload:key.getConfigId().replace("raw:", ""));
+        return new RawConfigSubscription<>(key, subscriber,payload);
+    }
+
+    private static <T extends ConfigInstance> ConfigSubscription<T> getDirFileSub(ConfigKey<T> key, ConfigSubscriber subscriber, ConfigSource source) {
+        String dir = key.getConfigId().replace("dir:", "");
+        if (source instanceof DirSource) {
+            dir = ((DirSource)source).getDir().toString();
+        }
+        if (!dir.endsWith(File.separator)) dir = dir + File.separator;
+        String name = getConfigFilenameNoVersion(key);
+        File file = new File(dir + name);
+        if (!file.exists()) {
+            throw new IllegalArgumentException("Could not find a config file for '" + key.getName() + "' in '" + dir + "'");
+        }
+        return new FileConfigSubscription<>(key, subscriber, file);
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public boolean equals(Object o) {
+        if (o instanceof ConfigSubscription) {
+            ConfigSubscription<T> other = (ConfigSubscription<T>) o;
+            return key.equals(other.key) &&
+                    subscriber.equals(other.subscriber);
+        }
+        return false;
+    }
+
+    void setConfigChanged(boolean changed) {
+        this.configChanged = changed;
+    }
+
+    void setGenerationChanged(boolean genChanged) {
+        this.generationChanged = genChanged;
+    }
+
+    /**
+     * Called from {@link ConfigSubscriber} when the changed status of this config is propagated to the clients
+     */
+    public void resetChangedFlags() {
+        setConfigChanged(false);
+        setGenerationChanged(false);
+    }
+
+    public boolean isConfigChanged() {
+        return configChanged;
+    }
+
+    public boolean isGenerationChanged() {
+        return generationChanged;
+    }
+
+    void setConfig(T config) {
+        this.config = config;
+    }
+
+    /**
+     * The config object of this subscription
+     *
+     * @return the ConfigInstance (the config) of this subscription
+     */
+    public T getConfig() {
+        return config;
+    }
+
+    /**
+     * The generation of this subscription
+     *
+     * @return the generation of this subscription
+     */
+    public Long getGeneration() {
+        return generation;
+    }
+
+    /**
+     * The class of the subscription's desired {@link ConfigInstance}
+     * @return the config class
+     */
+    public Class<T> getConfigClass() {
+        return configClass;
+    }
+
+    void setGeneration(Long generation) {
+        this.generation = generation;
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder s = new StringBuilder(key.toString());
+        s.append(", Current generation: ").append(generation)
+                .append(", Generation changed: ").append(generationChanged)
+                .append(", Config changed: ").append(configChanged);
+        if (exception != null)
+            s.append(", Exception: ").append(exception);
+        return s.toString();
+    }
+
+    /**
+     * The config key which this subscription uses to identify its config
+     *
+     * @return the ConfigKey for this subscription
+     */
+    public ConfigKey<T> getKey() {
+        return key;
+    }
+
+    /**
+     * Polls this subscription for a change. The method is guaranteed to use all of the given timeout before returning false. It will also take into account a user-set generation,
+     * that can be set by {@link ConfigSubscriber#reload(long)}.
+     *
+     * @param timeout in milliseconds
+     * @return false if timed out, true if the state of {@link #configChanged}, {@link #generationChanged} or {@link #exception} changed. If true, the {@link #config} field will be set also.
+     *         has changed
+     */
+    public abstract boolean nextConfig(long timeout);
+
+    /**
+     * Will block until the next {@link #nextConfig(long)} is guaranteed to return an answer (or throw) immediately (i.e. not block)
+     *
+     * @param timeout in milliseconds
+     * @return false if timed out
+     */
+    public abstract boolean subscribe(long timeout);
+
+    /**
+     * Called by for example network threads to signal that the user thread should throw this exception immediately
+     *
+     * @param e a RuntimeException
+     */
+    public void setException(RuntimeException e) {
+        this.exception = e;
+    }
+
+    /**
+     * Gets an exception set by for example a network thread. If not null, it indicates that it should be
+     * thrown in the user's thread immediately.
+     *
+     * @return a RuntimeException if there exists one
+     */
+    public RuntimeException getException() {
+        return exception;
+    }
+
+    /**
+     * Returns true if an exception set by for example a network thread has been caught.
+     *
+     * @return true if there exists an exception for this subscription
+     */
+    boolean hasException() {
+        return exception != null;
+    }
+
+    public void close() {
+        state = State.CLOSED;
+    }
+
+    State getState() {
+        return state;
+    }
+
+    /**
+     * Returns the file name corresponding to the given key's defName and version.
+     *
+     * @param key a {@link ConfigKey}
+     * @return file name with version number.
+     */
+    static <T extends ConfigInstance> String getConfigFilenameNoVersion(ConfigKey<T> key) {
+        StringBuilder filename = new StringBuilder(key.getName());
+        filename.append(".cfg");
+        return filename.toString();
+    }
+
+    /**
+     * Force this into the given generation, used in testing
+     * @param generation a config generation
+     */
+    public synchronized void reload(long generation) {
+        this.doReload = true;
+        this.reloadedGeneration = generation;
+    }
+
+    /**
+     * True if someone has set the {@link #reloadedGeneration} number by calling {@link #reload(long)}
+     * and hence wants to force a given generation programmatically. If that is the case,
+     * sets the {@link #generation} and {@link #generationChanged} fields accordingly.
+     * @return true if {@link #reload(long)} has been called, false otherwise
+     */
+    protected synchronized boolean checkReloaded() {
+        if (doReload) {
+            // User has called reload
+            generation = reloadedGeneration;
+            setGenerationChanged(true);
+            doReload = false;
+            return true;
+        }
+        return false;
+    }
+
+    /**
+     * The config definition schema
+     *
+     * @return the config definition for this subscription
+     */
+    public DefContent getDefContent() {
+        return (DefContent.fromClass(configClass));
+    }
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/impl/FileConfigSubscription.java b/config/src/main/java/com/yahoo/config/subscription/impl/FileConfigSubscription.java
new file mode 100644
index 00000000000..c1b1e3daaff
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/impl/FileConfigSubscription.java
@@ -0,0 +1,83 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription.impl;
+
+import java.io.File;
+import java.io.IOException;
+import java.util.Arrays;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.ConfigurationRuntimeException;
+import com.yahoo.config.subscription.CfgConfigPayloadBuilder;
+import com.yahoo.config.subscription.ConfigInterruptedException;
+import com.yahoo.config.subscription.ConfigSubscriber;
+import com.yahoo.io.IOUtils;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.ConfigPayload;
+import com.yahoo.log.LogLevel;
+
+/**
+ * Subscription used when config id is file:...
+ * @author vegardh
+ * @since 5.1
+ *
+ */
+public class FileConfigSubscription<T extends ConfigInstance> extends ConfigSubscription<T> {
+
+    final File file;
+    long ts;
+
+    FileConfigSubscription(ConfigKey<T> key, ConfigSubscriber subscriber, File f) {
+        super(key, subscriber);
+        setGeneration(0l);
+        file=f;
+        if (!file.exists() && !file.isFile())
+            throw new IllegalArgumentException("Not a file: "+file);
+    }
+
+    @Override
+    public boolean nextConfig(long timeout) {
+        if (!file.exists() && !file.isFile()) throw new IllegalArgumentException("Not a file: "+file);
+        if (checkReloaded()) {
+            // TODO: Temporary log messages for debugging.
+            log.log(LogLevel.INFO, "User forced config reload at " + System.currentTimeMillis());
+            // User forced reload
+            updateConfig();
+            log.log(LogLevel.INFO, "Config updated at " + System.currentTimeMillis() + ", changed: " + isConfigChanged());
+            log.log(LogLevel.INFO, "Config: " + config.toString());
+            return true;
+        }
+        if (file.lastModified()!=ts) {
+            updateConfig();
+            generation++;
+            setGenerationChanged(true);
+            return true;
+        }
+        try {
+            Thread.sleep(timeout);
+        } catch (InterruptedException e) {
+            throw new ConfigInterruptedException(e);
+        }
+        // These shouldn't be checked anywhere since we return false now, but setting them still
+        setGenerationChanged(false);
+        setConfigChanged(false);
+        return false;
+    }
+
+    private void updateConfig() {
+        ts=file.lastModified();
+        ConfigInstance prev = config;
+        try {
+            ConfigPayload payload = new CfgConfigPayloadBuilder().deserialize(Arrays.asList(IOUtils.readFile(file).split("\n")));
+            config = payload.toInstance(configClass, key.getConfigId());
+        } catch (IOException e) {
+            throw new ConfigurationRuntimeException(e);
+        }
+        setConfigChanged(!config.equals(prev));
+    }
+
+    @Override
+    public boolean subscribe(long timeout) {
+        return true;
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/impl/GenericConfigHandle.java b/config/src/main/java/com/yahoo/config/subscription/impl/GenericConfigHandle.java
new file mode 100644
index 00000000000..26963428914
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/impl/GenericConfigHandle.java
@@ -0,0 +1,25 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription.impl;
+
+import com.yahoo.config.subscription.ConfigHandle;
+import com.yahoo.vespa.config.RawConfig;
+
+/**
+ * A config handle which does not use the config class, but payload instead. To be used in proxy?
+ *
+ * @author vegardh
+ */
+@SuppressWarnings({"rawtypes", "unchecked"})
+public class GenericConfigHandle extends ConfigHandle {
+
+    private final GenericJRTConfigSubscription genSub;
+
+    public GenericConfigHandle(GenericJRTConfigSubscription sub) {
+        super(sub);
+        genSub = sub;
+    }
+
+    public RawConfig getRawConfig() {
+        return genSub.getRawConfig();
+    }
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/impl/GenericConfigSubscriber.java b/config/src/main/java/com/yahoo/config/subscription/impl/GenericConfigSubscriber.java
new file mode 100644
index 00000000000..5a155e42aca
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/impl/GenericConfigSubscriber.java
@@ -0,0 +1,74 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription.impl;
+
+import java.util.List;
+import java.util.Map;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.subscription.ConfigHandle;
+import com.yahoo.config.subscription.ConfigSource;
+import com.yahoo.config.subscription.ConfigSourceSet;
+import com.yahoo.config.subscription.ConfigSubscriber;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.TimingValues;
+
+/**
+ * A subscriber that can subscribe without the class. Used by configproxy.
+ *
+ * @author vegardh
+ */
+public class GenericConfigSubscriber extends ConfigSubscriber {
+    /**
+     * Constructs a new subscriber using the given pool of requesters (JRTConfigRequester holds 1 connection which in
+     * turn is subject to failover across the elems in the source set.)
+     * The behaviour is undefined if the map key is different from the source set the requester was built with.
+     * See also {@link JRTConfigRequester#get(com.yahoo.vespa.config.ConnectionPool, com.yahoo.vespa.config.TimingValues)}
+     *
+     * @param requesters a map from config source set to config requester
+     */
+    public GenericConfigSubscriber(Map<ConfigSourceSet, JRTConfigRequester> requesters) {
+        this.requesters = requesters;
+    }
+
+    public GenericConfigSubscriber() {
+        super();
+    }
+
+    /**
+     * Subscribes to config without using the class. For internal use in config proxy.
+     *
+     * @param key the {@link ConfigKey to subscribe to}
+     * @param defContent the config definition content for the config to subscribe to
+     * @param source the config source to use
+     * @param timingValues {@link TimingValues}
+     * @return generic handle
+     */
+    public GenericConfigHandle subscribe(ConfigKey<?> key, List<String> defContent, ConfigSource source, TimingValues timingValues) {
+        checkStateBeforeSubscribe();
+        GenericJRTConfigSubscription sub = new GenericJRTConfigSubscription(key, defContent, this, source, timingValues);
+        GenericConfigHandle handle = new GenericConfigHandle(sub);
+        subscribeAndHandleErrors(sub, key, handle, timingValues);
+        return handle;
+    }
+
+    @Override
+    public <T extends ConfigInstance> ConfigHandle<T> subscribe(Class<T> configClass, String configId) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public <T extends ConfigInstance> ConfigHandle<T> subscribe(Class<T> configClass, String configId, long timeoutMillis) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public <T extends ConfigInstance> ConfigHandle<T> subscribe(SingleSubscriber<T> singleSubscriber, Class<T> configClass, String configId) {
+        throw new UnsupportedOperationException();
+    }
+
+    /**
+     * Do nothing, since we share requesters
+     */
+    public void closeRequesters() {
+    }
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/impl/GenericJRTConfigSubscription.java b/config/src/main/java/com/yahoo/config/subscription/impl/GenericJRTConfigSubscription.java
new file mode 100644
index 00000000000..5e88e86be71
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/impl/GenericJRTConfigSubscription.java
@@ -0,0 +1,74 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription.impl;
+
+import java.util.List;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.subscription.ConfigSource;
+import com.yahoo.config.subscription.ConfigSubscriber;
+import com.yahoo.log.LogLevel;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.RawConfig;
+import com.yahoo.vespa.config.TimingValues;
+import com.yahoo.vespa.config.protocol.DefContent;
+import com.yahoo.vespa.config.protocol.JRTClientConfigRequest;
+
+/**
+ * A JRT subscription which does not use the config class, but {@link com.yahoo.vespa.config.RawConfig} instead.
+ * Used by config proxy.
+ * @author vegardh
+ *
+ */
+@SuppressWarnings("rawtypes")
+public class GenericJRTConfigSubscription extends JRTConfigSubscription {
+
+    private RawConfig config;
+    private final List<String> defContent;
+
+    @SuppressWarnings("unchecked")
+    public GenericJRTConfigSubscription(ConfigKey<?> key,
+                                        List<String> defContent,
+            ConfigSubscriber subscriber,
+            ConfigSource source,
+            TimingValues timingValues) {
+        super(key, subscriber, source, timingValues);
+        this.defContent = defContent;
+    }
+
+    @Override
+    protected void setNewConfig(JRTClientConfigRequest jrtReq) {
+        this.config = RawConfig.createFromResponseParameters(jrtReq);
+        if (log.isLoggable(LogLevel.DEBUG)) {
+            log.log(LogLevel.DEBUG, "in setNewConfig, config=" + this.config);
+        }
+    }
+
+    // This method is overridden because config needs to have its generation
+    // updated if _only_ generation has changed
+    @Override
+    void setGeneration(Long generation) {
+        super.setGeneration(generation);
+        if (this.config != null) {
+            this.config.setGeneration(generation);
+        }
+    }
+
+    public RawConfig getRawConfig() {
+        return config;
+    }
+
+    /**
+     * The config definition schema
+     *
+     * @return the config definition for this subscription
+     */
+    @Override
+    public DefContent getDefContent() {
+        return (DefContent.fromList(defContent));
+    }
+
+    @Override
+    public ConfigInstance getConfig() {
+        return null;
+    }
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/impl/JRTConfigRequester.java b/config/src/main/java/com/yahoo/config/subscription/impl/JRTConfigRequester.java
new file mode 100644
index 00000000000..2e2e71989a5
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/impl/JRTConfigRequester.java
@@ -0,0 +1,362 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription.impl;
+
+import java.text.SimpleDateFormat;
+import java.util.TimeZone;
+import java.util.concurrent.Executors;
+import java.util.concurrent.ScheduledThreadPoolExecutor;
+import java.util.concurrent.ThreadFactory;
+import java.util.concurrent.TimeUnit;
+import java.util.logging.Level;
+import java.util.logging.Logger;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.ConfigurationRuntimeException;
+import com.yahoo.config.subscription.ConfigSourceSet;
+import com.yahoo.jrt.Request;
+import com.yahoo.jrt.RequestWaiter;
+import com.yahoo.log.LogLevel;
+import com.yahoo.vespa.config.protocol.JRTClientConfigRequest;
+import com.yahoo.yolean.Exceptions;
+import com.yahoo.vespa.config.*;
+import com.yahoo.vespa.config.protocol.JRTConfigRequestFactory;
+import com.yahoo.vespa.config.protocol.Trace;
+
+/**
+ * This class fetches config payload using JRT, and acts as the callback target.
+ * It uses the {@link JRTConfigSubscription} and {@link JRTClientConfigRequest}
+ * as context, and puts the requests objects on a queue on the subscription,
+ * for handling by the user thread.
+ *
+ * @author vegardh
+ * @since 5.1
+ */
+// Note: this is similar to old JRTSource
+public class JRTConfigRequester implements RequestWaiter {
+    private static final Logger log = Logger.getLogger(JRTConfigRequester.class.getName());
+    public static final ConfigSourceSet defaultSourceSet = ConfigSourceSet.createDefault();
+    private static final int TRACELEVEL = 6;
+    private final TimingValues timingValues;
+    private int fatalFailures = 0; // independent of transientFailures
+    private int transientFailures = 0;  // independent of fatalFailures
+    private final ScheduledThreadPoolExecutor scheduler = new ScheduledThreadPoolExecutor(1, new JRTSourceThreadFactory());
+    private long suspendWarned;
+    private long noApplicationWarned;
+    private static final long delayBetweenWarnings = 60000; //ms
+    private final ConnectionPool connectionPool;
+    static final float randomFraction = 0.2f;
+    /* Time to be added to server timeout to create client timeout. This is the time allowed for the server to respond after serverTimeout has elapsed. */
+    private static final Double additionalTimeForClientTimeout = 5.0;
+
+    private static final SimpleDateFormat yyyyMMddz;
+
+    static {
+        yyyyMMddz = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss z");
+        yyyyMMddz.setTimeZone(TimeZone.getTimeZone("GMT"));
+    }
+
+    /**
+     * Returns a new requester
+     * @param connectionPool The connectionPool to use
+     * @param timingValues The timing values
+     * @return new requester object
+     */
+    public static JRTConfigRequester get(ConnectionPool connectionPool, TimingValues timingValues) {
+        return new JRTConfigRequester(connectionPool, timingValues);
+    }
+
+    /**
+     * New requester
+     *  @param connectionPool the connectionPool this requester should use
+     * @param timingValues timeouts and delays used when sending JRT config requests
+     */
+    JRTConfigRequester(ConnectionPool connectionPool, TimingValues timingValues) {
+        this.connectionPool = connectionPool;
+        this.timingValues = timingValues;
+    }
+
+    /**
+     * Requests the config for the {@link com.yahoo.config.ConfigInstance} on the given {@link ConfigSubscription}
+     *
+     * @param sub a subscription
+     */
+    public <T extends ConfigInstance> void request(JRTConfigSubscription<T> sub) {
+        JRTClientConfigRequest req = JRTConfigRequestFactory.createFromSub(sub);
+        doRequest(sub, req, timingValues.getSubscribeTimeout());
+    }
+
+    private <T extends ConfigInstance> void doRequest(JRTConfigSubscription<T> sub,
+                                                      JRTClientConfigRequest req, long timeout) {
+        com.yahoo.vespa.config.Connection connection = connectionPool.getCurrent();
+        req.getRequest().setContext(new RequestContext(sub, req, connection));
+        boolean reqOK = req.validateParameters();
+        if (!reqOK) throw new ConfigurationRuntimeException("Error in parameters for config request: " + req);
+        // Add some time to the timeout, we never want it to time out in JRT during normal operation
+        double jrtClientTimeout = getClientTimeout(timeout);
+        if (log.isLoggable(LogLevel.DEBUG)) {
+            log.log(LogLevel.DEBUG, "Requesting config for " + sub + " on connection " + connection + " with RPC timeout " + jrtClientTimeout + ",defcontent=" +
+                    req.getDefContent().asString());
+        }
+        connection.invokeAsync(req.getRequest(), jrtClientTimeout, this);
+    }
+
+    @SuppressWarnings("unchecked")
+    @Override
+    public void handleRequestDone(Request req) {
+        JRTConfigSubscription<ConfigInstance> sub = null;
+        try {
+            RequestContext context = (RequestContext) req.getContext();
+            sub = context.sub;
+            doHandle(sub, context.jrtReq, context.connection);
+        } catch (RuntimeException e) {
+            if (sub != null) {
+                // Sets this field, it will get thrown from the user thread
+                sub.setException(e);
+            } else {
+                // Very unlikely
+                log.log(Level.SEVERE, "Failed to get subscription object from JRT config callback: " +
+                        Exceptions.toMessageString(e));
+            }
+        }
+    }
+
+    protected void doHandle(JRTConfigSubscription<ConfigInstance> sub, JRTClientConfigRequest jrtReq, Connection connection) {
+        if (sub.getState() == ConfigSubscription.State.CLOSED) return; // Avoid error messages etc. after closing
+        boolean validResponse = jrtReq.validateResponse();
+        Trace trace = jrtReq.getResponseTrace();
+        trace.trace(TRACELEVEL, "JRTConfigRequester.doHandle()");
+        if (log.isLoggable(LogLevel.DEBUG)) {
+            log.log(LogLevel.DEBUG, trace.toString());
+        }
+        if (validResponse) {
+            if (log.isLoggable(LogLevel.DEBUG)) {
+                log.log(LogLevel.DEBUG, "Request callback, OK. Req: " + jrtReq + "\nSpec: " + connection);
+            }
+            handleOKRequest(jrtReq, sub, connection);
+        } else {
+            logWhenErrorResponse(jrtReq, connection);
+            handleFailedRequest(jrtReq, sub, connection);
+        }
+    }
+
+    private void logWhenErrorResponse(JRTClientConfigRequest jrtReq, Connection connection) {
+        switch (jrtReq.errorCode()) {
+            case com.yahoo.jrt.ErrorCode.CONNECTION:
+                log.log(LogLevel.DEBUG, "Request callback failed: " + jrtReq.errorMessage() +
+                        "\nConnection spec: " + connection);
+                break;
+            case ErrorCode.APPLICATION_NOT_LOADED:
+            case ErrorCode.UNKNOWN_VESPA_VERSION:
+                final long now = System.currentTimeMillis();
+                if (noApplicationWarned < (now - delayBetweenWarnings)) {
+                    log.log(LogLevel.WARNING, "Request callback failed: " + ErrorCode.getName(jrtReq.errorCode()) +
+                            ". Connection spec: " + connection.getAddress());
+                    noApplicationWarned = now;
+                }
+                break;
+            default:
+                log.log(LogLevel.WARNING, "Request callback failed. Req: " + jrtReq + "\nSpec: " + connection.getAddress() +
+                        " . Req error message: " + jrtReq.errorMessage());
+                break;
+        }
+    }
+
+    private void handleFailedRequest(JRTClientConfigRequest jrtReq, JRTConfigSubscription<ConfigInstance> sub, Connection connection) {
+        final boolean configured = (sub.getConfig() != null);
+        if (configured) {
+            // The subscription object has an "old" config, which is all we have to offer back now
+            log.log(LogLevel.INFO, "Failure of config subscription, clients will keep existing config until resolved: " + sub);
+        }
+        final ErrorType errorType = ErrorType.getErrorType(jrtReq.errorCode());
+        connectionPool.setError(connection, jrtReq.errorCode());
+        long delay = calculateFailedRequestDelay(errorType, transientFailures, fatalFailures, timingValues, configured);
+        if (errorType == ErrorType.TRANSIENT) {
+            handleTransientlyFailed(jrtReq, sub, delay, connection);
+        } else {
+            handleFatallyFailed(jrtReq, sub, delay);
+        }
+    }
+
+    static long calculateFailedRequestDelay(ErrorType errorCode, int transientFailures, int fatalFailures,
+                                            TimingValues timingValues, boolean configured) {
+        long delay;
+        if (configured)
+            delay = timingValues.getConfiguredErrorDelay();
+        else
+            delay = timingValues.getUnconfiguredDelay();
+        if (errorCode == ErrorType.TRANSIENT) {
+            delay = delay * Math.min((transientFailures + 1), timingValues.getMaxDelayMultiplier());
+        } else {
+            delay = timingValues.getFixedDelay() + (delay * Math.min(fatalFailures, timingValues.getMaxDelayMultiplier()));
+            delay = timingValues.getPlusMinusFractionRandom(delay, randomFraction);
+        }
+        return delay;
+    }
+
+    private void handleTransientlyFailed(JRTClientConfigRequest jrtReq,
+                                         JRTConfigSubscription<ConfigInstance> sub,
+                                         long delay,
+                                         Connection connection) {
+        long now = System.currentTimeMillis();
+        transientFailures++;
+        if (suspendWarned < (now - delayBetweenWarnings)) {
+            log.log(LogLevel.INFO, "Connection to " + connection.getAddress() +
+                    " failed or timed out, clients will keep existing config, will keep trying.");
+            suspendWarned = now;
+        }
+        if (sub.getState() != ConfigSubscription.State.OPEN) return;
+        scheduleNextRequest(jrtReq, sub, delay, calculateErrorTimeout());
+    }
+
+    private long calculateErrorTimeout() {
+        return timingValues.getPlusMinusFractionRandom(timingValues.getErrorTimeout(), randomFraction);
+    }
+
+    /**
+     * This handles a fatal error both in the case that the subscriber is configured and not.
+     * The difference is in the delay (passed from outside) and the log level used for
+     * error message.
+     *
+     * @param jrtReq a JRT config request
+     * @param sub    a config subscription
+     * @param delay  delay before sending a new request
+     */
+    private void handleFatallyFailed(JRTClientConfigRequest jrtReq,
+                                     JRTConfigSubscription<ConfigInstance> sub, long delay) {
+        if (sub.getState() != ConfigSubscription.State.OPEN) return;
+        fatalFailures++;
+        // The logging depends on whether we are configured or not.
+        Level logLevel = sub.getConfig() == null ? LogLevel.DEBUG : LogLevel.INFO;
+        String logMessage = "Request for config " + jrtReq.getShortDescription() + "' failed with error code " +
+                jrtReq.errorCode() + " (" + jrtReq.errorMessage() + "), scheduling new connect " +
+                " in " + delay + " ms";
+        log.log(logLevel, logMessage);
+        scheduleNextRequest(jrtReq, sub, delay, calculateErrorTimeout());
+    }
+
+    private void handleOKRequest(JRTClientConfigRequest jrtReq,
+                                 JRTConfigSubscription<ConfigInstance> sub,
+                                 Connection connection) {
+        // Reset counters pertaining to error handling here
+        fatalFailures = 0;
+        transientFailures = 0;
+        suspendWarned = 0;
+        connection.setSuccess();
+        sub.setLastCallBackOKTS(System.currentTimeMillis());
+        if (jrtReq.hasUpdatedGeneration()) {
+            // We only want this latest generation to be in the queue, we do not preserve history in this system
+            handleEmptyPayload(jrtReq, sub);
+            sub.getReqQueue().clear();
+            boolean putOK = sub.getReqQueue().offer(jrtReq);
+            if (!putOK) {
+                sub.setException(new ConfigurationRuntimeException("Could not put returned request on queue of subscription " + sub));
+            }
+        }
+        if (sub.getState() != ConfigSubscription.State.OPEN) return;
+        scheduleNextRequest(jrtReq, sub,
+                calculateSuccessDelay(),
+                calculateSuccessTimeout());
+    }
+
+    private long calculateSuccessTimeout() {
+        return timingValues.getPlusMinusFractionRandom(timingValues.getSuccessTimeout(), randomFraction);
+    }
+
+    private long calculateSuccessDelay() {
+        return timingValues.getPlusMinusFractionRandom(timingValues.getFixedDelay(), randomFraction);
+    }
+
+    /**
+     * This works around an optimization in the protocol: the payload is not set if it is not changed (seen from the server).
+     * So, if the sub's queue has a still _unprocessed_ req with payload, and the current one has no payload,
+     * i.e. it wasn't changed, save the one in the earlier req before clearing the queue.
+     *
+     * @param jrtReq a JRT config request
+     * @param sub    a config subscription
+     */
+    private void handleEmptyPayload(JRTClientConfigRequest jrtReq,
+                                    JRTConfigSubscription<ConfigInstance> sub) {
+        if (jrtReq.containsPayload()) {
+            JRTClientConfigRequest reqInQueue = sub.getReqQueue().poll(); // Just take it out, we were about to clear the queue anyway
+            if (reqInQueue != null) {
+                jrtReq.updateRequestPayload(reqInQueue.getNewPayload(), reqInQueue.hasUpdatedConfig());
+            }
+        }
+    }
+
+    private void scheduleNextRequest(JRTClientConfigRequest jrtReq, JRTConfigSubscription<?> sub, long delay, long timeout) {
+        if (delay < 0) delay = 0;
+        JRTClientConfigRequest jrtReqNew = jrtReq.nextRequest(timeout);
+        if (log.isLoggable(LogLevel.DEBUG)) {
+            log.log(LogLevel.DEBUG, "My timing values: " + timingValues);
+            log.log(LogLevel.DEBUG, "Scheduling new request " + delay + " millis from now for " + jrtReqNew.getConfigKey());
+        }
+        scheduler.schedule(new GetConfigTask(jrtReqNew, sub), delay, TimeUnit.MILLISECONDS);
+    }
+
+    /**
+     * Task that can be scheduled in a timer for executing a getConfig request
+     */
+    private class GetConfigTask implements Runnable {
+        private final JRTClientConfigRequest jrtReq;
+        private final JRTConfigSubscription<?> sub;
+
+        public GetConfigTask(JRTClientConfigRequest jrtReq,
+                             JRTConfigSubscription<?> sub) {
+            this.jrtReq = jrtReq;
+            this.sub = sub;
+        }
+
+        public void run() {
+            doRequest(sub, jrtReq, jrtReq.getTimeout());
+        }
+    }
+
+    public void close() {
+        suspendWarned = System.currentTimeMillis(); // Avoid printing warnings after this
+        connectionPool.close();
+        scheduler.shutdown();
+    }
+
+    private class JRTSourceThreadFactory implements ThreadFactory {
+        @SuppressWarnings("NullableProblems")
+        @Override
+        public Thread newThread(Runnable runnable) {
+            ThreadFactory tf = Executors.defaultThreadFactory();
+            Thread t = tf.newThread(runnable);
+            // We want a daemon thread to avoid hanging threads in case something goes wrong in the config system
+            t.setDaemon(true);
+            return t;
+        }
+    }
+
+    @SuppressWarnings("rawtypes")
+    private static class RequestContext {
+        final JRTConfigSubscription sub;
+        final JRTClientConfigRequest jrtReq;
+        final Connection connection;
+
+        private RequestContext(JRTConfigSubscription sub, JRTClientConfigRequest jrtReq, Connection connection) {
+            this.sub = sub;
+            this.jrtReq = jrtReq;
+            this.connection = connection;
+        }
+    }
+
+    int getTransientFailures() {
+        return transientFailures;
+    }
+
+    int getFatalFailures() {
+        return fatalFailures;
+    }
+
+    // TODO: Should be package private
+    public ConnectionPool getConnectionPool() {
+        return connectionPool;
+    }
+
+    private Double getClientTimeout(long serverTimeout) {
+        return (serverTimeout / 1000.0) + additionalTimeForClientTimeout;
+    }
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/impl/JRTConfigSubscription.java b/config/src/main/java/com/yahoo/config/subscription/impl/JRTConfigSubscription.java
new file mode 100644
index 00000000000..4405ca2f05c
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/impl/JRTConfigSubscription.java
@@ -0,0 +1,190 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription.impl;
+
+import java.util.concurrent.LinkedBlockingQueue;
+import java.util.concurrent.TimeUnit;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.subscription.ConfigInterruptedException;
+import com.yahoo.config.subscription.ConfigSource;
+import com.yahoo.config.subscription.ConfigSourceSet;
+import com.yahoo.config.subscription.ConfigSubscriber;
+import com.yahoo.log.LogLevel;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.ConfigPayload;
+import com.yahoo.vespa.config.JRTConnectionPool;
+import com.yahoo.vespa.config.TimingValues;
+import com.yahoo.vespa.config.protocol.CompressionType;
+import com.yahoo.vespa.config.protocol.JRTClientConfigRequest;
+import com.yahoo.vespa.config.protocol.Payload;
+
+/**
+ * A JRT config subscription uses one {@link JRTConfigRequester} to fetch config using Vespa RPC from a config source, typically proxy or server
+ *
+ * @author vegardh
+ * @since 5.1
+ */
+public class JRTConfigSubscription<T extends ConfigInstance> extends ConfigSubscription<T> {
+    private JRTConfigRequester requester;
+    private TimingValues timingValues;
+    // Last time we got an OK JRT callback for this
+    private long lastOK=0;
+
+    /**
+     * The queue containing either nothing or the one (newest) request that has got callback from JRT,
+     * but has not yet been handled.
+     */
+    private LinkedBlockingQueue<JRTClientConfigRequest> reqQueue = new LinkedBlockingQueue<>();
+    private ConfigSourceSet sources;
+
+    public JRTConfigSubscription(ConfigKey<T> key, ConfigSubscriber subscriber, ConfigSource source, TimingValues timingValues) {
+        super(key, subscriber);
+        this.timingValues=timingValues;
+        if (source instanceof ConfigSourceSet) {
+            this.sources=(ConfigSourceSet) source;
+        }
+    }
+
+    @Override
+    public boolean nextConfig(long timeoutMillis) {
+        // These flags may have been left true from a previous call, since ConfigSubscriber's nextConfig
+        // not necessarily returned true and reset the flags then
+        boolean gotNew = isGenerationChanged() || isConfigChanged() || hasException();
+        // Return that now, if there's nothing in queue, so that ConfigSubscriber can move on to other subscriptions to check
+        if (getReqQueue().peek()==null && gotNew) {
+            return true;
+        }
+        // Otherwise poll the queue for another generation or timeout
+        //
+        // Note: since the JRT callback thread will clear the queue first when it inserts a brand new element,
+        // there is a race here. However: the caller will handle it no matter what it gets from the queue here,
+        // the important part is that local state on the subscription objects is preserved.
+        if (!pollQueue(timeoutMillis)) return gotNew;
+        gotNew = isGenerationChanged() || isConfigChanged() || hasException();
+        return gotNew;
+    }
+
+    /**
+     * Polls the callback queue and <em>maybe</em> sets the following (caller must check): generation, generation changed, config, config changed
+     * Important: it never <em>resets</em> those flags, we must persist that state until the {@link ConfigSubscriber} clears it
+     * @param timeoutMillis timeout when polling (returns after at most this time)
+     * @return true if it got anything off the queue and <em>maybe</em> changed any state, false if timed out taking from queue
+     */
+    private boolean pollQueue(long timeoutMillis) {
+        JRTClientConfigRequest jrtReq;
+        try {
+            // Only valid responses are on queue, no need to validate
+            jrtReq = getReqQueue().poll(timeoutMillis, TimeUnit.MILLISECONDS);
+        } catch (InterruptedException e1) {
+            throw new ConfigInterruptedException(e1);
+        }
+        if (jrtReq == null) {
+            // timed out, we know nothing new.
+            return false;
+        }
+        if (jrtReq.hasUpdatedGeneration()) {
+            //printStatus(jrtReq, "Updated generation or config");
+            setGeneration(jrtReq.getNewGeneration());
+            setGenerationChanged(true);
+            if (jrtReq.hasUpdatedConfig()) {
+                // payload changed
+                setNewConfig(jrtReq);
+                setConfigChanged(true);
+            }
+        }
+        return true;
+    }
+
+    protected void setNewConfig(JRTClientConfigRequest jrtReq) {
+        setConfig(toConfigInstance(jrtReq));
+    }
+
+    /**
+     * This method should ideally throw new MissingConfig/Configuration exceptions and let the caller
+     * catch them. However, this would make the code in JRT/File/RawSource uglier.
+     * Alternatively, it could return a SetConfigStatus object with an int and an error message.
+     *
+     * @param jrtRequest a config request
+     * @return an instance of a config class (subclass of ConfigInstance)
+     */
+    T toConfigInstance(JRTClientConfigRequest jrtRequest) {
+        Payload payload = jrtRequest.getNewPayload();
+        ConfigPayload configPayload = ConfigPayload.fromUtf8Array(payload.withCompression(CompressionType.UNCOMPRESSED).getData());
+        T configInstance = configPayload.toInstance(configClass, jrtRequest.getConfigKey().getConfigId());
+        configInstance.setConfigMd5(jrtRequest.getNewConfigMd5());
+        return configInstance;
+    }
+
+    LinkedBlockingQueue<JRTClientConfigRequest> getReqQueue() {
+        return reqQueue;
+    }
+
+    @Override
+    public boolean subscribe(long timeout) {
+        lastOK=System.currentTimeMillis();
+        requester = getRequester();
+        requester.request(this);
+        JRTClientConfigRequest req = reqQueue.peek();
+        while (req == null && (System.currentTimeMillis() - lastOK <= timeout)) {
+            try {
+                Thread.sleep(10);
+            } catch (InterruptedException e) {
+                throw new ConfigInterruptedException(e);
+            }
+            req = reqQueue.peek();
+        }
+        return req != null;
+    }
+
+    private JRTConfigRequester getRequester() {
+        JRTConfigRequester requester = subscriber.requesters().get(sources);
+        if (requester==null) {
+            requester = new JRTConfigRequester(new JRTConnectionPool(sources), timingValues);
+            subscriber.requesters().put(sources, requester);
+        }
+        return requester;
+    }
+
+    @Override
+    @SuppressWarnings("serial")
+    public void close() {
+        super.close();
+        reqQueue = new LinkedBlockingQueue<JRTClientConfigRequest>() {
+            @Override public void put(JRTClientConfigRequest e) throws InterruptedException {
+                // When closed, throw away all requests that callbacks try to put
+            }
+        };
+    }
+
+    /**
+     * The timing values of this
+     * @return timing values
+     */
+    public TimingValues timingValues() {
+        return timingValues;
+    }
+
+    // Used in integration tests
+    @SuppressWarnings("UnusedDeclaration")
+    public JRTConfigRequester requester() {
+        return requester;
+    }
+
+    @Override
+    public void reload(long generation) {
+        log.log(LogLevel.DEBUG, "reload() is without effect on a JRTConfigSubscription.");
+    }
+
+    void setLastCallBackOKTS(long lastCallBackOKTS) {
+        this.lastOK = lastCallBackOKTS;
+    }
+
+    // For debugging
+    @SuppressWarnings("UnusedDeclaration")
+    static void printStatus(JRTClientConfigRequest request, String message) {
+        final String name = request.getConfigKey().getName();
+        if (name.equals("components") || name.equals("chains")) {
+            log.log(LogLevel.INFO, message + ":" + name + ":" + ", request=" + request);
+        }
+    }
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/impl/JarConfigSubscription.java b/config/src/main/java/com/yahoo/config/subscription/impl/JarConfigSubscription.java
new file mode 100644
index 00000000000..434b61db918
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/impl/JarConfigSubscription.java
@@ -0,0 +1,104 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription.impl;
+
+import java.io.IOException;
+import java.io.InputStreamReader;
+import java.io.UnsupportedEncodingException;
+import java.util.Arrays;
+import java.util.jar.JarFile;
+import java.util.zip.ZipEntry;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.ConfigurationRuntimeException;
+import com.yahoo.config.subscription.CfgConfigPayloadBuilder;
+import com.yahoo.config.subscription.ConfigInterruptedException;
+import com.yahoo.config.subscription.ConfigSubscriber;
+import com.yahoo.io.IOUtils;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.ConfigPayload;
+
+/**
+ * Subscription to use when config id is jar:.../foo.jar[!/pathInJar/]
+ *
+ * @author vegardh
+ * @author gjoranv
+ * @since 5.1
+ *
+ */
+public class JarConfigSubscription<T extends ConfigInstance> extends ConfigSubscription<T> {
+    private final String jarName;
+    private final String path;
+    private ZipEntry zipEntry = null;
+
+    // jar:configs/app.jar!/configs/
+    JarConfigSubscription(ConfigKey<T> key, ConfigSubscriber subscriber, String jarName, String path) {
+        super(key, subscriber);
+        this.jarName=jarName;
+        this.path=path;
+    }
+
+    @Override
+    public boolean nextConfig(long timeout) {
+        if (checkReloaded()) {
+            // Not supporting changing the payload for jar
+            return true;
+        }
+        if (zipEntry==null) {
+            // First time polled
+            JarFile jarFile = null;
+            try {
+                jarFile = new JarFile(jarName);
+            } catch (IOException e) {
+                throw new IllegalArgumentException(e);
+            }
+            zipEntry = getEntry(jarFile, path);
+            if (zipEntry==null) throw new IllegalArgumentException("Config '" + key.getName() + "' not found in '" + jarName + "!/" + path + "'.");
+            try {
+                ConfigPayload payload = new CfgConfigPayloadBuilder().deserialize(Arrays.asList(IOUtils.readAll(new InputStreamReader(jarFile.getInputStream(zipEntry), "UTF-8")).split("\n")));
+                config = payload.toInstance(configClass, key.getConfigId());
+            } catch (UnsupportedEncodingException e) {
+                throw new IllegalStateException(e);
+            } catch (IOException e) {
+                throw new ConfigurationRuntimeException(e);
+            }
+            setGeneration(0l);
+            setGenerationChanged(true);
+            setConfigChanged(true);
+            try {
+                jarFile.close();
+            } catch (IOException e) {
+                // TODO Auto-generated catch block
+                e.printStackTrace();
+            }
+            return true;
+        }
+        // TODO: Should wait and detect changes
+        try {
+            Thread.sleep(timeout);
+        } catch (InterruptedException e) {
+            throw new ConfigInterruptedException(e);
+        }
+        // These shouldn't be checked anywhere since we return false now, but setting them still
+        setGenerationChanged(false);
+        setConfigChanged(false);
+        return false;
+    }
+    /**
+     * Returns the entry corresponding to the ConfigInstance's defName/Version in the given directory in
+     * the given JarFile.
+     * If the file with correct version number does not exist, returns the filename without version number.
+     * The file's existence is checked elsewhere.
+     */
+    private ZipEntry getEntry(JarFile jarFile, String dir) {
+        if (!dir.endsWith("/")) {
+            dir = dir + '/';
+        }
+        return jarFile.getEntry(dir + getConfigFilenameNoVersion(key));
+    }
+
+    @Override
+    public boolean subscribe(long timeout) {
+        return true;
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/impl/MockConnection.java b/config/src/main/java/com/yahoo/config/subscription/impl/MockConnection.java
new file mode 100644
index 00000000000..3e9047b3bfa
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/impl/MockConnection.java
@@ -0,0 +1,159 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription.impl;
+
+import com.yahoo.jrt.Request;
+import com.yahoo.jrt.RequestWaiter;
+import com.yahoo.vespa.config.ConfigPayload;
+import com.yahoo.vespa.config.Connection;
+import com.yahoo.vespa.config.ConnectionPool;
+import com.yahoo.vespa.config.protocol.JRTServerConfigRequestV3;
+import com.yahoo.vespa.config.protocol.Payload;
+import com.yahoo.vespa.config.util.ConfigUtils;
+
+/**
+ * For unit testing
+ *
+ * @author <a href="mailto:musum@yahoo-inc.com">Harald Musum</a>
+ * @since 5.1.11
+ */
+public class MockConnection implements ConnectionPool, com.yahoo.vespa.config.Connection {
+
+    private Request lastRequest;
+    private final ResponseHandler responseHandler;
+    private int numberOfRequests = 0;
+
+    public int getNumberOfFailovers() {
+        return numberOfFailovers;
+    }
+
+    private int numberOfFailovers = 0;
+    private final int numSpecs;
+
+    public MockConnection() {
+        this(new OKResponseHandler());
+    }
+
+    public MockConnection(ResponseHandler responseHandler) {
+        this(responseHandler, 1);
+    }
+
+    public MockConnection(ResponseHandler responseHandler, int numSpecs) {
+        this.responseHandler = responseHandler;
+        this.numSpecs = numSpecs;
+    }
+
+    @Override
+    public void invokeAsync(Request request, double jrtTimeout, RequestWaiter requestWaiter) {
+        numberOfRequests++;
+        lastRequest = request;
+        responseHandler.requestWaiter(requestWaiter).request(request);
+        Thread t = new Thread(responseHandler);
+        t.setDaemon(true);
+        t.run();
+    }
+
+    @Override
+    public void setError(int errorCode) {
+        numberOfFailovers++;
+    }
+
+    @Override
+    public void setSuccess() {
+        numberOfFailovers = 0;
+    }
+
+    @Override
+    public String getAddress() {
+        return null;
+    }
+
+    @Override
+    public void close() {
+
+    }
+
+    @Override
+    public void setError(Connection connection, int errorCode) {
+        connection.setError(errorCode);
+    }
+
+    @Override
+    public Connection getCurrent() {
+        return this;
+    }
+
+    @Override
+    public Connection setNewCurrentConnection() {
+        return this;
+    }
+
+    @Override
+    public int getSize() {
+        return numSpecs;
+    }
+
+    public int getNumberOfRequests() {
+        return numberOfRequests;
+    }
+
+    public Request getRequest() {
+        return lastRequest;
+    }
+
+    static class OKResponseHandler extends AbstractResponseHandler {
+        protected void createResponse() {
+            JRTServerConfigRequestV3 jrtReq = JRTServerConfigRequestV3.createFromRequest(request);
+            Payload payload = Payload.from(ConfigPayload.empty());
+            long generation = 1;
+            jrtReq.addOkResponse(payload, generation, ConfigUtils.getMd5(payload.getData()));
+        }
+    }
+
+
+    public interface ResponseHandler extends Runnable {
+
+        RequestWaiter requestWaiter();
+
+        Request request();
+
+        ResponseHandler requestWaiter(RequestWaiter requestWaiter);
+
+        ResponseHandler request(Request request);
+    }
+
+    public abstract static class AbstractResponseHandler implements ResponseHandler {
+        private RequestWaiter requestWaiter;
+        protected Request request;
+
+        @Override
+        public RequestWaiter requestWaiter() {
+            return requestWaiter;
+        }
+
+        @Override
+        public Request request() {
+            return request;
+        }
+
+        @Override
+        public ResponseHandler requestWaiter(RequestWaiter requestWaiter) {
+            this.requestWaiter = requestWaiter;
+            return this;
+        }
+
+        @Override
+        public ResponseHandler request(Request request) {
+            this.request = request;
+            return this;
+        }
+
+        @Override
+        public void run() {
+            createResponse();
+            requestWaiter.handleRequestDone(request);
+        }
+
+        protected abstract void createResponse();
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/impl/RawConfigSubscription.java b/config/src/main/java/com/yahoo/config/subscription/impl/RawConfigSubscription.java
new file mode 100644
index 00000000000..2c8470cf63c
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/impl/RawConfigSubscription.java
@@ -0,0 +1,62 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription.impl;
+
+import java.util.Arrays;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.subscription.CfgConfigPayloadBuilder;
+import com.yahoo.config.subscription.ConfigInterruptedException;
+import com.yahoo.config.subscription.ConfigSubscriber;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.ConfigPayload;
+
+/**
+ * Subscription used when config id is raw:...
+ *
+ * Config is the actual text given after the config id, with newlines
+ *
+ * @author vegardh
+ * @since 5.1
+ *
+ */
+public class RawConfigSubscription<T extends ConfigInstance> extends ConfigSubscription<T> {
+    final String inputPayload;
+    String payload;
+
+    RawConfigSubscription(ConfigKey<T> key, ConfigSubscriber subscriber, String pl) {
+        super(key, subscriber);
+        this.inputPayload=pl;
+    }
+
+    @Override
+    public boolean nextConfig(long timeout) {
+        if (checkReloaded()) {
+            return true;
+        }
+        if (payload==null) {
+            payload = inputPayload;
+            setGeneration(0l);
+            setGenerationChanged(true);
+            setConfigChanged(true);
+
+            ConfigPayload configPayload = new CfgConfigPayloadBuilder().deserialize(Arrays.asList(payload.split("\n")));
+            config = configPayload.toInstance(configClass, key.getConfigId());
+            return true;
+        }
+        try {
+            Thread.sleep(timeout);
+        } catch (InterruptedException e) {
+            throw new ConfigInterruptedException(e);
+        }
+        // These shouldn't be checked anywhere since we return false now, but setting them still
+        setGenerationChanged(false);
+        setConfigChanged(false);
+        return false;
+    }
+
+    @Override
+    public boolean subscribe(long timeout) {
+        return true;
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/config/subscription/package-info.java b/config/src/main/java/com/yahoo/config/subscription/package-info.java
new file mode 100644
index 00000000000..7a77088a43e
--- /dev/null
+++ b/config/src/main/java/com/yahoo/config/subscription/package-info.java
@@ -0,0 +1,10 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+@ExportPackage
+@PublicApi
+/**
+ * Classes for subscribing to Vespa config.
+ */
+package com.yahoo.config.subscription;
+
+import com.yahoo.api.annotations.PublicApi;
+import com.yahoo.osgi.annotation.ExportPackage;
diff --git a/config/src/main/java/com/yahoo/jrt/.gitignore b/config/src/main/java/com/yahoo/jrt/.gitignore
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/main/java/com/yahoo/jrt/.gitignore
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigCacheKey.java b/config/src/main/java/com/yahoo/vespa/config/ConfigCacheKey.java
new file mode 100644
index 00000000000..15e67138393
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ConfigCacheKey.java
@@ -0,0 +1,62 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+/**
+ * A ConfigKey that also uses the def MD5 sum. Used for caching when def payload is user provided.
+ * @author vegardh
+ *
+ */
+public class ConfigCacheKey {
+    private final ConfigKey<?> key;
+    private final String defMd5;
+
+    /**
+     * Constructs a new server key based on the contents of the given {@link ConfigKey} and the def md5 sum.
+     * @param key The key to base on
+     * @param defMd5 MD5 checksum of the config definition. Never null.
+     */
+    public ConfigCacheKey(ConfigKey<?> key, String defMd5) {
+        this.key = key;
+        this.defMd5 = defMd5 == null ? "" : defMd5;
+    }
+
+    /**
+     * Constructs new key
+     *
+     * @param name           config definition name
+     * @param configIdString Can be null.
+     * @param namespace      namespace for this config definition
+     * @param defMd5         MD5 checksum of the config definition. Never null.
+     */
+    ConfigCacheKey(String name, String configIdString, String namespace, String defMd5) {
+        this(new ConfigKey<>(name, configIdString, namespace), defMd5);
+    }
+
+    @Override
+    public int hashCode() {
+        return key.hashCode() + 37 * defMd5.hashCode();
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        return o instanceof ConfigCacheKey && key.equals(((ConfigCacheKey) o).getKey())
+                && defMd5.equals(((ConfigCacheKey)o).defMd5);
+    }
+
+    /**
+     * The def md5 sum of this key
+     * @return md5 sum
+     */
+    public String getDefMd5() {
+        return defMd5;
+    }
+
+    public ConfigKey<?> getKey() {
+        return key;
+    }
+
+    @Override
+    public String toString() {
+        return key + "," + defMd5;
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigDefinition.java b/config/src/main/java/com/yahoo/vespa/config/ConfigDefinition.java
new file mode 100644
index 00000000000..9b4f8d12756
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ConfigDefinition.java
@@ -0,0 +1,1068 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.codegen.CNode;
+import com.yahoo.yolean.Exceptions;
+
+import java.util.*;
+import java.util.logging.Logger;
+import java.util.regex.Pattern;
+
+/**
+ * Represents one legal def file, or (internally) one array or inner array definition in a def file.
+ * Definitions are comparable based on version.
+ * @author vegardh
+ *
+ */
+public class ConfigDefinition implements Comparable<ConfigDefinition> {
+    public static final Pattern namePattern = Pattern.compile("[a-zA-Z][a-zA-Z0-9-_]*");
+    public static final Pattern namespacePattern = Pattern.compile("[a-zA-Z][a-zA-Z0-9-\\._]*");
+
+    public static Logger log = Logger.getLogger(ConfigDefinition.class.getName());
+    private final String name;
+    private final String version;
+    private final String namespace;
+    protected ConfigDefinition parent = null;
+
+    // TODO Strings without default are null, could be not OK.
+    private Map<String, StringDef> stringDefs = new LinkedHashMap<String, StringDef>();
+    private Map<String, BoolDef> boolDefs = new LinkedHashMap<String, BoolDef>();
+    private Map<String, IntDef> intDefs = new LinkedHashMap<String, IntDef>();
+    private Map<String, LongDef> longDefs = new LinkedHashMap<String, LongDef>();
+    private Map<String, DoubleDef> doubleDefs = new LinkedHashMap<String, DoubleDef>();
+    private Map<String, EnumDef> enumDefs = new LinkedHashMap<String, EnumDef>();
+    private Map<String, RefDef> referenceDefs = new LinkedHashMap<String, RefDef>();
+    private Map<String, FileDef> fileDefs = new LinkedHashMap<String, FileDef>();
+    private Map<String, PathDef> pathDefs = new LinkedHashMap<>();
+    private Map<String, StructDef> structDefs = new LinkedHashMap<String, StructDef>();
+    private Map<String, InnerArrayDef> innerArrayDefs = new LinkedHashMap<String, InnerArrayDef>();
+    private Map<String, ArrayDef> arrayDefs = new LinkedHashMap<String, ArrayDef>();
+    private Map<String, LeafMapDef> leafMapDefs = new LinkedHashMap<>();
+    private Map<String, StructMapDef> structMapDefs = new LinkedHashMap<>();
+
+    public static final Integer INT_MIN = -0x80000000;
+    public static final Integer INT_MAX = 0x7fffffff;
+
+    public static final Long LONG_MIN = -0x8000000000000000L;
+    public static final Long LONG_MAX = 0x7fffffffffffffffL;
+
+    public static final Double DOUBLE_MIN = -1e308d;
+    public static final Double DOUBLE_MAX = 1e308d;
+
+    public ConfigDefinition(String name, String version, String namespace) {
+        this.name = name;
+        this.version = version;
+        this.namespace = namespace;
+    }
+
+    public ConfigDefinition(String name, String version) {
+        this(name, version, CNode.DEFAULT_NAMESPACE);
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public String getVersion() {
+        return version;
+    }
+
+    public String getNamespace() {
+        return namespace;
+    }
+
+    /** @return  The parent ConfigDefinition, or null if this is the root. */
+    public ConfigDefinition getParent() {
+        return parent;
+    }
+
+    /** @return The root ConfigDefinition, might be this. */
+    public ConfigDefinition getRoot() {
+        ConfigDefinition ancestor = this;
+        while (ancestor.getParent() != null) {
+            ancestor = ancestor.getParent();
+        }
+        return ancestor;
+    }
+
+    private static void defFail(String id, String val, String type, Exception e, List<String> warnings) {
+        defFail("Invalid value '" + val + "' for " + type + " '" + id + "'. "+ Exceptions.toMessageString(e), warnings);
+    }
+
+    public void verify(String id, String val, List<String> warnings) {
+        if (stringDefs.containsKey(id)) {
+            verifyString(id, warnings);
+        } else if (enumDefs.containsKey(id)) {
+            verifyEnum(id ,val, warnings);
+        } else if (referenceDefs.containsKey(id)) {
+            verifyReference(id, warnings);
+        } else if (fileDefs.containsKey(id)) {
+            verifyFile(id, warnings);
+        } else if (pathDefs.containsKey(id)) {
+            verifyPath(id, warnings);
+        } else if (boolDefs.containsKey(id)) {
+            verifyBool(id, val, warnings);
+        } else if (intDefs.containsKey(id)) {
+            verifyInt(id, val, warnings);
+        } else if (longDefs.containsKey(id)) {
+            verifyLong(id, val, warnings);
+        } else if (doubleDefs.containsKey(id)) {
+            verifyDouble(id, val, warnings);
+        } else if (structDefs.containsKey(id)) {
+            verifyStruct(id, warnings);
+        } else if (arrayDefs.containsKey(id)) {
+            verifyArray(id, warnings);
+        } else if (innerArrayDefs.containsKey(id)) {
+            verifyInnerArray(id, warnings);
+        } else if (leafMapDefs.containsKey(id)) {
+		verifyLeafMap(id, warnings);
+        } else if (structMapDefs.containsKey(id)) {
+            verifyStructMap(id, warnings);
+        } else {
+            defFail("No such field in definition " + getRoot().getNamespace() + "." + getRoot().getName() +
+                    ": " + getAncestorString() + id, warnings);
+        }
+    }
+
+    private boolean verifyDouble(String id, String val, List<String> warnings) {
+        try {
+            return verifyDouble(id, Double.parseDouble(val), warnings);
+        } catch (NumberFormatException e) {
+            defFail(id, val, "double", e, warnings);
+            return false;
+        }
+    }
+
+    private boolean verifyBool(String id, String val, List<String> warnings) {
+        if ("true".equalsIgnoreCase(val) || "false".equalsIgnoreCase(val)) {
+            return verifyBool(id, warnings);
+        } else {
+            defFail(id, val, "bool", null, warnings);
+            return false;
+        }
+    }
+
+    public void verify(String id, List<String> warnings) {
+        verify(id, null, warnings);
+    }
+
+    /**
+     * Compares def-versions. Examples: 2 is higher than 1, and 2-0-0 is higher than 1-2-2 but the same as 2.
+     */
+    public static class VersionComparator implements Comparator<String> {
+        int[] parseVersion(String version) {
+            int[] result = {0, 0, 0};
+            String[] v = version.split("-");
+
+            for (int i = 0; i < 3; i++) {
+                if (v.length > i) result[i] = Integer.parseInt(v[i]);
+            }
+
+            return result;
+        }
+
+        public int compare(String o1, String o2) throws ClassCastException {
+            int[] version1 = parseVersion(o1);
+            int[] version2 = parseVersion(o2);
+
+            for (int i = 0; i < 3; i ++) {
+                int diff = version1[i] - version2[i];
+                if (diff != 0) return diff;
+            }
+
+            return 0;
+        }
+    }
+
+    /**
+     * String based ("untyped") type specification used by parser and arrays. May have the name of the field which it describes.
+     * The index number is used to export data in correct order.
+     * @author vegardh
+     *
+     */
+    public static class TypeSpec {
+        private String type; // TODO Class?
+        private Integer index;
+        private String name;
+        private Object defVal;
+        private Object min;
+        private Object max;
+        private List<String> enumVals;
+
+        public TypeSpec(String name, String type, Object defVal, String enumValsCommaSep, Object min, Object max) {
+            this.name=name;
+            this.type = type;
+            this.defVal = defVal;
+            this.enumVals = getEnumVals(enumValsCommaSep);
+            this.min = min;
+            this.max = max;
+        }
+
+        private List<String> getEnumVals(String commaSep) {
+            if (commaSep==null) {
+                return null;
+            }
+            List<String> in = new ArrayList<String>();
+            for (String val: commaSep.split(",")) {
+                in.add(val.trim());
+            }
+            return in;
+        }
+        public String getName() {
+            return name;
+        }
+        public String getType() {
+            return type;
+        }
+        /*public Class getTypeClass() {
+          return typeClass;
+          }*/
+        public Object getDef() {
+            return defVal;
+        }
+        public Object getMin() {
+            return min;
+        }
+        public Object getMax() {
+            return max;
+        }
+        public List<String> getEnumVals() {
+            return enumVals;
+        }
+
+        public boolean checkValue(String id, String val, int index, List<String> warnings) {
+            if ("int".equals(getType())) {
+                return checkInt(id, val, index, warnings);
+            } else if ("long".equals(getType())) {
+                return checkLong(id, val, index, warnings);
+            } else if ("double".equals(getType())) {
+                return checkDouble(id, val, index, warnings);
+            } else if ("enum".equals(getType())) {
+                return checkEnum(id, val, index, warnings);
+            }
+            return true;
+        }
+
+        private boolean checkEnum(String id, String val, int index, List<String> warnings) {
+            if (!getEnumVals().contains(val)) {
+                ConfigDefinition.failInvalidEnum(val, id, id+"["+index+"]", warnings);
+                return false;
+            }
+            return true;
+        }
+
+        private boolean checkDouble(String id, String val, int index, List<String> warnings) {
+            try {
+                return checkDouble(Double.parseDouble(val), id, index, warnings);
+            } catch (NumberFormatException e) {
+                ConfigDefinition.defFail(id, val, "double", e, warnings);
+                return false;
+            }
+        }
+
+        private boolean checkLong(String id, String val, int index, List<String> warnings) {
+            try {
+                return checkLong(Long.parseLong(val), id, index, warnings);
+            } catch (NumberFormatException e) {
+                ConfigDefinition.defFail(id, val, "long", e, warnings);
+                return false;
+            }
+        }
+
+        private boolean checkInt(String id, String val, int index, List<String> warnings) {
+            try {
+                return checkInt(Integer.parseInt(val), id, index, warnings);
+            } catch (NumberFormatException e) {
+                ConfigDefinition.defFail(id, val, "int", e, warnings);
+                return false;
+            }
+        }
+
+        private boolean checkInt(Integer theVal, String id, int arrayIndex, List<String> warnings) {
+            if (!"int".equals(getType())) {
+                ConfigDefinition.defFail("Illegal value \""+theVal+"\" for array \""+id+"\"", warnings);
+                return false;
+            }
+            if (getMax()!=null && theVal>(Integer)getMax()) {
+                ConfigDefinition.failTooBig(theVal, getMax(), id, id+"["+arrayIndex+"]", warnings);
+                return false;
+            }
+            if (getMin()!=null && theVal<(Integer)getMin()) {
+                ConfigDefinition.failTooSmall(theVal, getMin(), id, id+"["+arrayIndex+"]", warnings);
+                return false;
+            }
+            return true;
+        }
+
+        private boolean checkLong(Long theVal, String id, int arrayIndex, List<String> warnings) {
+            if (!"long".equals(getType())) {
+                ConfigDefinition.defFail("Illegal value \""+theVal+"\" for array \""+id+"\"", warnings);
+                return false;
+            }
+            if (getMax()!=null && theVal>(Long)getMax()) {
+                ConfigDefinition.failTooBig(theVal, getMax(), id, id+"["+arrayIndex+"]", warnings);
+                return false;
+            }
+            if (getMin()!=null && theVal<(Long)getMin()) {
+                ConfigDefinition.failTooSmall(theVal, getMin(), id, id+"["+arrayIndex+"]", warnings);
+                return false;
+            }
+            return true;
+        }
+
+        private boolean checkDouble(Double theVal, String id, int arrayIndex, List<String> warnings) {
+            if (!"double".equals(getType())) {
+                ConfigDefinition.defFail("Illegal value \""+theVal+"\" for array \""+id+"\", array type is "+getType(), warnings);
+                return false;
+            }
+            if (getMax()!=null && (theVal>(Double)getMax())) {
+                ConfigDefinition.failTooBig(theVal, getMax(), id, id+"["+arrayIndex+"]", warnings);
+                return false;
+            }
+            if (getMin()!=null && theVal<(Double)getMin()) {
+                ConfigDefinition.failTooSmall(theVal, getMin(), id, id+"["+arrayIndex+"]", warnings);
+                return false;
+            }
+            return true;
+        }
+
+        public void setIndex(Integer index) {
+            this.index = index;
+        }
+        public Integer getIndex() {
+            return index;
+        }
+    }
+
+    /**
+     * A ConfigDefinition that represents a struct, e.g. a.foo, a.bar where 'a' is the struct. Can be thought
+     * of as an inner array with only one element.
+     */
+    public static class StructDef extends ConfigDefinition {
+        public StructDef(String name, String version, ConfigDefinition parent) {
+            super(name, version);
+            this.parent = parent;
+        }
+    }
+
+    /**
+     * An InnerArray def is a ConfigDefinition with n scalar types of defs, and maybe sub-InnerArrays
+     * @author vegardh
+     *
+     */
+    public static class InnerArrayDef extends ConfigDefinition {
+        public InnerArrayDef(String name, String version, ConfigDefinition parent) {
+            super(name, version);
+            this.parent = parent;
+        }
+    }
+
+    /**
+     * An array def is a ConfigDefinition with only one other type of scalar def.
+     * @author vegardh
+     *
+     */
+    public static class ArrayDef extends ConfigDefinition {
+        private TypeSpec typeSpec;
+        public ArrayDef(String name, String version, ConfigDefinition parent) {
+            super(name, version);
+            this.parent = parent;
+        }
+        public TypeSpec getTypeSpec() {
+            return typeSpec;
+        }
+        public void setTypeSpec(TypeSpec typeSpec) {
+            this.typeSpec = typeSpec;
+        }
+
+        public void verify(String val, int index, List<String> warnings) {
+            if (val != null && getTypeSpec() != null) {
+                TypeSpec spec = getTypeSpec();
+                spec.checkValue(getName(), val, index, warnings);
+            }
+        }
+    }
+
+    /**
+     * Def of a myMap{} int
+     * @author vegardh
+     *
+     */
+    public static class LeafMapDef extends ConfigDefinition {
+	private TypeSpec typeSpec;
+	public LeafMapDef(String name, String version, ConfigDefinition parent) {
+            super(name, version);
+            this.parent = parent;
+        }
+	public TypeSpec getTypeSpec() {
+            return typeSpec;
+        }
+        public void setTypeSpec(TypeSpec typeSpec) {
+            this.typeSpec = typeSpec;
+        }
+    }
+
+    /**
+     * Def of a myMap{}.myInt int
+     * @author vegardh
+     *
+     */
+    public static class StructMapDef extends ConfigDefinition {
+	public StructMapDef(String name, String version, ConfigDefinition parent) {
+            super(name, version);
+            this.parent = parent;
+        }
+    }
+
+    /**
+     * A Default specification where instances _may_ have a default value
+     * @author vegardh
+     */
+    public static interface DefaultValued<T> {
+        public T getDefVal();
+    }
+
+    public static class EnumDef implements DefaultValued<String>{
+        private List<String> vals;
+        private String defVal;
+        public EnumDef(List<String> vals, String defVal) {
+            if (defVal!=null && !vals.contains(defVal)) {
+                throw new IllegalArgumentException("Def val "+defVal+" is not in given vals "+vals);
+            }
+            this.vals = vals;
+            this.defVal = defVal;
+        }
+        public List<String> getVals() {
+            return vals;
+        }
+
+        @Override
+        public String getDefVal() {
+            return defVal;
+        }
+    }
+
+    public static class StringDef implements DefaultValued<String> {
+        private String defVal;
+
+        public StringDef(String def) {
+            this.defVal=def;
+        }
+
+        @Override
+        public String getDefVal() {
+            return defVal;
+        }
+    }
+
+    public static class BoolDef implements DefaultValued<Boolean> {
+       private Boolean defVal;
+
+       public BoolDef(Boolean def) {
+           this.defVal=def;
+       }
+
+       @Override
+        public Boolean getDefVal() {
+           return defVal;
+       }
+    }
+
+    /** The type is called 'double' in .def files, but it is a 64-bit IEE 754 double,
+     * which means it must be represented as a double in Java
+     */
+    public static class DoubleDef implements DefaultValued<Double> {
+        private Double defVal;
+        private Double min;
+        private Double max;
+        public DoubleDef(Double defVal, Double min, Double max) {
+            super();
+            this.defVal = defVal;
+            if (min == null) {
+                this.min = DOUBLE_MIN;
+            } else {
+                this.min = min;
+            }
+            if (max == null){
+                this.max = DOUBLE_MAX;
+            } else {
+                this.max = max;
+            }
+        }
+
+        @Override
+        public Double getDefVal() {
+            return defVal;
+        }
+        public Double getMin() {
+            return min;
+        }
+        public Double getMax() {
+            return max;
+        }
+    }
+
+    public static class IntDef implements DefaultValued<Integer>{
+        private Integer defVal;
+        private Integer min;
+        private Integer max;
+        public IntDef(Integer def, Integer min, Integer max) {
+            super();
+            this.defVal = def;
+            if (min == null) {
+                this.min = INT_MIN;
+            } else {
+                this.min = min;
+            }
+            if (max == null) {
+                this.max = INT_MAX;
+            } else {
+                this.max = max;
+            }
+        }
+
+        @Override
+        public Integer getDefVal() {
+            return defVal;
+        }
+        public Integer getMin() {
+            return min;
+        }
+        public Integer getMax() {
+            return max;
+        }
+    }
+
+    public static class LongDef implements DefaultValued<Long>{
+        private Long defVal;
+        private Long min;
+        private Long max;
+        public LongDef(Long def, Long min, Long max) {
+            super();
+            this.defVal = def;
+            if (min == null) {
+                this.min = LONG_MIN;
+            } else {
+                this.min = min;
+            }
+            if (max == null) {
+                this.max = LONG_MAX;
+            } else {
+                this.max = max;
+            }
+        }
+
+        @Override
+        public Long getDefVal() {
+            return defVal;
+        }
+        public Long getMin() {
+            return min;
+        }
+        public Long getMax() {
+            return max;
+        }
+    }
+
+    public static class RefDef implements DefaultValued<String>{
+        private String defVal;
+
+        public RefDef(String defVal) {
+            super();
+            this.defVal = defVal;
+        }
+
+        @Override
+        public String getDefVal() {
+            return defVal;
+        }
+    }
+
+    public static class FileDef implements DefaultValued<String>{
+        private String defVal;
+
+        public FileDef(String defVal) {
+            super();
+            this.defVal = defVal;
+        }
+
+        @Override
+        public String getDefVal() {
+            return defVal;
+        }
+    }
+
+    public static class PathDef implements DefaultValued<String>{
+        private String defVal;
+
+        public PathDef(String defVal) {
+            this.defVal = defVal;
+        }
+
+        @Override
+        public String getDefVal() {
+            return defVal;
+        }
+    }
+
+    public void addEnumDef(String id, EnumDef def) {
+        enumDefs.put(id, def);
+    }
+
+    public void addInnerArrayDef(String id) {
+        innerArrayDefs.put(id, new InnerArrayDef(id, version, this));
+    }
+
+    public void addLeafMapDef(String id) {
+	leafMapDefs.put(id, new LeafMapDef(id, version, this));
+    }
+
+    public void addEnumDef(String id, List<String> vals, String defVal) {
+        List<String> in = new ArrayList<String>();
+        for (String ins: vals) {
+            in.add(ins.trim());
+        }
+        enumDefs.put(id, new EnumDef(in, defVal));
+    }
+
+    public void addEnumDef(String id, String valsCommaSep, String defVal) {
+        String[] valArr = valsCommaSep.split(",");
+        addEnumDef(id, Arrays.asList(valArr), defVal);
+    }
+
+    public void addStringDef(String id, String defVal) {
+        stringDefs.put(id, new StringDef(defVal));
+    }
+
+    public void addStringDef(String id) {
+        stringDefs.put(id, new StringDef(null));
+    }
+
+    public void addIntDef(String id, Integer defVal, Integer min, Integer max) {
+        intDefs.put(id, new IntDef(defVal, min, max));
+    }
+
+    public void addIntDef(String id, Integer defVal) {
+        addIntDef(id, defVal, INT_MIN, INT_MAX);
+    }
+
+    public void addIntDef(String id) {
+        addIntDef(id, null);
+    }
+
+    public void addLongDef(String id, Long defVal, Long min, Long max) {
+        longDefs.put(id, new LongDef(defVal, min, max));
+    }
+
+    public void addLongDef(String id, Long defVal) {
+        addLongDef(id, defVal, LONG_MIN, LONG_MAX);
+    }
+
+    public void addLongDef(String id) {
+        addLongDef(id, null);
+    }
+
+    public void addBoolDef(String id) {
+        boolDefs.put(id, new BoolDef(null));
+    }
+
+    public void addBoolDef(String id, Boolean defVal) {
+        boolDefs.put(id, new BoolDef(defVal));
+    }
+
+    public void addDoubleDef(String id, Double defVal, Double min, Double max) {
+        doubleDefs.put(id, new DoubleDef(defVal, min, max));
+    }
+
+    public void addDoubleDef(String id, Double defVal) {
+        addDoubleDef(id, defVal, DOUBLE_MIN, DOUBLE_MAX);
+    }
+
+    public void addDoubleDef(String id) {
+        addDoubleDef(id, null);
+    }
+
+    public void addReferenceDef(String refId, String defVal) {
+        referenceDefs.put(refId, new RefDef(defVal));
+    }
+
+    public void addReferenceDef(String refId) {
+        referenceDefs.put(refId, new RefDef(null));
+    }
+
+    public void addFileDef(String refId, String defVal) {
+        fileDefs.put(refId, new FileDef(defVal));
+    }
+
+    public void addFileDef(String refId) {
+        fileDefs.put(refId, new FileDef(null));
+    }
+
+    public void addPathDef(String refId, String defVal) {
+        pathDefs.put(refId, new PathDef(defVal));
+    }
+
+    public void addPathDef(String refId) {
+        pathDefs.put(refId, new PathDef(null));
+    }
+
+    public Map<String, StringDef> getStringDefs() {
+        return stringDefs;
+    }
+
+    public Map<String, BoolDef> getBoolDefs() {
+        return boolDefs;
+    }
+
+    public Map<String, IntDef> getIntDefs() {
+        return intDefs;
+    }
+
+    public Map<String, LongDef> getLongDefs() {
+        return longDefs;
+    }
+
+    public Map<String, DoubleDef> getDoubleDefs() {
+        return doubleDefs;
+    }
+
+    public Map<String, RefDef> getReferenceDefs() {
+        return referenceDefs;
+    }
+
+    public Map<String, FileDef> getFileDefs() {
+        return fileDefs;
+    }
+
+    public Map<String, PathDef> getPathDefs() {
+        return pathDefs;
+    }
+
+    public Map<String, InnerArrayDef> getInnerArrayDefs() {
+        return innerArrayDefs;
+    }
+
+    public Map<String, LeafMapDef> getLeafMapDefs() {
+		return leafMapDefs;
+	}
+
+    public Map<String, StructMapDef> getStructMapDefs() {
+		return structMapDefs;
+	}
+
+    public InnerArrayDef innerArrayDef(String name) {
+        InnerArrayDef ret = innerArrayDefs.get(name);
+        if (ret!=null) {
+            return ret;
+        }
+        ret = new InnerArrayDef(name, version, this);
+        innerArrayDefs.put(name, ret);
+        return ret;
+    }
+
+    public Map<String, StructDef> getStructDefs() {
+        return structDefs;
+    }
+
+    public StructDef structDef(String name) {
+        StructDef ret = structDefs.get(name);
+        if (ret!=null) {
+            return ret;
+        }
+        ret = new StructDef(name, version, this);
+        structDefs.put(name, ret);
+        return ret;
+    }
+
+    public Map<String, EnumDef> getEnumDefs() {
+        return enumDefs;
+    }
+
+    public ArrayDef arrayDef(String name) {
+        ArrayDef ret = arrayDefs.get(name);
+        if (ret!=null) {
+            return ret;
+        }
+        ret = new ArrayDef(name, version, this);
+        arrayDefs.put(name, ret);
+        return ret;
+    }
+
+    public Map<String, ArrayDef> getArrayDefs() {
+        return arrayDefs;
+    }
+
+    public StructMapDef structMapDef(String name) {
+	StructMapDef ret = structMapDefs.get(name);
+	if (ret!=null) {
+		return ret;
+	}
+	ret = new StructMapDef(name, version, this);
+	structMapDefs.put(name, ret);
+	return ret;
+    }
+
+    public LeafMapDef leafMapDef(String name) {
+	LeafMapDef ret = leafMapDefs.get(name);
+	if (ret!=null) {
+		return ret;
+	}
+	ret = new LeafMapDef(name, version, this);
+	leafMapDefs.put(name, ret);
+	return ret;
+    }
+
+    /**
+     * Throws if the given value is not legal
+     */
+    private boolean verifyDouble(String id, Double val, List<String> warnings) {
+        DoubleDef def = doubleDefs.get(id);
+        if (def==null) {
+            defFail("No such double in " + verifyWarning(id), warnings);
+            return false;
+        }
+        if (val==null) {
+            return true;
+        }
+        if (def.getMin()!=null && val<def.getMin()) {
+            failTooSmall(val, def.getMin(), toString(), getAncestorString()+id, warnings);
+            return false;
+        }
+        if (def.getMax()!=null && val>def.getMax()) {
+            failTooBig(val, def.getMax(), toString(), getAncestorString()+id, warnings);
+            return false;
+        }
+        return true;
+    }
+
+    /**
+     * Throws if the given value is not legal
+     */
+    private boolean verifyEnum(String id, String val, List<String> warnings) {
+        EnumDef def = enumDefs.get(id);
+        if (def==null) {
+            defFail("No such enum in " + verifyWarning(id), warnings);
+            return false;
+        }
+        if (!def.getVals().contains(val)) {
+            defFail("Invalid enum value '"+val+"' in def "+toString()+
+                    " enum '"+getAncestorString()+id+"'.", warnings);
+            return false;
+        }
+        return true;
+    }
+
+    /**
+     * Throws if the given value is not legal
+     */
+    private boolean verifyInt(String id, Integer val, List<String> warnings) {
+        IntDef def = intDefs.get(id);
+        if (def==null) {
+            defFail("No such integer in " + verifyWarning(id), warnings);
+            return false;
+        }
+        if (val==null) {
+            return true;
+        }
+        if (def.getMin()!=null && val<def.getMin()) {
+            failTooSmall(val, def.getMin(), name, id, warnings);
+            return false;
+        }
+        if (def.getMax()!=null && val>def.getMax()) {
+            failTooBig(val, def.getMax(), name, id, warnings);
+            return false;
+        }
+        return true;
+    }
+
+    private boolean verifyInt(String id, String val, List<String> warnings) {
+        try {
+            return verifyInt(id, Integer.parseInt(val), warnings);
+        } catch (NumberFormatException e) {
+            ConfigDefinition.defFail(id, val, "int", e, warnings);
+            return false;
+        }
+    }
+
+    private boolean verifyLong(String id, String val, List<String> warnings) {
+        try {
+            return verifyLong(id, Long.parseLong(val), warnings);
+        } catch (NumberFormatException e) {
+            ConfigDefinition.defFail(id, val, "long", e, warnings);
+            return false;
+        }
+    }
+
+    /**
+     * Throws if the given value is not legal
+     */
+    private boolean verifyLong(String id, Long val, List<String> warnings) {
+        LongDef def = longDefs.get(id);
+        if (def==null) {
+            defFail("No such long in " + verifyWarning(id), warnings);
+            return false;
+        }
+        if (val==null) {
+            return true;
+        }
+        if (def.getMin()!=null && val<def.getMin()) {
+            failTooSmall(val, def.getMin(), name, id, warnings);
+            return false;
+        }
+        if (def.getMax()!=null && val>def.getMax()) {
+            failTooBig(val, def.getMax(), name, id, warnings);
+            return false;
+        }
+        return true;
+    }
+
+    static void failTooSmall(Object val, Object min, String defName, String valKey, List<String> warnings) {
+        defFail("Value \""+valKey+"\" outside range in definition \""+defName+"\": "+val+"<"+min, warnings);
+    }
+
+    static void failTooBig(Object val, Object max, String defName, String valKey, List<String> warnings) {
+        defFail("Value \""+valKey+"\" outside range in definition \""+defName+"\": "+val+">"+max, warnings);
+    }
+
+    static void failInvalidEnum(Object val, String defName, String defKey, List<String> warnings) {
+        defFail("Invalid enum value \""+val+"\" for \""+defKey+"\" in definition \""+defName, warnings);
+    }
+
+    /**
+     * Adds the given log msg to list, and logs it
+     * @param msg failure message
+     * @param warnings list of warnings collected during model building.
+     * @return warnings list with msg added
+     */
+    static List<String> defFail(String msg, List<String> warnings) {
+        throw new IllegalArgumentException(msg);
+        // Idea here is to store errors in list instead, and throw from model builder in vespamodel instead. But not so important.
+        /*warnings.add(msg);
+        log.log(LogLevel.WARNING, msg);
+        return warnings;*/
+    }
+
+    private boolean verifyString(String id, List<String> warnings) {
+        if (!stringDefs.containsKey(id)) {
+            defFail("No such string in " + verifyWarning(id), warnings);
+            return false;
+        }
+        return true;
+    }
+
+    private boolean verifyReference(String id, List<String> warnings) {
+        if (!referenceDefs.containsKey(id)) {
+            defFail("No such reference in " + verifyWarning(id), warnings);
+            return false;
+        }
+        return true;
+    }
+
+    private boolean verifyFile(String id, List<String> warnings) {
+        if (!fileDefs.containsKey(id)) {
+            defFail("No such file in " + verifyWarning(id), warnings);
+            return false;
+        }
+        return true;
+    }
+
+    private boolean verifyPath(String id, List<String> warnings) {
+        if (!pathDefs.containsKey(id)) {
+            defFail("No such path in " + verifyWarning(id), warnings);
+            return false;
+        }
+        return true;
+    }
+
+    private boolean verifyBool(String id, List<String> warnings) {
+        if (!boolDefs.containsKey(id)) {
+            defFail("No such bool in " + verifyWarning(id), warnings);
+            return false;
+        }
+        return true;
+    }
+
+    private boolean verifyArray(String id, List<String> warnings) {
+        String failString = "No such array in " + verifyWarning(id);
+        if (!arrayDefs.containsKey(id)) {
+            if (innerArrayDefs.containsKey(id)) {
+                failString += ". However, the definition does contain an inner array with the same name.";
+            }
+            defFail(failString, warnings);
+            return false;
+        }
+        return true;
+    }
+
+    private boolean verifyInnerArray(String id, List<String> warnings) {
+        String failString = "No such inner array in " + verifyWarning(id);
+        if (!innerArrayDefs.containsKey(id)) {
+            if (arrayDefs.containsKey(id)) {
+                failString += ". However, the definition does contain an array with the same name.";
+            }
+            defFail(failString, warnings);
+            return false;
+        }
+        return true;
+    }
+
+    private boolean verifyStruct(String id, List<String> warnings) {
+        if (!structDefs.containsKey(id)) {
+            defFail("No such struct in " + verifyWarning(id), warnings);
+            return false;
+        }
+        return true;
+    }
+
+    private boolean verifyLeafMap(String id, List<String> warnings) {
+	if (!leafMapDefs.containsKey(id)) {
+		defFail("No such leaf map in " + verifyWarning(id), warnings);
+            return false;
+	}
+	return true;
+    }
+
+    private boolean verifyStructMap(String id, List<String> warnings) {
+	if (!structMapDefs.containsKey(id)) {
+		defFail("No such struct map in " + verifyWarning(id), warnings);
+            return false;
+	}
+	return true;
+    }
+
+    private String verifyWarning(String id) {
+        return "definition '" + getRoot().toString() + "': " + getAncestorString() + id;
+    }
+
+    /**
+     * Returns a string composed of the ancestors of this ConfigDefinition, skipping the root (which is the name
+     * of the .def file). For example, if this is an array called 'leafArray' and a child of 'innerArray' which
+     * is again a child of 'myStruct', then the returned string will be 'myStruct.innerArray.leafArray.'
+     * The trailing '.' is included for the caller's convenience.
+     *
+     * @return a string composed of the ancestors of this ConfigDefinition, not including the root.
+     */
+    public String getAncestorString() {
+        StringBuilder ret = new StringBuilder();
+        ConfigDefinition ancestor = this;
+        while (ancestor.getParent() != null) {
+            ret.insert(0, ancestor.getName() + ".");
+            ancestor = ancestor.getParent();
+        }
+        return ret.toString();
+    }
+
+    @Override
+    public int compareTo(ConfigDefinition other) {
+        Objects.requireNonNull(other);
+        if (!getName().equals(other.getName())) {
+            throw new IllegalArgumentException("Different def names used to compare: "+getName()+"/"+other.getName());
+        }
+        return new VersionComparator().compare(getVersion(),other.getVersion());
+    }
+
+    @Override
+    public String toString() {
+        return getNamespace() + "." + getName();
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigDefinitionBuilder.java b/config/src/main/java/com/yahoo/vespa/config/ConfigDefinitionBuilder.java
new file mode 100644
index 00000000000..6e9f2de5a0d
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ConfigDefinitionBuilder.java
@@ -0,0 +1,209 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.codegen.CNode;
+import com.yahoo.config.codegen.LeafCNode;
+
+import java.util.Arrays;
+
+/**
+ * Builds a ConfigDefinition from a tree of CNodes.
+ *
+ * @author <a href="musum@yahoo-inc.com">Harald Musum</a>
+ */
+public class ConfigDefinitionBuilder {
+
+    /**
+     * Creates a ConfigDefinition based on a tree generated from parsing a config
+     * definition file.
+     *
+     * @param root the root node in a tree generated from parsing a config definition file.
+     * @return a ConfigDefinition object
+     */
+    public static ConfigDefinition createConfigDefinition(CNode root) {
+        return createConfigDefinition(root, root.getNamespace());
+    }
+
+    // TODO This method should be removed when we have full namespace support
+    /**
+     * Creates a ConfigDefinition based on a tree generated from parsing a config
+     * definition file. The <code>namespace</code> argument overrides the namespace
+     * defined in the config definition file.
+     *
+     * @param root the root node in a tree generated from parsing a config definition file.
+     * @param namespace Override namespace in root with this namespace
+     * @return a ConfigDefinition object
+     */
+    public static ConfigDefinition createConfigDefinition(CNode root, String namespace) {
+        ConfigDefinition def = new ConfigDefinition(root.getName(), root.getVersion(), namespace);
+
+        for (CNode node : root.getChildren()) {
+            addNode(def, node);
+        }
+        return def;
+    }
+
+    /**
+     *
+     * @param def a ConfigDefinition object
+     * @param node the node to be added to the config definition
+     */
+    private static void addNode(ConfigDefinition def, CNode node) {
+        String name = node.getName();
+        if (node instanceof LeafCNode) {
+            if (node.isArray) {
+                //System.out.println("Adding array node " + name);
+                String enumValues = null;
+                String type = ((LeafCNode) node).getType();
+                if ("enum".equals(type)) {
+                    enumValues = convertToEnumValueCommaSeparated(((LeafCNode.EnumLeaf) node).getLegalValues());
+                }
+                def.arrayDef(name).setTypeSpec(
+                        new ConfigDefinition.TypeSpec(name, ((LeafCNode) node).getType(), null, enumValues, null, null));
+
+            } else if (node.isMap) {
+		//System.out.println("Adding leaf map node " + name);
+		def.leafMapDef(name).setTypeSpec(new ConfigDefinition.TypeSpec(name, ((LeafCNode) node).getType(), null, null, null, null));
+            } else {
+                //System.out.println("Adding basic node " + name);
+                if (node instanceof LeafCNode.IntegerLeaf) {
+                    addNode(def, (LeafCNode.IntegerLeaf) node);
+                } else if (node instanceof LeafCNode.LongLeaf) {
+                    addNode(def, (LeafCNode.LongLeaf) node);
+                } else if (node instanceof LeafCNode.BooleanLeaf) {
+                    addNode(def, (LeafCNode.BooleanLeaf) node);
+                } else if (node instanceof LeafCNode.DoubleLeaf) {
+                    addNode(def, (LeafCNode.DoubleLeaf) node);
+                    // Need to come before StringLeaf, since it is a subclass of StringLeaf
+                } else if (node instanceof LeafCNode.ReferenceLeaf) {
+                    addNode(def, (LeafCNode.ReferenceLeaf) node);
+                } else if (node instanceof LeafCNode.FileLeaf) {
+                    addNode(def, (LeafCNode.FileLeaf) node);
+                } else if (node instanceof LeafCNode.PathLeaf) {
+                    addNode(def, (LeafCNode.PathLeaf) node);
+                }else if (node instanceof LeafCNode.StringLeaf) {
+                    addNode(def, (LeafCNode.StringLeaf) node);
+                } else if (node instanceof LeafCNode.EnumLeaf) {
+                    addNode(def, (LeafCNode.EnumLeaf) node);
+                } else {
+                    System.err.println("Unknown node type for node with name " + name);
+                }
+            }
+        } else {
+            ConfigDefinition newDef;
+            if (node.isArray) {
+                if (node.getChildren() != null && node.getChildren().length > 0) {
+                    //System.out.println("\tAdding inner array node " + name);
+                    newDef = def.innerArrayDef(name);
+                    for (CNode childNode : node.getChildren()) {
+                        //System.out.println("\tChild node " + childNode.getName());
+                        addNode(newDef, childNode);
+                    }
+                }
+            } else if (node.isMap) {
+		//System.out.println("Adding struct map node " + name);
+		newDef = def.structMapDef(name);
+		if (node.getChildren() != null && node.getChildren().length > 0) {
+                    for (CNode childNode : node.getChildren()) {
+                        //System.out.println("\tChild node " + childNode.getName());
+                        addNode(newDef, childNode);
+                    }
+                }
+
+            } else {
+                //System.out.println("Adding struct node " + name);
+                newDef = def.structDef(name);
+                if (node.getChildren() != null && node.getChildren().length > 0) {
+                    for (CNode childNode : node.getChildren()) {
+                        //System.out.println("\tChild node " + childNode.getName());
+                        addNode(newDef, childNode);
+                    }
+                }
+            }
+        }
+    }
+
+
+    static void addNode(ConfigDefinition def, LeafCNode.IntegerLeaf leaf) {
+        if (leaf.getDefaultValue() != null) {
+            def.addIntDef(leaf.getName(), new Integer(leaf.getDefaultValue().getValue()));
+        } else {
+            def.addIntDef(leaf.getName());
+        }
+    }
+
+    static void addNode(ConfigDefinition def, LeafCNode.LongLeaf leaf) {
+        if (leaf.getDefaultValue() != null) {
+            def.addLongDef(leaf.getName(), new Long(leaf.getDefaultValue().getValue()));
+        } else {
+            def.addLongDef(leaf.getName());
+        }
+    }
+
+    static void addNode(ConfigDefinition def, LeafCNode.BooleanLeaf leaf) {
+        if (leaf.getDefaultValue() != null) {
+            def.addBoolDef(leaf.getName(), Boolean.valueOf(leaf.getDefaultValue().getValue()));
+        } else {
+            def.addBoolDef(leaf.getName());
+        }
+    }
+
+    static void addNode(ConfigDefinition def, LeafCNode.DoubleLeaf leaf) {
+        if (leaf.getDefaultValue() != null) {
+            def.addDoubleDef(leaf.getName(), new Double(leaf.getDefaultValue().getValue()));
+        } else {
+            def.addDoubleDef(leaf.getName());
+        }
+    }
+
+    static void addNode(ConfigDefinition def, LeafCNode.StringLeaf leaf) {
+        if (leaf.getDefaultValue() != null) {
+            def.addStringDef(leaf.getName(), leaf.getDefaultValue().getValue());
+        } else {
+            def.addStringDef(leaf.getName());
+        }
+    }
+
+    static void addNode(ConfigDefinition def, LeafCNode.ReferenceLeaf leaf) {
+        if (leaf.getDefaultValue() != null) {
+            def.addReferenceDef(leaf.getName(), leaf.getDefaultValue().getValue());
+        } else {
+            def.addReferenceDef(leaf.getName(), null);
+        }
+    }
+
+    static void addNode(ConfigDefinition def, LeafCNode.FileLeaf leaf) {
+        if (leaf.getDefaultValue() != null) {
+            def.addFileDef(leaf.getName(), leaf.getDefaultValue().getValue());
+        } else {
+            def.addFileDef(leaf.getName(), null);
+        }
+    }
+
+    static void addNode(ConfigDefinition def, LeafCNode.PathLeaf leaf) {
+        if (leaf.getDefaultValue() != null) {
+            def.addPathDef(leaf.getName(), leaf.getDefaultValue().getValue());
+        } else {
+            def.addPathDef(leaf.getName(), null);
+        }
+    }
+
+    static void addNode(ConfigDefinition def, LeafCNode.EnumLeaf leaf) {
+        if (leaf.getDefaultValue() != null) {
+            def.addEnumDef(leaf.getName(), Arrays.asList(leaf.getLegalValues()), leaf.getDefaultValue().getValue());
+        } else {
+            def.addEnumDef(leaf.getName(), Arrays.asList(leaf.getLegalValues()), null);
+        }
+    }
+
+    static String convertToEnumValueCommaSeparated(String[] enumValues) {
+        StringBuilder sb = new StringBuilder();
+        for (String s : enumValues) {
+            sb.append(s);
+            sb.append(", ");
+        }
+        int length = sb.length();
+        sb.delete(length - 2, length);
+        return sb.toString();
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigDefinitionKey.java b/config/src/main/java/com/yahoo/vespa/config/ConfigDefinitionKey.java
new file mode 100644
index 00000000000..29c39ef0ab0
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ConfigDefinitionKey.java
@@ -0,0 +1,58 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+/**
+ * Represents one config definition key (name, namespace)
+ *
+ * @author vegardh
+ */
+public class ConfigDefinitionKey {
+
+    private final String name;
+    private final String namespace;
+
+    /**
+     * Creates a config definition key.
+     *  @param name      config definition name
+     * @param namespace config definition namespace
+     */
+    public ConfigDefinitionKey(String name, String namespace) {
+        this.name = name;
+        this.namespace = namespace;
+    }
+
+    public ConfigDefinitionKey(ConfigKey<?> key) {
+        this(key.getName(), key.getNamespace());
+    }
+
+    public String getName() {
+        return name;
+    }
+
+    public String getNamespace() {
+        return namespace;
+    }
+
+    @Override
+    public boolean equals(Object oth) {
+        if (!(oth instanceof ConfigDefinitionKey)) {
+            return false;
+        }
+        ConfigDefinitionKey other = (ConfigDefinitionKey) oth;
+        return name.equals(other.getName()) &&
+                namespace.equals(other.getNamespace());
+    }
+
+    @Override
+    public int hashCode() {
+        return namespace.hashCode() + name.hashCode();
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append(namespace).append(".").append(name);
+        return sb.toString();
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigDefinitionSet.java b/config/src/main/java/com/yahoo/vespa/config/ConfigDefinitionSet.java
new file mode 100644
index 00000000000..5e5f8db2711
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ConfigDefinitionSet.java
@@ -0,0 +1,64 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.codegen.CNode;
+import com.yahoo.log.LogLevel;
+
+import java.util.Map;
+import java.util.concurrent.ConcurrentHashMap;
+
+/**
+ * Class to hold config definitions and resolving requests for the correct definition
+ *
+ * @author Harald Musum &lt;musum@yahoo-inc.com&gt;
+ * @since 5.1
+ */
+public class ConfigDefinitionSet {
+    private static final java.util.logging.Logger log = java.util.logging.Logger.getLogger(ConfigDefinitionSet.class.getName());
+
+    private final Map<ConfigDefinitionKey, ConfigDefinition> defs = new ConcurrentHashMap<ConfigDefinitionKey, ConfigDefinition>();
+
+    public ConfigDefinitionSet() {
+
+    }
+
+    public void add(ConfigDefinitionKey key, ConfigDefinition def) {
+        log.log(LogLevel.DEBUG, "Adding to set: " + key);
+        defs.put(key, def);
+    }
+
+    /**
+     * Returns a ConfigDefinition from the set matching the given <code>key</code>. If no ConfigDefinition
+     * is found in the set, it will try to find a ConfigDefinition with same name in the default namespace.
+     * @param key a {@link ConfigDefinitionKey}
+     * @return a ConfigDefinition if found, else null
+     */
+    public ConfigDefinition get(ConfigDefinitionKey key) {
+        log.log(LogLevel.DEBUG, "Getting from set " + defs + " for key " + key);
+        ConfigDefinition ret = defs.get(key);
+        if (ret == null) {
+            // Return entry if we fallback to default namespace
+            log.log(LogLevel.DEBUG, "Found no def for key " + key + ", trying to find def with same name in default namespace");
+            for (Map.Entry<ConfigDefinitionKey, ConfigDefinition> entry : defs.entrySet()) {
+                if (key.getName().equals(entry.getKey().getName()) && entry.getKey().getNamespace().equals(CNode.DEFAULT_NAMESPACE)) {
+                    return entry.getValue();
+                }
+            }
+        }
+        return ret;
+    }
+
+    public int size() {
+        return defs.size();
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        for (ConfigDefinitionKey key : defs.keySet()) {
+                sb.append(key.toString()).append("\n");
+        }
+        return sb.toString();
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigFileFormat.java b/config/src/main/java/com/yahoo/vespa/config/ConfigFileFormat.java
new file mode 100644
index 00000000000..1ce81abd57a
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ConfigFileFormat.java
@@ -0,0 +1,233 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.codegen.CNode;
+import com.yahoo.config.codegen.InnerCNode;
+import com.yahoo.config.codegen.LeafCNode;
+import com.yahoo.slime.*;
+import com.yahoo.text.Utf8;
+import com.yahoo.vespa.config.util.ConfigUtils;
+
+import java.io.*;
+import java.util.Stack;
+
+/**
+ * @author lulf
+ * @since 5.1
+ */
+public class ConfigFileFormat implements SlimeFormat, ObjectTraverser {
+    private final InnerCNode root;
+    private DataOutputStream out = null;
+    private Stack<Node> nodeStack;
+
+    public ConfigFileFormat(InnerCNode root) {
+        this.root = root;
+        this.nodeStack = new Stack<>();
+    }
+
+    private void printPrefix() throws IOException {
+        for (Node node : nodeStack) {
+            CNode cnode = node.node;
+            if (cnode != root) {
+                encodeString(cnode.getName());
+                if (cnode.isArray) {
+                    encodeString("[" + node.arrayIndex + "]");
+                    if (!(cnode instanceof LeafCNode)) {
+                        encodeString(".");
+                    }
+                } else if (cnode.isMap) {
+                    encodeString("{\"" + node.mapKey + "\"}");
+                    if (!(cnode instanceof LeafCNode)) {
+                        encodeString(".");
+                    }
+                } else if (cnode instanceof LeafCNode) {
+                    encodeString("");
+                } else {
+                    encodeString(".");
+                }
+            }
+        }
+        encodeString(" ");
+    }
+
+    private void encode(Inspector inspector, CNode node) throws IOException {
+        switch (inspector.type()) {
+            case BOOL:
+                encodeValue(String.valueOf(inspector.asBool()), (LeafCNode) node);
+                return;
+            case LONG:
+                encodeValue(String.valueOf(inspector.asLong()), (LeafCNode) node);
+                return;
+            case DOUBLE:
+                encodeValue(String.valueOf(inspector.asDouble()), (LeafCNode) node);
+                return;
+            case STRING:
+                encodeValue(inspector.asString(), (LeafCNode) node);
+                return;
+            case ARRAY:
+                encodeArray(inspector, node);
+                return;
+            case OBJECT:
+                if (node.isMap) {
+                    encodeMap(inspector, node);
+                } else {
+                    encodeObject(inspector, node);
+                }
+                return;
+            case NIX:
+            case DATA:
+                throw new IllegalArgumentException("Illegal config format supplied. Unknown type for field '" + node.getName() + "'");
+        }
+        throw new RuntimeException("Should not be reached");
+    }
+
+    private void encodeMap(Inspector inspector, final CNode node) {
+        inspector.traverse(new ObjectTraverser() {
+            @Override
+            public void field(String name, Inspector inspector) {
+                try {
+                    nodeStack.push(new Node(node, -1, name));
+                    if (inspector.type().equals(Type.OBJECT)) {
+                        encodeObject(inspector, node);
+                    } else {
+                        encode(inspector, node);
+                    }
+                    nodeStack.pop();
+                } catch (IOException e) {
+                    throw new RuntimeException(e);
+                }
+            }
+        });
+    }
+
+    private void encodeArray(Inspector inspector, final CNode node) {
+        inspector.traverse(new ArrayTraverser() {
+            @Override
+            public void entry(int idx, Inspector inspector) {
+                try {
+                    nodeStack.push(new Node(node, idx, ""));
+                    encode(inspector, node);
+                    nodeStack.pop();
+                } catch (IOException e) {
+                    throw new RuntimeException(e);
+                }
+            }
+        });
+
+    }
+
+    private void encodeObject(Inspector inspector, CNode node) {
+        if (!node.isArray && !node.isMap) {
+            nodeStack.push(new Node(node));
+            inspector.traverse(this);
+            nodeStack.pop();
+        } else {
+            inspector.traverse(this);
+        }
+    }
+
+    private void encodeValue(String value, LeafCNode node) throws IOException {
+        printPrefix();
+        try {
+            if (node instanceof LeafCNode.StringLeaf) {
+                encodeStringQuoted(value);
+            } else if (node instanceof LeafCNode.IntegerLeaf) {
+                //Integer.parseInt(value);
+                encodeString(value);
+            } else if (node instanceof LeafCNode.LongLeaf) {
+                //Long.parseLong(value);
+                encodeString(value);
+            } else if (node instanceof LeafCNode.DoubleLeaf) {
+                //Double.parseDouble(value);
+                encodeString(value);
+            } else if (node instanceof LeafCNode.BooleanLeaf) {
+                encodeString(String.valueOf(Boolean.parseBoolean(value)));
+            } else if (node instanceof LeafCNode.EnumLeaf) {
+                // LeafCNode.EnumLeaf enumNode = (LeafCNode.EnumLeaf) node;
+                // TODO: Reenable this when we can return illegal config id.
+                // checkLegalEnumValue(enumNode, value);
+                encodeString(value);
+            } else {
+                encodeStringQuoted(value);
+            }
+            encodeString("\n");
+        } catch (Exception e) {
+            throw new IllegalArgumentException("Unable to serialize field '" + node.getFullName() + "': ", e);
+        }
+    }
+
+    private void checkLegalEnumValue(LeafCNode.EnumLeaf enumNode, String value) {
+        boolean found = false;
+        for (String legalVal : enumNode.getLegalValues()) {
+            if (legalVal.equals(value)) {
+                found = true;
+            }
+        }
+        if (!found)
+            throw new IllegalArgumentException("Illegal enum value '" + value + "'");
+    }
+
+    private void encodeStringQuoted(String s) throws IOException {
+        encodeString("\"" + escapeString(s) + "\"");
+    }
+
+    private String escapeString(String s) {
+        return ConfigUtils.escapeConfigFormatValue(s);
+    }
+
+    private void encodeString(String s) throws IOException {
+        out.write(Utf8.toBytes(s));
+    }
+
+    @Override
+    public void encode(OutputStream os, Slime slime) throws IOException {
+        encode(os, slime.get());
+    }
+
+    public void encode(OutputStream os, Inspector inspector) throws IOException {
+        this.out = new DataOutputStream(os);
+        this.nodeStack = new Stack<>();
+        nodeStack.push(new Node(root));
+        encode(inspector, root);
+    }
+
+    @Override
+    public void decode(InputStream is, Slime slime) throws IOException {
+        throw new UnsupportedOperationException("decode is not supported");
+    }
+
+    @Override
+    public void field(String fieldName,  Inspector inspector) {
+        try {
+            Node parent = nodeStack.peek();
+            CNode child = parent.node.getChild(fieldName);
+            if (child == null) {
+                return; // Skip this field to optimistic
+            }
+            if (!child.isArray && !child.isMap && child instanceof LeafCNode) {
+                nodeStack.push(new Node(child));
+                encode(inspector, child);
+                nodeStack.pop();
+            } else {
+                encode(inspector, child);
+            }
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private class Node {
+        final int arrayIndex;
+        final String mapKey;
+        final CNode node;
+        Node(CNode node, int arrayIndex, String mapKey) {
+            this.node = node;
+            this.arrayIndex = arrayIndex;
+            this.mapKey = mapKey;
+        }
+
+        public Node(CNode node) {
+            this(node, -1, "");
+        }
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigHelper.java b/config/src/main/java/com/yahoo/vespa/config/ConfigHelper.java
new file mode 100644
index 00000000000..a1469b746dc
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ConfigHelper.java
@@ -0,0 +1,51 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.subscription.ConfigSourceSet;
+
+/**
+ * Helper class for config applications (currently ConfigManager and ConfigProxy).
+ *
+ * @author <a href="gv@yahoo-inc.com">G. Voldengen</a>
+ */
+public class ConfigHelper {
+    private final JRTConnectionPool jrtConnectionPool;
+    private TimingValues timingValues;
+
+    /**
+     * @param configSourceSet  The set of config sources for this helper.
+     */
+    public ConfigHelper(ConfigSourceSet configSourceSet) {
+        this(configSourceSet, new TimingValues());
+    }
+
+    /**
+     * @param configSourceSet  The set of config sources for this helper.
+     * @param timingValues values for timeouts and delays, see {@link TimingValues}
+     */
+    public ConfigHelper(ConfigSourceSet configSourceSet, TimingValues timingValues) {
+        jrtConnectionPool = new JRTConnectionPool(configSourceSet);
+        this.timingValues = timingValues;
+    }
+
+    /**
+     * @return the config sources (remote servers and/or proxies) in this helper's connection pool.
+     */
+    public ConfigSourceSet getConfigSourceSet() {
+        return jrtConnectionPool.getSourceSet();
+    }
+
+    /**
+     * @return the connection pool for this config helper.
+     */
+    public JRTConnectionPool getConnectionPool() {
+        return jrtConnectionPool;
+    }
+
+    /**
+     * @return the timing values for this config helper.
+     */
+    public TimingValues getTimingValues() {
+        return timingValues;
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigKey.java b/config/src/main/java/com/yahoo/vespa/config/ConfigKey.java
new file mode 100755
index 00000000000..1e8ba43d649
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ConfigKey.java
@@ -0,0 +1,138 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.ConfigurationRuntimeException;
+import com.yahoo.config.codegen.CNode;
+import edu.umd.cs.findbugs.annotations.NonNull;
+import edu.umd.cs.findbugs.annotations.Nullable;
+
+/**
+ * Class for holding the key when doing cache look-ups and other management of config instances.
+ *
+ * @author <a href="musum@yahoo-inc.com">Harald Musum</a>
+ */
+public class ConfigKey<CONFIGCLASS extends ConfigInstance> implements Comparable<ConfigKey<?>> {
+
+    @NonNull
+    private final String name;
+    @NonNull
+    private final String configId;
+    @NonNull
+    private final String namespace;
+
+    // The two fields below are only set when ConfigKey is constructed from a config class. Can be null
+    private final Class<CONFIGCLASS> configClass;
+    private final String md5; // config definition md5
+
+    /**
+     * Constructs new key
+     *
+     * @param name           config definition name
+     * @param configIdString Can be null.
+     * @param namespace      namespace for this config definition
+     */
+    public ConfigKey(String name, String configIdString, String namespace) {
+        this(name, configIdString, namespace, null, null);
+    }
+
+    /**
+     * Creates a new instance from the given class and configId
+     *
+     * @param clazz          Config class
+     * @param configIdString config id, can be null.
+     */
+    public ConfigKey(Class<CONFIGCLASS> clazz, String configIdString) {
+        this(getFieldFromClass(clazz, "CONFIG_DEF_NAME"),
+                configIdString, getFieldFromClass(clazz, "CONFIG_DEF_NAMESPACE"), getFieldFromClass(clazz, "CONFIG_DEF_MD5"), clazz);
+    }
+
+    public ConfigKey(String name, String configIdString, String namespace, String defMd5, Class<CONFIGCLASS> clazz) {
+        if (name == null)
+            throw new ConfigurationRuntimeException("Config name must be non-null!");
+        this.name = name;
+        this.configId = (configIdString == null) ? "" : configIdString;
+        this.namespace = (namespace == null) ? CNode.DEFAULT_NAMESPACE : namespace;
+        this.md5 = (defMd5 == null) ? "" : defMd5;
+        this.configClass = clazz;
+    }
+
+    /**
+     * Comparison sort order: namespace, name, configId.
+     */
+    @Override
+    public int compareTo(ConfigKey<?> o) {
+        if (!o.getNamespace().equals(getNamespace())) return getNamespace().compareTo(o.getNamespace());
+        if (!o.getName().equals(getName())) return getName().compareTo(o.getName());
+        return getConfigId().compareTo(o.getConfigId());
+    }
+
+    private static String getFieldFromClass(Class<?> clazz, String fieldName) {
+        try {
+            return (String) clazz.getField(fieldName).get(null);
+        } catch (NoSuchFieldException | IllegalAccessException e) {
+            throw new ConfigurationRuntimeException("No such field '" + fieldName + "' in class " + clazz + ", or could not access field.", e);
+        }
+    }
+
+    public boolean equals(Object o) {
+        if (o == this) {
+            return true;
+        }
+        if (!(o instanceof ConfigKey)) {
+            return false;
+        }
+        ConfigKey<?> key = (ConfigKey) o;
+        return (name.equals(key.name) &&
+                configId.equals(key.configId) &&
+                namespace.equals(key.namespace));
+    }
+
+    public int hashCode() {
+        int hash = 17;
+        hash = 37 * hash + name.hashCode();
+        hash = 37 * hash + configId.hashCode();
+        hash = 37 * hash + namespace.hashCode();
+        return hash;
+    }
+
+    @NonNull
+    public String getName() {
+        return name;
+    }
+
+    @NonNull
+    public String getConfigId() {
+        return configId;
+    }
+
+    @NonNull
+    public String getNamespace() {
+        return namespace;
+    }
+
+    @Nullable
+    public Class<CONFIGCLASS> getConfigClass() {
+        return configClass;
+    }
+
+    @Nullable
+    public String getMd5() {
+        return md5;
+    }
+
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append("name=");
+        sb.append(name);
+        sb.append(",namespace=");
+        sb.append(namespace);
+        sb.append(",configId=");
+        sb.append(configId);
+        return sb.toString();
+    }
+
+    public static ConfigKey<?> createFull(String name, String configId, String namespace, String md5) {
+        return new ConfigKey<>(name, configId, namespace, md5, null);
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigPayload.java b/config/src/main/java/com/yahoo/vespa/config/ConfigPayload.java
new file mode 100644
index 00000000000..a4ac34e65aa
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ConfigPayload.java
@@ -0,0 +1,100 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.codegen.InnerCNode;
+import com.yahoo.config.subscription.ConfigInstanceSerializer;
+import com.yahoo.config.subscription.ConfigInstanceUtil;
+import com.yahoo.slime.JsonDecoder;
+import com.yahoo.slime.JsonFormat;
+import com.yahoo.slime.Slime;
+import com.yahoo.slime.SlimeFormat;
+import com.yahoo.text.Utf8Array;
+import com.yahoo.text.Utf8String;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+
+/**
+ * A class that holds a representation of a config payload.
+ *
+ * @author lulf
+ * @since 5.1.6
+ */
+public class ConfigPayload {
+    private final Slime slime;
+
+    public ConfigPayload(Slime slime) {
+        this.slime = slime;
+    }
+
+    public static ConfigPayload fromInstance(ConfigInstance instance) {
+        Slime slime = new Slime();
+        ConfigInstanceSerializer serializer = new ConfigInstanceSerializer(slime);
+        ConfigInstance.serialize(instance, serializer);
+        return new ConfigPayload(slime);
+    }
+
+    public static ConfigPayload fromBuilder(ConfigPayloadBuilder builder) {
+        Slime slime = new Slime();
+        builder.resolve(slime.setObject());
+        return new ConfigPayload(slime);
+    }
+
+    public Slime getSlime() {
+        return slime;
+    }
+
+    public void serialize(OutputStream os, SlimeFormat format) throws IOException {
+        format.encode(os, slime);
+    }
+
+    @Override
+    public String toString() {
+        return toString(false);
+    }
+
+    public String toString(boolean compact) {
+        return toUtf8Array(compact).toString();
+    }
+
+    public ConfigPayload applyDefaultsFromDef(InnerCNode clientDef) {
+        DefaultValueApplier defaultValueApplier = new DefaultValueApplier();
+        defaultValueApplier.applyDefaults(slime, clientDef);
+        return this;
+    }
+
+    public static ConfigPayload empty() {
+        Slime slime = new Slime();
+        slime.setObject();
+        return new ConfigPayload(slime);
+    }
+
+    public static ConfigPayload fromString(String jsonString) {
+        return fromUtf8Array(new Utf8String(jsonString));
+    }
+
+    public boolean isEmpty() {
+        return !slime.get().valid() || slime.get().children() == 0;
+    }
+
+    public Utf8Array toUtf8Array(boolean compact) {
+        ByteArrayOutputStream os = new ByteArrayOutputStream(10000);
+        try {
+            new JsonFormat(compact).encode(os, slime);
+            os.close();
+        } catch (IOException e) {
+            e.printStackTrace();
+        }
+        return new Utf8Array(os.toByteArray());
+    }
+
+    public static ConfigPayload fromUtf8Array(Utf8Array payload) {
+        return new ConfigPayload(new JsonDecoder().decode(new Slime(), payload.getBytes()));
+    }
+
+    public <ConfigType extends ConfigInstance> ConfigType toInstance(Class<ConfigType> clazz, String configId) {
+        return ConfigInstanceUtil.getNewInstance(clazz, configId, this);
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigPayloadApplier.java b/config/src/main/java/com/yahoo/vespa/config/ConfigPayloadApplier.java
new file mode 100644
index 00000000000..2b17305252f
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ConfigPayloadApplier.java
@@ -0,0 +1,498 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.ConfigBuilder;
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.FileReference;
+import com.yahoo.log.LogLevel;
+import com.yahoo.yolean.Exceptions;
+import com.yahoo.slime.ArrayTraverser;
+import com.yahoo.slime.Inspector;
+import com.yahoo.slime.ObjectTraverser;
+import com.yahoo.slime.Type;
+import com.yahoo.text.Utf8;
+
+import java.io.File;
+import java.lang.reflect.Constructor;
+import java.lang.reflect.Field;
+import java.lang.reflect.InvocationTargetException;
+import java.lang.reflect.Method;
+import java.lang.reflect.ParameterizedType;
+import java.nio.file.Path;
+import java.util.*;
+import java.util.logging.Logger;
+
+/**
+ * A utility class that can be used to apply a payload to a config builder.
+ *
+ * TODO: This can be refactored a lot, since many of the reflection methods are duplicated
+ *
+ * @author lulf, musum, tonyv
+ * @since 5.1.6
+ */
+public class ConfigPayloadApplier<T extends ConfigInstance.Builder> {
+    private final static Logger log = Logger.getLogger(ConfigPayloadApplier.class.getPackage().getName());
+
+    private final ConfigInstance.Builder rootBuilder;
+    private final ConfigTransformer.PathAcquirer pathAcquirer;
+    private final Stack<NamedBuilder> stack = new Stack<>();
+
+    public ConfigPayloadApplier(T builder) {
+        this(builder, new IdentityPathAcquirer());
+    }
+
+    public ConfigPayloadApplier(T builder, ConfigTransformer.PathAcquirer pathAcquirer) {
+        this.rootBuilder = builder;
+        this.pathAcquirer = pathAcquirer;
+        debug("rootBuilder=" + rootBuilder);
+    }
+
+    public void applyPayload(ConfigPayload payload) {
+        stack.push(new NamedBuilder(rootBuilder));
+        try {
+            handleValue(payload.getSlime().get());
+        } catch (Exception e) {
+            throw new RuntimeException("Not able to create config builder for payload:" + payload.toString() +
+                    ", " + Exceptions.toMessageString(e), e);
+        }
+    }
+
+    private void handleValue(Inspector inspector) {
+        switch (inspector.type()) {
+            case NIX:
+            case BOOL:
+            case LONG:
+            case DOUBLE:
+            case STRING:
+            case DATA:
+                handleLeafValue(inspector);
+                break;
+            case ARRAY:
+                handleARRAY(inspector);
+                break;
+            case OBJECT:
+                handleOBJECT(inspector);
+                break;
+            default:
+                assert false : "Should not be reached";
+        }
+    }
+
+    private void handleARRAY(Inspector inspector) {
+        trace("Array");
+        inspector.traverse(new ArrayTraverser() {
+            @Override
+            public void entry(int idx, Inspector inspector) {
+                handleArrayEntry(idx, inspector);
+            }
+        });
+    }
+
+    private void handleArrayEntry(int idx, Inspector inspector) {
+        try {
+            trace("entry, idx=" + idx);
+            trace("top of stack=" + stack.peek().toString());
+            String name = stack.peek().nameStack().peek();
+            if (inspector.type().equals(Type.OBJECT)) {
+                stack.push(createBuilder(stack.peek(), name));
+            }
+            handleValue(inspector);
+            if (inspector.type().equals(Type.OBJECT)) {
+                stack.peek().nameStack().pop();
+            }
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private void handleOBJECT(Inspector inspector) {
+        trace("Object");
+        printStack();
+
+        inspector.traverse(new ObjectTraverser() {
+            @Override
+            public void field(String name, Inspector inspector) {
+                handleObjectEntry(name, inspector);
+            }
+        });
+
+        trace("Should pop a builder from stack");
+        NamedBuilder builder = stack.pop();
+        printStack();
+
+        // Need to set e.g struct(Struct.Builder) here
+        if (!stack.empty()) {
+            trace("builder= " + builder);
+            try {
+                invokeSetter(stack.peek().builder, builder.peekName(), builder.builder);
+            } catch (Exception e) {
+                throw new RuntimeException("Could not set '" + builder.peekName() +
+                        "' for value '" + builder.builder() + "'", e);
+            }
+        }
+    }
+
+    private void handleObjectEntry(String name, Inspector inspector) {
+        try {
+            trace("field, name=" + name);
+            NamedBuilder parentBuilder = stack.peek();
+            if (inspector.type().equals(Type.OBJECT)) {
+                if (isMapField(parentBuilder, name)) {
+                    parentBuilder.nameStack().push(name);
+                    handleMap(inspector);
+                    parentBuilder.nameStack().pop();
+                    return;
+                } else {
+                    stack.push(createBuilder(parentBuilder, name));
+                }
+            } else if (inspector.type().equals(Type.ARRAY)) {
+                for (int i = 0; i < inspector.children(); i++) {
+                    trace("Pushing " + name);
+                    parentBuilder.nameStack().push(name);
+                }
+            } else {  // leaf
+                parentBuilder.nameStack().push(name);
+            }
+            handleValue(inspector);
+        } catch (Exception e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    private void handleMap(Inspector inspector) {
+        inspector.traverse(new ObjectTraverser() {
+            @Override
+            public void field(String name, Inspector inspector) {
+                switch (inspector.type()) {
+                case OBJECT:
+                    handleInnerMap(name, inspector);
+                    break;
+                case ARRAY:
+                    throw new IllegalArgumentException("Never herd of array inside maps before");
+                default:
+                    setMapLeafValue(name, getValueFromInspector(inspector));
+                    break;
+                }
+            }
+        });
+    }
+
+    private void handleInnerMap(String name, Inspector inspector) {
+        NamedBuilder builder = createBuilder(stack.peek(), stack.peek().peekName());
+        setMapLeafValue(name, builder.builder());
+        stack.push(builder);
+        inspector.traverse(new ObjectTraverser() {
+            @Override
+            public void field(String name, Inspector inspector) {
+                handleObjectEntry(name, inspector);
+            }
+        });
+        stack.pop();
+    }
+
+    private void setMapLeafValue(String key, Object value) {
+        NamedBuilder parent = stack.peek();
+        ConfigBuilder builder = parent.builder();
+        String methodName = parent.peekName();
+        //trace("class to obtain method from: " + builder.getClass().getName());
+        try {
+            // Need to convert reference into actual path if 'path' type is used
+            if (isPathField(builder, methodName)) {
+                FileReference wrappedPath = resolvePath((String)value);
+                invokeSetter(builder, methodName, key, wrappedPath);
+            } else {
+                invokeSetter(builder, methodName, key, value);
+            }
+        } catch (InvocationTargetException | IllegalAccessException e) {
+            throw new RuntimeException("Name: " + methodName + ", value '" + value + "'", e);
+        } catch (NoSuchMethodException e) {
+            log.log(LogLevel.INFO, "Skipping unknown field " + methodName + " in " + rootBuilder);
+        }
+    }
+
+    private boolean isMapField(NamedBuilder parentBuilder, String name) {
+        ConfigBuilder builder = parentBuilder.builder();
+        try {
+            Field f = builder.getClass().getField(name);
+            return f.getType().getName().equals("java.util.Map");
+        } catch (Exception e) {
+            return false;
+        }
+    }
+
+    NamedBuilder createBuilder(NamedBuilder parentBuilder, String name) {
+        Object builder = parentBuilder.builder();
+        Object newBuilder = getBuilderForStruct(findBuilderName(name), name, builder.getClass().getDeclaringClass());
+        trace("New builder for " + name + "=" + newBuilder);
+        trace("Pushing builder for " + name + "=" + newBuilder + " onto stack");
+        return new NamedBuilder((ConfigBuilder) newBuilder, name);
+    }
+
+    private void handleLeafValue(Inspector value) {
+        trace("String ");
+        printStack();
+        NamedBuilder peek = stack.peek();
+        trace("popping name stack");
+        String name = peek.nameStack().pop();
+        printStack();
+        ConfigBuilder builder = peek.builder();
+        trace("name=" + name + ",builder=" + builder + ",value=" + value.toString());
+        setValueForLeafNode(builder, name, value);
+    }
+
+    // Sets values for leaf nodes (uses private accessors that take string as argument)
+    private void setValueForLeafNode(Object builder, String methodName, Inspector value) {
+        try {
+            // Need to convert reference into actual path if 'path' type is used
+            if (isPathField(builder, methodName)) {
+                FileReference wrappedPath = resolvePath(Utf8.toString(value.asUtf8()));
+                invokeSetter(builder, methodName, wrappedPath);
+            } else {
+                Object object = getValueFromInspector(value);
+                invokeSetter(builder, methodName, object);
+            }
+        } catch (InvocationTargetException | IllegalAccessException e) {
+            throw new RuntimeException("Name: " + methodName + ", value '" + value + "'", e);
+        } catch (NoSuchMethodException e) {
+            log.log(LogLevel.INFO, "Skipping unknown field " + methodName + " in " + builder.getClass());
+        }
+    }
+
+    private FileReference resolvePath(String value) {
+        Path path = pathAcquirer.getPath(newFileReference(value));
+        return newFileReference(path.toString());
+    }
+
+    private FileReference newFileReference(String fileReference) {
+        try {
+            Constructor<FileReference> constructor = FileReference.class.getDeclaredConstructor(String.class);
+            constructor.setAccessible(true);
+            return constructor.newInstance(fileReference);
+        } catch (Exception e) {
+            throw new RuntimeException("Failed invoking FileReference constructor.", e);
+        }
+    }
+
+    private final Map<String, Method> methodCache = new HashMap<>();
+    private static String methodCacheKey(Object builder, String methodName, Object[] params) {
+        StringBuilder sb = new StringBuilder();
+        sb.append(builder.getClass().getName())
+          .append(".")
+          .append(methodName);
+        for (Object param : params) {
+            sb.append(".").append(param.getClass().getName());
+        }
+        return sb.toString();
+    }
+
+    private Method lookupSetter(Object builder, String methodName, Object ... params) throws NoSuchMethodException {
+        Class<?>[] parameterTypes = new Class<?>[params.length];
+        for (int i = 0; i < params.length; i++) {
+            parameterTypes[i] = params[i].getClass();
+        }
+        Method method = builder.getClass().getDeclaredMethod(methodName, parameterTypes);
+        method.setAccessible(true);
+        trace("method=" + method + ",params=" + params);
+        return method;
+    }
+
+    private void invokeSetter(Object builder, String methodName, Object ... params) throws NoSuchMethodException, IllegalAccessException, InvocationTargetException {
+        // TODO: Does not work for native types.
+        String key = methodCacheKey(builder, methodName, params);
+        Method method = methodCache.get(key);
+        if (method == null) {
+            method = lookupSetter(builder, methodName, params);
+            methodCache.put(key, method);
+        }
+        method.invoke(builder, params);
+    }
+
+    private Object getValueFromInspector(Inspector inspector) {
+        switch (inspector.type()) {
+            case STRING:
+                return Utf8.toString(inspector.asUtf8());
+            case LONG:
+                return String.valueOf(inspector.asLong());
+            case DOUBLE:
+                return String.valueOf(inspector.asDouble());
+            case NIX:
+                return null;
+            case BOOL:
+                return String.valueOf(inspector.asBool());
+            case DATA:
+                return String.valueOf(inspector.asData());
+        }
+        throw new IllegalArgumentException("Unhandled type " + inspector.type());
+    }
+
+
+    /**
+     * Checks whether or not this field is of type 'path', in which
+     * case some special handling might be needed. Caches the result.
+     */
+    private Set<String> pathFieldSet = new HashSet<>();
+    private boolean isPathField(Object builder, String methodName) {
+        String key = pathFieldKey(builder, methodName);
+        if (pathFieldSet.contains(key)) {
+            return true;
+        }
+        boolean isPath = false;
+        try {
+            Field field = builder.getClass().getDeclaredField(methodName);
+            //Paths are stored as FileReference in Builder.
+            java.lang.reflect.Type fieldType = field.getGenericType();
+            if (fieldType instanceof Class<?> && fieldType == FileReference.class) {
+                isPath = true;
+            } else if (fieldType instanceof ParameterizedType) {
+                isPath = isParameterizedWithPath((ParameterizedType) fieldType);
+            }
+        } catch (NoSuchFieldException e) {
+        }
+        if (isPath) {
+            pathFieldSet.add(key);
+        }
+        return isPath;
+    }
+
+    private static String pathFieldKey(Object builder, String methodName) {
+        return builder.getClass().getName() + "." + methodName;
+    }
+
+    private boolean isParameterizedWithPath(ParameterizedType fieldType) {
+        int numTypeArgs = fieldType.getActualTypeArguments().length;
+        if (numTypeArgs > 0)
+             return fieldType.getActualTypeArguments()[numTypeArgs - 1] == FileReference.class;
+        return false;
+    }
+
+
+    private String findBuilderName(String name) {
+        StringBuilder sb = new StringBuilder();
+        sb.append(name.substring(0, 1).toUpperCase()).append(name.substring(1));
+        return sb.toString();
+    }
+
+    private Constructor<?> lookupBuilderForStruct(String builderName, String name, Class<?> currentClass) {
+        final String currentClassName = currentClass.getName();
+        trace("builderName=" + builderName + ", name=" + name + ",current class=" + currentClassName);
+        Class<?> structClass = findClass(currentClass, currentClassName + "$" + builderName);
+        Class<?> structBuilderClass = findClass(structClass, currentClassName + "$" + builderName + "$Builder");
+        try {
+            return structBuilderClass.getDeclaredConstructor(new Class<?>[]{});
+        } catch (NoSuchMethodException e) {
+            throw new RuntimeException("Could not create class '" + "'" + structBuilderClass.getName() + "'");
+        }
+    }
+
+    /**
+     * Finds a nested class or builder class with the given <code>name</code>name in <code>clazz</code>
+     * @param clazz a Class
+     * @param name a name
+     * @return class found, or throws an exception is no class is found
+     */
+    private Class<?> findClass(Class<?> clazz, String name) {
+        for (Class<?> cls : clazz.getDeclaredClasses()) {
+            if (cls.getName().equals(name)) {
+                trace("Found class " + cls.getName());
+                return cls;
+            }
+        }
+        throw new RuntimeException("could not find class representing '" + printCurrentConfigName() + "'");
+    }
+
+    private final Map<String, Constructor<?>> constructorCache = new HashMap<>();
+    private static String constructorCacheKey(String builderName, String name, Class<?> currentClass) {
+        return builderName + "." + name + "." + currentClass.getName();
+    }
+
+    private Object getBuilderForStruct(String builderName, String name, Class<?> currentClass) {
+        String key = constructorCacheKey(builderName, name, currentClass);
+        Constructor<?> ctor = constructorCache.get(key);
+        if (ctor == null) {
+            ctor = lookupBuilderForStruct(builderName, name, currentClass);
+            constructorCache.put(key, ctor);
+        }
+        Object builder;
+        try {
+            builder = ctor.newInstance();
+        } catch (Exception e) {
+            throw new RuntimeException("Could not create class '" + "'" + ctor.getDeclaringClass().getName() + "'");
+        }
+        return builder;
+    }
+
+    private String printCurrentConfigName() {
+        StringBuilder sb = new StringBuilder();
+        ArrayList<String> stackElements = new ArrayList<>();
+        Stack<String> nameStack = stack.peek().nameStack();
+        while (!nameStack.empty()) {
+            stackElements.add(nameStack.pop());
+        }
+        Collections.reverse(stackElements);
+        for (String s : stackElements) {
+            sb.append(s);
+            sb.append(".");
+        }
+        sb.deleteCharAt(sb.length() - 1); // remove last .
+        return sb.toString();
+    }
+
+    private void debug(String message) {
+        if (log.isLoggable(LogLevel.DEBUG)) {
+            log.log(LogLevel.DEBUG, message);
+        }
+    }
+
+    private void trace(String message) {
+        if (log.isLoggable(LogLevel.SPAM)) {
+            log.log(LogLevel.SPAM, message);
+        }
+    }
+
+    private void printStack() {
+        trace("stack=" + stack.toString());
+    }
+
+    /**
+     * A class that holds a builder and a stack of names
+     */
+    private static class NamedBuilder {
+        private ConfigBuilder builder;
+        private final Stack<String> names = new Stack<>(); // if empty, the builder is the root builder
+
+        NamedBuilder(ConfigBuilder builder) {
+            this.builder = builder;
+        }
+
+        NamedBuilder(ConfigBuilder builder, String name) {
+            this(builder);
+            names.push(name);
+        }
+
+        ConfigBuilder builder() {
+            return builder;
+        }
+
+        String peekName() {
+            return names.peek();
+        }
+
+        Stack<String> nameStack() {
+            return names;
+        }
+
+        @Override
+        public String toString() {
+            StringBuilder sb = new StringBuilder();
+            sb.append(builder() == null ? "null" : builder.toString()).append(" names=").append(names);
+            return sb.toString();
+        }
+    }
+
+    static class IdentityPathAcquirer implements ConfigTransformer.PathAcquirer {
+        @Override
+        public Path getPath(FileReference fileReference) {
+            return new File(fileReference.value()).toPath();
+        }
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigPayloadBuilder.java b/config/src/main/java/com/yahoo/vespa/config/ConfigPayloadBuilder.java
new file mode 100644
index 00000000000..409bf307a34
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ConfigPayloadBuilder.java
@@ -0,0 +1,527 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.slime.*;
+
+import java.util.*;
+
+/**
+ * Helper class for building Slime config payloads, while supporting referring to payloads with their indices. The
+ * builder does not care about config field types. This is resolved by the actual config type consumer created
+ * from the Slime tree.
+ *
+ * TODO: Add toString
+ * @author lulf
+ * @since 5.1
+ */
+public class ConfigPayloadBuilder {
+    private String value;
+    private final Map<String, ConfigPayloadBuilder> objectMap;
+    private final Map<String, Array> arrayMap;
+    private final Map<String, MapBuilder> mapBuilderMap;
+    private final ConfigDefinition configDefinition;
+    private List<String> warnings = new ArrayList<>();
+
+    /**
+     * Construct a payload builder that is not a leaf.
+     */
+    public ConfigPayloadBuilder() {
+        this(null, null, null);
+    }
+
+    public ConfigPayloadBuilder(ConfigDefinition configDefinition, List<String> warnings) {
+        this(configDefinition, null, warnings);
+    }
+
+    /**
+     * Construct a payload builder with a leaf value
+     *
+     * @param value The value of this leaf.
+     */
+    private ConfigPayloadBuilder(String value, List<String> warnings) {
+        this(null, value, warnings);
+    }
+
+    private ConfigPayloadBuilder(ConfigDefinition configDefinition, String value, List<String> warnings) {
+        this.objectMap = new LinkedHashMap<>();
+        this.arrayMap = new LinkedHashMap<>();
+        this.mapBuilderMap = new LinkedHashMap<>();
+        this.value = value;
+        this.configDefinition = configDefinition;
+        this.warnings=warnings;
+    }
+
+    /**
+     * Set the value of a config field.
+     *
+     * @param name  Name of the config field.
+     * @param value Value of the config field.
+     */
+    public void setField(String name, String value) {
+        validateField(name, value, warnings);
+        objectMap.put(name, new ConfigPayloadBuilder(value, warnings));
+    }
+
+    private void validateField(String name, String value, List<String> warnings) {
+        if (configDefinition != null) {
+            configDefinition.verify(name, value, warnings);
+        }
+    }
+
+    /**
+     * Get a new payload builder for a config struct, which can be used to add inner values to that struct.
+     *
+     * @param name Name of the struct to create.
+     * @return A payload builder corresponding to the name.
+     */
+    public ConfigPayloadBuilder getObject(String name) {
+        ConfigPayloadBuilder p = objectMap.get(name);
+        if (p == null) {
+            validateObject(name, warnings);
+            p = new ConfigPayloadBuilder(getStructDef(name), warnings);
+            objectMap.put(name, p);
+        }
+        return p;
+    }
+
+    private ConfigDefinition getStructDef(String name) {
+        return (configDefinition == null ? null : configDefinition.getStructDefs().get(name));
+    }
+
+    private void validateObject(String name, List<String> warnings) {
+        if (configDefinition != null) {
+            configDefinition.verify(name, warnings);
+        }
+    }
+
+    /**
+     * Create a new array where new values may be added.
+     *
+     * @param name Name of array.
+     * @return Array object supporting adding elements to it.
+     */
+    public Array getArray(String name) {
+        Array a = arrayMap.get(name);
+        if (a == null) {
+            validateArray(name, warnings);
+            a = new Array(configDefinition, name);
+            arrayMap.put(name, a);
+        }
+        return a;
+    }
+
+    private void validateArray(String name, List<String> warnings) {
+        if (configDefinition != null) {
+            configDefinition.verify(name, warnings);
+        }
+    }
+
+    /**
+     * Create slime tree from this builder.
+     *
+     * @param parent the parent Cursor for this builder
+     */
+    public void resolve(Cursor parent) {
+        // TODO: Fix so that names do not clash
+        for (Map.Entry<String, ConfigPayloadBuilder> entry : objectMap.entrySet()) {
+            String name = entry.getKey();
+            ConfigPayloadBuilder value = entry.getValue();
+            if (value.getValue() == null) {
+                Cursor childCursor = parent.setObject(name);
+                value.resolve(childCursor);
+            } else {
+                // TODO: Support giving correct type
+                parent.setString(name, value.getValue());
+            }
+        }
+        for (Map.Entry<String, ConfigPayloadBuilder.Array> entry : arrayMap.entrySet()) {
+            Cursor array = parent.setArray(entry.getKey());
+            entry.getValue().resolve(array);
+        }
+        for (Map.Entry<String, MapBuilder> entry : mapBuilderMap.entrySet()) {
+            String name = entry.getKey();
+            MapBuilder map = entry.getValue();
+            Cursor cursormap = parent.setObject(name);
+            map.resolve(cursormap);
+        }
+    }
+
+    public ConfigPayloadBuilder override(ConfigPayloadBuilder other) {
+        value = other.value;
+        for (Map.Entry<String, ConfigPayloadBuilder> entry : other.objectMap.entrySet()) {
+            String key = entry.getKey();
+            ConfigPayloadBuilder value = entry.getValue();
+            if (objectMap.containsKey(key)) {
+                objectMap.put(key, objectMap.get(key).override(value));
+            } else {
+                objectMap.put(key, new ConfigPayloadBuilder(value));
+            }
+        }
+        for (Map.Entry<String, Array> entry : other.arrayMap.entrySet()) {
+            String key = entry.getKey();
+            Array value = entry.getValue();
+            if (arrayMap.containsKey(key)) {
+                arrayMap.put(key, arrayMap.get(key).override(value));
+            } else {
+                arrayMap.put(key, new Array(value));
+            }
+        }
+        mapBuilderMap.putAll(other.mapBuilderMap);
+        return this;
+    }
+
+
+    /**
+     * Get the value of this field, if any.
+     *
+     * @return value of field, null if this is not a leaf.
+     */
+    public String getValue() {
+        return value;
+    }
+
+    public void setValue(String value) {
+        this.value = value;
+    }
+
+    /**
+     * Create a new map where new values may be added.
+     *
+     * @param name Name of map.
+     * @return Map builder supporting adding elements to it.
+     */
+    public MapBuilder getMap(String name) {
+        MapBuilder a = mapBuilderMap.get(name);
+        if (a == null) {
+            validateMap(name, warnings);
+            a = new MapBuilder(configDefinition, name);
+            mapBuilderMap.put(name, a);
+        }
+        return a;
+    }
+
+    /**
+     * The definition warnings issued for this payload
+     * @return list of warnings
+     */
+    public List<String> warnings() {
+        return warnings;
+    }
+
+    private void validateMap(String name, List<String> warnings) {
+        if (configDefinition != null) {
+            configDefinition.verify(name, warnings);
+        }
+    }
+
+    public ConfigDefinition getConfigDefinition() {
+        return configDefinition;
+    }
+
+    public class MapBuilder {
+        private final Map<String, ConfigPayloadBuilder> elements = new LinkedHashMap<>();
+        private final ConfigDefinition configDefinition;
+        private final String name;
+        public MapBuilder(ConfigDefinition configDefinition, String name) {
+            this.configDefinition = configDefinition;
+            this.name = name;
+        }
+
+        public void put(String key, String value) {
+            elements.put(key, new ConfigPayloadBuilder(getLeafMapDef(name), value, warnings));
+        }
+
+        public ConfigPayloadBuilder put(String key) {
+            ConfigPayloadBuilder p = new ConfigPayloadBuilder(getStructMapDef(name), warnings);
+            elements.put(key, p);
+            return p;
+        }
+
+        public ConfigPayloadBuilder get(String key) {
+            ConfigPayloadBuilder builder = elements.get(key);
+            if (builder == null) {
+                builder = put(key);
+            }
+            return builder;
+        }
+
+        public void resolve(Cursor parent) {
+            for (Map.Entry<String, ConfigPayloadBuilder> entry : elements.entrySet()) {
+                ConfigPayloadBuilder child = entry.getValue();
+                String childVal = child.getValue();
+                if (childVal != null) {
+                    parent.setString(entry.getKey(), childVal);
+                } else {
+                    Cursor childCursor = parent.setObject(entry.getKey());
+                    child.resolve(childCursor);
+                }
+            }
+        }
+
+        private ConfigDefinition.LeafMapDef getLeafMapDef(String name) {
+            return (configDefinition == null ? null : configDefinition.getLeafMapDefs().get(name));
+        }
+
+        private ConfigDefinition getStructMapDef(String name) {
+            return (configDefinition == null ? null : configDefinition.getStructMapDefs().get(name));
+        }
+
+        public Collection<ConfigPayloadBuilder> getElements() {
+            return elements.values();
+        }
+    }
+
+    /**
+     * Array modes.
+     */
+    private enum ArrayMode {
+        INDEX, APPEND
+    }
+
+    /**
+     * Representation of a config array, which supports both INDEX and APPEND modes.
+     */
+    public class Array {
+        private final Map<Integer, ConfigPayloadBuilder> elements = new LinkedHashMap<>();
+        private ArrayMode mode = ArrayMode.INDEX;
+        private final String name;
+        private final ConfigDefinition configDefinition;
+
+        public Array(ConfigDefinition configDefinition, String name) {
+            this.configDefinition = configDefinition;
+            this.name = name;
+        }
+
+        public Array(Array other) {
+            this.elements.putAll(other.elements);
+            this.mode = other.mode;
+            this.name = other.name;
+            this.configDefinition = other.configDefinition;
+        }
+
+        /**
+         * Append a value to this array.
+         *
+         * @param value Value to append.
+         */
+        public void append(String value) {
+            setAppend();
+            validateArrayElement(getArrayDef(name), value, elements.size());
+            ConfigPayloadBuilder p = new ConfigPayloadBuilder(getArrayDef(name), value, warnings);
+            elements.put(elements.size(), p);
+        }
+
+        private void validateArrayElement(ConfigDefinition.ArrayDef arrayDef, String value, int index) {
+            if (arrayDef != null) {
+                arrayDef.verify(value, index, warnings);
+            }
+        }
+
+        private ConfigDefinition.ArrayDef getArrayDef(String name) {
+            return (configDefinition == null ? null : configDefinition.getArrayDefs().get(name));
+        }
+
+        private ConfigDefinition getInnerArrayDef(String name) {
+            return (configDefinition == null ? null : configDefinition.getInnerArrayDefs().get(name));
+        }
+
+        public Collection<ConfigPayloadBuilder> getElements() {
+            return elements.values();
+        }
+
+        /**
+         * Create a new slime object and returns its payload builder. Append the element after all other elements
+         * in the array.
+         *
+         * @return a payload builder for the new slime object.
+         */
+        public ConfigPayloadBuilder append() {
+            setAppend();
+            ConfigPayloadBuilder p = new ConfigPayloadBuilder(getInnerArrayDef(name), warnings);
+            elements.put(elements.size(), p);
+            return p;
+        }
+
+        /**
+         * Set the value of array element index to value
+         *
+         * @param index Index of array element to set.
+         * @param value Value that the element should point to.
+         */
+        public void set(int index, String value) {
+            verifyIndex();
+            ConfigPayloadBuilder p = new ConfigPayloadBuilder(value, warnings);
+            elements.put(index, p);
+        }
+
+        /**
+         * Set Create a payload object for the given index and return it. Any previously stored version will be
+         * overwritten.
+         *
+         * @param index Index of new element.
+         * @return The payload builder for the newly created slime object.
+         */
+        public ConfigPayloadBuilder set(int index) {
+            verifyIndex();
+            ConfigPayloadBuilder p = new ConfigPayloadBuilder(getInnerArrayDef(name), warnings);
+            elements.put(index, p);
+            return p;
+        }
+
+        /**
+         * Get payload builder in this array corresponding to index. If it does not exist, create a new one.
+         *
+         * @param index of element to get.
+         * @return The corresponding ConfigPayloadBuilder.
+         */
+        public ConfigPayloadBuilder get(int index) {
+            ConfigPayloadBuilder builder = elements.get(index);
+            if (builder == null) {
+                if (mode == ArrayMode.APPEND)
+                    builder = append();
+                else
+                    builder = set(index);
+            }
+            return builder;
+        }
+
+        /**
+         * Try to set append mode, but do some checking if indexed mode has been used first.
+         */
+        private void setAppend() {
+            if (mode == ArrayMode.INDEX && elements.size() > 0) {
+                throw new IllegalStateException("Cannot append elements to an array in index mode with more than one element");
+            }
+            mode = ArrayMode.APPEND;
+        }
+
+        /**
+         * Try and verify that index mode is possible.
+         */
+        private void verifyIndex() {
+            if (mode == ArrayMode.APPEND)
+                throw new IllegalStateException("Cannot reference array elements with index once append is done");
+        }
+
+        public void resolve(Cursor parent) {
+            for (Map.Entry<Integer, ConfigPayloadBuilder> entry : elements.entrySet()) {
+                ConfigPayloadBuilder child = entry.getValue();
+                String childVal = child.getValue();
+                if (childVal != null) {
+                    parent.addString(childVal);
+                } else {
+                    Cursor childCursor = parent.addObject();
+                    child.resolve(childCursor);
+                }
+            }
+        }
+
+        public Array override(Array superior) {
+            if (mode == ArrayMode.INDEX && superior.mode == ArrayMode.INDEX) {
+                elements.putAll(superior.elements);
+            } else {
+                for (ConfigPayloadBuilder builder : superior.elements.values()) {
+                    append().override(builder);
+                }
+            }
+            return this;
+        }
+    }
+
+    private ConfigPayloadBuilder(ConfigPayloadBuilder other) {
+        this.arrayMap = other.arrayMap;
+        this.mapBuilderMap = other.mapBuilderMap;
+        this.value = other.value;
+        this.objectMap = other.objectMap;
+        this.configDefinition = other.configDefinition;
+        this.warnings = other.warnings;
+    }
+
+    public ConfigPayloadBuilder(ConfigPayload payload) {
+        this(new BuilderDecoder(payload.getSlime()).decode(payload.getSlime().get()));
+    }
+
+    private static class BuilderDecoder {
+
+        private final Slime slime;
+        public BuilderDecoder(Slime slime) {
+            this.slime = slime;
+        }
+
+        ConfigPayloadBuilder decode(Inspector element) {
+            ConfigPayloadBuilder root = new ConfigPayloadBuilder();
+            decodeObject(slime, root, element);
+            return root;
+        }
+
+        private static void decodeObject(Slime slime, ConfigPayloadBuilder builder, Inspector element) {
+            BuilderObjectTraverser traverser = new BuilderObjectTraverser(slime, builder);
+            element.traverse(traverser);
+        }
+
+        private static void decode(Slime slime, String name, Inspector inspector, ConfigPayloadBuilder builder) {
+            switch (inspector.type()) {
+                case STRING:
+                    builder.setField(name, inspector.asString());
+                    break;
+                case LONG:
+                    builder.setField(name, String.valueOf(inspector.asLong()));
+                    break;
+                case DOUBLE:
+                    builder.setField(name, String.valueOf(inspector.asDouble()));
+                    break;
+                case BOOL:
+                    builder.setField(name, String.valueOf(inspector.asBool()));
+                    break;
+                case OBJECT:
+                    ConfigPayloadBuilder objectBuilder = builder.getObject(name);
+                    decodeObject(slime, objectBuilder, inspector);
+                    break;
+                case ARRAY:
+                    ConfigPayloadBuilder.Array array = builder.getArray(name);
+                    decodeArray(slime, array, inspector);
+                    break;
+            }
+        }
+
+        private static void decodeArray(Slime slime, Array array, Inspector inspector) {
+            BuilderArrayTraverser traverser = new BuilderArrayTraverser(slime, array);
+            inspector.traverse(traverser);
+        }
+
+        private static class BuilderObjectTraverser implements ObjectTraverser {
+            private final ConfigPayloadBuilder builder;
+            private final Slime slime;
+            public BuilderObjectTraverser(Slime slime, ConfigPayloadBuilder builder) {
+                this.slime = slime;
+                this.builder = builder;
+            }
+
+            @Override
+            public void field(String name, Inspector inspector) {
+                decode(slime, name, inspector, builder);
+            }
+        }
+
+        private static class BuilderArrayTraverser implements ArrayTraverser {
+            private final Array array;
+            private final Slime slime;
+            public BuilderArrayTraverser(Slime slime, Array array) {
+                this.array = array;
+                this.slime = slime;
+            }
+
+            @Override
+            public void entry(int idx, Inspector inspector) {
+                switch (inspector.type()) {
+                    case STRING:
+                        array.append(inspector.asString());
+                        break;
+                    case OBJECT:
+                        decodeObject(slime, array.append(), inspector);
+                        break;
+                }
+            }
+        }
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigTransformer.java b/config/src/main/java/com/yahoo/vespa/config/ConfigTransformer.java
new file mode 100644
index 00000000000..3d15804e14a
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ConfigTransformer.java
@@ -0,0 +1,79 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.FileReference;
+
+import java.nio.file.Path;
+
+import static com.yahoo.vespa.config.ConfigPayloadApplier.IdentityPathAcquirer;
+
+/**
+ * A utility class that can be used to transform config from one format to another.
+ *
+ * @author lulf, musum, tonyv
+ * @since 5.1.6
+ */
+public class ConfigTransformer<T extends ConfigInstance> {
+    /**
+     * Workaround since FileAcquirer is in a separate module that depends on config.
+     * Consider moving FileAcquirer into config instead.
+     */
+    public interface PathAcquirer {
+        Path getPath(FileReference fileReference);
+    }
+
+    private final Class<T> clazz;
+
+    private static volatile PathAcquirer pathAcquirer = new IdentityPathAcquirer();
+
+    /**
+     * For internal use only *
+     */
+    public static void setPathAcquirer(PathAcquirer pathAcquirer) {
+        ConfigTransformer.pathAcquirer = (pathAcquirer == null) ?
+                new IdentityPathAcquirer() :
+                pathAcquirer;
+    }
+
+    /**
+     * Create a transformer capable of converting payloads to clazz
+     *
+     * @param clazz a Class for the config instance which this config payload should create a builder for
+     */
+    public ConfigTransformer(Class<T> clazz) {
+        this.clazz = clazz;
+    }
+
+    /**
+     * Create a ConfigBuilder from a payload, based on the <code>clazz</code> supplied.
+     *
+     * @param payload a Payload to be transformed to builder.
+     * @return a ConfigBuilder
+     */
+    public ConfigInstance.Builder toConfigBuilder(ConfigPayload payload) {
+        ConfigInstance.Builder builder = getRootBuilder();
+        ConfigPayloadApplier<?> creator = new ConfigPayloadApplier<>(builder, pathAcquirer);
+        creator.applyPayload(payload);
+        return builder;
+    }
+
+    private ConfigInstance.Builder getRootBuilder() {
+        ConfigInstance.Builder builder = null;
+        Class<?>[] classes = clazz.getDeclaredClasses();
+        for (Class<?> c : classes) {
+            if (c.getName().endsWith("Builder")) {
+                try {
+                    builder = (ConfigInstance.Builder) c.getConstructor().newInstance();
+                } catch (Exception e) {
+                    throw new RuntimeException("Could not instantiate builder for " + clazz.getName(), e);
+                }
+            }
+        }
+        if (builder == null) {
+            throw new RuntimeException("Could not find builder for " + clazz.getName());
+        } else {
+            return builder;
+        }
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConfigVerification.java b/config/src/main/java/com/yahoo/vespa/config/ConfigVerification.java
new file mode 100644
index 00000000000..eeda2eefdfa
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ConfigVerification.java
@@ -0,0 +1,104 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.slime.ArrayTraverser;
+import com.yahoo.slime.Inspector;
+import com.yahoo.slime.JsonDecoder;
+import com.yahoo.slime.Slime;
+import com.yahoo.text.Utf8;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.InputStream;
+import java.net.URL;
+import java.net.URLConnection;
+import java.util.*;
+
+/**
+ * Tool to verify that configs across multiple config servers are the same.
+ *
+ * @author lulf
+ * @since 5.12
+ */
+public class ConfigVerification {
+    private final static int port = 19071;
+    private final static String prefix = "http://";
+
+    public static void main(String [] args) throws IOException {
+        List<String> configservers = new ArrayList<>();
+        String tenant = "default";
+        String appName = "default";
+        String environment = "prod";
+        String region = "default";
+        String instance= "default";
+        for (String arg : args) {
+            configservers.add(prefix + arg + ":" + port + "/config/v2/tenant/" + tenant + "/application/" + appName + "/environment/" + environment + "/region/" + region + "/instance/" + instance + "/?recursive=true");
+        }
+        System.exit(compareConfigs(listConfigs(configservers)));
+    }
+
+    private static Map<String, Stack<String>> listConfigs(List<String> urls) throws IOException {
+        Map<String, String> outputs = performRequests(urls);
+
+        Map<String, Stack<String>> recurseMappings = new LinkedHashMap<>();
+        for (Map.Entry<String, String> entry : outputs.entrySet()) {
+            Slime slime = new JsonDecoder().decode(new Slime(), Utf8.toBytes(entry.getValue()));
+            final List<String> list = new ArrayList<>();
+            slime.get().field("configs").traverse(new ArrayTraverser() {
+                @Override
+                public void entry(int idx, Inspector inspector) {
+                    list.add(inspector.asString());
+                }
+            });
+            Stack<String> stack = new Stack<>();
+            Collections.sort(list);
+            stack.addAll(list);
+            recurseMappings.put(entry.getKey(), stack);
+        }
+        return recurseMappings;
+    }
+
+    private static Map<String, String> performRequests(List<String> urls) throws IOException {
+        Map<String, String> outputs = new LinkedHashMap<>();
+        for (String url : urls) {
+            outputs.put(url, performRequest(url));
+        }
+        return outputs;
+    }
+
+    private static int compareConfigs(Map<String, Stack<String>> mappings) throws IOException {
+        for (int n = 0; n < mappings.values().iterator().next().size(); n++) {
+            List<String> recurseUrls = new ArrayList<>();
+            for (Map.Entry<String, Stack<String>> entry : mappings.entrySet()) {
+                recurseUrls.add(entry.getValue().pop());
+            }
+            int ret = compareOutputs(performRequests(recurseUrls));
+            if (ret != 0) {
+                return ret;
+            }
+        }
+        return 0;
+    }
+
+    private static int compareOutputs(Map<String, String> outputs) {
+        Map.Entry<String, String> firstEntry = outputs.entrySet().iterator().next();
+        for (Map.Entry<String, String> entry : outputs.entrySet()) {
+            if (!entry.getValue().equals(firstEntry.getValue())) {
+                System.out.println("output from '" + entry.getKey() + "' did not equal output from '" + firstEntry.getKey() + "'");
+                return -1;
+            }
+        }
+        return 0;
+    }
+
+    private static String performRequest(String url) throws IOException {
+        URLConnection connection = new URL(url).openConnection();
+        InputStream response = connection.getInputStream();
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        int ch;
+        while ((ch = response.read()) > -1) {
+            baos.write(ch);
+        }
+        return Utf8.toString(baos.toByteArray());
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/Connection.java b/config/src/main/java/com/yahoo/vespa/config/Connection.java
new file mode 100644
index 00000000000..5ba9f2b598b
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/Connection.java
@@ -0,0 +1,19 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.jrt.Request;
+import com.yahoo.jrt.RequestWaiter;
+
+/**
+ * @author musum
+ */
+public interface Connection {
+
+    void invokeAsync(Request request, double jrtTimeout, RequestWaiter requestWaiter);
+
+    void setError(int errorCode);
+
+    void setSuccess();
+
+    String getAddress();
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ConnectionPool.java b/config/src/main/java/com/yahoo/vespa/config/ConnectionPool.java
new file mode 100644
index 00000000000..db21acc3d6e
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ConnectionPool.java
@@ -0,0 +1,18 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+/**
+ * @author musum
+ */
+public interface ConnectionPool {
+
+    void close();
+
+    void setError(Connection connection, int i);
+
+    Connection getCurrent();
+
+    Connection setNewCurrentConnection();
+
+    int getSize();
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/DefaultValueApplier.java b/config/src/main/java/com/yahoo/vespa/config/DefaultValueApplier.java
new file mode 100644
index 00000000000..187a0f0199b
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/DefaultValueApplier.java
@@ -0,0 +1,84 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.codegen.CNode;
+import com.yahoo.config.codegen.InnerCNode;
+import com.yahoo.config.codegen.LeafCNode;
+import com.yahoo.slime.*;
+
+/**
+ * Applies default values of a given config definition to a slime payload.
+ * TODO: Support giving correct type of default values
+ *
+ * @author lulf
+ * @since 5.1
+ */
+public class DefaultValueApplier {
+
+    public Slime applyDefaults(Slime slime, InnerCNode def) {
+        applyDefaultsRecursive(slime.get(), def);
+        return slime;
+    }
+
+    private void applyDefaultsRecursive(Cursor cursor, InnerCNode def) {
+        if (def.isArray) {
+            applyDefaultsToArray(cursor, def);
+        } else if (def.isMap) {
+            applyDefaultsToMap(cursor, def);
+        } else {
+            applyDefaultsToObject(cursor, def);
+        }
+    }
+
+    private void applyDefaultsToMap(final Cursor cursor, final InnerCNode def) {
+        cursor.traverse(new ObjectTraverser() {
+            @Override
+            public void field(String name, Inspector inspector) {
+                applyDefaultsToObject(cursor.field(name), def);
+            }
+        });
+    }
+
+    private void applyDefaultsToArray(final Cursor cursor, final InnerCNode def) {
+        cursor.traverse(new ArrayTraverser() {
+            @Override
+            public void entry(int idx, Inspector inspector) {
+                applyDefaultsToObject(cursor.entry(idx), def);
+            }
+        });
+    }
+
+    private void applyDefaultsToObject(Cursor cursor, InnerCNode def) {
+        for (CNode child : def.getChildren()) {
+            Cursor childCursor = cursor.field(child.getName());
+            if (isLeafNode(child) && canApplyDefault(childCursor, child)) {
+                applyDefaultToLeaf(cursor, child);
+            } else if (isInnerNode(child)) {
+                if (!childCursor.valid()) {
+                    if (child.isArray) {
+                        childCursor = cursor.setArray(child.getName());
+                    } else {
+                        childCursor = cursor.setObject(child.getName());
+                    }
+                }
+                applyDefaultsRecursive(childCursor, (InnerCNode) child);
+            }
+        }
+    }
+
+    private boolean isInnerNode(CNode child) {
+        return child instanceof InnerCNode;
+    }
+
+    private boolean isLeafNode(CNode child) {
+        return child instanceof LeafCNode;
+    }
+
+    private void applyDefaultToLeaf(Cursor cursor, CNode child) {
+        cursor.setString(child.getName(), ((LeafCNode) child).getDefaultValue().getValue());
+    }
+
+    private boolean canApplyDefault(Cursor cursor, CNode child) {
+        return !cursor.valid() && ((LeafCNode) child).getDefaultValue() != null;
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ErrorCode.java b/config/src/main/java/com/yahoo/vespa/config/ErrorCode.java
new file mode 100644
index 00000000000..50fbe2170a2
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ErrorCode.java
@@ -0,0 +1,66 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+/**
+ * @author <a href="musum@yahoo-inc.com">Harald Musum</a>
+ */
+public final class ErrorCode {
+    // Cannot find a config with this name, version and config md5sum
+    public static final int UNKNOWN_CONFIG = 100000;
+     // No config def with that name or version number
+    public static final int UNKNOWN_DEFINITION = UNKNOWN_CONFIG + 1;
+    public static final int UNKNOWN_DEF_MD5 = UNKNOWN_CONFIG + 4;
+    public static final int UNKNOWN_VESPA_VERSION = UNKNOWN_CONFIG + 5;
+
+    public static final int ILLEGAL_NAME = UNKNOWN_CONFIG + 100;
+    // Version is not a number
+    public static final int ILLEGAL_VERSION = UNKNOWN_CONFIG + 101;
+    public static final int ILLEGAL_CONFIGID = UNKNOWN_CONFIG + 102;
+    public static final int ILLEGAL_DEF_MD5 = UNKNOWN_CONFIG + 103;
+    public static final int ILLEGAL_CONFIG_MD5 = UNKNOWN_CONFIG + 104;
+    // I don't think this will actually happen ...
+    public static final int ILLEGAL_TIMEOUT = UNKNOWN_CONFIG + 105;
+    public static final int ILLEGAL_GENERATION = UNKNOWN_CONFIG + 106;
+    public static final int ILLEGAL_SUB_FLAG = UNKNOWN_CONFIG + 107;
+    public static final int ILLEGAL_NAME_SPACE = UNKNOWN_CONFIG + 108;
+    public static final int ILLEGAL_PROTOCOL_VERSION = UNKNOWN_CONFIG + 109;
+    public static final int ILLEGAL_CLIENT_HOSTNAME = UNKNOWN_CONFIG + 110;
+
+    // hasUpdatedConfig() is true, but generation says the config is older than previous config.
+    public static final int OUTDATED_CONFIG = UNKNOWN_CONFIG + 150;
+
+    public static final int INTERNAL_ERROR = UNKNOWN_CONFIG + 200;
+
+    public static final int APPLICATION_NOT_LOADED = UNKNOWN_CONFIG + 300;
+
+    public static final int INCONSISTENT_CONFIG_MD5 = UNKNOWN_CONFIG + 400;
+
+    private ErrorCode() {
+    }
+
+    public static String getName(int error) {
+        switch(error) {
+            case UNKNOWN_CONFIG:            return "UNKNOWN_CONFIG";
+            case UNKNOWN_DEFINITION:        return "UNKNOWN_DEFINITION";
+            case UNKNOWN_DEF_MD5:           return "UNKNOWN_DEF_MD5";
+            case ILLEGAL_NAME:              return "ILLEGAL_NAME";
+            case ILLEGAL_VERSION:           return "ILLEGAL_VERSION";
+            case ILLEGAL_CONFIGID:          return "ILLEGAL_CONFIGID";
+            case ILLEGAL_DEF_MD5:           return "ILLEGAL_DEF_MD5";
+            case ILLEGAL_CONFIG_MD5:        return "ILLEGAL_CONFIG_MD5";
+            case ILLEGAL_TIMEOUT:           return "ILLEGAL_TIMEOUT";
+            case ILLEGAL_GENERATION:        return "ILLEGAL_GENERATION";
+            case ILLEGAL_SUB_FLAG:          return "ILLEGAL_SUBSCRIBE_FLAG";
+            case ILLEGAL_NAME_SPACE:        return "ILLEGAL_NAME_SPACE";
+            case ILLEGAL_CLIENT_HOSTNAME:   return "ILLEGAL_CLIENT_HOSTNAME";
+            case OUTDATED_CONFIG:           return "OUTDATED_CONFIG";
+            case INTERNAL_ERROR:            return "INTERNAL_ERROR";
+            case APPLICATION_NOT_LOADED:    return "APPLICATION_NOT_LOADED";
+            case ILLEGAL_PROTOCOL_VERSION:  return "ILLEGAL_PROTOCOL_VERSION";
+            case INCONSISTENT_CONFIG_MD5:   return "INCONSISTENT_CONFIG_MD5";
+            case UNKNOWN_VESPA_VERSION:     return "UNKNOWN_VESPA_VERSION";
+            default:                        return "Unknown error";
+        }
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/ErrorType.java b/config/src/main/java/com/yahoo/vespa/config/ErrorType.java
new file mode 100644
index 00000000000..1371f0e93cc
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/ErrorType.java
@@ -0,0 +1,35 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+/**
+ * @author musum
+ */
+public enum ErrorType {
+    TRANSIENT, FATAL;
+
+    public static ErrorType getErrorType(int errorCode) {
+        switch (errorCode) {
+            case com.yahoo.jrt.ErrorCode.CONNECTION:
+            case com.yahoo.jrt.ErrorCode.TIMEOUT:
+                return ErrorType.TRANSIENT;
+            case ErrorCode.UNKNOWN_CONFIG:
+            case ErrorCode.UNKNOWN_DEFINITION:
+            case ErrorCode.UNKNOWN_DEF_MD5:
+            case ErrorCode.ILLEGAL_NAME:
+            case ErrorCode.ILLEGAL_VERSION:
+            case ErrorCode.ILLEGAL_CONFIGID:
+            case ErrorCode.ILLEGAL_DEF_MD5:
+            case ErrorCode.ILLEGAL_CONFIG_MD5:
+            case ErrorCode.ILLEGAL_TIMEOUT:
+            case ErrorCode.OUTDATED_CONFIG:
+            case ErrorCode.INTERNAL_ERROR:
+            case ErrorCode.APPLICATION_NOT_LOADED:
+            case ErrorCode.UNKNOWN_VESPA_VERSION:
+            case ErrorCode.ILLEGAL_PROTOCOL_VERSION:
+            case ErrorCode.INCONSISTENT_CONFIG_MD5:
+                return ErrorType.FATAL;
+            default:
+                return ErrorType.FATAL;
+        }
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/GenerationCounter.java b/config/src/main/java/com/yahoo/vespa/config/GenerationCounter.java
new file mode 100644
index 00000000000..904c1d29818
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/GenerationCounter.java
@@ -0,0 +1,22 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+/**
+ * Interface for counters.
+ *
+ * @author lulf
+ * @since 5.9
+ */
+public interface GenerationCounter {
+    /**
+     * Increment counter and return new value.
+     *
+     * @return incremented counter value.
+     */
+    public long increment();
+
+    /**
+     * @return current counter value.
+     */
+    public long get();
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/GenericConfig.java b/config/src/main/java/com/yahoo/vespa/config/GenericConfig.java
new file mode 100644
index 00000000000..549a51383b1
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/GenericConfig.java
@@ -0,0 +1,52 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.ConfigBuilder;
+import com.yahoo.config.ConfigInstance;
+
+/**
+ *
+ /**
+ * A generic config with an internal generic builder that mimics a real config builder in order to support builders
+ * when we don't have the schema.
+ *
+ * @author lulf
+ * @since 5.1
+ */
+public class GenericConfig {
+    public static class GenericConfigBuilder implements ConfigInstance.Builder {
+        private final ConfigPayloadBuilder payloadBuilder;
+        private final ConfigDefinitionKey defKey;
+        public GenericConfigBuilder(ConfigDefinitionKey defKey, ConfigPayloadBuilder payloadBuilder) {
+            this.defKey = defKey;
+            this.payloadBuilder = payloadBuilder;
+        }
+        private ConfigBuilder override(GenericConfigBuilder superior) {
+            ConfigPayloadBuilder superiorPayload = superior.payloadBuilder;
+            payloadBuilder.override(superiorPayload);
+            return this;
+        }
+
+        public ConfigPayload getPayload() { return ConfigPayload.fromBuilder(payloadBuilder); }
+
+        @Override
+        public boolean dispatchGetConfig(ConfigInstance.Producer producer) {
+            return false;
+        }
+
+        @Override
+        public String getDefName() {
+            return defKey.getName();
+        }
+
+        @Override
+        public String getDefNamespace() {
+            return defKey.getNamespace();
+        }
+
+        @Override
+        public String getDefMd5() {
+            return "";
+        }
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/GetConfigRequest.java b/config/src/main/java/com/yahoo/vespa/config/GetConfigRequest.java
new file mode 100644
index 00000000000..2a12a659538
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/GetConfigRequest.java
@@ -0,0 +1,39 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.vespa.config.protocol.DefContent;
+
+import java.util.Optional;
+
+/**
+ * Interface for getConfig requests.
+ * @author lulf
+ * @since 5.3
+ */
+
+public interface GetConfigRequest {
+
+    /**
+     * Returns the ConfigKey for this request.
+     *
+     * @return the ConfigKey for this config request
+     */
+    public ConfigKey<?> getConfigKey();
+
+    /**
+     * The def file contents in the request, or empty array if not sent/not supported
+     * @return the contents (payload) of the def schema
+     */
+    public DefContent getDefContent();
+
+    /**
+     * Get Vespa version for this GetConfigRequest
+     */
+    public Optional<com.yahoo.vespa.config.protocol.VespaVersion> getVespaVersion();
+
+    /**
+     * Whether or not the config can be retrieved from or stored in a cache.
+     * @return true if content should _not_ be cached, false if it should.
+     */
+    public boolean noCache();
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/JRTConnection.java b/config/src/main/java/com/yahoo/vespa/config/JRTConnection.java
new file mode 100644
index 00000000000..2ddb810981d
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/JRTConnection.java
@@ -0,0 +1,97 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.jrt.*;
+
+import java.text.SimpleDateFormat;
+import java.util.TimeZone;
+import java.util.logging.Logger;
+
+/**
+ * A JRT connection to a config server or config proxy.
+ *
+ * @author <a href="mailto:gunnarga@yahoo-inc.com">Gunnar Gauslaa Bergem</a>
+ */
+public class JRTConnection implements Connection {
+
+    private final String address;
+    private final Supervisor supervisor;
+    private Target target;
+
+    private long lastConnectionAttempt = 0;  // Timestamp for last connection attempt
+    private long lastSuccess = 0;
+    private long lastFailure = 0;
+
+    private static final long delayBetweenConnectionMessage = 30000; //ms
+
+    private static SimpleDateFormat yyyyMMddz;
+    static {
+        yyyyMMddz = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss z");
+        yyyyMMddz.setTimeZone(TimeZone.getTimeZone("GMT"));
+    }
+
+    @Override
+    public void invokeAsync(Request request, double jrtTimeout, RequestWaiter requestWaiter) {
+        getTarget().invokeAsync(request, jrtTimeout, requestWaiter);
+    }
+
+    public final static Logger logger = Logger.getLogger(JRTConnection.class.getPackage().getName());
+
+
+    public JRTConnection(String address, Supervisor supervisor) {
+        this.address = address;
+        this.supervisor = supervisor;
+    }
+
+    public String getAddress() {
+        return address;
+    }
+
+    /**
+     * This is synchronized to avoid multiple ConfigInstances creating new targets simultaneously, if
+     * the existing target is null, invalid or has not yet been initialized.
+     *
+     * @return The existing target, or a new one if invalid or null.
+     */
+    public synchronized Target getTarget() {
+        if (target == null || !target.isValid()) {
+            if ((System.currentTimeMillis() - lastConnectionAttempt) > delayBetweenConnectionMessage) {
+                logger.fine("Connecting to " + address);
+            }
+            lastConnectionAttempt = System.currentTimeMillis();
+            target = supervisor.connect(new Spec(address));
+        }
+        return target;
+    }
+
+    @Override
+    public synchronized void setError(int errorCode) {
+        lastFailure = System.currentTimeMillis();
+    }
+
+    @Override
+    public synchronized void setSuccess() {
+        lastSuccess = System.currentTimeMillis();
+    }
+
+    public void setLastSuccess() {
+        lastSuccess = System.currentTimeMillis();
+    }
+
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append("Address: ");
+        sb.append(address);
+        if (lastSuccess > 0) {
+            sb.append("\n");
+            sb.append("Last success: ");
+            sb.append(yyyyMMddz.format(lastSuccess));
+        }
+        if (lastFailure > 0) {
+            sb.append("\n");
+            sb.append("Last failure: ");
+            sb.append(yyyyMMddz.format(lastFailure));
+        }
+        return sb.toString();
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/JRTConnectionPool.java b/config/src/main/java/com/yahoo/vespa/config/JRTConnectionPool.java
new file mode 100644
index 00000000000..5e52dfc5e2d
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/JRTConnectionPool.java
@@ -0,0 +1,153 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.subscription.ConfigSourceSet;
+import com.yahoo.jrt.Supervisor;
+import com.yahoo.jrt.Transport;
+import com.yahoo.log.LogLevel;
+
+import java.util.ArrayList;
+import java.util.LinkedHashMap;
+import java.util.List;
+import java.util.Map;
+import java.util.concurrent.ThreadLocalRandom;
+import java.util.logging.Logger;
+
+/**
+ * A pool of JRT connections to a config source (either a config server or a config proxy).
+ * The current connection is chosen randomly when calling {#link #setNewCurrentConnection}
+ * (since the connection is chosen randomly, it might end up using the same connection again,
+ * and it will always do so if there is only one source).
+ * The current connection is available with {@link #getCurrent()}.
+ * When calling {@link #setError(Connection, int)}, {#link #setNewCurrentConnection} will always be called.
+ *
+ * @author <a href="mailto:gunnarga@yahoo-inc.com">Gunnar Gauslaa Bergem</a>
+ * @author musum
+ */
+public class JRTConnectionPool implements ConnectionPool {
+    private static final Logger log = Logger.getLogger(JRTConnectionPool.class.getName());
+
+    private final Supervisor supervisor = new Supervisor(new Transport());
+    private final Map<String, JRTConnection> connections = new LinkedHashMap<>();
+
+    // The config sources used by this connection pool.
+    private ConfigSourceSet sourceSet = null;
+
+    // The current connection used by this connection pool.
+    private volatile JRTConnection currentConnection;
+
+    public JRTConnectionPool(ConfigSourceSet sourceSet) {
+        addSources(sourceSet);
+    }
+
+    public JRTConnectionPool(List<String> addresses) {
+        this(new ConfigSourceSet(addresses));
+    }
+
+    public void addSources(ConfigSourceSet sourceSet) {
+        this.sourceSet = sourceSet;
+        synchronized (connections) {
+            for (String address : sourceSet.getSources()) {
+                connections.put(address, new JRTConnection(address, supervisor));
+            }
+        }
+        setNewCurrentConnection();
+    }
+
+    /**
+     * Returns the current JRTConnection instance
+     *
+     * @return a JRTConnection
+     */
+    public synchronized JRTConnection getCurrent() {
+        return currentConnection;
+    }
+
+    /**
+     * Returns and set the current JRTConnection instance by randomly choosing
+     * from the available sources (this means that you might end up using
+     * the same connection).
+     *
+     * @return a JRTConnection
+     */
+    public synchronized JRTConnection setNewCurrentConnection() {
+        List<JRTConnection> sources = getSources();
+        currentConnection = sources.get(ThreadLocalRandom.current().nextInt(0, sources.size()));
+        if (log.isLoggable(LogLevel.DEBUG)) {
+            log.log(LogLevel.DEBUG, "Choosing new connection: " + currentConnection);
+        }
+        return currentConnection;
+    }
+
+    List<JRTConnection> getSources() {
+        List<JRTConnection> ret = new ArrayList<>();
+        synchronized (connections) {
+            for (JRTConnection source : connections.values()) {
+                ret.add(source);
+            }
+        }
+        return ret;
+    }
+
+    ConfigSourceSet getSourceSet() {
+        return sourceSet;
+    }
+
+    @Override
+    public void setError(Connection connection, int errorCode) {
+        connection.setError(errorCode);
+        setNewCurrentConnection();
+    }
+
+    public JRTConnectionPool updateSources(List<String> addresses) {
+        ConfigSourceSet newSources = new ConfigSourceSet(addresses);
+        return updateSources(newSources);
+    }
+
+    public JRTConnectionPool updateSources(ConfigSourceSet sourceSet) {
+        synchronized (connections) {
+            for (JRTConnection conn : connections.values()) {
+                conn.getTarget().close();
+            }
+            connections.clear();
+            addSources(sourceSet);
+        }
+        return this;
+    }
+
+    public String getAllSourceAddresses() {
+        StringBuilder sb = new StringBuilder();
+        synchronized (connections) {
+            for (JRTConnection conn : connections.values()) {
+                sb.append(conn.getAddress());
+                sb.append(",");
+            }
+        }
+        // Remove trailing ","
+        sb.deleteCharAt(sb.length() - 1);
+        return sb.toString();
+    }
+
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        synchronized (connections) {
+            for (JRTConnection conn : connections.values()) {
+                sb.append(conn.toString());
+                sb.append("\n");
+            }
+        }
+        return sb.toString();
+    }
+
+    public void close() {
+        supervisor.transport().shutdown().join();
+    }
+
+    @Override
+    public int getSize() {
+        synchronized (connections) {
+            return connections.size();
+        }
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/JRTMethods.java b/config/src/main/java/com/yahoo/vespa/config/JRTMethods.java
new file mode 100644
index 00000000000..22c57413bc1
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/JRTMethods.java
@@ -0,0 +1,114 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.jrt.Method;
+import com.yahoo.jrt.Request;
+
+/**
+ * Defines methods used for RPC config requests.
+ */
+public class JRTMethods {
+
+    static final String getConfigMethodName = "getConfig";
+    private static final String getConfigRequestTypes = "sssssll";
+    static final String getConfigResponseTypes = "sssssilS";
+
+    static final String configV1getConfigMethodName = "config.v1.getConfig";
+    private static final String configV1GetConfigRequestTypes = "sssssllsSi";
+    static final String configV1GetConfigResponseTypes = "sssssilSs";
+
+    /**
+     * Creates a Method object for the RPC method getConfig.
+     *
+     * @param handler       the object that will handle the method call
+     * @param handlerMethod the method belonging to the handler that will handle the method call
+     * @return a Method
+     */
+    public static Method createGetConfigMethod(Object handler, String handlerMethod) {
+        return new Method(getConfigMethodName, getConfigRequestTypes, getConfigResponseTypes,
+                handler, handlerMethod)
+                .methodDesc("get config")
+                .paramDesc(0, "defName", "config class definition name")
+                .paramDesc(1, "defVersion", "config class definition version")
+                .paramDesc(2, "defMD5", "md5sum for config class definition")
+                .paramDesc(3, "configid", "config id")
+                .paramDesc(4, "configMD5", "md5sum for last got config, empty string if unknown")
+                .paramDesc(5, "timestamp",
+                        "timestamp for last got config, only relevant to the server if useTimestamp != 0")
+                .paramDesc(6, "timeout", "timeout (milliseconds) before answering request if config is unchanged")
+                .returnDesc(0, "defName", "config name")
+                .returnDesc(1, "defVersion", "config version")
+                .returnDesc(2, "defMD5", "md5sum for config class definition")
+                .returnDesc(3, "configid", "requested config id")
+                .returnDesc(4, "configMD5", "md5sum for this config")
+                .returnDesc(5, "changed", "changed flag (1 if config changed, 0 otherwise")
+                .returnDesc(6, "timestamp", "timestamp when config was last changed")
+                .returnDesc(7, "payload", "config payload for the requested config");
+    }
+
+    /**
+     * Creates a Method object for the RPC method config.v1.getConfig. Use both for
+     * getting config and subscribing to config
+     *
+     * @param handler       the object that will handle the method call
+     * @param handlerMethod the method belonging to the handler that will handle the method call
+     * @return a Method
+     */
+    public static Method createConfigV1GetConfigMethod(Object handler, String handlerMethod) {
+        return new Method(configV1getConfigMethodName, configV1GetConfigRequestTypes, configV1GetConfigResponseTypes,
+                handler, handlerMethod)
+                .methodDesc("get config v1")
+                .paramDesc(0, "defName", "config class definition name")
+                .paramDesc(1, "defVersion", "config class definition version")
+                .paramDesc(2, "defMD5", "md5sum for config class definition")
+                .paramDesc(3, "configid", "config id")
+                .paramDesc(4, "configMD5", "md5sum for last got config, empty string if unknown")
+                .paramDesc(5, "generation",
+                        "generation for last got config, only relevant to the server if generation != 0")
+                .paramDesc(6, "timeout", "timeout (milliseconds) before answering request if config is unchanged")
+                .paramDesc(7, "namespace", "namespace for defName")
+                .paramDesc(8, "defContent", "config definition content")
+                .paramDesc(9, "subscribe", "subscribe to config (1) or not (0)")
+                .returnDesc(0, "defName", "config name")
+                .returnDesc(1, "defVersion", "config version")
+                .returnDesc(2, "defMD5", "md5sum for config class definition")
+                .returnDesc(3, "configid", "requested config id")
+                .returnDesc(4, "configMD5", "md5sum for this config")
+                .returnDesc(5, "changed", "changed flag (1 if config changed, 0 otherwise") // TODO Maybe remove?
+                .returnDesc(6, "generation", "generation of config")
+                .returnDesc(7, "payload", "config payload for the requested config")
+                .returnDesc(8, "namespace", "namespace for defName");
+    }
+
+    public static final String configV2getConfigMethodName = "config.v2.getConfig";
+    private static final String configV2GetConfigRequestTypes = "s";
+    private static final String configV2GetConfigResponseTypes = "s";
+    public static Method createConfigV2GetConfigMethod(Object handler, String handlerMethod) {
+        return new Method(configV2getConfigMethodName, configV2GetConfigRequestTypes, configV2GetConfigResponseTypes,
+                handler, handlerMethod)
+                .methodDesc("get config v2")
+                .paramDesc(0, "request", "config request")
+                .returnDesc(0, "response", "config response");
+    }
+
+    public static boolean checkV2ReturnTypes(Request request) {
+        return request.checkReturnTypes(JRTMethods.configV2GetConfigResponseTypes);
+    }
+
+    public static final String configV3getConfigMethodName = "config.v3.getConfig";
+    private static final String configV3GetConfigRequestTypes = "s";
+    private static final String configV3GetConfigResponseTypes = "sx";
+    public static Method createConfigV3GetConfigMethod(Object handler, String handlerMethod) {
+        return new Method(configV3getConfigMethodName, configV3GetConfigRequestTypes, configV3GetConfigResponseTypes,
+                handler, handlerMethod)
+                .methodDesc("get config v3")
+                .paramDesc(0, "request", "config request")
+                .returnDesc(0, "response", "config response")
+                .returnDesc(1, "payload", "config response payload");
+
+    }
+
+    public static boolean checkV3ReturnTypes(Request request) {
+        return request.checkReturnTypes(JRTMethods.configV3GetConfigResponseTypes);
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/LZ4PayloadCompressor.java b/config/src/main/java/com/yahoo/vespa/config/LZ4PayloadCompressor.java
new file mode 100644
index 00000000000..4c51afa3afe
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/LZ4PayloadCompressor.java
@@ -0,0 +1,39 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.vespa.config.util.ConfigUtils;
+import net.jpountz.lz4.LZ4Compressor;
+import net.jpountz.lz4.LZ4Factory;
+
+/**
+ * Wrapper for LZ4 compression that selects compression level based on properties.
+ *
+ * @author lulf
+ * @since 5.19
+ */
+public class LZ4PayloadCompressor {
+    private static final LZ4Factory lz4Factory = LZ4Factory.safeInstance();
+    private static final String VESPA_CONFIG_PROTOCOL_COMPRESSION_LEVEL = "VESPA_CONFIG_PROTOCOL_COMPRESSION_LEVEL";
+    private static final int compressionLevel = getCompressionLevel();
+
+    private static int getCompressionLevel() {
+        return Integer.parseInt(ConfigUtils.getEnvValue("0",
+                System.getenv(VESPA_CONFIG_PROTOCOL_COMPRESSION_LEVEL),
+                System.getenv("services__config_protocol_compression_level"),
+                System.getProperty(VESPA_CONFIG_PROTOCOL_COMPRESSION_LEVEL)));
+    }
+
+    public byte[] compress(byte[] input) {
+        return getCompressor().compress(input);
+    }
+
+    public void decompress(byte[] input, byte[] outputbuffer) {
+        if (input.length > 0) {
+            lz4Factory.safeDecompressor().decompress(input, outputbuffer);
+        }
+    }
+
+    private LZ4Compressor getCompressor() {
+        return (compressionLevel < 7) ? lz4Factory.fastCompressor() : lz4Factory.highCompressor();
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/RawConfig.java b/config/src/main/java/com/yahoo/vespa/config/RawConfig.java
new file mode 100755
index 00000000000..a7c4f4bf788
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/RawConfig.java
@@ -0,0 +1,224 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.text.Utf8String;
+import com.yahoo.vespa.config.protocol.CompressionInfo;
+import com.yahoo.vespa.config.protocol.JRTClientConfigRequest;
+import com.yahoo.vespa.config.protocol.JRTConfigRequest;
+import com.yahoo.vespa.config.protocol.JRTServerConfigRequest;
+import com.yahoo.vespa.config.protocol.Payload;
+import com.yahoo.vespa.config.protocol.VespaVersion;
+import com.yahoo.vespa.config.util.ConfigUtils;
+
+import java.util.Collections;
+import java.util.List;
+import java.util.Optional;
+
+/**
+ * Encapsulates config, usually associated with a {@link JRTConfigRequest}. An instance of this class can represent
+ * either a config that is not yet resolved, a successfully resolved config, or an error.
+ *
+ * @author <a href="musum@yahoo-inc.com">Harald Musum</a>
+ */
+public class RawConfig {
+
+    private final ConfigKey<?> key;
+    private final String defMd5;
+    private final List<String> defContent;
+    private final Payload payload;
+    private final int errorCode;
+    private final String configMd5;
+    private final Optional<VespaVersion> vespaVersion;
+    private long generation;
+
+    /**
+     * Constructor for an empty config (not yet resolved).
+     * @param key     The ConfigKey
+     * @param defMd5  The md5 sum of the .def-file.
+     */
+    public RawConfig(ConfigKey<?> key, String defMd5) {
+        this(key, defMd5, null, "", 0L, 0, Collections.<String>emptyList(), Optional.empty());
+    }
+
+    public RawConfig(ConfigKey<?> key, String defMd5, Payload payload, String configMd5, long generation, List<String> defContent, Optional<VespaVersion> vespaVersion) {
+        this(key, defMd5, payload, configMd5, generation, 0, defContent, vespaVersion);
+    }
+
+    /** Copy constructor */
+    public RawConfig(RawConfig rawConfig) {
+        this(rawConfig.key, rawConfig.defMd5, rawConfig.payload, rawConfig.configMd5,
+                rawConfig.generation, rawConfig.errorCode, rawConfig.defContent, rawConfig.getVespaVersion());
+    }
+
+    public RawConfig(ConfigKey<?> key, String defMd5, Payload payload,
+                   String configMd5, long generation, int errorCode, List<String> defContent, Optional<VespaVersion> vespaVersion) {
+        this.key = key;
+        this.defMd5 = ConfigUtils.getDefMd5FromRequest(defMd5, defContent);
+        this.payload = payload;
+        this.configMd5 = configMd5;
+        this.generation = generation;
+        this.errorCode = errorCode;
+        this.defContent = defContent;
+        this.vespaVersion = vespaVersion;
+    }
+
+    /**
+     * Creates a new Config from the given request, with the values in the response parameters.
+     * @param req a {@link JRTClientConfigRequest}
+     */
+    public static RawConfig createFromResponseParameters(JRTClientConfigRequest req) {
+        return new RawConfig(req.getConfigKey(), req.getConfigKey().getMd5(), req.getNewPayload(), req.getNewConfigMd5(),
+                req.getNewGeneration(), 0, req.getDefContent().asList(), req.getVespaVersion());
+    }
+
+    /**
+     * Creates a new Config from the given request, with the values in the response parameters.
+     * @param req a {@link JRTClientConfigRequest}
+     */
+    public static RawConfig createFromServerRequest(JRTServerConfigRequest req) {
+        return new RawConfig(req.getConfigKey(), req.getConfigKey().getMd5() , Payload.from(new Utf8String(""), CompressionInfo.uncompressed()), req.getRequestConfigMd5(),
+                             req.getRequestGeneration(), 0, req.getDefContent().asList(), req.getVespaVersion());
+    }
+
+
+    public ConfigKey<?> getKey() {
+        return key;
+    }
+
+    public String getName() {
+        return key.getName();
+    }
+
+    public String getNamespace() {
+        return key.getNamespace();
+    }
+
+    public String getConfigId() {
+        return key.getConfigId();
+    }
+
+    public String getConfigMd5() {
+        return configMd5;
+    }
+
+    public String getDefMd5() {
+        return defMd5;
+    }
+
+    public long getGeneration() {
+        return generation;
+    }
+
+    public void setGeneration(long generation) {
+        this.generation = generation;
+    }
+
+    public Payload getPayload() {
+        return payload;
+    }
+
+    public int errorCode() {
+        return errorCode;
+    }
+
+    public String getDefNamespace() {
+        return key.getNamespace();
+    }
+
+    public Optional<VespaVersion> getVespaVersion() {
+        return vespaVersion;
+    }
+
+    /**
+     * Returns true if this config is equal to the config (same payload md5) in the given request.
+     *
+     * @param req  The request for which to compare config payload with this config.
+     * @return  true if this config is equal to the config in the given request.
+     */
+    public boolean hasEqualConfig(JRTServerConfigRequest req) {
+        return (getConfigMd5().equals(req.getRequestConfigMd5()));
+    }
+
+    /**
+     * Returns true if this config has a more recent generation than the config in the given request.
+     *
+     * @param req  The request for which to compare generation with this config.
+     * @return true if this config has a more recent generation than the config in the given request.
+     */
+    public boolean hasNewerGeneration(JRTServerConfigRequest req) {
+        return (getGeneration() > req.getRequestGeneration());
+    }
+
+    /**
+     * Convenience method.
+     * @return true if errorCode() returns 0, false otherwise.
+     */
+    public boolean isError() {
+        return (errorCode() != 0);
+    }
+
+    public boolean equals(Object o) {
+        if (o == this) {
+            return true;
+        }
+        if (! (o instanceof RawConfig)) {
+            return false;
+        }
+        RawConfig other = (RawConfig) o;
+        if (! (key.equals(other.key) &&
+                defMd5.equals(other.defMd5) &&
+                (errorCode == other.errorCode)) ) {
+            return false;
+        }
+        // Need to check error codes before isError, since unequal error codes always means unequal requests,
+        // while non-zero and equal error codes means configs are equal.
+        if (isError())
+            return true;
+        if (generation != other.generation)
+            return false;
+        if (configMd5 != null) {
+            return configMd5.equals(other.configMd5);
+        } else {
+            return (other.configMd5 == null);
+        }
+    }
+
+    public int hashCode() {
+        int hash = 17;
+        if (key != null) {
+            hash = 31 * hash + key.hashCode();
+        }
+        if (defMd5 != null) {
+            hash = 31 * hash + defMd5.hashCode();
+        }
+        hash = 31 * hash + errorCode;
+        if (! isError()) {
+            // configMd5 and generation only matter when the RawConfig is not an error.
+            hash = 31 * hash + (int)(generation ^(generation >>>32));
+            if (configMd5 != null) {
+                hash = 31 * hash + configMd5.hashCode();
+            }
+        }
+        return hash;
+    }
+
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append(key.getNamespace()).append(".").append(key.getName());
+        sb.append(",");
+        sb.append(getDefMd5());
+        sb.append(",");
+        sb.append(key.getConfigId());
+        sb.append(",");
+        sb.append(getConfigMd5());
+        sb.append(",");
+        sb.append(getGeneration());
+        sb.append(",");
+        sb.append(getPayload());
+        return sb.toString();
+    }
+
+    public List<String> getDefContent() {
+        return defContent;
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/SlimeUtils.java b/config/src/main/java/com/yahoo/vespa/config/SlimeUtils.java
new file mode 100644
index 00000000000..6a5052b66cf
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/SlimeUtils.java
@@ -0,0 +1,119 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.slime.*;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.util.Optional;
+
+/**
+ * Extra utilities/operations on slime trees that we would like to have as part of slime in the future, but
+ * which resides here until we have a better place to put it.
+ *
+ * @author lulf
+ * @since 5.8
+ */
+public class SlimeUtils {
+    public static void copyObject(Inspector from, final Cursor to) {
+        if (from.type() != Type.OBJECT) {
+            throw new IllegalArgumentException("Cannot copy object: " + from);
+        }
+        from.traverse(new ObjectTraverser() {
+            @Override
+            public void field(String name, Inspector inspector) {
+                setObjectEntry(inspector, name, to);
+            }
+        });
+
+    }
+
+    private static void setObjectEntry(Inspector from, String name, Cursor to) {
+        switch (from.type()) {
+            case NIX:
+                to.setNix(name);
+                break;
+            case BOOL:
+                to.setBool(name, from.asBool());
+                break;
+            case LONG:
+                to.setLong(name, from.asLong());
+                break;
+            case DOUBLE:
+                to.setDouble(name, from.asDouble());
+                break;
+            case STRING:
+                to.setString(name, from.asString());
+                break;
+            case DATA:
+                to.setData(name, from.asData());
+                break;
+            case ARRAY:
+                Cursor array = to.setArray(name);
+                copyArray(from, array);
+                break;
+            case OBJECT:
+                Cursor object = to.setObject(name);
+                copyObject(from, object);
+                break;
+        }
+    }
+
+    private static void copyArray(Inspector from, final Cursor to) {
+        from.traverse(new ArrayTraverser() {
+            @Override
+            public void entry(int i, Inspector inspector) {
+                addValue(inspector, to);
+            }
+        });
+
+    }
+
+    private static void addValue(Inspector from, Cursor to) {
+        switch (from.type()) {
+            case NIX:
+                to.addNix();
+                break;
+            case BOOL:
+                to.addBool(from.asBool());
+                break;
+            case LONG:
+                to.addLong(from.asLong());
+                break;
+            case DOUBLE:
+                to.addDouble(from.asDouble());
+                break;
+            case STRING:
+                to.addString(from.asString());
+                break;
+            case DATA:
+                to.addData(from.asData());
+                break;
+            case ARRAY:
+                Cursor array = to.addArray();
+                copyArray(from, array);
+                break;
+            case OBJECT:
+                Cursor object = to.addObject();
+                copyObject(from, object);
+                break;
+        }
+
+    }
+
+    public static byte[] toJsonBytes(Slime slime) throws IOException {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        new JsonFormat(true).encode(baos, slime);
+        return baos.toByteArray();
+    }
+
+    public static Slime jsonToSlime(byte[] json) {
+        Slime slime = new Slime();
+        new JsonDecoder().decode(slime, json);
+        return slime;
+    }
+
+    public static Optional<String> optionalString(Inspector inspector) {
+        return Optional.of(inspector.asString()).filter(s -> !s.isEmpty());
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/Source.java b/config/src/main/java/com/yahoo/vespa/config/Source.java
new file mode 100644
index 00000000000..3ec17038506
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/Source.java
@@ -0,0 +1,101 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.ConfigurationRuntimeException;
+
+import java.util.logging.Logger;
+
+/**
+ * A general config source that retrieves config for its SourceConfig.
+ *
+ * This class and its subclasses are thread safe.
+ *
+ * Note that it is the responsibility of the user to set a source's state to OPEN and CANCELLED, and
+ * that the READY state can be set by the user as a mark of progress e.g. when waiting for a monitor/lock.
+ * All other states are set by this class or one of its subclasses.
+ *
+ * Originally designed for re-use by closing and reopening, but this caused problems related to
+ * synchronization between this class and ConfigInstance.subscribeLock. Currently (2008-05-08)
+ * a source cannot be reopened once it has been cancelled.
+ *
+ * @author <a href="gv@yahoo-inc.com">G. Voldengen</a>
+ */
+public abstract class Source {
+
+    public enum State { NEW, OPEN_PENDING, READY, OPEN, CANCEL_REQUESTED, CANCELLED }
+
+    protected volatile SourceConfig config;
+    protected volatile State state = State.NEW;
+    protected long openTimestamp = 0;
+    public final static Logger logger = Logger.getLogger(Source.class.getPackage().getName());
+
+    public Source(SourceConfig sourceConfig) {
+        this.config = sourceConfig;
+    }
+
+    /**
+     * Opens this config source.
+     * Typically called when the first subscriber subscribes to our ConfigInstance.
+     */
+    public final synchronized void open() {
+        if ((state == State.OPEN) || (state == State.OPEN_PENDING)) {
+            return;
+        } else if ((state == State.CANCELLED) || (state == State.CANCEL_REQUESTED)) {
+            throw new ConfigurationRuntimeException("Subscription with config ID: " + config.getConfigId() + ": Trying to reopen a cancelled source, should not happen.", null);
+        }
+        state = State.OPEN_PENDING;
+        openTimestamp = System.currentTimeMillis();
+        myOpen();
+        getConfig();
+    }
+
+    /**
+     * Optional subclass hook for the open() method.
+     */
+    protected void myOpen() { }
+
+    /**
+     * Gets config from this config source.
+     */
+    public final synchronized void getConfig() {
+        if ((state == State.CANCELLED) || (state == State.CANCEL_REQUESTED)) {
+            logger.info("Trying to retrieve config from source " + this + " in state: " + state);
+            return;
+        }
+        myGetConfig();
+    }
+
+    /**
+     * Mandatory subclass hook for the getConfig() method.
+     */
+    protected abstract void myGetConfig();
+
+    /**
+     * Cancels this config source. Typically called when our ConfigInstance has no more subscribers.
+     *
+     * Irreversible. Reopening a cancelled source would cause problems with multiple threads accessing the source
+     * simultaneously. With better synchronization mechanisms it _should_ be possible to close and reopen a source.
+     */
+    public final void cancel() {
+        logger.fine("Closing source " + this + " from state " + state);
+        if ((state == State.CANCELLED) || (state == State.CANCEL_REQUESTED)) {
+            return;
+        }
+        state = State.CANCEL_REQUESTED;
+        myCancel();
+    }
+
+    /**
+     * Optional subclass hook for the cancel() method.
+     * Should typically free all the subclass' resources, i.e. requests, threads etc..
+     */
+    protected void myCancel() { }
+
+    public State getState() {
+        return state;
+    }
+
+    public void setState(State state) {
+        this.state = state;
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/SourceConfig.java b/config/src/main/java/com/yahoo/vespa/config/SourceConfig.java
new file mode 100644
index 00000000000..49484e16ff0
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/SourceConfig.java
@@ -0,0 +1,48 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import java.util.List;
+
+/**
+ * Interface for config instances that use a {@link Source} to retrieve config values.
+ *
+ * @author <a href="gv@yahoo-inc.com">Gj\u00F8ran Voldengen</a>
+ */
+public interface SourceConfig {
+
+    /**
+     * Notify subscribers that this config has been initialized by the {@link Source}.
+     */
+    public void notifyInitMonitor();
+
+    /**
+     * Sets the fields in the config object from the payload in the given request and updates subscribers
+     * with the new config. The given request can be an error response with an error code and no payload.
+     *
+     * @param req  Config request containing return values, or an error response.
+     */
+    public void setConfig(com.yahoo.vespa.config.protocol.JRTClientConfigRequest req);
+
+    /**
+     * Sets this config's generation.
+     *
+     * @param generation The new generation (usually from the source).
+     */
+    public void setGeneration(long generation);
+
+    public String getDefName();
+    public String getDefNamespace();
+    public String getDefVersion();
+    public List<String> getDefContent();
+    public String getDefMd5();
+
+    public String getConfigId();
+    public ConfigKey<?> getKey();
+
+    public String getConfigMd5();
+
+    public long getGeneration();
+
+    public RawConfig getConfig();
+
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/TimingValues.java b/config/src/main/java/com/yahoo/vespa/config/TimingValues.java
new file mode 100644
index 00000000000..46f0854084c
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/TimingValues.java
@@ -0,0 +1,262 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import java.util.Random;
+
+/**
+ * Timeouts, delays and retries used in RPC config protocol.
+ *
+ * @author <a href="mailto:gunnarga@yahoo-inc.com">Gunnar Gauslaa Bergem</a>
+ */
+public class TimingValues {
+    public static final long defaultNextConfigTimeout = 1000;
+    // See getters below for an explanation of how these values are used and interpreted
+    // All time values in milliseconds.
+    private long successTimeout = 600000;
+    private long errorTimeout = 20000;
+    private long initialTimeout = 15000;
+    private long subscribeTimeout = 55000;
+    private long configuredErrorTimeout = -1;  // Don't ever timeout (and do not use error response) when we are already configured
+    private long nextConfigTimeout = defaultNextConfigTimeout;
+
+    private long fixedDelay = 5000;
+    private long unconfiguredDelay = 1000;
+    private long configuredErrorDelay = 15000;
+    private int  maxDelayMultiplier = 10;
+    private final Random rand;
+
+    public TimingValues() {
+        this.rand = new Random(System.currentTimeMillis());
+    }
+
+    // TODO Should add nextConfigTimeout in all constructors
+    public TimingValues(long successTimeout,
+                        long errorTimeout,
+                        long initialTimeout,
+                        long subscribeTimeout,
+                        long unconfiguredDelay,
+                        long configuredErrorDelay,
+                        long fixedDelay,
+                        int maxDelayMultiplier) {
+
+        this.successTimeout = successTimeout;
+        this.errorTimeout = errorTimeout;
+        this.initialTimeout = initialTimeout;
+        this.subscribeTimeout = subscribeTimeout;
+        this.unconfiguredDelay = unconfiguredDelay;
+        this.configuredErrorDelay = configuredErrorDelay;
+        this.fixedDelay = fixedDelay;
+        this.maxDelayMultiplier = maxDelayMultiplier;
+        this.rand = new Random(System.currentTimeMillis());
+    }
+
+    private TimingValues(long successTimeout,
+                        long errorTimeout,
+                        long initialTimeout,
+                        long subscribeTimeout,
+                        long unconfiguredDelay,
+                        long configuredErrorDelay,
+                        long fixedDelay,
+                        int maxDelayMultiplier,
+                        Random rand) {
+
+        this.successTimeout = successTimeout;
+        this.errorTimeout = errorTimeout;
+        this.initialTimeout = initialTimeout;
+        this.subscribeTimeout = subscribeTimeout;
+        this.unconfiguredDelay = unconfiguredDelay;
+        this.configuredErrorDelay = configuredErrorDelay;
+        this.fixedDelay = fixedDelay;
+        this.maxDelayMultiplier = maxDelayMultiplier;
+        this.rand = rand;
+    }
+
+    public TimingValues(TimingValues tv) {
+        this(tv.successTimeout,
+                tv.errorTimeout,
+                tv.initialTimeout,
+                tv.subscribeTimeout,
+                tv.unconfiguredDelay,
+                tv.configuredErrorDelay,
+                tv.fixedDelay,
+                tv.maxDelayMultiplier,
+                tv.getRandom());
+    }
+
+    public TimingValues(TimingValues tv, Random random) {
+        this(tv.successTimeout,
+                tv.errorTimeout,
+                tv.initialTimeout,
+                tv.subscribeTimeout,
+                tv.unconfiguredDelay,
+                tv.configuredErrorDelay,
+                tv.fixedDelay,
+                tv.maxDelayMultiplier,
+                random);
+    }
+
+    /**
+     * Returns timeout to use as server timeout when previous config request was a success.
+     *
+     * @return timeout in milliseconds.
+     */
+    public long getSuccessTimeout() {
+        return successTimeout;
+    }
+
+    /**
+     * Returns timeout to use as server timeout when we got an error with the previous config request.
+     *
+     * @return timeout in milliseconds.
+     */
+    public long getErrorTimeout() {
+        return errorTimeout;
+    }
+
+    /**
+     * Returns initial timeout to use as server timeout when a config is requested for the first time.
+     *
+     * @return timeout in milliseconds.
+     */
+    public long getInitialTimeout() {
+        return initialTimeout;
+    }
+
+    public TimingValues setInitialTimeout(long t) {
+        initialTimeout = t;
+        return this;
+    }
+
+    /**
+     * Returns timeout to use as server timeout when subscribing for the first time.
+     *
+     * @return timeout in milliseconds.
+     */
+    public long getSubscribeTimeout() {
+        return subscribeTimeout;
+    }
+
+    public TimingValues setSubscribeTimeout(long t) {
+        subscribeTimeout = t;
+        return this;
+    }
+
+    /**
+     * Returns the time to retry getting config from the remote sources, until the next error response will
+     * be set as config. Counted from the last ok request was received. A negative value means that
+     * we will always retry getting config and never set an error response as config.
+     *
+     * @return timeout in milliseconds.
+     */
+    public long getConfiguredErrorTimeout() {
+        return configuredErrorTimeout;
+    }
+
+    public TimingValues setConfiguredErrorTimeout(long t) {
+        configuredErrorTimeout = t;
+        return this;
+    }
+
+    /**
+     * Returns timeout used when calling {@link com.yahoo.config.subscription.ConfigSubscriber#nextConfig()} or
+     * {@link com.yahoo.config.subscription.ConfigSubscriber#nextGeneration()}
+     *
+     * @return timeout in milliseconds.
+     */
+    public long getNextConfigTimeout() {
+        return nextConfigTimeout;
+    }
+
+    public TimingValues setNextConfigTimeout(long t) {
+        nextConfigTimeout = t;
+        return this;
+    }
+
+    /**
+     * Returns time to wait until next attempt to get config after a failed request when the client has not
+     * gotten a successful response to a config subscription (i.e, the client has not been configured).
+     * A negative value means that there will never be a next attempt. If a negative value is set, the
+     * user must also setSubscribeTimeout(0) to prevent a deadlock while subscribing.
+     *
+     * @return delay in milliseconds, a negative value means never.
+     */
+    public long getUnconfiguredDelay() {
+        return unconfiguredDelay;
+    }
+
+    public TimingValues setUnconfiguredDelay(long d) {
+        unconfiguredDelay = d;
+        return this;
+    }
+
+    /**
+     * Returns time to wait until next attempt to get config after a failed request when the client has
+     * previously gotten a successful response to a config subscription (i.e, the client is configured).
+     * A negative value means that there will never be a next attempt.
+     *
+     * @return delay in milliseconds, a negative value means never.
+     */
+    public long getConfiguredErrorDelay() {
+        return configuredErrorDelay;
+    }
+
+    public TimingValues setConfiguredErrorDelay(long d) {
+        configuredErrorDelay = d;
+        return this;
+    }
+
+    /**
+     * Returns maximum multiplier to use when calculating delay (the delay is multiplied by the number of
+     * failed requests, unless that number is this maximum multiplier).
+     *
+     * @return timeout in milliseconds.
+     */
+    public int getMaxDelayMultiplier() {
+        return maxDelayMultiplier;
+    }
+
+
+    public TimingValues setSuccessTimeout(long successTimeout) {
+        this.successTimeout = successTimeout;
+        return this;
+    }
+
+    /**
+     * Returns fixed delay that is used when retrying getting config no matter if it was a success or an error
+     * and independent of number of retries.
+     *
+     * @return timeout in milliseconds.
+     */
+    public long getFixedDelay() {
+        return fixedDelay;
+    }
+
+    /**
+     * Returns a number +/- a random component
+     *
+     * @param val      input
+     * @param fraction for instance 0.1 for +/- 10%
+     * @return a number
+     */
+    public long getPlusMinusFractionRandom(long val, float fraction) {
+        return Math.round(val - (val * fraction) + (rand.nextFloat() * 2l * val * fraction));
+    }
+
+    Random getRandom() {
+        return rand;
+    }
+
+    @Override
+    public String toString() {
+        return "TimingValues [successTimeout=" + successTimeout
+                + ", errorTimeout=" + errorTimeout + ", initialTimeout="
+                + initialTimeout + ", subscribeTimeout=" + subscribeTimeout
+                + ", configuredErrorTimeout=" + configuredErrorTimeout
+                + ", fixedDelay=" + fixedDelay + ", unconfiguredDelay="
+                + unconfiguredDelay + ", configuredErrorDelay="
+                + configuredErrorDelay + ", maxDelayMultiplier="
+                + maxDelayMultiplier + ", rand=" + rand + "]";
+    }
+
+
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/UnknownConfigIdException.java b/config/src/main/java/com/yahoo/vespa/config/UnknownConfigIdException.java
new file mode 100644
index 00000000000..d78eebe3ed4
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/UnknownConfigIdException.java
@@ -0,0 +1,16 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+/**
+ * Used when a config model does not recognize a config id
+ * @author vegardh
+ *
+ */
+@SuppressWarnings("serial")
+public class UnknownConfigIdException extends IllegalArgumentException {
+
+    public UnknownConfigIdException(String msg) {
+        super(msg);
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/benchmark/LoadTester.java b/config/src/main/java/com/yahoo/vespa/config/benchmark/LoadTester.java
new file mode 100644
index 00000000000..07f2911cc69
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/benchmark/LoadTester.java
@@ -0,0 +1,259 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.benchmark;
+
+import com.yahoo.collections.Tuple2;
+import com.yahoo.io.IOUtils;
+import com.yahoo.jrt.*;
+import com.yahoo.system.CommandLineParser;
+import com.yahoo.text.Utf8;
+import com.yahoo.vespa.config.ConfigDefinitionKey;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.protocol.*;
+import com.yahoo.vespa.config.util.ConfigUtils;
+
+import java.io.*;
+import java.util.*;
+
+/**
+ * A load client for a config server or proxy.
+ *
+ * Log messages from a run will have a # first in the line, the end result will not.
+ *
+ * @author vegardh
+ */
+public class LoadTester {
+
+    private static boolean debug = false;
+    private Transport transport = new Transport();
+    protected Supervisor supervisor = new Supervisor(transport);
+    private List<ConfigKey<?>> configs = new ArrayList<>();
+    private Random random = new Random(System.currentTimeMillis());
+    private Map<ConfigDefinitionKey, Tuple2<String, String[]>> defs = new HashMap<>();
+    private long protocolVersion = Long.parseLong(JRTConfigRequestFactory.getProtocolVersion());
+    private CompressionType compressionType = JRTConfigRequestFactory.getCompressionType();
+
+    /**
+     * @param args command-line arguments
+     */
+    public static void main(String[] args) throws IOException, InterruptedException {
+        CommandLineParser parser = new CommandLineParser("LoadTester", args);
+        parser.addLegalUnarySwitch("-d", "debug");
+        parser.addRequiredBinarySwitch("-c", "host (config proxy or server)");
+        parser.addRequiredBinarySwitch("-p", "port");
+        parser.addRequiredBinarySwitch("-i", "iterations per thread");
+        parser.addRequiredBinarySwitch("-t", "threads");
+        parser.addLegalBinarySwitch("-l", "configs file, on form name,configid. (To get list: configproxy-cmd -m cache | cut -d ',' -f1-2)");
+        parser.addLegalBinarySwitch("-dd", "dir with def files, must be of form name.def");
+        parser.parse();
+        String host = parser.getBinarySwitches().get("-c");
+        int port = Integer.parseInt(parser.getBinarySwitches().get("-p"));
+        int iterations = Integer.parseInt(parser.getBinarySwitches().get("-i"));
+        int threads = Integer.parseInt(parser.getBinarySwitches().get("-t"));
+        String configsList = parser.getBinarySwitches().get("-l");
+        String defPath = parser.getBinarySwitches().get("-dd");
+        debug = parser.getUnarySwitches().contains("-d");
+        LoadTester loadTester = new LoadTester();
+        loadTester.runLoad(host, port, iterations, threads, configsList, defPath);
+    }
+
+    private void runLoad(String host, int port, int iterations, int threads,
+                         String configsList, String defPath) throws IOException, InterruptedException {
+        configs = readConfigs(configsList);
+        defs = readDefs(defPath);
+        List<LoadThread> threadList = new ArrayList<>();
+        long start = System.currentTimeMillis();
+        Metrics m = new Metrics();
+
+        for (int i = 0; i < threads; i++) {
+            LoadThread lt = new LoadThread(iterations, host, port);
+            threadList.add(lt);
+            lt.start();
+        }
+
+        for (LoadThread lt : threadList) {
+            lt.join();
+            m.merge(lt.metrics);
+        }
+        printOutput(start, threads, iterations, m);
+    }
+
+    private Map<ConfigDefinitionKey, Tuple2<String, String[]>> readDefs(String defPath) throws IOException {
+        Map<ConfigDefinitionKey, Tuple2<String, String[]>> ret = new HashMap<>();
+        if (defPath==null) return ret;
+        File defDir = new File(defPath);
+        if (!defDir.isDirectory()) {
+            System.out.println("# Given def file dir is not a directory: "+defDir.getPath()+" , will not send def contents in requests.");
+            return ret;
+        }
+        final File[] files = defDir.listFiles();
+        if (files == null) {
+            System.out.println("# Given def file dir has no files: "+defDir.getPath()+" , will not send def contents in requests.");
+            return ret;
+        }
+        for (File f : files) {
+            String name = f.getName();
+            if (!name.endsWith(".def")) continue;
+            String[] splitted = name.split("\\.");
+            if (splitted.length<2) continue;
+            String nam = splitted[splitted.length - 2];
+            String contents = IOUtils.readFile(f);
+            ConfigDefinitionKey key = ConfigUtils.createConfigDefinitionKeyFromDefContent(nam, Utf8.toBytes(contents));
+            ret.put(key, new Tuple2<>(ConfigUtils.getDefMd5(Arrays.asList(contents.split("\n"))), contents.split("\n")));
+        }
+        System.out.println("#  Read "+ret.size()+" def files from "+defDir.getPath());
+        return ret;
+    }
+
+    private void printOutput(long start, long threads, long iterations, Metrics metrics) {
+        long stop = System.currentTimeMillis();
+        float durSec = (float) (stop - start) / 1000f;
+        StringBuilder sb = new StringBuilder();
+        sb.append("#reqs/sec #bytes/sec #avglatency #minlatency #maxlatency #failedrequests\n");
+        sb.append(((float) (iterations * threads)) / durSec).append(",");
+        sb.append((metrics.totBytes / durSec)).append(",");
+        sb.append((metrics.totLatency / threads / iterations)).append(",");
+        sb.append((metrics.minLatency)).append(",");
+        sb.append((metrics.maxLatency)).append(",");
+        sb.append((metrics.failedRequests));
+        sb.append("\n");
+        System.out.println(sb.toString());
+    }
+
+    private List<ConfigKey<?>> readConfigs(String configsList) throws IOException {
+        List<ConfigKey<?>> ret = new ArrayList<>();
+        BufferedReader br = new BufferedReader(new InputStreamReader(new FileInputStream(configsList), "UTF-8"));
+        String str = br.readLine();
+        while (str != null) {
+            String[] nameAndId = str.split(",");
+            Tuple2<String, String> nameAndNamespace = ConfigUtils.getNameAndNamespaceFromString(nameAndId[0]);
+            ConfigKey<?> key = new ConfigKey<>(nameAndNamespace.first, nameAndId[1], nameAndNamespace.second);
+            ret.add(key);
+            str = br.readLine();
+        }
+        br.close();
+        return ret;
+    }
+
+    private class Metrics {
+        public long totBytes = 0;
+        public long totLatency = 0;
+        public long failedRequests = 0;
+        public long maxLatency = Long.MIN_VALUE;
+        public long minLatency = Long.MAX_VALUE;
+
+        public void merge(Metrics m) {
+            this.totBytes += m.totBytes;
+            this.totLatency += m.totLatency;
+            this.failedRequests += m.failedRequests;
+            updateMin(m.minLatency);
+            updateMax(m.maxLatency);
+        }
+
+
+        public void update(long bytes, long latency) {
+            this.totBytes += bytes;
+            this.totLatency += latency;
+            updateMin(latency);
+            updateMax(latency);
+        }
+
+        private void updateMin(long latency) {
+            if (latency < minLatency)
+                minLatency = latency;
+        }
+
+        private void updateMax(long latency) {
+            if (latency > maxLatency)
+                maxLatency = latency;
+        }
+
+        private void incFailedRequests() {
+            failedRequests++;
+        }
+    }
+
+    private class LoadThread extends Thread {
+        int iterations = 0;
+        String host = "";
+        int port = 0;
+        Metrics metrics = new Metrics();
+
+        public LoadThread(int iterations, String host, int port) {
+            this.iterations = iterations;
+            this.host = host;
+            this.port = port;
+        }
+
+        @Override
+        public void run() {
+            Spec spec = new Spec(host, port);
+            Target target = connect(spec);
+            ConfigKey<?> reqKey;
+            JRTClientConfigRequest request;
+            int totConfs = configs.size();
+            boolean reconnCycle = false; // to log reconn message only once, for instance at restart
+            for (int i = 0; i < iterations; i++) {
+                reqKey = configs.get(random.nextInt(totConfs));
+                ConfigDefinitionKey dKey = new ConfigDefinitionKey(reqKey);
+                Tuple2<String, String[]> defContent = defs.get(dKey);
+                if (defContent==null && defs.size()>0) { // Only complain if we actually did run with a def dir
+                    System.out.println("# No def found for "+dKey+", not sending in request.");
+                }/* else {
+                    System.out.println("# FOUND: "+dKey+" : "+ StringUtilities.implode(defContent, "\n"));
+                }*/
+                request = getRequest(ConfigKey.createFull(reqKey.getName(), reqKey.getConfigId(), reqKey.getNamespace(), defContent.first), defContent.second);
+                if (debug) System.out.println("# Requesting: " + reqKey);
+                long start = System.currentTimeMillis();
+                target.invokeSync(request.getRequest(), 10.0);
+                long end = System.currentTimeMillis();
+                if (request.isError()) {
+                    if ("Connection lost".equals(request.errorMessage()) || "Connection down".equals(request.errorMessage())) {
+                        try {
+                            Thread.sleep(100);
+                        } catch (InterruptedException e) {
+                            throw new RuntimeException(e);
+                        }
+                        if (!reconnCycle) {
+                            System.out.println("# Connection lost, reconnecting...");
+                            reconnCycle = true;
+                        }
+                        target = connect(spec);
+                    } else {
+                        System.err.println(request.errorMessage());
+                    }
+                    metrics.incFailedRequests();
+                } else {
+                    if (reconnCycle) {
+                        reconnCycle = false;
+                        System.out.println("# Connection OK");
+                    }
+                    long duration = end - start;
+
+                    if (debug) {
+                        String payload = request.getNewPayload().toString();
+                        metrics.update(payload.length(), duration); // assume 8 bit...
+                        System.out.println("# Ret: " + payload);
+                    } else {
+                        metrics.update(0, duration);
+                    }
+                }
+            }
+        }
+
+        private JRTClientConfigRequest getRequest(ConfigKey<?> reqKey, String[] defContent) {
+            if (defContent==null) defContent=new String[0];
+            final long serverTimeout = 1000;
+            if (protocolVersion == 3) {
+                return JRTClientConfigRequestV3.createWithParams(reqKey, DefContent.fromList(Arrays.asList(defContent)),
+                                                                 "unknown", "", 0, serverTimeout, Trace.createDummy(),
+                                                                 compressionType, Optional.empty());
+            } else {
+                throw new RuntimeException("Unsupported protocol version" + protocolVersion);
+            }
+        }
+
+        private Target connect(Spec spec) {
+            return supervisor.connectSync(spec);
+        }
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/benchmark/StressTester.java b/config/src/main/java/com/yahoo/vespa/config/benchmark/StressTester.java
new file mode 100644
index 00000000000..3f2cd9ae2fa
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/benchmark/StressTester.java
@@ -0,0 +1,277 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.benchmark;
+
+import com.yahoo.jrt.*;
+import com.yahoo.system.CommandLineParser;
+
+import java.io.*;
+import java.util.*;
+
+/**
+ * /**
+ * A class for stress-testing config server and config proxy.
+ * Includes an RPC server interface for communicating
+ * with test classes that implement the {@link Tester} interface.
+ *
+ * @author <a href="mailto:musum@yahoo-inc.com">Harald Musum</a>
+ * @since 5.1.5
+ */
+public class StressTester {
+    private static boolean debug = false;
+    private final String testClassName;
+    private final List<Thread> threadList = new ArrayList<>();
+    private final List<TestRunner> testRunners = new ArrayList<>();
+
+    public StressTester(String testClass) {
+        this.testClassName = testClass;
+    }
+
+    /**
+     * @param args command-line arguments
+     */
+    public static void main(String[] args) {
+        CommandLineParser parser = new CommandLineParser("StressTester", args);
+        parser.addLegalUnarySwitch("-d", "debug");
+        parser.addRequiredBinarySwitch("-c", "host (config proxy or server)");
+        parser.addRequiredBinarySwitch("-p", "port");
+        parser.addLegalBinarySwitch("-class", "Use class with this name from test bundle (must be given in class path)");
+        parser.addLegalBinarySwitch("-serverport", "port for rpc server");
+        parser.parse();
+        // TODO Handle other hosts and ports
+        String host = parser.getBinarySwitches().get("-c");
+        int port = Integer.parseInt(parser.getBinarySwitches().get("-p"));
+        debug = parser.getUnarySwitches().contains("-d");
+        String classNameInBundle = parser.getBinarySwitches().get("-class");
+        int serverPort = Integer.parseInt(parser.getBinarySwitches().get("-serverport"));
+        RpcServer rpcServer = new RpcServer(null, serverPort, new StressTester(classNameInBundle));
+        new Thread(rpcServer).start();
+    }
+
+    static class TestRunner implements Runnable {
+        private final Tester tester;
+        private volatile boolean stop = false;
+
+        TestRunner(Tester tester) {
+            this.tester = tester;
+        }
+
+        @Override
+        public void run() {
+            tester.subscribe();
+            while (!stop) {
+                tester.fetch();
+            }
+            tester.close();
+        }
+
+        public void stop() {
+            stop = true;
+        }
+    }
+
+    private Map<String, Map<String, String>> getVerificationMap(String verificationFile) {
+        // Read verification file into a map that test stubs should verify against
+        Map<String, Map<String, String>> verificationMap = new HashMap<>();
+        if (verificationFile != null) {
+            BufferedReader reader = null;
+            try {
+                reader = new BufferedReader(new FileReader(verificationFile));
+                String l;
+                while ((l = reader.readLine()) != null) {
+                    String[] line = l.split(",");
+                    String defFile = line[0];
+                    String fieldName = line[1];
+                    String expectedValue = line[2];
+                    Map<String, String> defExpected = verificationMap.get(defFile);
+                    if (defExpected == null)
+                        defExpected = new HashMap<>();
+                    defExpected.put(fieldName, expectedValue);
+                    verificationMap.put(defFile, defExpected);
+                }
+            } catch (Exception e) {
+                throw new IllegalArgumentException("Unable to load verification file " + verificationFile);
+            } finally {
+                if (reader != null) try {
+                    reader.close();
+                } catch (IOException e) {
+                    e.printStackTrace();
+                }
+            }
+        }
+        return verificationMap;
+    }
+
+    private void startTesters(int threads) {
+        // Load and run actual test stub
+        Class<?> testClass;
+        try {
+            testClass = Class.forName(testClassName);
+            threadList.clear();
+            testRunners.clear();
+            for (int i = 0; i < threads; i++) {
+                Tester tester = (Tester) testClass.newInstance();
+                TestRunner testRunner = new TestRunner(tester);
+                testRunners.add(testRunner);
+                Thread t = new Thread(testRunner);
+                threadList.add(t);
+            }
+            debug("Starting testers");
+            // Now that all testers have been created, start them
+            for (Thread t : threadList) {
+                debug("Starting thread");
+                t.start();
+            }
+        } catch (Exception e) {
+            debug("error in startTesters");
+            throw new IllegalArgumentException("Unable to load class with name " + testClassName, e);
+        }
+        debug("After starting testers");
+    }
+
+    public boolean verify(long generation, long timeout, String verificationFile) throws InterruptedException {
+        Map<String, Map<String, String>> verificationMap = getVerificationMap(verificationFile);
+        for (TestRunner testRunner : testRunners) {
+            long start = System.currentTimeMillis();
+            boolean ok = false;
+            do {
+                if (testRunner.tester.verify(verificationMap, generation)) {
+                    ok = true;
+                }
+                Thread.sleep(10);
+            } while (!ok && (System.currentTimeMillis() - start < timeout));
+            if (!ok) {
+                return false;
+            }
+        }
+        return true;
+    }
+
+    public void stop() {
+        debug("Stopping test runners");
+        for (TestRunner testRunner : testRunners) {
+            testRunner.stop();
+        }
+        debug("Stopping threads");
+        for (Thread t : threadList) {
+            try {
+                t.join();
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+        }
+        debug("End of stop");
+    }
+
+    private static void debug(String s) {
+        if (debug) {
+            System.out.println(s);
+        }
+    }
+
+    public static class RpcServer implements Runnable {
+        private Transport transport = new Transport();
+        protected Supervisor supervisor = new Supervisor(transport);
+        private final Spec spec;
+        private final StressTester tester;
+
+        RpcServer(String host, int port, StressTester tester) {
+            this.tester = tester;
+            setUp(this);
+            spec = new Spec(host, port);
+        }
+
+        public void run() {
+            try {
+                Acceptor acceptor = supervisor.listen(spec);
+                supervisor.transport().join();
+                acceptor.shutdown().join();
+            } catch (ListenFailedException e) {
+                throw new RuntimeException("Could not listen to " + spec);
+            }
+        }
+
+        public void shutdown() {
+            supervisor.transport().shutdown().join();
+        }
+
+        public final void start(Request request) {
+            debug("start: Got " + request);
+            int ret = 1;
+            int clients = request.parameters().get(0).asInt32();
+            debug("start: starting testers");
+            try {
+                tester.startTesters(clients);
+                ret = 0;
+            } catch (Exception e) {
+                debug("start: error: " + e.getMessage());
+                e.printStackTrace();
+            }
+            debug("start: Returning " + ret);
+            request.returnValues().add(new Int32Value(ret));
+        }
+
+        public final void verify(Request request) {
+            debug("verify: Got " + request);
+            long generation = request.parameters().get(0).asInt64();
+            String verificationFile = request.parameters().get(1).asString();
+            long timeout = request.parameters().get(2).asInt64();
+            int ret = 0;
+            String errorMessage = "";
+            try {
+                if (!tester.verify(generation, timeout, verificationFile)) {
+                    ret = 1;
+                    errorMessage = "Unable to get generation " + generation + " within timeout " + timeout;
+                }
+            } catch (Exception e) {
+                ret = 1;
+                errorMessage = e.getMessage();
+                e.printStackTrace();
+            } catch (AssertionError e) {
+                ret = 1;
+                errorMessage = e.getMessage();
+            }
+            debug("verify: Returning " + ret);
+            request.returnValues().add(new Int32Value(ret));
+            request.returnValues().add(new StringValue(errorMessage));
+        }
+
+        public final void stop(Request request) {
+            debug("stop: Got " + request);
+            int ret = 1;
+            try {
+                tester.stop();
+                ret = 0;
+            } catch (Exception e) {
+                e.printStackTrace();
+            }
+            debug("stop: Returning " + ret);
+            request.returnValues().add(new Int32Value(ret));
+        }
+
+        /**
+         * Set up RPC method handlers.
+         *
+         * @param handler a MethodHandler that will handle the RPC methods
+         */
+
+        protected void setUp(Object handler) {
+            supervisor.addMethod(new Method("start", "i", "i",
+                    handler, "start")
+                    .methodDesc("start")
+                    .paramDesc(0, "clients", "number of clients")
+                    .returnDesc(0, "ret code", "return code, 0 is OK"));
+            supervisor.addMethod(new Method("verify", "lsl", "is",
+                    handler, "verify")
+                    .methodDesc("verify")
+                    .paramDesc(0, "generation", "config generation")
+                    .paramDesc(1, "verification file", "name of verification file")
+                    .paramDesc(2, "timeout", "timeout when verifying")
+                    .returnDesc(0, "ret code", "return code, 0 is OK")
+                    .returnDesc(1, "error message", "error message, if non zero return code"));
+            supervisor.addMethod(new Method("stop", "", "i",
+                    handler, "stop")
+                    .methodDesc("stop")
+                    .returnDesc(0, "ret code", "return code, 0 is OK"));
+        }
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/benchmark/Tester.java b/config/src/main/java/com/yahoo/vespa/config/benchmark/Tester.java
new file mode 100644
index 00000000000..68d20f7a75f
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/benchmark/Tester.java
@@ -0,0 +1,14 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.benchmark;
+
+import java.util.Map;
+
+/**
+ * Tester interface for loadable test runners.
+ */
+public interface Tester {
+    public void subscribe();
+    public boolean fetch();
+    public boolean verify(Map<String, Map<String, String>> expected, long generation);
+    public void close();
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/buildergen/CompilationTask.java b/config/src/main/java/com/yahoo/vespa/config/buildergen/CompilationTask.java
new file mode 100644
index 00000000000..04799d47494
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/buildergen/CompilationTask.java
@@ -0,0 +1,45 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.buildergen;
+
+import javax.tools.Diagnostic;
+import javax.tools.DiagnosticCollector;
+import javax.tools.JavaCompiler;
+import javax.tools.JavaFileObject;
+
+/**
+ * Represents a compilation task that can be run and also collects diagnostic messages from the compilation.
+ * TODO: Assumes that diagnostics is the same as given to the task, not ideal.
+ *
+ * @author lulf
+ * @since 5.2
+ */
+class CompilationTask {
+    private final JavaCompiler.CompilationTask task;
+    private final DiagnosticCollector<JavaFileObject> diagnostics;
+
+    CompilationTask(JavaCompiler.CompilationTask task, DiagnosticCollector<JavaFileObject> diagnostics) {
+        this.task = task;
+        this.diagnostics = diagnostics;
+    }
+
+    void call() {
+        boolean success = task.call();
+        if (!success) {
+            throw new IllegalArgumentException("Compilation diagnostics: " + getDiagnosticMessage());
+        }
+    }
+
+    private String getDiagnosticMessage() {
+        StringBuilder diagnosticMessages = new StringBuilder();
+        for (Diagnostic<?> diagnostic : diagnostics.getDiagnostics()) {
+            diagnosticMessages.append(diagnostic.getCode()).append("\n");
+            diagnosticMessages.append(diagnostic.getKind()).append("\n");
+            diagnosticMessages.append(diagnostic.getPosition()).append("\n");
+            diagnosticMessages.append(diagnostic.getStartPosition()).append("\n");
+            diagnosticMessages.append(diagnostic.getEndPosition()).append("\n");
+            diagnosticMessages.append(diagnostic.getSource()).append("\n");
+            diagnosticMessages.append(diagnostic.getMessage(null)).append("\n");
+        }
+        return diagnosticMessages.toString();
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/buildergen/CompiledBuilder.java b/config/src/main/java/com/yahoo/vespa/config/buildergen/CompiledBuilder.java
new file mode 100644
index 00000000000..403ac61b872
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/buildergen/CompiledBuilder.java
@@ -0,0 +1,14 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.buildergen;
+
+import com.yahoo.config.ConfigInstance;
+
+/**
+ * Represents a builder that can be instantiated.
+ *
+ * @author lulf
+ * @since 5.2
+ */
+public interface CompiledBuilder {
+    <BUILDER extends ConfigInstance.Builder> BUILDER newInstance();
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/buildergen/ConfigCompiler.java b/config/src/main/java/com/yahoo/vespa/config/buildergen/ConfigCompiler.java
new file mode 100644
index 00000000000..24b102321d2
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/buildergen/ConfigCompiler.java
@@ -0,0 +1,12 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.buildergen;
+
+/**
+ * Interface towards compilers for compiling builders from a config class definition.
+ *
+ * @author lulf
+ * @since 5.2
+ */
+public interface ConfigCompiler {
+    CompiledBuilder compile(ConfigDefinitionClass defClass);
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/buildergen/ConfigDefinition.java b/config/src/main/java/com/yahoo/vespa/config/buildergen/ConfigDefinition.java
new file mode 100644
index 00000000000..42e7ebe29b9
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/buildergen/ConfigDefinition.java
@@ -0,0 +1,47 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.buildergen;
+
+import com.google.common.io.Files;
+import com.yahoo.config.codegen.DefParser;
+import com.yahoo.config.codegen.InnerCNode;
+import com.yahoo.config.codegen.JavaClassBuilder;
+import com.yahoo.text.StringUtilities;
+
+import java.io.File;
+import java.io.StringReader;
+
+/**
+ * Represents a higher level functionality on a config definition to (in the future) hide the InnerCNode class.
+ * @author lulf
+ */
+public class ConfigDefinition {
+    private final String name;
+    private final String[] defSchema;
+    private final InnerCNode cnode;
+
+    public ConfigDefinition(String name, String[] defSchema) {
+        this.name = name;
+        this.defSchema = defSchema;
+        this.cnode = new DefParser(name, new StringReader(StringUtilities.implode(defSchema, "\n"))).getTree();
+    }
+
+    // TODO: Remove once no fat bundles are using this.
+    public ConfigDefinition(InnerCNode targetDef) {
+        this.name = null;
+        this.defSchema = null;
+        this.cnode = targetDef;
+    }
+
+    public InnerCNode getCNode() {
+        return cnode;
+    }
+
+    public ConfigDefinitionClass generateClass() {
+        File tempDir = Files.createTempDir();
+        DefParser parser = new DefParser(name, new StringReader(StringUtilities.implode(defSchema, "\n")));
+        JavaClassBuilder builder = new JavaClassBuilder(parser.getTree(), parser.getNormalizedDefinition(),  tempDir);
+        String className = builder.className();
+        return new ConfigDefinitionClass(className, builder.javaPackage(), builder.getConfigClass(className));
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/buildergen/ConfigDefinitionClass.java b/config/src/main/java/com/yahoo/vespa/config/buildergen/ConfigDefinitionClass.java
new file mode 100644
index 00000000000..0820d77612e
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/buildergen/ConfigDefinitionClass.java
@@ -0,0 +1,30 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.buildergen;
+
+/**
+ * @author lulf
+ */
+public class ConfigDefinitionClass {
+    private final String name;
+    private final String pkg;
+    private final String definition;
+
+    ConfigDefinitionClass(String name, String pkg, String definition) {
+        this.name = name;
+        this.pkg = pkg;
+        this.definition = definition;
+    }
+
+    String getDefinition() {
+        return definition;
+    }
+
+    String getSimpleName() {
+        return name;
+
+    }
+
+    String getName() {
+        return pkg + "." + name;
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/buildergen/LazyConfigCompiler.java b/config/src/main/java/com/yahoo/vespa/config/buildergen/LazyConfigCompiler.java
new file mode 100644
index 00000000000..957b4a3d3e0
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/buildergen/LazyConfigCompiler.java
@@ -0,0 +1,85 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.buildergen;
+
+import com.yahoo.config.ConfigInstance;
+
+import javax.tools.*;
+import java.io.File;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLClassLoader;
+import java.util.Arrays;
+import java.util.Locale;
+
+/**
+ * Represents a compiler that waits performing the compilation until the requested builder is requested from the
+ * {@link CompiledBuilder}.
+ *
+ * @author lulf
+ * @since 5.2
+ */
+public class LazyConfigCompiler implements ConfigCompiler {
+    private final File outputDirectory;
+    private final ClassLoader classLoader;
+    private final JavaCompiler compiler = ToolProvider.getSystemJavaCompiler();
+
+    public LazyConfigCompiler(File outputDirectory) {
+        this.outputDirectory = outputDirectory;
+        try {
+            this.classLoader = new URLClassLoader(new URL[]{outputDirectory.toURI().toURL()});
+        } catch (MalformedURLException e) {
+            throw new IllegalArgumentException("Unable to create class loader for directory '" + outputDirectory.getAbsolutePath() + "'", e);
+        }
+    }
+
+    @Override
+    public CompiledBuilder compile(ConfigDefinitionClass defClass) {
+        Iterable<? extends JavaFileObject> compilationUnits = Arrays.asList(new StringSourceObject(defClass.getName(), defClass.getDefinition()));
+        DiagnosticCollector<JavaFileObject> diagnostics = new DiagnosticCollector<>();
+
+        StandardJavaFileManager fileManager = compiler.getStandardFileManager(null, Locale.ENGLISH, null);
+        Iterable<String> options = Arrays.asList("-d", outputDirectory.getAbsolutePath());
+        JavaCompiler.CompilationTask task = compiler.getTask(null, fileManager, diagnostics, options, null, compilationUnits);
+        return new LazyCompiledBuilder(classLoader, defClass.getName(), new CompilationTask(task, diagnostics));
+    }
+
+    /**
+     * Lazy implementation of compiled builder that defers compilation until class is requested.
+     */
+    private static class LazyCompiledBuilder implements CompiledBuilder {
+        private final ClassLoader classLoader;
+        private final String classUrl;
+        private final CompilationTask compilationTask;
+        private LazyCompiledBuilder(ClassLoader classLoader, String classUrl, CompilationTask compilationTask) {
+            this.classLoader = classLoader;
+            this.classUrl = classUrl;
+            this.compilationTask = compilationTask;
+        }
+
+        @Override
+        public <BUILDER extends ConfigInstance.Builder> BUILDER newInstance() {
+            compileBuilder();
+            String builderClassUrl = classUrl + "$Builder";
+            return loadBuilder(builderClassUrl);
+
+        }
+
+        private void compileBuilder() {
+            try {
+                compilationTask.call();
+            } catch (IllegalArgumentException e) {
+                throw new IllegalArgumentException("Error compiling '" + classUrl + "'", e);
+            }
+        }
+
+        @SuppressWarnings("unchecked")
+        private <BUILDER extends ConfigInstance.Builder> BUILDER loadBuilder(String builderClassUrl) {
+            try {
+                Class<BUILDER> clazz = (Class<BUILDER>) classLoader.<BUILDER>loadClass(builderClassUrl);
+                return clazz.newInstance();
+            } catch (ClassNotFoundException | IllegalAccessException | InstantiationException e) {
+                throw new RuntimeException("Error creating new instance of '" + builderClassUrl + "'", e);
+            }
+        }
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/buildergen/StringSourceObject.java b/config/src/main/java/com/yahoo/vespa/config/buildergen/StringSourceObject.java
new file mode 100644
index 00000000000..01fc0691d2e
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/buildergen/StringSourceObject.java
@@ -0,0 +1,24 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.buildergen;
+
+import javax.tools.SimpleJavaFileObject;
+import java.net.URI;
+
+/**
+ * Represents an in memory source object that can be compiled.
+ *
+ * @author lulf
+ * @since 5.2
+ */
+class StringSourceObject extends SimpleJavaFileObject {
+    private final String code;
+    StringSourceObject(String name, String code) {
+        super(URI.create("string:///" + name.replace('.', '/') + Kind.SOURCE.extension),Kind.SOURCE);
+        this.code = code;
+    }
+
+    @Override
+    public CharSequence getCharContent(boolean ignoreEncodingErrors) {
+        return code;
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/buildergen/package-info.java b/config/src/main/java/com/yahoo/vespa/config/buildergen/package-info.java
new file mode 100644
index 00000000000..0a0e85ff47c
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/buildergen/package-info.java
@@ -0,0 +1,5 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+@ExportPackage
+package com.yahoo.vespa.config.buildergen;
+
+import com.yahoo.osgi.annotation.ExportPackage;
diff --git a/config/src/main/java/com/yahoo/vespa/config/package-info.java b/config/src/main/java/com/yahoo/vespa/config/package-info.java
new file mode 100644
index 00000000000..9bb8f40a806
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/package-info.java
@@ -0,0 +1,5 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+@ExportPackage
+package com.yahoo.vespa.config;
+
+import com.yahoo.osgi.annotation.ExportPackage;
diff --git a/config/src/main/java/com/yahoo/vespa/config/parser/package-info.java b/config/src/main/java/com/yahoo/vespa/config/parser/package-info.java
new file mode 100644
index 00000000000..4835464c7f7
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/parser/package-info.java
@@ -0,0 +1,5 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+@ExportPackage
+package com.yahoo.vespa.config.parser;
+
+import com.yahoo.osgi.annotation.ExportPackage;
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/CompressionInfo.java b/config/src/main/java/com/yahoo/vespa/config/protocol/CompressionInfo.java
new file mode 100644
index 00000000000..22320ecfa28
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/CompressionInfo.java
@@ -0,0 +1,72 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.yahoo.slime.Inspector;
+
+import java.io.IOException;
+
+/**
+ * Contains info relevant for compression and decompression.
+ *
+ * @author lulf
+ * @since 5.19
+ */
+public class CompressionInfo {
+    private static final String COMPRESSION_TYPE = "compressionType";
+    private static final String UNCOMPRESSED_SIZE = "uncompressedSize";
+
+    public CompressionType getCompressionType() {
+        return compressionType;
+    }
+    public int getUncompressedSize() {
+        return uncompressedSize;
+    }
+
+    private final CompressionType compressionType;
+    private final int uncompressedSize;
+
+    private CompressionInfo(CompressionType compressionType, int uncompressedSize) {
+        this.compressionType = compressionType;
+        this.uncompressedSize = uncompressedSize;
+    }
+
+    public static CompressionInfo uncompressed() {
+        return new CompressionInfo(CompressionType.UNCOMPRESSED, 0);
+    }
+
+    public static CompressionInfo create(CompressionType type, int uncompressedSize) {
+        return new CompressionInfo(type, uncompressedSize);
+    }
+
+    public static CompressionInfo fromSlime(Inspector field) {
+        CompressionType type = CompressionType.parse(field.field(COMPRESSION_TYPE).asString());
+        int uncompressedSize = (int) field.field(UNCOMPRESSED_SIZE).asLong();
+        return new CompressionInfo(type, uncompressedSize);
+    }
+
+    public void serialize(JsonGenerator jsonGenerator) throws IOException {
+        jsonGenerator.writeStringField(COMPRESSION_TYPE, compressionType.name());
+        jsonGenerator.writeNumberField(UNCOMPRESSED_SIZE, uncompressedSize);
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+
+        CompressionInfo that = (CompressionInfo) o;
+
+        if (uncompressedSize != that.uncompressedSize) return false;
+        if (compressionType != that.compressionType) return false;
+
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        int result = compressionType.hashCode();
+        result = 31 * result + uncompressedSize;
+        return result;
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/CompressionType.java b/config/src/main/java/com/yahoo/vespa/config/protocol/CompressionType.java
new file mode 100644
index 00000000000..bf7e79121ea
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/CompressionType.java
@@ -0,0 +1,18 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+/**
+ * @author lulf
+ * @since 5.18
+ */
+public enum CompressionType {
+    UNCOMPRESSED, LZ4;
+    public static CompressionType parse(String value) {
+        for (CompressionType type : CompressionType.values()) {
+            if (type.name().equals(value)) {
+                return type;
+            }
+        }
+        return CompressionType.UNCOMPRESSED;
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/ConfigResponse.java b/config/src/main/java/com/yahoo/vespa/config/protocol/ConfigResponse.java
new file mode 100644
index 00000000000..5e6918c1e88
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/ConfigResponse.java
@@ -0,0 +1,41 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.text.Utf8Array;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.util.List;
+
+/**
+ * A config response encapsulates the payload and some meta information. This makes it possible to
+ * represent the payload in different formats all up to when rendering it to the client. A subclass
+ * of this must be thread safe, because a response may be cached and, the methods below should be callable
+ * from multiple request handler threads.
+ *
+ * @author lulf
+ * @since 5.1.14
+ */
+public interface ConfigResponse {
+
+    Utf8Array getPayload();
+
+    List<String> getLegacyPayload();
+
+    long getGeneration();
+
+    String getConfigMd5();
+
+    void serialize(OutputStream os, CompressionType uncompressed) throws IOException;
+
+    default boolean hasEqualConfig(JRTServerConfigRequest request) {
+        return (getConfigMd5().equals(request.getRequestConfigMd5()));
+    }
+
+    default boolean hasNewerGeneration(JRTServerConfigRequest request) {
+        return (getGeneration() > request.getRequestGeneration());
+    }
+
+    CompressionInfo getCompressionInfo();
+
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/DefContent.java b/config/src/main/java/com/yahoo/vespa/config/protocol/DefContent.java
new file mode 100644
index 00000000000..d22628b7b4a
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/DefContent.java
@@ -0,0 +1,85 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.ConfigurationRuntimeException;
+import com.yahoo.slime.*;
+
+import java.lang.reflect.Field;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.List;
+
+/**
+* @author lulf
+* @since 5.3
+*/
+public class DefContent {
+    private final List<String> data;
+
+    private DefContent(List<String> data) {
+        this.data = data;
+    }
+
+    public String[] asStringArray() {
+        return data.toArray(new String[data.size()]);
+    }
+
+    public List<String> asList() {
+        return data;
+    }
+
+    public String asString() {
+        return com.yahoo.text.StringUtilities.implode(asStringArray(), "\n");
+    }
+
+    static DefContent fromSlime(Inspector data) {
+        final List<String> lst = new ArrayList<>();
+        data.traverse(new ArrayTraverser() {
+            @Override
+            public void entry(int idx, Inspector inspector) {
+                lst.add(inspector.asString());
+            }
+        });
+        return new DefContent(lst);
+    }
+
+    public static DefContent fromClass(Class<? extends ConfigInstance> clazz) {
+        return fromArray(defSchema(clazz));
+    }
+
+    public static DefContent fromList(List<String> def) {
+        return new DefContent(def);
+    }
+
+    public static DefContent fromArray(String[] schema) {
+        return fromList(Arrays.asList(schema));
+    }
+
+    /**
+     * The def file payload of the actual class of the given config
+     * @param configClass the class of a generated config instance
+     * @return a String array with the config definition (one line per element)
+     */
+    private static String[] defSchema(Class<? extends ConfigInstance> configClass) {
+        if (configClass==null) return new String[0];
+        try {
+            Field f = configClass.getField("CONFIG_DEF_SCHEMA");
+            return (String[]) f.get(configClass);
+        } catch (NoSuchFieldException e) {
+            return new String[0];
+        } catch (Exception e) {
+            throw new ConfigurationRuntimeException(e);
+        }
+    }
+
+    public void serialize(final Cursor cursor) {
+        for (String line : data) {
+            cursor.addString(line);
+        }
+    }
+
+    public boolean isEmpty() {
+        return data.isEmpty();
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/JRTClientConfigRequest.java b/config/src/main/java/com/yahoo/vespa/config/protocol/JRTClientConfigRequest.java
new file mode 100644
index 00000000000..8997173a479
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/JRTClientConfigRequest.java
@@ -0,0 +1,88 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+/**
+ * Interface for config requests used by clients.
+ *
+ * @author lulf
+ * @since 5.3
+ */
+public interface JRTClientConfigRequest extends JRTConfigRequest {
+    /**
+     * Validate config response given by the server. If none is given, or an error occurred, this should return false.
+     * @return true if valid response, false if not.
+     */
+    boolean validateResponse();
+
+    /**
+     * Test whether ot not the returned config has an updated generation. This should return false if no response have
+     * been given.
+     * @return true if generation is updated, false if not.
+     */
+    boolean hasUpdatedGeneration();
+
+    /**
+     * Return the payload in the response given by the server. The payload will be empty if no response was given.
+     * @return the config payload.
+     */
+    Payload getNewPayload();
+
+    /**
+     * Create a new {@link JRTClientConfigRequest} based on this request based on the same request parameters, but having
+     * the timeout changed.
+     * @param timeout server timeout of the new request.
+     * @return a new {@link JRTClientConfigRequest} instance.
+     */
+    JRTClientConfigRequest nextRequest(long timeout);
+
+    /**
+     * Test whether or not the returned request is an error.
+     * @return true if error, false if not.
+     */
+    boolean isError();
+
+    /**
+     * Get the generation of the newly provided config. If none has been given, 0 should be returned.
+     * @return the new generation.
+     */
+    long getNewGeneration();
+
+    /**
+     * Get the config md5 of the config returned by the server. Return an empty string if no response has been returned.
+     * @return a config md5.
+     */
+    String getNewConfigMd5();
+
+    /**
+     * For protocols that perform an optimization when no new config has been given, this method will provide the
+     * payload and hasUpdatedConfig state of the previous request.
+     * @param payload a config payload of the previous request.
+     * @param hasUpdatedConfig the hasUpdatedConfig flag of the previous request.
+     */
+    void updateRequestPayload(Payload payload, boolean hasUpdatedConfig);
+
+    /**
+     * Test whether or not the payload is contained in this response or not. Should return false for error responses as well.
+     * @return true if empty, false if not.
+     */
+    boolean containsPayload();
+
+    /**
+     * Test whether or not the response contains an updated config or not. False if no response has been returned.
+     * @return true if config is updated, false if not.
+     */
+    boolean hasUpdatedConfig();
+
+    /**
+     * Get the {@link Trace} given in the response by the server. The {@link Trace} can be used to add further tracing
+     * and later printed to provide useful debug info.
+     * @return a {@link Trace}.
+     */
+    Trace getResponseTrace();
+
+    /**
+     * Get config definition content.
+     * @return def as lines.
+     */
+    DefContent getDefContent();
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/JRTClientConfigRequestV3.java b/config/src/main/java/com/yahoo/vespa/config/protocol/JRTClientConfigRequestV3.java
new file mode 100644
index 00000000000..3f97f066829
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/JRTClientConfigRequestV3.java
@@ -0,0 +1,128 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.subscription.impl.JRTConfigSubscription;
+import com.yahoo.jrt.Request;
+import com.yahoo.text.Utf8Array;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.JRTMethods;
+import com.yahoo.vespa.config.RawConfig;
+import com.yahoo.vespa.config.util.ConfigUtils;
+
+import java.util.Optional;
+
+/**
+ * Represents version 3 config request for config clients. Provides methods for inspecting request and response
+ * values.
+ *
+ * See {@link JRTServerConfigRequestV3} for protocol details.
+ *
+ * @author lulf
+ * @since 5.19
+ */
+public class JRTClientConfigRequestV3 extends SlimeClientConfigRequest {
+
+    protected JRTClientConfigRequestV3(ConfigKey<?> key,
+                                       String hostname,
+                                       DefContent defSchema,
+                                       String configMd5,
+                                       long generation,
+                                       long timeout,
+                                       Trace trace,
+                                       CompressionType compressionType,
+                                       Optional<VespaVersion> vespaVersion) {
+        super(key, hostname, defSchema, configMd5, generation, timeout, trace, compressionType, vespaVersion);
+    }
+
+    @Override
+    protected String getJRTMethodName() {
+        return JRTMethods.configV3getConfigMethodName;
+    }
+
+    @Override
+    protected boolean checkReturnTypes(Request request) {
+        return JRTMethods.checkV3ReturnTypes(request);
+    }
+
+    @Override
+    public Payload getNewPayload() {
+        CompressionInfo compressionInfo = getResponseData().getCompressionInfo();
+        Utf8Array payload = new Utf8Array(request.returnValues().get(1).asData());
+        return Payload.from(payload, compressionInfo);
+    }
+
+    @Override
+    public long getProtocolVersion() {
+        return 3;
+    }
+
+    @Override
+    public JRTClientConfigRequest nextRequest(long timeout) {
+        return new JRTClientConfigRequestV3(getConfigKey(),
+                getClientHostName(),
+                getDefContent(),
+                isError() ? getRequestConfigMd5() : newConfMd5(),
+                isError() ? getRequestGeneration() : newGen(),
+                timeout,
+                Trace.createNew(),
+                requestData.getCompressionType(),
+                requestData.getVespaVersion());
+    }
+
+    public static <T extends ConfigInstance> JRTClientConfigRequest createFromSub(JRTConfigSubscription<T> sub, Trace trace, CompressionType compressionType, Optional<VespaVersion> vespaVersion) {
+        String hostname = ConfigUtils.getCanonicalHostName();
+        ConfigKey<T> key = sub.getKey();
+        T i = sub.getConfig();
+        return createWithParams(key,
+                sub.getDefContent(),
+                hostname,
+                i != null ? i.getConfigMd5() : "",
+                sub.getGeneration() != null ? sub.getGeneration() : 0L,
+                sub.timingValues().getSubscribeTimeout(),
+                trace,
+                compressionType,
+                vespaVersion);
+    }
+
+
+    public static JRTClientConfigRequest createFromRaw(RawConfig config, long serverTimeout, Trace trace, CompressionType compressionType, Optional<VespaVersion> vespaVersion) {
+        String hostname = ConfigUtils.getCanonicalHostName();
+        return createWithParams(config.getKey(),
+                DefContent.fromList(config.getDefContent()),
+                hostname,
+                config.getConfigMd5(),
+                config.getGeneration(),
+                serverTimeout,
+                trace,
+                compressionType,
+                vespaVersion);
+    }
+
+
+    public static JRTClientConfigRequest createWithParams(ConfigKey<?> reqKey,
+                                                          DefContent defContent,
+                                                          String hostname,
+                                                          String configMd5,
+                                                          long generation,
+                                                          long serverTimeout,
+                                                          Trace trace,
+                                                          CompressionType compressionType,
+                                                          Optional<VespaVersion> vespaVersion) {
+        return new JRTClientConfigRequestV3(reqKey,
+                hostname,
+                defContent,
+                configMd5,
+                generation,
+                serverTimeout,
+                trace,
+                compressionType,
+                vespaVersion);
+    }
+
+    @Override
+    public Optional<VespaVersion> getVespaVersion() {
+        return requestData.getVespaVersion();
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/JRTConfigRequest.java b/config/src/main/java/com/yahoo/vespa/config/protocol/JRTConfigRequest.java
new file mode 100644
index 00000000000..98a4ddbf7f1
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/JRTConfigRequest.java
@@ -0,0 +1,94 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.jrt.Request;
+import com.yahoo.vespa.config.ConfigKey;
+
+import java.util.Optional;
+
+/**
+ * Common interface for jrt config requests available both at server and client.
+ * @author lulf
+ * @since 5.3
+ */
+public interface JRTConfigRequest {
+    /**
+     * Get the config key of the config request.
+     * @return a {@link ConfigKey}.
+     */
+    ConfigKey<?> getConfigKey();
+
+    /**
+     * Perform request parameter validation of this config request. This method should be called before fetching
+     * any kind of config protocol-specific parameter.
+     * @return true if valid, false if not.
+     */
+    boolean validateParameters();
+
+    /**
+     * Get the config md5 of the config request. Return an empty string if no response has been returned.
+     * @return a config md5.
+     */
+    String getRequestConfigMd5();
+
+    /**
+     * Get the generation of the requested config. If none has been given, 0 should be returned.
+     * @return the generation in the request.
+     */
+    long getRequestGeneration();
+
+    /**
+     * Get the JRT request object for this config request.
+     * TODO: This method leaks the internal jrt stuff :(
+     * @return a {@link Request} object.
+     */
+    Request getRequest();
+
+    /**
+     * Get a short hand description of this request.
+     * @return a short description
+     */
+    String getShortDescription();
+
+    /**
+     * Get the error code of this request
+     * @return the error code as defined in {@link com.yahoo.vespa.config.ErrorCode}.
+     */
+    int errorCode();
+
+    /**
+     * Return the error message of this request, mostly corresponding to the {@link com.yahoo.vespa.config.ErrorCode}.
+     * @return the error message.
+     */
+    String errorMessage();
+
+    /**
+     * Get the server timeout of this request.
+     * @return the timeout given to the server
+     */
+    long getTimeout();
+
+    /**
+     * Get the config protocol version
+     * @return a protocol version number.
+     */
+    long getProtocolVersion();
+
+    /**
+     * Get the wanted generation for this request.
+     * @return a generation that client would like.
+     */
+    long getWantedGeneration();
+
+    /**
+     * Get the host name of the client that is requesting config.
+     * @return hostname of the client.
+     */
+    String getClientHostName();
+
+    /**
+     * Get the Vespa version of the client that initiated the request
+     * @return Vespa version of the client
+     */
+    Optional<VespaVersion> getVespaVersion();
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/JRTConfigRequestFactory.java b/config/src/main/java/com/yahoo/vespa/config/protocol/JRTConfigRequestFactory.java
new file mode 100644
index 00000000000..583e4ba39f5
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/JRTConfigRequestFactory.java
@@ -0,0 +1,72 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.subscription.impl.JRTConfigSubscription;
+import com.yahoo.vespa.config.RawConfig;
+import com.yahoo.vespa.config.util.ConfigUtils;
+
+import java.util.*;
+import java.util.logging.Logger;
+
+/**
+ * To hide JRT implementations.
+ *
+ * @author lulf
+ * @since 5.3
+ */
+public class JRTConfigRequestFactory {
+
+    public static final String VESPA_CONFIG_PROTOCOL_VERSION = "VESPA_CONFIG_PROTOCOL_VERSION";
+    private final static Logger log = Logger.getLogger(JRTConfigRequestFactory.class.getName());
+    private static final CompressionType compressionType = getCompressionType();
+    private static final String VESPA_CONFIG_PROTOCOL_COMPRESSION = "VESPA_CONFIG_PROTOCOL_COMPRESSION";
+    public static final String VESPA_VERSION = "VESPA_VERSION";
+
+    public static <T extends ConfigInstance> JRTClientConfigRequest createFromSub(JRTConfigSubscription<T> sub) {
+        // TODO: Get trace from caller
+        return JRTClientConfigRequestV3.createFromSub(sub, Trace.createNew(), compressionType, getVespaVersion());
+    }
+
+    public static JRTClientConfigRequest createFromRaw(RawConfig config, long serverTimeout) {
+        // TODO: Get trace from caller
+        return JRTClientConfigRequestV3.createFromRaw(config, serverTimeout, Trace.createNew(), compressionType, getVespaVersion());
+    }
+
+    public static String getProtocolVersion() {
+        return "3";
+    }
+
+    static String getProtocolVersion(String env, String yinstEnv, String property) {
+        return ConfigUtils.getEnvValue("3", env, yinstEnv, property);
+    }
+
+    public static Set<Long> supportedProtocolVersions() {
+        return Collections.singleton(3l);
+    }
+
+    public static CompressionType getCompressionType() {
+        return getCompressionType(System.getenv(VESPA_CONFIG_PROTOCOL_COMPRESSION),
+                System.getenv("services__config_protocol_compression"),
+                System.getProperty(VESPA_CONFIG_PROTOCOL_COMPRESSION));
+    }
+
+    static CompressionType getCompressionType(String env, String yinstEnv, String property) {
+        return CompressionType.valueOf(ConfigUtils.getEnvValue("LZ4", env, yinstEnv, property));
+    }
+
+    static Optional<VespaVersion> getVespaVersion() {
+        final String envValue = ConfigUtils.getEnvValue("", System.getenv(VESPA_VERSION), System.getProperty(VESPA_VERSION));
+        if (envValue != null && !envValue.isEmpty()) {
+            return Optional.of(VespaVersion.fromString(envValue));
+        }
+        return Optional.of(getCompiledVespaVersion());
+    }
+
+    static VespaVersion getCompiledVespaVersion() {
+        return VespaVersion.fromString(String.format("%d.%d.%d",
+                com.yahoo.vespa.config.VespaVersion.major,
+                com.yahoo.vespa.config.VespaVersion.minor,
+                com.yahoo.vespa.config.VespaVersion.micro));
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/JRTServerConfigRequest.java b/config/src/main/java/com/yahoo/vespa/config/protocol/JRTServerConfigRequest.java
new file mode 100644
index 00000000000..e201f1f08ef
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/JRTServerConfigRequest.java
@@ -0,0 +1,68 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.vespa.config.GetConfigRequest;
+
+/**
+ * Interface for config requests at the server end point.
+ *
+ * @author lulf
+ * @since 5.3
+ */
+public interface JRTServerConfigRequest extends JRTConfigRequest, GetConfigRequest {
+    /**
+     * Notify this request that its delayed due to no new config being available at this point. The value
+     * provided in this function should be returned when calling {@link #isDelayedResponse()}.
+     * @param delayedResponse true if response is delayed, false if not.
+     */
+    void setDelayedResponse(boolean delayedResponse);
+
+    /**
+     * Signal error when handling this request. The error should be reflected in the request state and propagated
+     * back to the client.
+     * @param errorCode error code, as described in {@link com.yahoo.vespa.config.ErrorCode}.
+     * @param message message to display for this error, typically printed by client.
+     */
+    void addErrorResponse(int errorCode, String message);
+
+    /**
+     * Signal that the request was handled and provide return values typically needed by a client.
+     * @param payload The config payload that the client should receive.
+     * @param generation The config generation of the given payload.
+     * @param configMd5 The md5sum of the given payload.
+     */
+    void addOkResponse(Payload payload, long generation, String configMd5);
+
+    /**
+     * Get the current config md5 of the client config.
+     * @return a config md5.
+     */
+    String getRequestConfigMd5();
+
+    /**
+     * Get the current config generation of the client config.
+     * @return the current config generation.
+     */
+    long getRequestGeneration();
+
+    /**
+     * Check whether or not this request is delayed.
+     * @return true if delayed, false if not.
+     */
+    boolean isDelayedResponse();
+
+    /**
+     * Get the request trace for this request. The trace can be used to trace config execution to provide useful
+     * debug info in production environments.
+     * @return a {@link Trace} instance.
+     */
+    Trace getRequestTrace();
+
+    /**
+     * Extract the appropriate payload for this request type for a given config response.
+     *
+     * @param response {@link ConfigResponse} to get payload from.
+     * @return A {@link Payload} that satisfies this request format.
+     */
+    Payload payloadFromResponse(ConfigResponse response);
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/JRTServerConfigRequestV3.java b/config/src/main/java/com/yahoo/vespa/config/protocol/JRTServerConfigRequestV3.java
new file mode 100644
index 00000000000..54dcd649d69
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/JRTServerConfigRequestV3.java
@@ -0,0 +1,79 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.yahoo.jrt.DataValue;
+import com.yahoo.jrt.Request;
+import com.yahoo.log.LogLevel;
+import com.yahoo.vespa.config.util.ConfigUtils;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+
+/**
+ * The V3 config protocol implemented on the server side. The V3 protocol uses 2 fields JRT
+ *
+ * * A metadata field containing json data describing config generation, md5 and compression info
+ * * A data field containing compressed or uncompressed json config payload. This field can be empty if the payload
+ *   has not changed since last request, triggering an optimization at the client where the previous payload is used instead.
+ *
+ * The implementation of addOkResponse is optimized for doing as little copying of payload data as possible, ensuring
+ * that we get a lower memory footprint.
+ *
+ * @author lulf
+ * @since 5.19
+ */
+public class JRTServerConfigRequestV3 extends SlimeServerConfigRequest {
+
+    protected JRTServerConfigRequestV3(Request request) {
+        super(request);
+    }
+
+    @Override
+    public void addOkResponse(Payload payload, long generation, String configMd5) {
+        boolean changedConfig = !configMd5.equals(getRequestConfigMd5());
+        boolean changedConfigAndNewGeneration = changedConfig && ConfigUtils.isGenerationNewer(generation, getRequestGeneration());
+        Payload responsePayload = payload.withCompression(getCompressionType());
+        ByteArrayOutputStream byteArrayOutputStream = new NoCopyByteArrayOutputStream(4096);
+        try {
+            JsonGenerator jsonGenerator = createJsonGenerator(byteArrayOutputStream);
+            jsonGenerator.writeStartObject();
+            addCommonReturnValues(jsonGenerator);
+            setResponseField(jsonGenerator, SlimeResponseData.RESPONSE_CONFIG_MD5, configMd5);
+            setResponseField(jsonGenerator, SlimeResponseData.RESPONSE_CONFIG_GENERATION, generation);
+            jsonGenerator.writeObjectFieldStart(SlimeResponseData.RESPONSE_COMPRESSION_INFO);
+            if (responsePayload == null) {
+                throw new RuntimeException("Payload is null for ' " + this + ", not able to create response");
+            }
+            CompressionInfo compressionInfo = responsePayload.getCompressionInfo();
+            // If payload is not being sent, we must adjust compression info to avoid client confusion.
+            if (!changedConfigAndNewGeneration) {
+                compressionInfo = CompressionInfo.create(compressionInfo.getCompressionType(), 0);
+            }
+            compressionInfo.serialize(jsonGenerator);
+            jsonGenerator.writeEndObject();
+            if (log.isLoggable(LogLevel.SPAM)) {
+                log.log(LogLevel.SPAM, getConfigKey() + ": response dataXXXXX" + payload.withCompression(CompressionType.UNCOMPRESSED) + "XXXXX");
+            }
+            jsonGenerator.writeEndObject();
+            jsonGenerator.close();
+        } catch (IOException e) {
+            throw new IllegalArgumentException("Could not add OK response for " + this);
+        }
+        request.returnValues().add(createResponseValue(byteArrayOutputStream));
+        if (changedConfigAndNewGeneration) {
+            request.returnValues().add(new DataValue(responsePayload.getData().getBytes()));
+        } else {
+            request.returnValues().add(new DataValue(new byte[0]));
+        }
+    }
+
+    @Override
+    public long getProtocolVersion() {
+        return 3;
+    }
+
+    public static JRTServerConfigRequestV3 createFromRequest(Request req) {
+        return new JRTServerConfigRequestV3(req);
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/NoCopyByteArrayOutputStream.java b/config/src/main/java/com/yahoo/vespa/config/protocol/NoCopyByteArrayOutputStream.java
new file mode 100644
index 00000000000..d73d0e9a14c
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/NoCopyByteArrayOutputStream.java
@@ -0,0 +1,25 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import java.io.ByteArrayOutputStream;
+
+/**
+ * Subclass of {@link java.io.ByteArrayOutputStream} that gives effective {@link #toByteArray()} method.
+ *
+ * @author lulf
+ * @since 5.19
+ */
+class NoCopyByteArrayOutputStream extends ByteArrayOutputStream {
+    public NoCopyByteArrayOutputStream() {
+        super();
+    }
+
+    public NoCopyByteArrayOutputStream(int initialSize) {
+        super(initialSize);
+    }
+
+    @Override
+    public byte[] toByteArray() {
+        return buf;
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/Payload.java b/config/src/main/java/com/yahoo/vespa/config/protocol/Payload.java
new file mode 100644
index 00000000000..aa0bf374363
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/Payload.java
@@ -0,0 +1,101 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.text.Utf8Array;
+import com.yahoo.text.Utf8String;
+import com.yahoo.vespa.config.ConfigPayload;
+import com.yahoo.vespa.config.LZ4PayloadCompressor;
+
+import java.util.Objects;
+
+/**
+ * An immutable config payload
+ *
+ * @author musum
+ * @author bratseth
+ */
+public class Payload {
+
+    private final Utf8Array data;
+    private final CompressionInfo compressionInfo;
+    private final static LZ4PayloadCompressor compressor = new LZ4PayloadCompressor();
+
+    private Payload(ConfigPayload payload) {
+        this.data = payload.toUtf8Array(true);
+        this.compressionInfo = CompressionInfo.create(CompressionType.UNCOMPRESSED, data.getByteLength());
+    }
+
+    private Payload(Utf8Array payload, CompressionInfo compressionInfo) {
+        Objects.requireNonNull(payload, "Payload");
+        Objects.requireNonNull(compressionInfo, "CompressionInfo");
+        this.data = payload;
+        this.compressionInfo = compressionInfo;
+    }
+
+    public static Payload from(ConfigPayload payload) {
+        return new Payload(payload);
+    }
+
+    /** Creates an uncompressed payload from a string */
+    public static Payload from(String payload) {
+        return new Payload(new Utf8String(payload), CompressionInfo.uncompressed());
+    }
+
+    public static Payload from(String payload, CompressionInfo compressionInfo) {
+        return new Payload(new Utf8String(payload), compressionInfo);
+    }
+
+    /** Creates an uncompressed payload from an Utf8Array */
+    public static Payload from(Utf8Array payload) {
+        return new Payload(payload, CompressionInfo.uncompressed());
+    }
+
+    public static Payload from(Utf8Array payload, CompressionInfo compressionInfo) {
+        return new Payload(payload, compressionInfo);
+    }
+
+    public Utf8Array getData() { return data; }
+
+    /** Returns a copy of this payload where the data is compressed using the given compression */
+    public Payload withCompression(CompressionType requestedCompression) {
+        CompressionType responseCompression = compressionInfo.getCompressionType();
+        if (requestedCompression == CompressionType.UNCOMPRESSED && responseCompression == CompressionType.LZ4) {
+            byte[] buffer = new byte[compressionInfo.getUncompressedSize()];
+            compressor.decompress(data.getBytes(), buffer);
+            Utf8Array data = new Utf8Array(buffer);
+            CompressionInfo info = CompressionInfo.create(CompressionType.UNCOMPRESSED, compressionInfo.getUncompressedSize());
+            return Payload.from(data, info);
+        } else if (requestedCompression == CompressionType.LZ4 && responseCompression == CompressionType.UNCOMPRESSED) {
+            Utf8Array data = new Utf8Array(compressor.compress(this.data.getBytes()));
+            CompressionInfo info = CompressionInfo.create(CompressionType.LZ4, this.data.getByteLength());
+            return Payload.from(data, info);
+        } else {
+            return Payload.from(data, compressionInfo);
+        }
+    }
+
+    public CompressionInfo getCompressionInfo() { return compressionInfo; }
+
+    @Override
+    public String toString() {
+        if (compressionInfo.getCompressionType() == CompressionType.UNCOMPRESSED)
+            return data.toString();
+        else
+            return withCompression(CompressionType.UNCOMPRESSED).toString();
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+
+        Payload other = (Payload) o;
+        return this.compressionInfo.equals(other.compressionInfo) && this.data.equals(other.data);
+    }
+
+    @Override
+    public int hashCode() {
+        return data.hashCode() + 31 * compressionInfo.hashCode();
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/RequestValidation.java b/config/src/main/java/com/yahoo/vespa/config/protocol/RequestValidation.java
new file mode 100644
index 00000000000..d44f9190b42
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/RequestValidation.java
@@ -0,0 +1,92 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.log.LogLevel;
+import com.yahoo.vespa.config.ConfigDefinition;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.ErrorCode;
+
+import java.util.logging.Logger;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+/**
+ * Static utility methods for verifying common request properties.
+ *
+ * @author lulf
+ * @since 5.3
+ */
+public class RequestValidation {
+    private static final Logger log = Logger.getLogger(RequestValidation.class.getName());
+
+    private static final Pattern md5Pattern = Pattern.compile("[0-9a-zA-Z]+");
+
+    public static int validateRequest(JRTConfigRequest request) {
+        ConfigKey<?> key = request.getConfigKey();
+        if (!RequestValidation.verifyName(key.getName())) {
+            log.log(LogLevel.INFO, "Illegal name '" + key.getName() + "'");
+            return ErrorCode.ILLEGAL_NAME;
+        }
+        if (!RequestValidation.verifyNamespace(key.getNamespace())) {
+            log.log(LogLevel.INFO, "Illegal name space '" + key.getNamespace() + "'");
+            return ErrorCode.ILLEGAL_NAME_SPACE;
+        }
+        if (!RequestValidation.verifyMd5(key.getMd5())) {
+            log.log(LogLevel.INFO, "Illegal md5 sum '" + key.getNamespace() + "'");
+            return ErrorCode.ILLEGAL_DEF_MD5;
+        }
+        if (!RequestValidation.verifyMd5(request.getRequestConfigMd5())) {
+            log.log(LogLevel.INFO, "Illegal config md5 '" + request.getRequestConfigMd5() + "'");
+            return ErrorCode.ILLEGAL_CONFIG_MD5;
+        }
+        if (!RequestValidation.verifyGeneration(request.getRequestGeneration())) {
+            log.log(LogLevel.INFO, "Illegal generation '" + request.getRequestGeneration() + "'");
+            return ErrorCode.ILLEGAL_GENERATION;
+        }
+        if (!RequestValidation.verifyGeneration(request.getWantedGeneration())) {
+            log.log(LogLevel.INFO, "Illegal wanted generation '" + request.getWantedGeneration() + "'");
+            return ErrorCode.ILLEGAL_GENERATION;
+        }
+        if (!RequestValidation.verifyTimeout(request.getTimeout())) {
+            log.log(LogLevel.INFO, "Illegal timeout '" + request.getTimeout() + "'");
+            return ErrorCode.ILLEGAL_TIMEOUT;
+        }
+        if (!RequestValidation.verifyHostname(request.getClientHostName())) {
+            log.log(LogLevel.INFO, "Illegal client host name '" + request.getClientHostName() + "'");
+            return ErrorCode.ILLEGAL_CLIENT_HOSTNAME;
+        }
+        return 0;
+    }
+
+    public static boolean verifyName(String name) {
+        Matcher m = ConfigDefinition.namePattern.matcher(name);
+        return m.matches();
+    }
+
+    public static boolean verifyMd5(String md5) {
+        if (md5.equals("")) {
+            return true;  // Empty md5 is ok (e.g. upon getconfig from command line tools)
+        } else if (md5.length() != 32) {
+            return false;
+        }
+        Matcher m = md5Pattern.matcher(md5);
+        return m.matches();
+    }
+
+    public static boolean verifyTimeout(Long timeout) {
+        return (timeout > 0);
+    }
+
+    public static boolean verifyGeneration(Long generation) {
+        return (generation >= 0);
+    }
+
+    private static boolean verifyNamespace(String namespace) {
+        Matcher m = ConfigDefinition.namespacePattern.matcher(namespace);
+        return m.matches();
+    }
+
+    private static boolean verifyHostname(String clientHostName) {
+        return !("".equals(clientHostName));
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeClientConfigRequest.java b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeClientConfigRequest.java
new file mode 100644
index 00000000000..2cb61cac427
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeClientConfigRequest.java
@@ -0,0 +1,230 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.jrt.*;
+import com.yahoo.slime.*;
+import com.yahoo.text.Utf8;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.ErrorCode;
+import com.yahoo.vespa.config.util.ConfigUtils;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.util.Optional;
+import java.util.logging.Logger;
+
+/**
+ * Base class for new generation of config requests based on {@link Slime}. Allows for some customization of
+ * payload encoding and decoding, as well as adding extra request/response fields.
+ *
+ * @author lulf
+ * @since 5.18
+ */
+public abstract class SlimeClientConfigRequest implements JRTClientConfigRequest {
+
+    protected static final Logger log = Logger.getLogger(SlimeClientConfigRequest.class.getName());
+
+    protected final SlimeRequestData requestData;
+    private final SlimeResponseData responseData;
+
+    protected final Request request;
+
+    protected SlimeClientConfigRequest(ConfigKey<?> key,
+                                       String hostname,
+                                       DefContent defSchema,
+                                       String configMd5,
+                                       long generation,
+                                       long timeout,
+                                       Trace trace,
+                                       CompressionType compressionType,
+                                       Optional<VespaVersion> vespaVersion) {
+        Slime data = SlimeRequestData.encodeRequest(key,
+                hostname,
+                defSchema,
+                configMd5,
+                generation,
+                timeout,
+                trace,
+                getProtocolVersion(),
+                compressionType,
+                vespaVersion);
+        Request jrtReq = new Request(getJRTMethodName());
+        jrtReq.parameters().add(new StringValue(encodeAsUtf8String(data, true)));
+
+        this.requestData = new SlimeRequestData(jrtReq, data);
+        this.responseData = new SlimeResponseData(jrtReq);
+        this.request = jrtReq;
+    }
+
+    protected abstract String getJRTMethodName();
+
+    protected static String encodeAsUtf8String(Slime data, boolean compact) {
+        ByteArrayOutputStream baos = new NoCopyByteArrayOutputStream();
+        try {
+            new JsonFormat(compact).encode(baos, data);
+        } catch (IOException e) {
+            throw new RuntimeException("Unable to encode config request", e);
+        }
+        return Utf8.toString(baos.toByteArray());
+    }
+
+    public ConfigKey<?> getConfigKey() {
+        return requestData.getConfigKey();
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append("request='").append(getConfigKey())
+                .append(",").append(getClientHostName())
+                .append(",").append(getRequestConfigMd5())
+                .append(",").append(getRequestGeneration())
+                .append(",").append(getTimeout())
+                .append(",").append(getVespaVersion()).append("'\n");
+        sb.append("response='").append(getNewConfigMd5())
+                .append(",").append(getNewGeneration())
+                .append("'\n");
+        return sb.toString();
+    }
+
+    @Override
+    public String getClientHostName() {
+        return requestData.getClientHostName();
+    }
+
+    @Override
+    public long getWantedGeneration() {
+        return requestData.getWantedGeneration();
+    }
+
+    @Override
+    public Request getRequest() {
+        return request;
+    }
+
+    @Override
+    public int errorCode() {
+        return request.errorCode();
+    }
+
+    @Override
+    public String errorMessage() {
+        return request.errorMessage();
+    }
+
+    @Override
+    public String getShortDescription() {
+        return toString();
+    }
+
+    @Override
+    public boolean hasUpdatedGeneration() {
+        long prevGen = getRequestGeneration();
+        long newGen = getNewGeneration();
+        return ConfigUtils.isGenerationNewer(newGen, prevGen);
+    }
+
+    @Override
+    public long getTimeout() {
+        return requestData.getTimeout();
+    }
+
+    protected String newConfMd5() {
+        String newMd5 = getNewConfigMd5();
+        if ("".equals(newMd5)) return getRequestConfigMd5();
+        return newMd5;
+    }
+
+    protected long newGen() {
+        long newGen = getNewGeneration();
+        if (newGen==0) return getRequestGeneration();
+        return newGen;
+    }
+
+    @Override
+    public DefContent getDefContent() {
+        return requestData.getSchema();
+    }
+
+    @Override
+    public boolean isError() {
+        return request.isError();
+    }
+
+    @Override
+    public void updateRequestPayload(Payload payload, boolean hasUpdatedConfig) {
+        // This protocol sends payload in all cases, so ignore this.
+    }
+
+    @Override
+    public boolean containsPayload() {
+        return false;
+    }
+
+    @Override
+    public boolean hasUpdatedConfig() {
+        String respMd5 = getNewConfigMd5();
+        return !respMd5.equals("") && !getRequestConfigMd5().equals(respMd5);
+    }
+
+    @Override
+    public Trace getResponseTrace() {
+        return responseData.getResponseTrace();
+    }
+
+    @Override
+    public String getRequestConfigMd5() {
+        return requestData.getRequestConfigMd5();
+    }
+
+    @Override
+    public boolean validateResponse() {
+        if (request.isError()) {
+            return false;
+        } else if (request.returnValues().size() == 0) {
+            return false;
+        } else if (!checkReturnTypes(request)) {
+            log.warning("Invalid return types for config response: " + errorMessage());
+            return false;
+        }
+        if (hasUpdatedConfig() && ! hasUpdatedGeneration()) {
+            request.setError(ErrorCode.OUTDATED_CONFIG, "Config payload has changed (old config md5:" +
+                    getRequestConfigMd5() + ", new config md5: " + getNewConfigMd5() +"), but new generation " +
+                    getNewGeneration() + " is not newer than current generation " + getRequestGeneration()  + ".");
+            return false;
+        }
+        return true;
+    }
+
+    @Override
+    public boolean validateParameters() {
+        int errorCode = RequestValidation.validateRequest(this);
+        return (errorCode == 0);
+    }
+
+    protected abstract boolean checkReturnTypes(Request request);
+
+    @Override
+    public String getNewConfigMd5() {
+        return responseData.getResponseConfigMd5();
+    }
+
+    @Override
+    public long getNewGeneration() {
+        return responseData.getResponseConfigGeneration();
+    }
+
+    @Override
+    public long getRequestGeneration() {
+        return requestData.getRequestGeneration();
+    }
+
+    protected SlimeResponseData getResponseData() {
+        return responseData;
+    }
+
+    public Optional<VespaVersion> getVespaVersion() {
+        return requestData.getVespaVersion();
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeConfigResponse.java b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeConfigResponse.java
new file mode 100644
index 00000000000..d5c4fc638ee
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeConfigResponse.java
@@ -0,0 +1,84 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.config.codegen.InnerCNode;
+import com.yahoo.text.Utf8Array;
+import com.yahoo.vespa.config.ConfigFileFormat;
+import com.yahoo.vespa.config.ConfigPayload;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.OutputStream;
+import java.util.Arrays;
+import java.util.List;
+
+/**
+ * Class for serializing config responses based on {@link com.yahoo.slime.Slime} implementing the {@link ConfigResponse} interface.
+ *
+ * @author lulf
+ * @since 5.1
+ */
+public class SlimeConfigResponse implements ConfigResponse {
+
+    private final Utf8Array payload;
+    private final CompressionInfo compressionInfo;
+    private final InnerCNode targetDef;
+    private final long generation;
+    private final String configMd5;
+
+    public static SlimeConfigResponse fromConfigPayload(ConfigPayload payload, InnerCNode targetDef, long generation, String configMd5) {
+        Utf8Array data = payload.toUtf8Array(true);
+        return new SlimeConfigResponse(data, targetDef, generation, configMd5, CompressionInfo.create(CompressionType.UNCOMPRESSED, data.getByteLength()));
+    }
+
+    public SlimeConfigResponse(Utf8Array payload, InnerCNode targetDef, long generation, String configMd5, CompressionInfo compressionInfo) {
+        this.payload = payload;
+        this.targetDef = targetDef;
+        this.generation = generation;
+        this.configMd5 = configMd5;
+        this.compressionInfo = compressionInfo;
+    }
+
+    @Override
+    public Utf8Array getPayload() {
+        return payload;
+    }
+
+    @Override
+    public List<String> getLegacyPayload() {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        ConfigFileFormat format = new ConfigFileFormat(targetDef);
+        Payload v1payload = Payload.from(payload, compressionInfo).withCompression(CompressionType.UNCOMPRESSED);
+        try {
+            ConfigPayload.fromUtf8Array(v1payload.getData()).serialize(baos, format);
+            return Arrays.asList(baos.toString("UTF-8").split("\\n"));
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    @Override
+    public long getGeneration() {
+        return generation;
+    }
+
+    @Override
+    public String getConfigMd5() {
+        return configMd5;
+    }
+
+    @Override
+    public void serialize(OutputStream os, CompressionType type) throws IOException {
+        os.write(Payload.from(payload, compressionInfo).withCompression(type).getData().getBytes());
+    }
+
+    @Override
+    public String toString() {
+        return "generation=" + generation +  "\n" +
+                "configmd5=" + configMd5 +  "\n" +
+                Payload.from(payload, compressionInfo).withCompression(CompressionType.UNCOMPRESSED);
+    }
+
+    @Override
+    public CompressionInfo getCompressionInfo() { return compressionInfo; }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeRequestData.java b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeRequestData.java
new file mode 100644
index 00000000000..80c050b9b61
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeRequestData.java
@@ -0,0 +1,138 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.jrt.Request;
+import com.yahoo.slime.Cursor;
+import com.yahoo.slime.Inspector;
+import com.yahoo.slime.JsonDecoder;
+import com.yahoo.slime.Slime;
+import com.yahoo.text.Utf8;
+import com.yahoo.vespa.config.ConfigKey;
+
+import java.util.Optional;
+
+/**
+ * Contains slime request data objects. Provides methods for reading various fields from slime request data. All
+ * data is read lazily.
+ *
+* @author lulf
+* @since 5.18
+*/
+class SlimeRequestData {
+
+    private static final String REQUEST_VERSION = "version";
+    private static final String REQUEST_DEF_NAME = "defName";
+    private static final String REQUEST_DEF_NAMESPACE = "defNamespace";
+    private static final String REQUEST_DEF_CONTENT = "defContent";
+    private static final String REQUEST_CLIENT_CONFIGID = "configId";
+    private static final String REQUEST_CLIENT_HOSTNAME = "clientHostname";
+    private static final String REQUEST_CURRENT_GENERATION = "currentGeneration";
+    private static final String REQUEST_WANTED_GENERATION = "wantedGeneration";
+    private static final String REQUEST_CONFIG_MD5 = "configMD5";
+    private static final String REQUEST_TRACE = "trace";
+    private static final String REQUEST_TIMEOUT = "timeout";
+    private static final String REQUEST_DEF_MD5 = "defMD5";
+    private static final String REQUEST_COMPRESSION_TYPE = "compressionType";
+    private static final String REQUEST_VESPA_VERSION = "vespaVersion";
+
+    private final Request request;
+    private Slime data = null;
+
+    SlimeRequestData(Request request) {
+        this.request = request;
+    }
+
+    SlimeRequestData(Request request, Slime data) {
+        this.request = request;
+        this.data = data;
+    }
+
+    private Slime getData() {
+        if (data == null) {
+            data = new JsonDecoder().decode(new Slime(), Utf8.toBytes(request.parameters().get(0).asString()));
+        }
+        return data;
+    }
+
+    Inspector getRequestField(String requestField) {
+        return getData().get().field(requestField);
+    }
+
+    ConfigKey<?> getConfigKey() {
+        return ConfigKey.createFull(getRequestField(REQUEST_DEF_NAME).asString(),
+                getRequestField(REQUEST_CLIENT_CONFIGID).asString(),
+                getRequestField(REQUEST_DEF_NAMESPACE).asString(),
+                getRequestField(REQUEST_DEF_MD5).asString());
+    }
+
+    DefContent getSchema() {
+        Inspector content = getRequestField(REQUEST_DEF_CONTENT);
+        return DefContent.fromSlime(content);
+    }
+
+    String getClientHostName() {
+        return getRequestField(REQUEST_CLIENT_HOSTNAME).asString();
+    }
+
+    long getWantedGeneration() {
+        return getRequestField(REQUEST_WANTED_GENERATION).asLong();
+    }
+
+    long getTimeout() {
+        return getRequestField(REQUEST_TIMEOUT).asLong();
+    }
+
+    String getRequestConfigMd5() {
+        return getRequestField(REQUEST_CONFIG_MD5).asString();
+    }
+
+    long getRequestGeneration() {
+        return getRequestField(REQUEST_CURRENT_GENERATION).asLong();
+    }
+
+    static Slime encodeRequest(ConfigKey<?> key,
+                               String hostname,
+                               DefContent defSchema,
+                               String configMd5,
+                               long generation,
+                               long timeout,
+                               Trace trace,
+                               long protocolVersion,
+                               CompressionType compressionType,
+                               Optional<VespaVersion> vespaVersion) {
+        Slime data = new Slime();
+        Cursor request = data.setObject();
+        request.setLong(REQUEST_VERSION, protocolVersion);
+        request.setString(REQUEST_DEF_NAME, key.getName());
+        request.setString(REQUEST_DEF_NAMESPACE, key.getNamespace());
+        request.setString(REQUEST_DEF_MD5, key.getMd5());
+        request.setString(REQUEST_CLIENT_CONFIGID, key.getConfigId());
+        request.setString(REQUEST_CLIENT_HOSTNAME, hostname);
+        defSchema.serialize(request.setArray(REQUEST_DEF_CONTENT));
+        request.setString(REQUEST_CONFIG_MD5, configMd5);
+        request.setLong(REQUEST_CURRENT_GENERATION, generation);
+        request.setLong(REQUEST_WANTED_GENERATION, 0l);
+        request.setLong(REQUEST_TIMEOUT, timeout);
+        request.setString(REQUEST_COMPRESSION_TYPE, compressionType.name());
+        if (vespaVersion.isPresent()) {
+            request.setString(REQUEST_VESPA_VERSION, vespaVersion.get().toString());
+        }
+        trace.serialize(request.setObject(REQUEST_TRACE));
+        return data;
+    }
+
+    Trace getRequestTrace() {
+        return Trace.fromSlime(getRequestField(REQUEST_TRACE));
+    }
+
+    public CompressionType getCompressionType() {
+        Inspector field = getRequestField(REQUEST_COMPRESSION_TYPE);
+        return field.valid() ? CompressionType.parse(field.asString()) : CompressionType.UNCOMPRESSED;
+    }
+
+    public Optional<VespaVersion> getVespaVersion() {
+        String versionString = getRequestField(REQUEST_VESPA_VERSION).asString(); // will be "" if not set, never null
+        return versionString.isEmpty() ? Optional.<VespaVersion>empty() : Optional.of(VespaVersion.fromString(versionString));
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeResponseData.java b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeResponseData.java
new file mode 100644
index 00000000000..8899658730c
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeResponseData.java
@@ -0,0 +1,69 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.jrt.Request;
+import com.yahoo.slime.Inspector;
+import com.yahoo.slime.JsonDecoder;
+import com.yahoo.slime.Slime;
+import com.yahoo.text.Utf8;
+
+/**
+ * Contains response data for a slime response and methods for decoding the response data that
+ * are common to all {@link Slime} based config requests.
+ *
+ * @author lulf
+ * @since 5.18
+ */
+class SlimeResponseData {
+    static final String RESPONSE_VERSION = "version";
+    static final String RESPONSE_DEF_NAME = "defName";
+    static final String RESPONSE_DEF_NAMESPACE = "defNamespace";
+    static final String RESPONSE_DEF_MD5 = "defMD5";
+    static final String RESPONSE_CONFIGID = "configId";
+    static final String RESPONSE_CLIENT_HOSTNAME = "clientHostname";
+    static final String RESPONSE_TRACE = "trace";
+    static final String RESPONSE_CONFIG_MD5 = "configMD5";
+    static final String RESPONSE_CONFIG_GENERATION = "generation";
+    static final String RESPONSE_COMPRESSION_INFO = "compressionInfo";
+
+    private final Request request;
+    private Slime data = null;
+
+    SlimeResponseData(Request request) {
+        this.request = request;
+    }
+
+    private Slime getData() {
+        if (request.returnValues().size() > 0) {
+            if (data == null) {
+                data = new JsonDecoder().decode(new Slime(), Utf8.toBytes(request.returnValues().get(0).asString()));
+            }
+            return data;
+        } else {
+            return new Slime();
+        }
+    }
+
+    Inspector getResponseField(String responseTrace) {
+        return getData().get().field(responseTrace);
+    }
+
+    long getResponseConfigGeneration() {
+        Inspector inspector = getResponseField(RESPONSE_CONFIG_GENERATION);
+        return inspector.valid() ? inspector.asLong() : -1;
+    }
+
+    Trace getResponseTrace() {
+        Inspector trace = getResponseField(RESPONSE_TRACE);
+        return trace.valid() ? Trace.fromSlime(trace) : Trace.createDummy();
+    }
+
+    String getResponseConfigMd5() {
+        Inspector inspector = getResponseField(RESPONSE_CONFIG_MD5);
+        return inspector.valid() ? inspector.asString() : "";
+    }
+
+    CompressionInfo getCompressionInfo() {
+        return CompressionInfo.fromSlime(getResponseField(RESPONSE_COMPRESSION_INFO));
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeServerConfigRequest.java b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeServerConfigRequest.java
new file mode 100644
index 00000000000..8eabcd7eb26
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeServerConfigRequest.java
@@ -0,0 +1,206 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.fasterxml.jackson.core.JsonFactory;
+import com.fasterxml.jackson.core.JsonGenerator;
+import com.yahoo.jrt.*;
+import com.yahoo.slime.*;
+import com.yahoo.text.Utf8Array;
+import com.yahoo.vespa.config.*;
+import com.yahoo.vespa.config.ErrorCode;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.util.Optional;
+import java.util.logging.Logger;
+
+/**
+ * Base class for new generation of config requests based on {@link Slime}. Allows for some customization of
+ * payload encoding and decoding, as well as adding extra request/response fields. Used by both V2 and V3
+ * config protocol.
+ *
+ * @author lulf
+ * @since 5.18
+ */
+abstract class SlimeServerConfigRequest implements JRTServerConfigRequest {
+
+    protected static final Logger log = Logger.getLogger(SlimeServerConfigRequest.class.getName());
+
+    private static final JsonFactory jsonFactory = new JsonFactory();
+
+    private final SlimeRequestData requestData;
+
+    // Response values
+    private boolean isDelayed = false;
+    private Trace requestTrace = null;
+    protected final Request request;
+
+    protected SlimeServerConfigRequest(Request request) {
+        this.requestData = new SlimeRequestData(request);
+        this.request = request;
+    }
+
+    protected static JsonGenerator createJsonGenerator(ByteArrayOutputStream byteArrayOutputStream) throws IOException {
+        return jsonFactory.createGenerator(byteArrayOutputStream);
+    }
+
+    @Override
+    public ConfigKey<?> getConfigKey() {
+        return requestData.getConfigKey();
+    }
+
+    @Override
+    public DefContent getDefContent() {
+        return getSchema();
+    }
+
+    @Override
+    public boolean noCache() {
+        return false;
+    }
+
+    @Override
+    public String toString() {
+        StringBuilder sb = new StringBuilder();
+        sb.append("request='").append(getConfigKey())
+                .append(",").append(getClientHostName())
+                .append(",").append(getRequestConfigMd5())
+                .append(",").append(getRequestGeneration())
+                .append(",").append(getTimeout()).append("'\n");
+        return sb.toString();
+    }
+
+    @Override
+    public Payload payloadFromResponse(ConfigResponse response) {
+        return Payload.from(response.getPayload(), response.getCompressionInfo());
+    }
+
+    private DefContent getSchema() {
+        return requestData.getSchema();
+    }
+
+    @Override
+    public long getWantedGeneration() {
+        return requestData.getWantedGeneration();
+    }
+
+    @Override
+    public String getClientHostName() {
+        return requestData.getClientHostName();
+    }
+
+    public Trace getRequestTrace() {
+        if (requestTrace == null) {
+            requestTrace = requestData.getRequestTrace();
+        }
+        return requestTrace;
+    }
+
+    @Override
+    public Request getRequest() {
+        return request;
+    }
+
+    @Override
+    public boolean validateParameters() {
+        int errorCode = RequestValidation.validateRequest(this);
+        if (errorCode != 0) {
+            addErrorResponse(errorCode);
+        }
+        return (errorCode == 0);
+    }
+
+    @Override
+    public String getRequestConfigMd5() {
+        return requestData.getRequestConfigMd5();
+    }
+
+    private void addErrorResponse(int errorCode) {
+        addErrorResponse(errorCode, ErrorCode.getName(errorCode));
+    }
+
+    @Override
+    public void setDelayedResponse(boolean delayedResponse) {
+        this.isDelayed = delayedResponse;
+    }
+
+    @Override
+    public void addErrorResponse(int errorCode, String name) {
+        ByteArrayOutputStream byteArrayOutputStream = new NoCopyByteArrayOutputStream();
+        try {
+            JsonGenerator jsonWriter = jsonFactory.createGenerator(byteArrayOutputStream);
+            jsonWriter.writeStartObject();
+            addCommonReturnValues(jsonWriter);
+            jsonWriter.writeEndObject();
+            jsonWriter.close();
+        } catch (IOException e) {
+            throw new IllegalArgumentException("Could not add error response for " + this);
+        }
+        request.setError(errorCode, name);
+        request.returnValues().add(createResponseValue(byteArrayOutputStream));
+    }
+
+    protected static Value createResponseValue(ByteArrayOutputStream byteArrayOutputStream) {
+        return new StringValue(new Utf8Array(byteArrayOutputStream.toByteArray()));
+    }
+
+    protected void addCommonReturnValues(JsonGenerator jsonGenerator) throws IOException {
+        ConfigKey<?> key = requestData.getConfigKey();
+        setResponseField(jsonGenerator, SlimeResponseData.RESPONSE_VERSION, getProtocolVersion());
+        setResponseField(jsonGenerator, SlimeResponseData.RESPONSE_DEF_NAME, key.getName());
+        setResponseField(jsonGenerator, SlimeResponseData.RESPONSE_DEF_NAMESPACE, key.getNamespace());
+        setResponseField(jsonGenerator, SlimeResponseData.RESPONSE_DEF_MD5, key.getMd5());
+        setResponseField(jsonGenerator, SlimeResponseData.RESPONSE_CONFIGID, key.getConfigId());
+        setResponseField(jsonGenerator, SlimeResponseData.RESPONSE_CLIENT_HOSTNAME, requestData.getClientHostName());
+        jsonGenerator.writeFieldName(SlimeResponseData.RESPONSE_TRACE);
+        jsonGenerator.writeRawValue(getRequestTrace().toString(true));
+    }
+
+    protected static void setResponseField(JsonGenerator jsonGenerator, String fieldName, String value) throws IOException {
+        jsonGenerator.writeStringField(fieldName, value);
+    }
+
+    protected static void setResponseField(JsonGenerator jsonGenerator, String fieldName, long value) throws IOException {
+        jsonGenerator.writeNumberField(fieldName, value);
+    }
+
+    @Override
+    public long getRequestGeneration() {
+        return requestData.getRequestGeneration();
+    }
+
+    @Override
+    public boolean isDelayedResponse() {
+        return isDelayed;
+    }
+
+    @Override
+    public int errorCode() {
+        return request.errorCode();
+    }
+
+    @Override
+    public String errorMessage() {
+        return request.errorMessage();
+    }
+
+    @Override
+    public String getShortDescription() {
+        return toString();
+    }
+
+    protected CompressionType getCompressionType() {
+        return requestData.getCompressionType();
+    }
+
+    @Override
+    public long getTimeout() {
+        return requestData.getTimeout();
+    }
+
+    @Override
+    public Optional<VespaVersion> getVespaVersion() {
+        return requestData.getVespaVersion();
+    }
+
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeTraceDeserializer.java b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeTraceDeserializer.java
new file mode 100644
index 00000000000..a4074a43a81
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeTraceDeserializer.java
@@ -0,0 +1,58 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.slime.ArrayTraverser;
+import com.yahoo.slime.Inspector;
+import com.yahoo.yolean.trace.TraceNode;
+
+/**
+ * Deserializing from a {@link Inspector} (slime) representation to a {@link TraceNode}
+ *
+ * @author lulf
+ * @since 5.5
+ */
+public class SlimeTraceDeserializer {
+    private final Inspector entry;
+    public SlimeTraceDeserializer(Inspector inspector) {
+        this.entry = inspector;
+    }
+
+    public TraceNode deserialize() {
+        return deserialize(entry);
+    }
+
+    private static TraceNode deserialize(Inspector entry) {
+        Object payload = decodePayload(entry.field(SlimeTraceSerializer.PAYLOAD));
+        long timestamp = decodeTimestamp(entry.field(SlimeTraceSerializer.TIMESTAMP));
+        final TraceNode node = new TraceNode(payload, timestamp);
+        Inspector children = entry.field(SlimeTraceSerializer.CHILDREN);
+        children.traverse(new ArrayTraverser() {
+            @Override
+            public void entry(int idx, Inspector inspector) {
+                node.add(deserialize(inspector));
+            }
+        });
+        return node;
+    }
+
+    private static long decodeTimestamp(Inspector entry) {
+        return entry.asLong();
+    }
+
+    private static Object decodePayload(Inspector entry) {
+        switch (entry.type()) {
+            case STRING:
+                return entry.asString();
+            case LONG:
+                return entry.asLong();
+            case BOOL:
+                return entry.asBool();
+            case DOUBLE:
+                return entry.asDouble();
+            case DATA:
+                return entry.asData();
+            default:
+                return null;
+        }
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeTraceSerializer.java b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeTraceSerializer.java
new file mode 100644
index 00000000000..ea4151e9e36
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/SlimeTraceSerializer.java
@@ -0,0 +1,60 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.slime.Cursor;
+import com.yahoo.yolean.trace.TraceNode;
+import com.yahoo.yolean.trace.TraceVisitor;
+
+import java.util.Iterator;
+import java.util.Stack;
+
+/**
+ * Serialize a {@link TraceNode} to {@link com.yahoo.slime.Slime}.
+ *
+ * @author lulf
+ * @since 5.5
+ */
+public class SlimeTraceSerializer extends TraceVisitor {
+    static final String TIMESTAMP = "timestamp";
+    static final String PAYLOAD = "payload";
+    static final String CHILDREN = "children";
+    final Stack<Cursor> cursors = new Stack<>();
+
+    public SlimeTraceSerializer(Cursor cursor) {
+        cursors.push(cursor);
+    }
+
+    @Override
+    public void visit(TraceNode node) {
+        Cursor current = cursors.pop();
+        current.setLong(TIMESTAMP, node.timestamp());
+        encodePayload(current, node.payload());
+        addChildrenCursors(current, node);
+
+    }
+
+    private void encodePayload(Cursor current, Object payload) {
+        if (payload instanceof String) {
+            current.setString(PAYLOAD, (String)payload);
+        } else if (payload instanceof Long) {
+            current.setLong(PAYLOAD, (Long) payload);
+        } else if (payload instanceof Boolean) {
+            current.setBool(PAYLOAD, (Boolean) payload);
+        } else if (payload instanceof Double) {
+            current.setDouble(PAYLOAD, (Double) payload);
+        } else if (payload instanceof byte[]) {
+            current.setData(PAYLOAD, (byte[]) payload);
+        }
+    }
+
+    private void addChildrenCursors(Cursor current, TraceNode node) {
+        Iterator<TraceNode> it = node.children().iterator();
+        if (it.hasNext()) {
+            Cursor childrenArray = current.setArray(CHILDREN);
+            while (it.hasNext()) {
+                cursors.push(childrenArray.addObject());
+                it.next();
+            }
+        }
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/Trace.java b/config/src/main/java/com/yahoo/vespa/config/protocol/Trace.java
new file mode 100644
index 00000000000..58ec5024cbb
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/Trace.java
@@ -0,0 +1,102 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.slime.*;
+import com.yahoo.text.Utf8;
+import com.yahoo.yolean.trace.TraceNode;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.time.Clock;
+
+/**
+ * A trace utility that can serialize/deserialize to/from {@link Slime}
+ *
+ * @author lulf
+ * @since 5.3
+ */
+public class Trace {
+    private static final String TRACE_TRACELOG = "traceLog";
+    private static final String TRACE_TRACELEVEL = "traceLevel";
+    private final int traceLevel;
+    private final TraceNode traceNode;
+    private final Clock clock;
+
+    private Trace(int traceLevel, TraceNode traceNode, Clock clock) {
+        this.traceLevel = traceLevel;
+        this.traceNode = traceNode;
+        this.clock = clock;
+    }
+
+
+    public void trace(int level, String message) {
+        if (shouldTrace(level)) {
+            addTrace(message);
+        }
+    }
+
+    private void addTrace(String message) {
+        traceNode.add(new TraceNode(message, clock.millis()));
+    }
+
+    public static Trace createNew(int traceLevel, Clock clock) {
+        return new Trace(traceLevel, new TraceNode(null, clock.millis()), clock);
+    }
+
+    public static Trace createNew(int traceLevel) {
+        return createNew(traceLevel, Clock.systemUTC());
+    }
+
+    public static Trace fromSlime(Inspector inspector) {
+        int traceLevel = deserializeTraceLevel(inspector);
+        Clock clock = Clock.systemUTC();
+        SlimeTraceDeserializer deserializer = new SlimeTraceDeserializer(inspector.field(TRACE_TRACELOG));
+        return new Trace(traceLevel, deserializer.deserialize(), clock);
+    }
+
+    private static int deserializeTraceLevel(Inspector inspector) {
+        return (int) inspector.field(TRACE_TRACELEVEL).asLong();
+    }
+
+    public void serialize(Cursor cursor) {
+        cursor.setLong(TRACE_TRACELEVEL, traceLevel);
+        SlimeTraceSerializer serializer = new SlimeTraceSerializer(cursor.setObject(TRACE_TRACELOG));
+        traceNode.accept(serializer);
+    }
+
+    public static Trace createDummy() {
+        return Trace.createNew(0);
+    }
+
+    public int getTraceLevel() {
+        return traceLevel;
+    }
+
+    public boolean shouldTrace(int level) {
+        return level <= traceLevel;
+    }
+
+    public String toString(boolean compact) {
+        Slime slime = new Slime();
+        serialize(slime.setObject());
+        JsonFormat format = new JsonFormat(compact);
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        try {
+            format.encode(baos, slime);
+        } catch (IOException e) {
+            throw new IllegalArgumentException("Unable to encode trace as JSON", e);
+        }
+        return Utf8.toString(baos.toByteArray());
+    }
+
+
+    @Override
+    public String toString() {
+        return toString(false);
+    }
+
+    private final static int systemTraceLevel = Integer.getInteger("config.protocol.traceLevel", 0);
+    public static Trace createNew() {
+        return createNew(systemTraceLevel);
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/Utf8SerializedString.java b/config/src/main/java/com/yahoo/vespa/config/protocol/Utf8SerializedString.java
new file mode 100644
index 00000000000..b715792f05e
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/Utf8SerializedString.java
@@ -0,0 +1,87 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.fasterxml.jackson.core.SerializableString;
+import com.yahoo.text.Utf8Array;
+
+import java.io.IOException;
+import java.io.OutputStream;
+import java.nio.ByteBuffer;
+
+/**
+ * Wraps utf8array as a {@link com.fasterxml.jackson.core.SerializableString} to avoid extra copy.
+ *
+ * @author lulf
+ * @since 5.17
+ */
+public class Utf8SerializedString implements SerializableString {
+    private final Utf8Array value;
+    public Utf8SerializedString(Utf8Array value) {
+        this.value = value;
+    }
+
+    @Override
+    public String getValue() {
+        return value.toString();
+    }
+
+    @Override
+    public int charLength() {
+        return value.getByteLength();
+    }
+
+    @Override
+    public char[] asQuotedChars() {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public byte[] asUnquotedUTF8() {
+        return value.getBytes();
+    }
+
+    @Override
+    public byte[] asQuotedUTF8() {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public int appendQuotedUTF8(byte[] buffer, int offset) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public int appendQuoted(char[] buffer, int offset) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public int appendUnquotedUTF8(byte[] buffer, int offset) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public int appendUnquoted(char[] buffer, int offset) {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public int writeQuotedUTF8(OutputStream out) throws IOException {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public int writeUnquotedUTF8(OutputStream out) throws IOException {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public int putQuotedUTF8(ByteBuffer buffer) throws IOException {
+        throw new UnsupportedOperationException();
+    }
+
+    @Override
+    public int putUnquotedUTF8(ByteBuffer out) throws IOException {
+        throw new UnsupportedOperationException();
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/VespaVersion.java b/config/src/main/java/com/yahoo/vespa/config/protocol/VespaVersion.java
new file mode 100644
index 00000000000..748cdce4e25
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/VespaVersion.java
@@ -0,0 +1,42 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+/**
+ * A wrapper class for Vespa version
+ *
+ * @author musum
+ * @since 5.39
+ */
+public class VespaVersion {
+    private final String version;
+
+    public static VespaVersion fromString(String version) {
+        return new VespaVersion(version);
+    }
+
+    private VespaVersion(String version) {
+        this.version = version;
+    }
+
+    @Override
+    public boolean equals(Object o) {
+        if (this == o) return true;
+        if (o == null || getClass() != o.getClass()) return false;
+
+        VespaVersion that = (VespaVersion) o;
+
+        if (!version.equals(that.version)) return false;
+
+        return true;
+    }
+
+    @Override
+    public int hashCode() {
+        return version.hashCode();
+    }
+
+    @Override
+    public String toString() {
+        return version;
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/protocol/package-info.java b/config/src/main/java/com/yahoo/vespa/config/protocol/package-info.java
new file mode 100644
index 00000000000..5a6398eda96
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/protocol/package-info.java
@@ -0,0 +1,5 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+@ExportPackage
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.osgi.annotation.ExportPackage;
diff --git a/config/src/main/java/com/yahoo/vespa/config/util/ConfigUtils.java b/config/src/main/java/com/yahoo/vespa/config/util/ConfigUtils.java
new file mode 100644
index 00000000000..b79ff278e57
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/util/ConfigUtils.java
@@ -0,0 +1,454 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.util;
+
+import com.yahoo.collections.Tuple2;
+import com.yahoo.config.codegen.CNode;
+import com.yahoo.io.HexDump;
+import com.yahoo.io.IOUtils;
+import com.yahoo.slime.JsonFormat;
+import com.yahoo.text.Utf8;
+import com.yahoo.text.Utf8Array;
+import com.yahoo.vespa.config.*;
+
+import java.io.*;
+import java.net.UnknownHostException;
+import java.security.MessageDigest;
+import java.security.NoSuchAlgorithmException;
+import java.text.DecimalFormat;
+import java.util.*;
+import java.util.regex.Matcher;
+import java.util.regex.Pattern;
+
+/**
+ * Utilities for mangling config text, finding md5sums, version numbers in .def files etc.
+ */
+public class ConfigUtils {
+    /* Patterns used for finding ranges in config definitions */
+    private static final Pattern intPattern = Pattern.compile(".*int.*range.*");
+    private static final Pattern doublePattern = Pattern.compile(".*double.*range.*");
+    private static final Pattern spaceBeforeCommaPatter = Pattern.compile("\\s,");
+    public static final String intFormattedMax = new DecimalFormat("#.#").format(0x7fffffff);
+    public static final String intFormattedMin = new DecimalFormat("#.#").format(-0x80000000);
+    public static final String doubleFormattedMax = new DecimalFormat("#.#").format(1e308);
+    public static final String doubleFormattedMin = new DecimalFormat("#.#").format(-1e308);
+
+    /**
+     * Computes Md5 hash of a list of strings. The only change to input lines before
+     * computing md5 is to skip empty lines.
+     *
+     * @param payload a config payload
+     * @return the Md5 hash of the list, with lowercase letters
+     */
+    public static String getMd5(ConfigPayload payload) {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        try {
+            payload.serialize(baos, new JsonFormat(true));
+        } catch (IOException e) {
+            throw new RuntimeException(e);
+        }
+        MessageDigest md5 = getMd5Instance();
+        md5.update(baos.toByteArray());
+        return HexDump.toHexString(md5.digest()).toLowerCase();
+    }
+
+    /**
+     * Computes Md5 hash of a list of strings. The only change to input lines before
+     * computing md5 is to skip empty lines.
+     *
+     * @param lines A list of lines
+     * @return the Md5 hash of the list, with lowercase letters
+     */
+    public static String getMd5(List<String> lines) {
+        StringBuilder sb = new StringBuilder();
+        for (String line : lines) {
+            // Remove empty lines
+            line = line.trim();
+            if (line.length() > 0) {
+                sb.append(line).append("\n");
+            }
+        }
+        MessageDigest md5 = getMd5Instance();
+        md5.update(Utf8.toBytes(sb.toString()));
+        return HexDump.toHexString(md5.digest()).toLowerCase();
+    }
+
+    /**
+     * Computes Md5 hash of a string.
+     *
+     * @param input the input String
+     * @return the Md5 hash of the input, with lowercase letters
+     */
+    public static String getMd5(String input) {
+        MessageDigest md5 = getMd5Instance();
+        md5.update(IOUtils.utf8ByteBuffer(input));
+        return HexDump.toHexString(md5.digest()).toLowerCase();
+    }
+
+    public static String getMd5(Utf8Array input) {
+        MessageDigest md5 = getMd5Instance();
+        md5.update(input.getBytes());
+        return HexDump.toHexString(md5.digest()).toLowerCase();
+    }
+
+    private static MessageDigest getMd5Instance() {
+        try {
+            return MessageDigest.getInstance("MD5");
+        } catch (NoSuchAlgorithmException e) {
+            return null;
+        }
+    }
+
+    /**
+     * Replaces sequences of spaces with 1 space, unless inside quotes. Public for testing;
+     * @param str String to strip spaces from
+     * @return String with spaces stripped
+     */
+    public static String stripSpaces(String str) {
+        StringBuilder ret = new StringBuilder("");
+        boolean inQuotes = false;
+        boolean inSpaceSequence = false;
+        for (char c : str.toCharArray()) {
+            if (Character.isWhitespace(c)) {
+                if (inQuotes) {
+                    ret.append(c);
+                    continue;
+                }
+                if (!inSpaceSequence) {
+                    // start of space sequence
+                    inSpaceSequence=true;
+                    ret.append(" ");
+                }
+            } else {
+                if (inSpaceSequence) {
+                    inSpaceSequence=false;
+                }
+                if (c=='\"') {
+                    inQuotes=!inQuotes;
+                }
+                ret.append(c);
+            }
+        }
+        return ret.toString();
+    }
+
+    /**
+     * Computes Md5 hash of a list of strings with the contents of a def-file.
+     *
+     * Each string is normalized according to the
+     * rules of Vespa config definition files before they are used:
+     * <ol>
+     * <li>Remove trailing space.<li>
+     * <li>Remove comment lines.</li>
+     * <li>Remove trailing comments, and spaces before trailing comments.</li>
+     * <li>Remove empty lines</li>
+     * <li>Remove 'version=&lt;version-number&gt;'</li>
+     * </ol>
+     *
+     * @param lines  A list of lines constituting a def-file
+     * @return the Md5 hash of the list, with lowercase letters
+     */
+    public static String getDefMd5(List<String> lines) {
+        List<String> linesCopy = new ArrayList<>(lines);
+        for (Iterator<String> it=linesCopy.iterator(); it.hasNext(); ) {
+            String line = it.next().trim();
+            if (! line.startsWith("#") && ! line.equals("")) {
+                if (line.startsWith("version")) {
+                    it.remove();
+                }
+                // Quit upon 'version', or first line with real content since 'version' cannot occur after that
+                break;
+            }
+        }
+
+        MessageDigest md5;
+        try {
+            md5 = MessageDigest.getInstance("MD5");
+        } catch (NoSuchAlgorithmException e) {
+            return null;
+        }
+        StringBuilder sb = new StringBuilder();
+        for (String line : linesCopy) {
+            // Normalize line, like it's done in make-config-preproc.pl
+            line = line.trim();
+            // The perl script does stuff like this:
+            Matcher m = intPattern.matcher(line);
+            if (m.matches()) {
+                line = line.replaceFirst("\\[,", "[" + intFormattedMin + ",");
+                line = line.replaceFirst(",\\]", "," + intFormattedMax + "]");
+            }
+            m = doublePattern.matcher(line);
+            if (m.matches()) {
+                line = line.replaceFirst("\\[,", "[" + doubleFormattedMin + ",");
+                line = line.replaceFirst(",\\]", "," + doubleFormattedMax + "]");
+            }
+            if (line.contains("#")) {
+                line = line.substring(0, line.indexOf("#"));
+                line = line.trim();  // Remove space between "real" end of line and a trailing comment
+            }
+            if (line.length() > 0) {
+                line = stripSpaces(line);
+                m  = spaceBeforeCommaPatter.matcher(line);
+                line = m.replaceAll(",");   // Remove space before comma (for enums)
+                sb.append(line).append("\n");
+            }
+        }
+        md5.update(Utf8.toBytes(sb.toString()));
+        return HexDump.toHexString(md5.digest()).toLowerCase();
+    }
+
+    /**
+     * Finds the def version from a reader for a def-file. Returns "" (empty string)
+     * if no version was found.
+     *
+     * @param in A reader to a def-file
+     * @return version of the def-file, or "" (empty string) if no version was found
+     */
+    public static String getDefVersion(Reader in) {
+        return getDefKeyword(in, "version");
+    }
+
+    /**
+     * Finds the def namespace from a reader for a def-file. Returns "" (empty string)
+     * if no namespace was found.
+     *
+     * @param in A reader to a def-file
+     * @return namespace of the def-file, or "" (empty string) if no namespace was found
+     */
+    public static String getDefNamespace(Reader in) {
+        return getDefKeyword(in, "namespace");
+    }
+
+    /**
+     * Finds the value of the keyword in <code>keyword</code> from a reader for a def-file.
+     * Returns "" (empty string) if no value for keyword was found.
+     *
+     * @param in  A reader to a def-file
+     * @return value of keyword, or "" (empty string) if no line matching keyword was found
+     */
+    public static String getDefKeyword(Reader in, String keyword) {
+        if (null == in) {
+            throw new IllegalArgumentException("Null reader.");
+        }
+        LineNumberReader reader;
+        try {
+            if (in instanceof LineNumberReader) {
+                reader = (LineNumberReader) in;
+            } else {
+                reader = new LineNumberReader(in);
+            }
+            String line;
+            while ((line = reader.readLine()) != null) {
+                line = line.trim();
+                if (!line.startsWith("#") && !line.equals("")) {
+                    if (line.startsWith(keyword)) {
+                        String[] v = line.split("=");
+                        return v[1].trim();
+                    }
+                }
+            }
+            reader.close();
+        } catch (IOException e) {
+            throw new RuntimeException("IOException", e);
+        }
+        return "";
+    }
+
+    /**
+     * Finds the name and version from a string with "name,version".
+     * If no name is given, the first part of the tuple will be the empty string
+     * If no version is given, the second part of the tuple will be the empty string
+     *
+     * @param nameCommaVersion A string consisting of "name,version"
+     * @return a Tuple2 with first item being name and second item being version
+     */
+    public static Tuple2<String, String> getNameAndVersionFromString(String nameCommaVersion) {
+        String[] av = nameCommaVersion.split(",");
+        return new Tuple2<>(av[0], av.length >= 2 ? av[1] : "");
+    }
+
+    /**
+     * Finds the name and namespace from a string with "namespace.name".
+     * namespace may contain dots.
+     * If no namespace is given (".name" or just "name"), the second part of the tuple will be the empty string
+     * If no name is given, the first part of the tuple will be the empty string
+     *
+     * @param nameDotNamespace A string consisting of "namespace.name"
+     * @return a Tuple2 with first item being name and second item being namespace
+     */
+    public static Tuple2<String, String> getNameAndNamespaceFromString(String nameDotNamespace) {
+        if (!nameDotNamespace.contains(".")) {
+            return new Tuple2<>(nameDotNamespace, "");
+        }
+        String name = nameDotNamespace.substring(nameDotNamespace.lastIndexOf(".") + 1);
+        String namespace = nameDotNamespace.substring(0, nameDotNamespace.lastIndexOf("."));
+        return new Tuple2<>(name, namespace);
+    }
+
+    /**
+     * Creates a ConfigDefinitionKey based on a string with namespace, name and version
+     * (e.g. Vespa's own config definitions in $VESPA_HOME/var/db/vespa/configserver/serverdb/classes)
+     *
+     * @param input A string consisting of "namespace.name.version"
+     * @return a ConfigDefinitionKey
+     */
+    @SuppressWarnings("deprecation")
+    public static ConfigDefinitionKey getConfigDefinitionKeyFromString(String input) {
+        final String name;
+        final String namespace;
+        if (!input.contains(".")) {
+            name = input;
+            namespace = "";
+        } else if (input.lastIndexOf(".") == input.indexOf(".")) {
+            Tuple2<String, String> tuple = ConfigUtils.getNameAndNamespaceFromString(input);
+            boolean containsVersion = false;
+            for (int i=0; i < tuple.first.length(); i++) {
+               if (Character.isDigit(tuple.first.charAt(i))) {
+                   containsVersion = true;
+                   break;
+               }
+            }
+            if (containsVersion) {
+                name = tuple.second;
+                namespace = "";
+            } else {
+                name = tuple.first;
+                namespace = tuple.second;
+            }
+        } else {
+            Tuple2<String, String> tuple = ConfigUtils.getNameAndNamespaceFromString(input);
+
+            String tempName = tuple.second;
+            tuple = ConfigUtils.getNameAndNamespaceFromString(tempName);
+            name = tuple.first;
+            namespace = tuple.second;
+        }
+        return new ConfigDefinitionKey(name, namespace);
+    }
+
+    /**
+     * Creates a ConfigDefinitionKey from a string for the name of a node in ZooKeeper
+     * that holds a config definition
+     *
+     * @param nodeName name of  a node in ZooKeeper that holds a config definition
+     * @return a ConfigDefinitionKey
+     */
+    @SuppressWarnings("deprecation")
+    public static ConfigDefinitionKey createConfigDefinitionKeyFromZKString(String nodeName) {
+        final String name;
+        final String namespace;
+        if (nodeName.contains(".")) {
+            Tuple2<String, String> tuple = ConfigUtils.getNameAndVersionFromString(nodeName);
+            String tempName = tuple.first; // includes namespace
+            tuple = ConfigUtils.getNameAndNamespaceFromString(tempName);
+            name = tuple.first;
+            namespace = tuple.second;
+        } else {
+            Tuple2<String, String> tuple = ConfigUtils.getNameAndVersionFromString(nodeName);
+            name = tuple.first;
+            namespace = "";
+        }
+        return new ConfigDefinitionKey(name, namespace);
+    }
+
+
+    /**
+     * Creates a ConfigDefinitionKey from a file by reading the file and parsing
+     * contents for namespace. Name and from filename, but the filename may be prefixed
+     * with the namespace (if two def files has the same name for instance).
+     *
+     * @param file a config definition file
+     * @return a ConfigDefinitionKey
+     */
+    public static ConfigDefinitionKey createConfigDefinitionKeyFromDefFile(File file) throws IOException {
+        String[] fileName = file.getName().split("\\.");
+        assert(fileName.length >= 2);
+        String name = fileName[fileName.length - 2];
+        byte[] content = IOUtils.readFileBytes(file);
+
+        return createConfigDefinitionKeyFromDefContent(name, content);
+    }
+
+    /**
+     * Creates a ConfigDefinitionKey from a name and the content of a config definition
+     *
+     * @param name the name of the config definition
+     * @param content content of a config definition
+     * @return a ConfigDefinitionKey
+     */
+    @SuppressWarnings("deprecation")
+    public static ConfigDefinitionKey createConfigDefinitionKeyFromDefContent(String name, byte[] content) {
+        String namespace = ConfigUtils.getDefNamespace(new StringReader(Utf8.toString(content)));
+        if (namespace.isEmpty()) {
+            namespace = CNode.DEFAULT_NAMESPACE;
+        }
+        return new ConfigDefinitionKey(name, namespace);
+    }
+
+
+    /**
+     * Escapes a config value according to the cfg format.
+     * @param input the string to escape
+     * @return the escaped string
+     */
+    public static String escapeConfigFormatValue(String input) {
+        if (input == null) {
+            return "null";
+        }
+        StringBuilder outputBuf = new StringBuilder(input.length());
+        for (int i = 0; i < input.length(); i++) {
+            if (input.charAt(i) == '\\') {
+                outputBuf.append("\\\\");         // backslash is escaped as: \\
+            } else if (input.charAt(i) == '"') {
+                outputBuf.append("\\\"");         // double quote is escaped as: \"
+            } else if (input.charAt(i) == '\n') {
+                outputBuf.append("\\n");          // newline is escaped as: \n
+            } else if (input.charAt(i) == 0) {
+                // XXX null byte is probably not a good idea anyway
+                System.err.println("WARNING: null byte in config value");
+                outputBuf.append("\\x00");
+            } else {
+                // all other characters are output as-is
+                outputBuf.append(input.charAt(i));
+            }
+        }
+        return outputBuf.toString();
+    }
+
+
+    public static String getDefMd5FromRequest(String defMd5, List<String> defContent) {
+        if ((defMd5 == null || defMd5.isEmpty()) && defContent != null) {
+            return ConfigUtils.getDefMd5(defContent);
+        } else {
+            return defMd5;
+        }
+    }
+
+    public static String getCanonicalHostName() {
+        try {
+            return com.yahoo.net.LinuxInetAddress.getLocalHost().getCanonicalHostName();
+        } catch (UnknownHostException e) {
+            throw new RuntimeException(e);
+        }
+    }
+
+    /**
+     * Loop through values and return the first one that is set and non-empty.
+     *
+     * @param defaultValue The default value to use if no environment variables are set.
+     * @param envVars one or more environment variable strings
+     * @return a String with the value of the environment variable
+     */
+    public static String getEnvValue(String defaultValue, String ... envVars) {
+        String value = null;
+        for (String envVar : envVars) {
+            if (value == null || value.isEmpty()) {
+                value = envVar;
+            }
+        }
+        return (value == null || value.isEmpty()) ? defaultValue : value;
+    }
+
+    public static boolean isGenerationNewer(long newGen, long oldGen) {
+        return (oldGen < newGen) || (newGen == 0);
+    }
+}
diff --git a/config/src/main/java/com/yahoo/vespa/config/util/package-info.java b/config/src/main/java/com/yahoo/vespa/config/util/package-info.java
new file mode 100644
index 00000000000..30f76c1ecbf
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/util/package-info.java
@@ -0,0 +1,5 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+@ExportPackage
+package com.yahoo.vespa.config.util;
+
+import com.yahoo.osgi.annotation.ExportPackage;
diff --git a/config/src/main/java/com/yahoo/vespa/config/xml/.gitignore b/config/src/main/java/com/yahoo/vespa/config/xml/.gitignore
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/config/xml/.gitignore
diff --git a/config/src/main/java/com/yahoo/vespa/zookeeper/.gitignore b/config/src/main/java/com/yahoo/vespa/zookeeper/.gitignore
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/main/java/com/yahoo/vespa/zookeeper/.gitignore
diff --git a/config/src/test/java/com/yahoo/config/subscription/AppService.java b/config/src/test/java/com/yahoo/config/subscription/AppService.java
new file mode 100644
index 00000000000..1f0fc43ed4e
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/AppService.java
@@ -0,0 +1,76 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.foo.AppConfig;
+import com.yahoo.vespa.config.TimingValues;
+
+/**
+ * @author <a href="musum@yahoo-inc.com">Harald Musum</a>
+ *
+ * Application that subscribes to config defined in app.def and
+ * generated code in AppConfig.java.
+ */
+public class AppService {
+    protected int timesConfigured = 0;
+
+    protected AppConfig config = null;
+    private final ConfigSubscriber subscriber;
+    protected final String configId;
+
+    final Thread configThread;
+    boolean stopThread = false;
+
+    public AppService(String configId, ConfigSourceSet csource) {
+        this(configId, csource, null);
+    }
+
+    public int timesConfigured() { return timesConfigured; }
+
+    public AppService(String configId, ConfigSourceSet csource, TimingValues timingValues) {
+        if (csource == null) throw new IllegalArgumentException("Config source cannot be null");
+        this.configId = configId;
+        subscriber = new ConfigSubscriber(csource);
+        ConfigHandle<AppConfig> temp;
+        if (timingValues == null) {
+            temp = subscriber.subscribe(AppConfig.class, configId);
+        } else {
+            temp = subscriber.subscribe(AppConfig.class, configId, csource, timingValues);
+        }
+        final ConfigHandle<AppConfig> handle = temp;
+        configThread = new Thread(new Runnable() {
+            @Override
+            public void run() {
+                while (!stopThread) {
+                    boolean changed = subscriber.nextConfig(500);
+                    if (changed) {
+                        configure(handle.getConfig());
+                        timesConfigured++;
+                    }
+                }
+            }
+        });
+        subscriber.nextConfig(5000);
+        timesConfigured++;
+        configure(handle.getConfig());
+        configThread.setDaemon(true);
+        configThread.start();
+    }
+
+    public void configure(AppConfig config) {
+        this.config = config;
+    }
+
+    public void cancelSubscription() {
+        subscriber.close();
+        stopThread = true;
+    }
+
+    public AppConfig getConfig() {
+        return config;
+    }
+
+    public boolean isConfigured() {
+        return (timesConfigured > 0);
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/BasicTest.java b/config/src/test/java/com/yahoo/config/subscription/BasicTest.java
new file mode 100644
index 00000000000..0d59e9e7ee7
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/BasicTest.java
@@ -0,0 +1,31 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import static org.junit.Assert.*;
+import static org.hamcrest.CoreMatchers.is;
+
+import com.yahoo.foo.AppConfig;
+
+import org.junit.Test;
+
+
+public class BasicTest {
+
+    @Test
+    public void testSubBasic() {
+        ConfigSubscriber s = new ConfigSubscriber();
+        ConfigHandle<AppConfig> h = s.subscribe(AppConfig.class, "raw:times 0");
+        s.nextConfig(0);
+        AppConfig c = h.getConfig();
+        assertThat(c.times(), is(0));
+    }
+
+    @Test
+    public void testSubBasicGeneration() {
+        ConfigSubscriber s = new ConfigSubscriber();
+        ConfigHandle<AppConfig> h = s.subscribe(AppConfig.class, "raw:times 2");
+        s.nextGeneration(0);
+        AppConfig c = h.getConfig();
+        assertThat(c.times(), is(2));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/CfgConfigPayloadBuilderTest.java b/config/src/test/java/com/yahoo/config/subscription/CfgConfigPayloadBuilderTest.java
new file mode 100644
index 00000000000..55d1e5774a5
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/CfgConfigPayloadBuilderTest.java
@@ -0,0 +1,315 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.foo.FunctionTestConfig;
+import com.yahoo.config.InnerNode;
+import com.yahoo.foo.SimpletypesConfig;
+import com.yahoo.vespa.config.ConfigPayload;
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.List;
+
+import static com.yahoo.config.subscription.util.JsonHelper.assertJsonEquals;
+import static com.yahoo.config.subscription.util.JsonHelper.inputJson;
+import static org.junit.Assert.assertEquals;
+
+/**
+ * @author <a href="mailto:musum@yahoo-inc.com">Harald Musum</a>
+ * @author Vegard Sjonfjell
+ * @since 5.1
+ */
+public class CfgConfigPayloadBuilderTest {
+
+    @Test
+    public void createConfigPayload() {
+        final FunctionTestConfig config = ConfigInstancePayloadTest.createVariableAccessConfigWithBuilder();
+
+        final String expectedJson = inputJson(
+                "{",
+                "    'double_val': '41.23',",
+                "    'refarr': [",
+                "        ':parent:',",
+                "        ':parent',",
+                "        'parent:'",
+                "    ],",
+                "    'pathVal': 'src/test/resources/configs/def-files/function-test.def',",
+                "    'string_val': 'foo',",
+                "    'myStructMap': {",
+                "        'one': {",
+                "            'myString': 'bull',",
+                "            'anotherMap': {",
+                "                'anotherOne': {",
+                "                    'anInt': '3',",
+                "                    'anIntDef': '4'",
+                "                }",
+                "            },",
+                "            'myInt': '1',",
+                "            'myStringDef': 'bear',",
+                "            'myIntDef': '2'",
+                "        }",
+                "    },",
+                "    'boolarr': [",
+                "        'false'",
+                "    ],",
+                "    'intMap': {",
+                "        'dotted.key': '3',",
+                "        'spaced key': '4',",
+                "        'two': '2',",
+                "        'one': '1'",
+                "    },",
+                "    'int_val': '5',",
+                "    'stringarr': [",
+                "        'bar'",
+                "    ],",
+                "    'enum_val': 'FOOBAR',",
+                "    'myarray': [",
+                "        {",
+                "            'anotherarray': [",
+                "                {",
+                "                    'foo': '7'",
+                "                }",
+                "            ],",
+                "            'intval': '-5',",
+                "            'fileVal': 'file0',",
+                "            'refval': ':parent:',",
+                "            'myStruct': {",
+                "                'a': '1',",
+                "                'b': '2'",
+                "            },",
+                "            'stringval': [",
+                "                'baah',",
+                "                'yikes'",
+                "            ],",
+                "            'enumval': 'INNER'",
+                "        },",
+                "        {",
+                "            'anotherarray': [",
+                "                {",
+                "                    'foo': '2'",
+                "                }",
+                "            ],",
+                "            'intval': '5',",
+                "            'fileVal': 'file1',",
+                "            'refval': ':parent:',",
+                "            'myStruct': {",
+                "                'a': '-1',",
+                "                'b': '-2'",
+                "            },",
+                "            'enumval': 'INNER'",
+                "        }",
+                "    ],",
+                "    'fileArr': [",
+                "        'bin'",
+                "    ],",
+                "    'enumwithdef': 'BAR2',",
+                "    'bool_with_def': 'true',",
+                "    'enumarr': [",
+                "        'VALUES'",
+                "    ],",
+                "    'pathMap': {",
+                "        'one': 'pom.xml'",
+                "    },",
+                "    'long_with_def': '-9876543210',",
+                "    'double_with_def': '-12.0',",
+                "    'stringMap': {",
+                "        'double spaced key': 'third',",
+                "        'double.dotted.key': 'second',",
+                "        'one': 'first'",
+                "    },",
+                "    'refwithdef': ':parent:',",
+                "    'stringwithdef': 'bar and foo',",
+                "    'doublearr': [",
+                "        '2344.0',",
+                "        '123.0'",
+                "    ],",
+                "    'int_with_def': '-14',",
+                "    'pathArr': [",
+                "        'pom.xml'",
+                "    ],",
+                "    'rootStruct': {",
+                "        'innerArr': [",
+                "            {",
+                "                'stringVal': 'deep',",
+                "                'boolVal': 'true'",
+                "            },",
+                "            {",
+                "                'stringVal': 'blue a=\\\'escaped\\\'',",
+                "                'boolVal': 'false'",
+                "            }",
+                "        ],",
+                "        'inner0': {",
+                "            'index': '11',",
+                "            'name': 'inner0'",
+                "        },",
+                "        'inner1': {",
+                "            'index': '12',",
+                "            'name': 'inner1'",
+                "        }",
+                "    },",
+                "    'fileVal': 'etc',",
+                "    'refval': ':parent:',",
+                "    'onechoice': 'ONLYFOO',",
+                "    'bool_val': 'false',",
+                "    'longarr': [",
+                "        '9223372036854775807',",
+                "        '-9223372036854775808'",
+                "    ],",
+                "    'basicStruct': {",
+                "        'intArr': [",
+                "            '310',",
+                "            '311'",
+                "        ],",
+                "        'foo': 'basicFoo',",
+                "        'bar': '3'",
+                "    },",
+                "    'long_val': '12345678901'",
+                "}"
+        );
+
+        CfgConfigPayloadBuilderTest.assertDeserializedConfigEqualsJson(config, expectedJson);
+    }
+
+    // FIXME: We need to define the behavior here.
+    @Test
+    public void test_empty_struct_arrays() {
+        assertDeserializedConfigEqualsJson("myArray[1]", inputJson("{}"));
+    }
+
+    @Test
+    public void test_escaped_string() {
+        assertDeserializedConfigEqualsJson("a b=\"escaped\"",
+                inputJson(
+                        "{",
+                        " 'a': 'b=\\\'escaped\\\''",
+                        "}"
+                )
+        );
+    }
+
+    @Test
+    public void test_empty_payload() {
+        assertDeserializedConfigEqualsJson("", inputJson("{}"));
+    }
+
+    @Test
+    public void test_leading_whitespace() {
+        assertDeserializedConfigEqualsJson(" a 0",
+                inputJson(
+                        "{",
+                        "    'a': '0'",
+                        "}")
+        );
+    }
+
+    @Test
+    public void test_leading_and_trailing_whitespace_string() {
+        assertDeserializedConfigEqualsJson(
+                "a \" foo \"",
+                inputJson(
+                        "{",
+                        "    'a': ' foo '",
+                        "}"));
+    }
+
+    @Test
+    public void test_config_with_comments() {
+        CfgConfigPayloadBuilderTest.assertDeserializedConfigEqualsJson(
+                Arrays.asList(
+                        "fielda b\n",
+                        "#fielda c\n",
+                        "#fieldb c\n",
+                        "# just a comment"),
+                inputJson(
+                        "{",
+                        "    'fielda': 'b'",
+                        "}")
+        );
+    }
+
+    @Test
+    public void testConvertingMaps() {
+        List<String> payload = Arrays.asList(
+                "intmap{\"foo\"} 1337",
+                "complexmap{\"key\"}.foo 1337",
+                "nestedmap{\"key1\"}.foo{\"key2\"}.bar 1337"
+        );
+
+        final String expectedJson = inputJson(
+                "{",
+                "    'nestedmap': {",
+                "        'key1': {",
+                "            'foo': {",
+                "                'key2': {",
+                "                    'bar': '1337'",
+                "                }",
+                "            }",
+                "        }",
+                "    },",
+                "    'intmap': {",
+                "        'foo': '1337'",
+                "    },",
+                "    'complexmap': {",
+                "        'key': {",
+                "            'foo': '1337'",
+                "        }",
+                "    }",
+                "}"
+        );
+
+        CfgConfigPayloadBuilderTest.assertDeserializedConfigEqualsJson(payload, expectedJson);
+    }
+
+    @Test
+    public void createConfigPayloadUtf8() {
+        SimpletypesConfig.Builder builder = new SimpletypesConfig.Builder().stringval("Hei \u00E6\u00F8\u00E5 \uBC14\uB451 \u00C6\u00D8\u00C5 hallo");
+        SimpletypesConfig config = new SimpletypesConfig(builder);
+
+        String expectedJson = inputJson(
+                "{",
+                "    'longval': '0',",
+                "    'intval': '0',",
+                "    'stringval': 'Hei \u00e6\u00f8\u00e5 \ubc14\ub451 \u00c6\u00d8\u00c5 hallo',",
+                "    'boolval': 'false',",
+                "    'doubleval': '0.0',",
+                "    'enumval': 'VAL1'",
+                "}"
+        );
+
+        CfgConfigPayloadBuilderTest.assertDeserializedConfigEqualsJson(config, expectedJson);
+    }
+
+    @Test
+    public void testLineParsing() {
+        CfgConfigPayloadBuilder builder = new CfgConfigPayloadBuilder();
+        assertEquals(builder.parseFieldAndValue("foo bar").getFirst(), "foo");
+        assertEquals(builder.parseFieldAndValue("foo bar").getSecond(), "bar");
+        assertEquals(builder.parseFieldAndValue("foo.bar.baz{my key} baR").getFirst(), "foo.bar.baz{my key}");
+        assertEquals(builder.parseFieldAndValue("foo.bar.baz{my key} baR").getSecond(), "baR");
+        assertEquals(builder.parseFieldAndValue("foo.bar.baz{my.key} baRR").getFirst(), "foo.bar.baz{my.key}");
+        assertEquals(builder.parseFieldAndValue("foo.bar.baz{my.key} baRR").getSecond(), "baRR");
+        assertEquals(builder.parseFieldAndValue("foo.bar.baz{my key.dotted}.biz baRO").getFirst(), "foo.bar.baz{my key.dotted}.biz");
+        assertEquals(builder.parseFieldAndValue("foo.bar.baz{my key.dotted}.biz baRO").getSecond(), "baRO");
+
+        assertEquals(builder.parseFieldList("foo.bar.baz").get(0), "foo");
+        assertEquals(builder.parseFieldList("foo.bar.baz").get(1), "bar");
+        assertEquals(builder.parseFieldList("foo.bar.baz").get(2), "baz");
+        assertEquals(builder.parseFieldList("foo.bar{f.b}.baz{f.h h}").get(0), "foo");
+        assertEquals(builder.parseFieldList("foo.bar{f.b}.baz{f.h h}").get(1), "bar{f.b}");
+        assertEquals(builder.parseFieldList("foo.bar{f.b}.baz{f.h h}").get(2), "baz{f.h h}");
+    }
+
+    private static void assertDeserializedConfigEqualsJson(InnerNode config, String expectedJson) {
+        assertDeserializedConfigEqualsJson(ConfigInstance.serialize(config), expectedJson);
+    }
+
+    private static void assertDeserializedConfigEqualsJson(String serializedConfig, String expectedJson) {
+        assertDeserializedConfigEqualsJson(Arrays.asList(serializedConfig), expectedJson);
+    }
+
+    private static void assertDeserializedConfigEqualsJson(List<String> inputConfig, String expectedJson) {
+        ConfigPayload payload = new CfgConfigPayloadBuilder().deserialize(inputConfig);
+        assertJsonEquals(payload.toString(), expectedJson);
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/ConfigApiTest.java b/config/src/test/java/com/yahoo/config/subscription/ConfigApiTest.java
new file mode 100755
index 00000000000..608bf2e12b0
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/ConfigApiTest.java
@@ -0,0 +1,60 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.foo.*;
+
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+import static org.hamcrest.CoreMatchers.is;
+
+/**
+ * Tests ConfigSubscriber API, and the ConfigHandle class.
+ *
+ * @author <a href="gv@yahoo-inc.com">Harald Musum</a>
+ * @since 5.1
+ */
+public class ConfigApiTest {
+    private static final String CONFIG_ID = "raw:" + "times 1\n";
+
+    @Test
+    public void testConfigSubscriber() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        ConfigHandle<AppConfig> h = subscriber.subscribe(AppConfig.class, CONFIG_ID);
+        assertNotNull(h);
+        subscriber.nextConfig();
+        assertNotNull(h.getConfig());
+        assertEquals(AppConfig.CONFIG_DEF_NAME, ConfigInstance.getDefName(h.getConfig().getClass()));
+        assertThat(h.isChanged(), is(true));
+        assertTrue(h.toString().startsWith("Handle changed: true\nSub:\n"));
+        subscriber.close();
+        assertThat(subscriber.state(), is(ConfigSubscriber.State.CLOSED));
+    }
+
+    /**
+     * Verifies that we get an exception when trying to subscribe after close() has been called
+     * for a ConfigSubscriber
+     */
+    @Test(expected = IllegalStateException.class)
+    public void testSubscribeAfterClose() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        subscriber.subscribe(AppConfig.class, CONFIG_ID);
+        subscriber.nextConfig();
+        subscriber.close();
+        subscriber.subscribe(AppConfig.class, CONFIG_ID);
+    }
+
+    /**
+     * Verifies that it is not possible to to subscribe again after calling nextConfig()
+     */
+    @Test(expected = IllegalStateException.class)
+    public void testSubscribeAfterNextConfig() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        subscriber.subscribe(AppConfig.class, CONFIG_ID);
+        subscriber.nextConfig();
+        subscriber.subscribe(AppConfig.class, CONFIG_ID);
+        subscriber.close();
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/ConfigGetterTest.java b/config/src/test/java/com/yahoo/config/subscription/ConfigGetterTest.java
new file mode 100644
index 00000000000..bb5e712fe3a
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/ConfigGetterTest.java
@@ -0,0 +1,111 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.foo.AppConfig;
+
+import org.junit.Test;
+
+import java.io.File;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * Unit test for the {@link ConfigGetter}.
+ *
+ * @author gjoranv
+ */
+public class ConfigGetterTest {
+    private ConfigSourceSet sourceSet = new ConfigSourceSet("config-getter-test");
+
+    @Test
+    public void testGetConfig() {
+        int times = 11;
+        String message = "testGetConfig";
+        String a0 = "a0";
+        String configId = "raw:times " + times + "\nmessage " + message + "\na[1]\na[0].name " + a0;
+
+        ConfigGetter<AppConfig> getter = new ConfigGetter<>(AppConfig.class);
+        AppConfig config = getter.getConfig(configId);
+        assertThat(config.times(), is(times));
+        assertThat(config.message(), is(message));
+        assertThat(config.a().size(), is(1));
+        assertThat(config.a(0).name(), is(a0));
+
+        AppService service = new AppService(configId, sourceSet);
+        AppConfig serviceConfig = service.getConfig();
+        assertTrue(service.isConfigured());
+        assertThat(config, is(serviceConfig));
+    }
+
+@Test
+    public void testGetFromRawSource() {
+        ConfigGetter<AppConfig> getter = new ConfigGetter<>(new RawSource("message \"one\""), AppConfig.class);
+        AppConfig config = getter.getConfig("test");
+        assertThat(config.message(), is("one"));
+    }
+
+    @Test
+    public void testGetTwice() {
+        ConfigGetter<AppConfig> getter = new ConfigGetter<>(AppConfig.class);
+        AppConfig config = getter.getConfig("raw:message \"one\"");
+        assertThat(config.message(), is("one"));
+        config = getter.getConfig("raw:message \"two\"");
+        assertThat(config.message(), is("two"));
+    }
+
+    @Test
+    public void testGetFromFile() {
+        ConfigGetter<AppConfig> getter = new ConfigGetter<>(AppConfig.class);
+        AppConfig config = getter.getConfig("file:src/test/resources/configs/foo/app.cfg");
+        verifyFooValues(config);
+    }
+
+     @Test
+    public void testGetFromFileSource() {
+        ConfigGetter<AppConfig> getter = new ConfigGetter<>(new FileSource(new File("src/test/resources/configs/foo/app.cfg")), AppConfig.class);
+        AppConfig config = getter.getConfig("test");
+        verifyFooValues(config);
+    }
+
+    @Test
+    public void testGetFromDir() {
+        ConfigGetter<AppConfig> getter = new ConfigGetter<>(AppConfig.class);
+        AppConfig config = getter.getConfig("dir:src/test/resources/configs/foo/");
+        verifyFooValues(config);
+    }
+
+    @Test
+    public void testGetFromDirSource() {
+        AppConfig config = ConfigGetter.getConfig(AppConfig.class, "test", new DirSource(new File("src/test/resources/configs/foo/")));
+        verifyFooValues(config);
+    }
+
+    private void verifyFooValues(AppConfig config) {
+        assertThat(config.message(), is("msg1"));
+        assertThat(config.times(), is(3));
+        assertThat(config.a(0).name(), is("a0"));
+        assertThat(config.a(1).name(), is("a1"));
+        assertThat(config.a(2).name(), is("a2"));
+    }
+
+    @Test
+    public void testsStaticGetConfig() {
+        int times = 11;
+        String message = "testGetConfig";
+        String a0 = "a0";
+        String configId = "raw:times " + times + "\nmessage " + message + "\na[1]\na[0].name " + a0;
+
+        AppConfig config = ConfigGetter.getConfig(AppConfig.class, configId);
+        assertThat(config.times(), is(times));
+        assertThat(config.message(), is(message));
+        assertThat(config.a().size(), is(1));
+        assertThat(config.a(0).name(), is(a0));
+
+        AppService service = new AppService(configId, sourceSet);
+        AppConfig serviceConfig = service.getConfig();
+        assertTrue(service.isConfigured());
+        assertThat(config, is(serviceConfig));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/ConfigInstancePayloadTest.java b/config/src/test/java/com/yahoo/config/subscription/ConfigInstancePayloadTest.java
new file mode 100644
index 00000000000..d7a88d591e4
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/ConfigInstancePayloadTest.java
@@ -0,0 +1,188 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.FileReference;
+import com.yahoo.foo.FunctionTestConfig;
+import com.yahoo.foo.MaptypesConfig;
+import com.yahoo.slime.Slime;
+import com.yahoo.vespa.config.ConfigPayload;
+import com.yahoo.vespa.config.ConfigTransformer;
+import org.junit.Test;
+
+import java.io.File;
+import java.util.Arrays;
+import java.util.List;
+
+import static com.yahoo.foo.FunctionTestConfig.*;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.fail;
+
+/**
+ * @author gjoranv
+ * @since 5.1.6
+ */
+public class ConfigInstancePayloadTest {
+
+    static FunctionTestConfig createVariableAccessConfigWithBuilder() {
+        return new FunctionTestConfig(createVariableAccessBuilder());
+    }
+
+    static FunctionTestConfig.Builder createVariableAccessBuilder() {
+        return new FunctionTestConfig.Builder().
+                bool_val(false).
+                bool_with_def(true).
+                int_val(5).
+                int_with_def(-14).
+                long_val(12345678901L).
+                long_with_def(-9876543210L).
+                double_val(41.23).
+                double_with_def(-12).
+                string_val("foo").
+                stringwithdef("bar and foo").
+                enum_val(Enum_val.FOOBAR).
+                enumwithdef(Enumwithdef.BAR2).
+                refval(":parent:").
+                refwithdef(":parent:").
+                fileVal("etc").
+                pathVal(FileReference.mockFileReferenceForUnitTesting(new File("src/test/resources/configs/def-files/function-test.def"))).
+                boolarr(false).
+                longarr(9223372036854775807L).
+                longarr(-9223372036854775808L).
+                doublearr(2344.0).
+                doublearr(123.0).
+                stringarr("bar").
+                enumarr(Enumarr.VALUES).
+                refarr(Arrays.asList(":parent:", ":parent", "parent:")).  // test collection based setter
+                fileArr("bin").
+                pathArr(FileReference.mockFileReferenceForUnitTesting(new File("pom.xml"))).
+                intMap("one", 1).
+                intMap("two", 2).
+                intMap("dotted.key", 3).
+                intMap("spaced key", 4).
+                stringMap("one", "first").
+                stringMap("double.dotted.key", "second").
+                stringMap("double spaced key", "third").
+                pathMap("one", FileReference.mockFileReferenceForUnitTesting(new File("pom.xml"))).
+                basicStruct(new BasicStruct.Builder().
+                        foo("basicFoo").
+                        bar(3).
+                        intArr(310).intArr(311)).
+
+                rootStruct(new RootStruct.Builder().
+                        inner0(new RootStruct.Inner0.Builder().
+                                index(11)).
+                        inner1(new RootStruct.Inner1.Builder().
+                                index(12)).
+                        innerArr(new RootStruct.InnerArr.Builder().
+                                boolVal(true).
+                                stringVal("deep")).
+                        innerArr(new RootStruct.InnerArr.Builder().
+                                boolVal(false).
+                                stringVal("blue a=\"escaped\""))).
+
+                myarray(new Myarray.Builder().
+                        intval(-5).
+                        stringval("baah").
+                        stringval("yikes").
+                        enumval(Myarray.Enumval.INNER).
+                        refval(":parent:").
+                        fileVal("file0").
+                        anotherarray(new Myarray.Anotherarray.Builder().
+                                foo(7)).
+                        myStruct(new Myarray.MyStruct.Builder().
+                                a(1).
+                                b(2))).
+
+                myarray(new Myarray.Builder().
+                        intval(5).
+                        enumval(Myarray.Enumval.INNER).
+                        refval(":parent:").
+                        fileVal("file1").
+                        anotherarray(new Myarray.Anotherarray.Builder().
+                                foo(1).
+                                foo(2)).
+                        myStruct(new Myarray.MyStruct.Builder().
+                                a(-1).
+                                b(-2))).
+
+                myStructMap("one", new MyStructMap.Builder().
+                        myInt(1).
+                        myString("bull").
+                        myIntDef(2).
+                        myStringDef("bear").
+                        anotherMap("anotherOne", new MyStructMap.AnotherMap.Builder().
+                                anInt(3).
+                                anIntDef(4)));
+    }
+
+    @Test
+    public void config_builder_can_be_created_from_generic_payload() {
+        FunctionTestConfig config = createVariableAccessConfigWithBuilder();
+        ConfigPayload payload = new CfgConfigPayloadBuilder().deserialize(ConfigInstance.serialize(config));
+        assertFunctionTestPayload(config, payload);
+    }
+
+    @Test
+    public void config_builder_can_be_created_from_typed_payload() {
+        FunctionTestConfig config = createVariableAccessConfigWithBuilder();
+        Slime slime = new Slime();
+        ConfigInstanceSerializer serializer = new ConfigInstanceSerializer(slime);
+        ConfigInstance.serialize(config, serializer);
+        assertFunctionTestPayload(config, new ConfigPayload(slime));
+    }
+
+    private void assertFunctionTestPayload(FunctionTestConfig expected, ConfigPayload payload) {
+        try {
+            System.out.println(payload.toString(false));
+            FunctionTestConfig config2 = new FunctionTestConfig((FunctionTestConfig.Builder)new ConfigTransformer<>(FunctionTestConfig.class).toConfigBuilder(payload));
+            assertThat(config2, is(expected));
+            assertThat(ConfigInstance.serialize(config2), is(ConfigInstance.serialize(expected)));
+        } catch (Exception e) {
+            e.printStackTrace();
+            fail();
+        }
+    }
+
+    @Test
+    public void function_test_payload_is_correctly_deserialized() {
+        FunctionTestConfig orig = createVariableAccessConfigWithBuilder();
+        List<String> lines = ConfigInstance.serialize(orig);
+        ConfigPayload payload = new CfgConfigPayloadBuilder().deserialize(lines);
+        FunctionTestConfig config = ConfigInstanceUtil.getNewInstance(FunctionTestConfig.class, "foo", payload);
+        FunctionTest.assertVariableAccessValues(config, "foo");
+    }
+
+    @Test
+    public void map_types_are_correctly_deserialized() {
+        MaptypesConfig orig = createMapTypesConfig();
+        List<String> lines = ConfigInstance.serialize(orig);
+        ConfigPayload payload = new CfgConfigPayloadBuilder().deserialize(lines);
+        System.out.println(payload.toString());
+        MaptypesConfig config = ConfigInstanceUtil.getNewInstance(MaptypesConfig.class, "foo", payload);
+        System.out.println(config);
+        assertThat(config.intmap().size(), is(1));
+        assertThat(config.intmap("foo"), is(1337));
+        assertNotNull(config.innermap("bar"));
+        assertThat(config.innermap("bar").foo(), is(93));
+        assertThat(config.nestedmap().size(), is(1));
+        assertNotNull(config.nestedmap("baz"));
+        assertThat(config.nestedmap("baz").inner("foo"), is(1));
+        assertThat(config.nestedmap("baz").inner("bar"), is(2));
+    }
+
+    private MaptypesConfig createMapTypesConfig() {
+        MaptypesConfig.Builder builder = new MaptypesConfig.Builder();
+        builder.intmap("foo", 1337);
+        MaptypesConfig.Innermap.Builder inner = new MaptypesConfig.Innermap.Builder();
+        inner.foo(93);
+        builder.innermap("bar", inner);
+        MaptypesConfig.Nestedmap.Builder n1 = new MaptypesConfig.Nestedmap.Builder();
+        n1.inner("foo", 1);
+        n1.inner("bar", 2);
+        builder.nestedmap("baz", n1);
+        return new MaptypesConfig(builder);
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/ConfigInstanceSerializationTest.java b/config/src/test/java/com/yahoo/config/subscription/ConfigInstanceSerializationTest.java
new file mode 100644
index 00000000000..97e954b95fb
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/ConfigInstanceSerializationTest.java
@@ -0,0 +1,257 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.foo.FunctionTestConfig;
+import com.yahoo.config.codegen.DefLine;
+import com.yahoo.vespa.config.ConfigPayload;
+import org.junit.Test;
+
+import java.util.List;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author gjoranv
+ * @author vegardh
+ */
+public class ConfigInstanceSerializationTest {
+
+    private DefLine.Type stringType = new DefLine.Type("string");
+    private DefLine.Type intType = new DefLine.Type("int");
+    private DefLine.Type longType = new DefLine.Type("long");
+    private DefLine.Type boolType = new DefLine.Type("bool");
+    private DefLine.Type doubleType = new DefLine.Type("double");
+    private DefLine.Type fileType = new DefLine.Type("file");
+    private DefLine.Type refType = new DefLine.Type("reference");
+
+    @Test
+    public void require_symmetrical_serialization_and_deserialization_with_builder() {
+        FunctionTestConfig config = ConfigInstancePayloadTest.createVariableAccessConfigWithBuilder();
+
+        // NOTE: configId must be ':parent:' because the library replaces ReferenceNodes with that value with
+        //        the instance's configId. (And the config used here contains such nodes.)
+        List<String> lines = ConfigInstance.serialize(config);
+        ConfigPayload payload = new CfgConfigPayloadBuilder().deserialize(lines);
+
+        FunctionTestConfig config2 = ConfigInstanceUtil.getNewInstance(FunctionTestConfig.class, ":parent:", payload);
+        assertThat(config, is(config2));
+        assertThat(ConfigInstance.serialize(config), is(ConfigInstance.serialize(config2)));
+    }
+
+/** Looks like everything in the commented block tests unused api's.. remove?
+
+    @Test
+    public void testSerializeAgainstConfigDefinitionAllowNothing() {
+        FunctionTestConfig config = ConfigInstancePayloadTest.createVariableAccessConfigWithBuilder();
+        InnerCNode def = new InnerCNode("function-test");
+        List<String> payload = Validator.serialize(config, def);
+        Assert.assertEquals(payload.size(), 0);
+    }
+
+    @Test
+    public void testSerializeAgainstConfigDefinitionAllLeaves() {
+        FunctionTestConfig config = ConfigInstancePayloadTest.createVariableAccessConfigWithBuilder();
+        InnerCNode def = new InnerCNode("function-test");
+        def.children().put("bool_val", LeafCNode.newInstance(boolType, def, "bool_val"));
+        def.children().put("bool_with_def", LeafCNode.newInstance(boolType, def, "bool_with_def"));
+        def.children().put("int_val", LeafCNode.newInstance(intType, def, "int_val"));
+        def.children().put("int_with_def", LeafCNode.newInstance(intType, def, "int_with_def"));
+        def.children().put("long_val", LeafCNode.newInstance(longType, def, "long_val"));
+        def.children().put("long_with_def", LeafCNode.newInstance(longType, def, "long_with_def"));
+        def.children().put("double_val", LeafCNode.newInstance(doubleType, def, "double_val"));
+        def.children().put("double_with_def", LeafCNode.newInstance(doubleType, def, "double_with_def"));
+        def.children().put("string_val", LeafCNode.newInstance(stringType, def, "string_val"));
+        def.children().put("stringwithdef", LeafCNode.newInstance(stringType, def, "stringwithdef"));
+        def.children().put("enum_val", LeafCNode.newInstance(enumType(new String[]{"FOO", "BAR", "FOOBAR"}), def, "enum_val"));
+        def.children().put("enumwithdef", LeafCNode.newInstance(enumType(new String[]{"FOO2", "BAR2", "FOOBAR2"}), def, "enumwithdef", "BAR2"));
+        def.children().put("refval", LeafCNode.newInstance(refType, def, "refval"));
+        def.children().put("refwithdef", LeafCNode.newInstance(refType, def, "refwithdef"));
+        def.children().put("fileVal", LeafCNode.newInstance(fileType, def, "fileVal"));
+
+        List<String> payload = Validator.serialize(config, def);
+        String plString = payload.toString();
+        Assert.assertTrue(plString.matches(".*bool_val false.*"));
+        Assert.assertTrue(plString.matches(".*bool_with_def true.*"));
+        Assert.assertTrue(plString.matches(".*int_val 5.*"));
+        Assert.assertTrue(plString.matches(".*int_with_def -14.*"));
+        Assert.assertTrue(plString.matches(".*long_val 12345678901.*"));
+        Assert.assertTrue(plString.matches(".*long_with_def -9876543210.*"));
+        Assert.assertTrue(plString.matches(".*double_val 41\\.23.*"));
+        Assert.assertTrue(plString.matches(".*double_with_def -12.*"));
+        Assert.assertTrue(plString.matches(".*string_val \"foo\".*"));
+        Assert.assertTrue(plString.matches(".*stringwithdef \"bar and foo\".*"));
+        Assert.assertTrue(plString.matches(".*enum_val FOOBAR.*"));
+        Assert.assertTrue(plString.matches(".*enumwithdef BAR2.*"));
+        Assert.assertTrue(plString.matches(".*refval \\:parent\\:.*"));
+        Assert.assertTrue(plString.matches(".*refwithdef \\:parent\\:.*"));
+        Assert.assertTrue(plString.matches(".*fileVal \"etc\".*"));
+    }
+
+    @Test
+    public void testSerializeAgainstConfigDefinitionSomeLeaves() {
+        FunctionTestConfig config = ConfigInstancePayloadTest.createVariableAccessConfigWithBuilder();
+        InnerCNode def = new InnerCNode("function-test");
+        def.children().put("stringwithdef", LeafCNode.newInstance(stringType, def, "stringwithdef"));
+        def.children().put("long_with_def", LeafCNode.newInstance(longType, def, "long_with_def"));
+        // But not double_with_def etc, and no structs/arrays
+        List<String> payload = Validator.serialize(config, def);
+        String plString = payload.toString();
+        Assert.assertTrue(plString.matches(".*long_with_def \\-9876543210.*"));
+        Assert.assertTrue(plString.matches(".*stringwithdef \"bar and foo\".*"));
+        Assert.assertFalse(plString.matches(".*double_with_def.*"));
+        Assert.assertFalse(plString.matches(".*fileVal \"etc\".*"));
+        Assert.assertFalse(plString.matches(".*basicStruct.*"));
+    }
+
+    @Test
+    public void testSerializationAgainstConfigDefinitionAddedValsInDef() {
+        FunctionTestConfig config = ConfigInstancePayloadTest.createVariableAccessConfigWithBuilder();
+        InnerCNode def = new InnerCNode("function-test");
+        def.children().put("stringwithdef", LeafCNode.newInstance(stringType, def, "stringwithdef"));
+        def.children().put("someotherstring", LeafCNode.newInstance(stringType, def, "someotherstring", "some other"));
+        def.children().put("long_with_def", LeafCNode.newInstance(longType, def, "long_with_def"));
+        def.children().put("some_other_long", LeafCNode.newInstance(longType, def, "some_other_long", "88"));
+        def.children().put("some_other_enum", LeafCNode.newInstance(enumType(new String[]{"hey", "ho", "lets", "go"}), def, "some_other_enum", "lets"));
+        def.children().put("int_val_nofdef", LeafCNode.newInstance(intType, def, "int_val_nodef", null));
+
+        // But not double_with_def etc, and no structs/arrays
+        List<String> payload = Validator.serialize(config, def);
+        String plString = payload.toString();
+        Assert.assertTrue(plString.matches(".*long_with_def \\-9876543210.*"));
+        Assert.assertTrue(plString.matches(".*stringwithdef \"bar and foo\".*"));
+        Assert.assertTrue(plString.matches(".*.someotherstring \"some other\".*"));
+        Assert.assertTrue(plString.matches(".*some_other_long 88.*"));
+        Assert.assertTrue(plString.matches(".*some_other_enum lets.*"));
+        Assert.assertFalse(plString.matches(".*double_with_def.*"));
+        Assert.assertFalse(plString.matches(".*fileVal \"etc\".*"));
+        Assert.assertFalse(plString.matches(".*basicStruct.*"));
+        Assert.assertFalse(plString.matches(".*int_val_nodef.*"));
+    }
+
+    @Test
+    public void testSerializeAgainstConfigDefinitionMismatchAllWays() {
+        FunctionTestConfig config = ConfigInstancePayloadTest.createVariableAccessConfigWithBuilder();
+
+        // Create all sorts of mismatches in the def schema used to serialize
+        InnerCNode def = new InnerCNode("function-test");
+        def.children().put("long_with_def", LeafCNode.newInstance(longType, def, "long_with_def"));
+        def.children().put("stringwithdef", LeafCNode.newInstance(intType, def, "stringwithdef"));
+        def.children().put("basicStruct", LeafCNode.newInstance(intType, def, "basicStruct"));
+        InnerCNode doubleValWrong = new InnerCNode("double_val");
+        doubleValWrong.children().put("foo", LeafCNode.newInstance(intType, def, "foo"));
+        def.children().put("double_val", doubleValWrong);
+        InnerCNode myArray = new InnerCNode("myarray");
+        myArray.children().put("intval", LeafCNode.newInstance(stringType, myArray, "foo"));
+        InnerCNode myStruct = new InnerCNode("myStruct");
+        myStruct.children().put("a", LeafCNode.newInstance(stringType, myStruct, "foo"));
+        myArray.children().put("myStruct", myStruct);
+        def.children().put("myarray", myArray);
+
+        List<String> payload = Validator.serialize(config, def);
+        String plString = payload.toString();
+        Assert.assertTrue(plString.matches(".*long_with_def.*"));
+        Assert.assertFalse(plString.matches(".*stringwithdef.*"));
+        Assert.assertFalse(plString.matches(".*basicStruct.*"));
+        Assert.assertFalse(plString.matches(".*double_val.*"));
+        Assert.assertFalse(plString.matches(".*intval.*"));
+        Assert.assertFalse(plString.matches(".*\\.a.*"));
+    }
+
+    @Test
+    public void testSerializeAgainstConfigDefinitionComplex() {
+        FunctionTestConfig config = ConfigInstancePayloadTest.createVariableAccessConfigWithBuilder();
+
+        // Build a pretty complex def programatically
+        InnerCNode def = new InnerCNode("function-test");
+        def.children().put("stringwithdef", LeafCNode.newInstance(stringType, def, "stringwithdef"));
+        def.children().put("someUnknownStringNoDefault", LeafCNode.newInstance(stringType, def, "someUnknownStringNoDefault"));
+        InnerCNode basicStruct = new InnerCNode("basicStruct");
+        basicStruct.children().put("foo", LeafCNode.newInstance(stringType, def, "foo")); // but not bar
+        InnerCNode rootStruct = new InnerCNode("rootStruct");
+        InnerCNode inner1 = new InnerCNode("inner1");
+        InnerCNode someUnknwonStruct = new InnerCNode("someUnknownStruct");
+        InnerCNode someUnknownInner = new InnerCNode("someUnknownInner");
+        InnerCNode innerArr = new InnerCNode("innerArr");
+        rootStruct.children().put("inner1", inner1);
+        rootStruct.children().put("someUnknownStruct", someUnknwonStruct);
+        rootStruct.children().put("someUnknownInner", someUnknownInner);
+        rootStruct.children().put("innerArr", innerArr);
+        InnerCNode myarray = new InnerCNode("myarray");
+        InnerCNode unknownInner = new InnerCNode("unknownInner");
+        def.children().put("basicStruct", basicStruct);
+        def.children().put("rootStruct", rootStruct);
+        def.children().put("myarray", myarray);
+        def.children().put("unknownInner", unknownInner);
+        inner1.children().put("index", LeafCNode.newInstance(intType, inner1, "index"));
+        inner1.children().put("someUnknownInt", LeafCNode.newInstance(intType, inner1, "someUnknownInt", "-98"));
+        inner1.children().put("someUnknownIntNoDefault", LeafCNode.newInstance(intType, inner1, "someUnknownIntNoDefault"));
+        inner1.children().put("someUnknownEnum", LeafCNode.newInstance(enumType(new String[]{"goo", "go", "gorilla"}), inner1, "someUnknownEnum", "go"));
+        inner1.children().put("someUnknownEnumNoDefault", LeafCNode.newInstance(enumType(new String[]{"foo", "bar", "baz"}), inner1, "someUnknownEnumNoDefault"));
+        someUnknwonStruct.children().put("anint", LeafCNode.newInstance(intType, someUnknwonStruct, "anint", "3"));// But no instances of this in config
+        someUnknownInner.children().put("along", LeafCNode.newInstance(longType, someUnknownInner, "along", "234"));// No instance in config
+        innerArr.children().put("boolVal", LeafCNode.newInstance(boolType, innerArr, "boolVal"));
+        innerArr.children().put("someUnknownDouble", LeafCNode.newInstance(doubleType, innerArr, "someUnknownDouble", "-675.789"));
+        innerArr.children().put("someUnknownDoubleNoDefault", LeafCNode.newInstance(doubleType, innerArr, "someUnknownDoubleNoDefault"));
+        myarray.children().put("fileVal", LeafCNode.newInstance(fileType, myarray, "fileVal"));
+        myarray.children().put("stringval", new InnerCNode("stringval[]"));
+        // TODO make sure default for file is not allowed
+        //myarray.children().put("someUnknownFile", LeafCNode.newInstance(fileType, myarray, "someUnknownFile", "opt/"));
+        unknownInner.children().put("aDouble", LeafCNode.newInstance(doubleType, unknownInner, "aDouble", "1234"));
+        def.children().put("longarr", new InnerCNode("longarr[]"));
+        def.children().put("boolarr", new InnerCNode("boolarr[]"));
+        def.children().put("doublearr", new InnerCNode("doublearr[]"));
+        def.children().put("stringarr", new InnerCNode("stringarr[]"));
+        def.children().put("fileArr", new InnerCNode("fileArr[]"));
+        def.children().put("refarr", new InnerCNode("refarr[]"));
+        def.children().put("enumarr", new InnerCNode("enumarr[]"));
+        List<String> payload = Validator.serialize(config, def);
+        String plString = payload.toString();
+        Assert.assertFalse(plString.matches(".*long_with_def \\-9876543210.*"));
+        Assert.assertFalse(plString.matches(".*someUnknownStringNoDefault.*"));
+        Assert.assertTrue(plString.matches(".*stringwithdef \"bar and foo\".*"));
+        Assert.assertFalse(plString.matches(".*double_with_def.*"));
+        Assert.assertFalse(plString.matches(".*fileVal etc.*"));
+        Assert.assertTrue(plString.matches(".*basicStruct\\.foo \"basicFoo\".*"));
+        Assert.assertFalse(plString.matches(".*basicStruct\\.bar.*"));
+        Assert.assertFalse(plString.matches(".*rootStruct\\.inner0.*"));
+        Assert.assertFalse(plString.matches(".*unknownInner.*"));
+        Assert.assertFalse(plString.matches(".*rootStruct\\.someUnknownStruct.*"));
+        Assert.assertFalse(plString.matches(".*rootStruct\\.someUnknownInner.*"));
+        Assert.assertFalse(plString.matches(".*rootStruct\\.inner1\\.name.*"));
+        Assert.assertTrue(plString.matches(".*rootStruct\\.inner1\\.index 12.*"));
+        Assert.assertTrue(plString.matches(".*rootStruct\\.inner1\\.someUnknownInt -98.*"));
+        Assert.assertTrue(plString.matches(".*rootStruct\\.inner1\\.someUnknownEnum go.*"));
+        Assert.assertTrue(plString.matches(".*rootStruct\\.innerArr\\[0\\]\\.boolVal true.*"));
+        Assert.assertFalse(plString.matches(".*someUnknownEnumNoDefault.*"));
+        Assert.assertFalse(plString.matches(".*someUnknownDoubleNoDefault.*"));
+        Assert.assertFalse(plString.matches(".*someUnknownIntNoDefault.*"));
+        Assert.assertTrue(plString.matches(".*rootStruct\\.innerArr\\[0\\]\\.someUnknownDouble -675.789.*"));
+        Assert.assertFalse(plString.matches(".*rootStruct\\.innerArr\\[0\\]\\.stringVal*"));
+        Assert.assertFalse(plString.matches(".*myarray\\[0\\].intval.*"));
+        Assert.assertTrue(plString.matches(".*myarray\\[0\\].fileVal \"file0\".*"));
+        //assertTrue(plString.matches(".*myarray\\[0\\].someUnknownFile \"opt/\".*"));
+        Assert.assertTrue(plString.matches(".*myarray\\[0\\].stringval\\[0\\] \"baah\".*"));
+        Assert.assertTrue(plString.matches(".*myarray\\[0\\].stringval\\[1\\] \"yikes\".*"));
+        Assert.assertTrue(plString.matches(".*myarray\\[1\\].fileVal \"file1\".*"));
+        Assert.assertFalse(plString.matches(".*myarray\\[1\\].enumVal.*"));
+        Assert.assertFalse(plString.matches(".*myarray\\[1\\].refVal.*"));
+        Assert.assertTrue(plString.matches(".*boolarr\\[0\\] false.*"));
+        Assert.assertTrue(plString.matches(".*longarr\\[0\\] 9223372036854775807.*"));
+        Assert.assertTrue(plString.matches(".*longarr\\[1\\] -9223372036854775808.*"));
+        Assert.assertTrue(plString.matches(".*doublearr\\[0\\] 2344\\.0.*"));
+        Assert.assertTrue(plString.matches(".*doublearr\\[1\\] 123\\.0.*"));
+        Assert.assertTrue(plString.matches(".*stringarr\\[0\\] \"bar\".*"));
+        Assert.assertTrue(plString.matches(".*enumarr\\[0\\] VALUES.*"));
+        Assert.assertTrue(plString.matches(".*refarr\\[0\\] \\:parent\\:.*"));
+        Assert.assertTrue(plString.matches(".*refarr\\[1\\] \\:parent.*"));
+        Assert.assertTrue(plString.matches(".*refarr\\[2\\] parent\\:.*"));
+        Assert.assertTrue(plString.matches(".*fileArr\\[0\\] \"bin\".*"));
+    }
+
+    private DefLine.Type enumType(String[] strings) {
+        return new DefLine.Type("enum").setEnumArray(strings);
+    }
+**/
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/ConfigInstanceSerializerTest.java b/config/src/test/java/com/yahoo/config/subscription/ConfigInstanceSerializerTest.java
new file mode 100644
index 00000000000..d3713eaa401
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/ConfigInstanceSerializerTest.java
@@ -0,0 +1,229 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.foo.ArraytypesConfig;
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.foo.SimpletypesConfig;
+import com.yahoo.foo.SpecialtypesConfig;
+import com.yahoo.foo.StructtypesConfig;
+import com.yahoo.foo.MaptypesConfig;
+import com.yahoo.slime.JsonFormat;
+import com.yahoo.slime.Slime;
+
+import org.junit.Test;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+
+import static com.yahoo.config.subscription.util.JsonHelper.assertJsonEquals;
+import static com.yahoo.config.subscription.util.JsonHelper.inputJson;
+import static org.junit.Assert.fail;
+
+/**
+ * @author lulf
+ * @author Vegard Sjonfjell
+ * @since 5.1
+ */
+public class ConfigInstanceSerializerTest {
+    @Test
+    public void test_that_leaf_types_are_serialized_to_json_types() throws IOException {
+        SimpletypesConfig.Builder builder = new SimpletypesConfig.Builder();
+        builder.boolval(false);
+        builder.stringval("foo");
+        builder.intval(13);
+        builder.longval(14);
+        builder.doubleval(3.14);
+        builder.enumval(SimpletypesConfig.Enumval.Enum.VAL2);
+
+        final SimpletypesConfig config = new SimpletypesConfig(builder);
+        final String expectedJson = inputJson(
+                "{",
+                "    'boolval': false,",
+                "    'doubleval': 3.14,",
+                "    'enumval': 'VAL2',",
+                "    'intval': 13,",
+                "    'longval': 14,",
+                "    'stringval': 'foo'",
+                "}"
+        );
+
+        assertConfigEquals(expectedJson, config);
+    }
+
+    @Test
+    public void test_that_nested_structs_are_formatted_to_json() throws IOException {
+        StructtypesConfig.Builder builder = new StructtypesConfig.Builder();
+        StructtypesConfig.Nested.Builder nestedBuilder = new StructtypesConfig.Nested.Builder();
+        StructtypesConfig.Nested.Inner.Builder innerBuilder = new StructtypesConfig.Nested.Inner.Builder();
+        innerBuilder.name("foo");
+        innerBuilder.emails("lulf@foo");
+        innerBuilder.emails("lulf@bar");
+        innerBuilder.gender(StructtypesConfig.Nested.Inner.Gender.Enum.MALE);
+        nestedBuilder.inner(innerBuilder);
+        builder.nested(nestedBuilder);
+        StructtypesConfig.Nestedarr.Builder nestedArrBuilder = new StructtypesConfig.Nestedarr.Builder();
+        StructtypesConfig.Nestedarr.Inner.Builder innerNestedArrBuilder = new StructtypesConfig.Nestedarr.Inner.Builder();
+        innerNestedArrBuilder.emails("foo@bar");
+        innerNestedArrBuilder.name("bar");
+        innerNestedArrBuilder.gender(StructtypesConfig.Nestedarr.Inner.Gender.Enum.FEMALE);
+        nestedArrBuilder.inner(innerNestedArrBuilder);
+        builder.nestedarr(nestedArrBuilder);
+
+        final StructtypesConfig config = new StructtypesConfig(builder);
+        final String expectedJson = inputJson(
+                "{",
+                "    'complexarr': [],",
+                "    'nested': {",
+                "        'inner': {",
+                "            'emails': [",
+                "                'lulf@foo',",
+                "                'lulf@bar'",
+                "            ],",
+                "            'gender': 'MALE',",
+                "            'name': 'foo'",
+                "        }",
+                "    },",
+                "    'nestedarr': [",
+                "        {",
+                "            'inner': {",
+                "                'emails': [",
+                "                    'foo@bar'",
+                "                ],",
+                "                'gender': 'FEMALE',",
+                "                'name': 'bar'",
+                "            }",
+                "        }",
+                "    ],",
+                "    'simple': {",
+                "        'emails': [],",
+                "        'gender': 'MALE',",
+                "        'name': '_default_'",
+                "    },",
+                "    'simplearr': []",
+                "}"
+        );
+
+        assertConfigEquals(expectedJson, config);
+    }
+
+    @Test
+    public void test_that_arrays_are_formatted_to_json() throws IOException {
+        ArraytypesConfig.Builder builder = new ArraytypesConfig.Builder();
+        builder.boolarr(true);
+        builder.boolarr(false);
+        builder.doublearr(1.2);
+        builder.doublearr(1.1);
+        builder.enumarr(ArraytypesConfig.Enumarr.Enum.VAL1);
+        builder.enumarr(ArraytypesConfig.Enumarr.Enum.VAL2);
+        builder.intarr(3);
+        builder.longarr(4l);
+        builder.stringarr("foo");
+
+        final ArraytypesConfig config = new ArraytypesConfig(builder);
+        final String expectedJson = inputJson(
+                "{",
+                "    'boolarr': [",
+                "        true,",
+                "        false",
+                "    ],",
+                "    'doublearr': [",
+                "        1.2,",
+                "        1.1",
+                "    ],",
+                "    'enumarr': [",
+                "        'VAL1',",
+                "        'VAL2'",
+                "    ],",
+                "    'intarr': [",
+                "        3",
+                "    ],",
+                "    'longarr': [",
+                "        4",
+                "    ],",
+                "    'stringarr': [",
+                "        'foo'",
+                "    ]",
+                "}"
+        );
+
+        assertConfigEquals(expectedJson, config);
+    }
+
+    @Test
+    public void test_that_maps_are_formatted_to_json() throws IOException {
+        MaptypesConfig.Builder builder = new MaptypesConfig.Builder();
+        builder.boolmap("foo", true);
+        builder.intmap("bar", 3);
+        builder.stringmap("hei", "hallo");
+        MaptypesConfig.Innermap.Builder inner = new MaptypesConfig.Innermap.Builder();
+        inner.foo(133);
+        builder.innermap("baz", inner);
+        MaptypesConfig.Nestedmap.Builder nested = new MaptypesConfig.Nestedmap.Builder();
+        nested.inner("foo", 33);
+        builder.nestedmap("bim", nested);
+
+        final MaptypesConfig config = new MaptypesConfig(builder);
+        final String expectedJson = inputJson(
+                "{",
+                "  'boolmap': {",
+                "        'foo': true",
+                "    },",
+                "    'doublemap': {},",
+                "    'filemap': {},",
+                "    'innermap': {",
+                "        'baz': {",
+                "            'foo': 133",
+                "        }",
+                "    },",
+                "    'intmap': {",
+                "        'bar': 3",
+                "    },",
+                "    'longmap': {},",
+                "    'nestedmap': {",
+                "        'bim': {",
+                "            'inner': {",
+                "                'foo': 33",
+                "            }",
+                "        }",
+                "    },",
+                "    'stringmap': {",
+                "        'hei': 'hallo'",
+                "    }",
+                "}"
+        );
+
+        assertConfigEquals(expectedJson, config);
+    }
+
+    @Test
+    public void test_that_non_standard_types_are_formatted_as_json_strings() throws IOException {
+        SpecialtypesConfig.Builder builder = new SpecialtypesConfig.Builder();
+        builder.myfile("thefilename");
+        builder.myref("thereference");
+
+        final SpecialtypesConfig config = new SpecialtypesConfig(builder);
+        final String expectedJson = inputJson(
+                "{",
+                "    'myfile': 'thefilename',",
+                "    'myref': 'thereference'",
+                "}"
+        );
+
+        assertConfigEquals(expectedJson, config);
+    }
+
+    static void assertConfigEquals(String expectedJson, ConfigInstance config) {
+        Slime slime = new Slime();
+        ConfigInstance.serialize(config, new ConfigInstanceSerializer(slime));
+        JsonFormat jsonFormat = new JsonFormat(true);
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+
+        try {
+            jsonFormat.encode(baos, slime);
+        } catch (IOException e) {
+            fail();
+        }
+
+        assertJsonEquals(baos.toString(), expectedJson);
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/ConfigInstanceTest.java b/config/src/test/java/com/yahoo/config/subscription/ConfigInstanceTest.java
new file mode 100644
index 00000000000..ea7312ec7ef
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/ConfigInstanceTest.java
@@ -0,0 +1,119 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.foo.AppConfig;
+import com.yahoo.foo.TestNonstringConfig;
+import org.junit.Ignore;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.fail;
+
+/**
+ * Tests different aspects of the ConfigInstance class and its underlying Nodes.
+ *
+ * @author <a href="gv@yahoo-inc.com">G. Voldengen</a>
+ */
+public class ConfigInstanceTest {
+    private ConfigSourceSet sourceSet = new ConfigSourceSet("config-instance-test");
+
+    /**
+     * Verifies that the subscriber's configure() method is only
+     * called once upon subscribe, even if there are more than one
+     * subscribers to the same ConfigInstance. This has previously
+     * been a problem, since ConfigInstance.subscribe() called
+     * configureSubscriber(), which configures all subscribers to the
+     * instance. Now, the new method configureSubscriber(Subscriber)
+     * is called instead.
+     */
+    @Test
+    public void testConfigureOnlyOnceUponSubscribe() {
+        final String configId = "raw:times 1\n";
+        AppService service1 = new AppService(configId, sourceSet);
+        AppService service2 = new AppService(configId, sourceSet);
+
+        assertEquals(1, service1.timesConfigured());
+        assertEquals(1, service2.timesConfigured());
+    }
+
+    /**
+     * Verifies that values set in previous setConfig() calls are
+     * retained when the payload in a new setConfig() call does not
+     * overwrite them.
+     */
+    @Test
+    @Ignore
+    public void testRetainOldValuesOnConfigUpdates() {
+        AppConfig config = new AppConfig(new AppConfig.Builder());
+        //config.setConfig(Arrays.asList("message \"one\"", "times 333"), "", 0L);
+        assertEquals("one", config.message());
+        assertEquals(333, config.times());
+
+        //config.setConfig(Arrays.asList("message \"two\""), "", 0L);
+        assertEquals("two", config.message());
+        assertEquals("config.times retains previously set value", 333, config.times());
+
+        //config.setConfig(Arrays.asList("times 666"), "", 0L);
+        assertEquals("config.message retains previously set value", "two", config.message());
+        assertEquals(666, config.times());
+    }
+
+    /**
+     * Verifies that an exception is thrown when one attempts to set an
+     * illegal config value for parameters that have default values.
+     */
+    @Test
+    public void testFailUponIllegalValue() {
+        verifyIllegalValue("i notAnInt");
+        verifyIllegalValue("i 3.0");
+
+        verifyIllegalValue("d noDouble");
+        verifyIllegalValue("d 3.0.");
+
+        // verifyIllegalValue("b notTrueOrFalse");
+        //verifyIllegalValue("b 1");
+        //verifyIllegalValue("b 0");
+
+        verifyIllegalValue("e undeclaredEnumValue");
+        verifyIllegalValue("e 0");
+    }
+
+    private void verifyIllegalValue(String line) {
+        String configId = "raw:" + line + "\n";
+        try {
+            new TestNonstring(configId);
+            fail("Expected ConfigurationRuntimeException when setting a parameter value of wrong type.");
+        } catch (RuntimeException expected) {
+            verifyException(expected, "Not able to create config builder for payload", "Got ConfigurationRuntimeException for the wrong reason. " +
+                    "Expected to fail when setting a parameter value of wrong type.");
+        }
+
+    }
+
+    private void verifyException(Throwable throwable, String expected, String failMessage) {
+        Throwable t = throwable;
+        boolean ok = false;
+        while (t != null) {
+            if (t.getMessage() != null && t.getMessage().contains(expected)) {
+                ok = true;
+                break;
+            }
+            t = t.getCause();
+        }
+        if (!ok) {
+            throwable.printStackTrace();
+            fail(failMessage);
+        }
+    }
+
+    private class TestNonstring {
+        private final ConfigSubscriber subscriber;
+        private final ConfigHandle<TestNonstringConfig> handle;
+        public TestNonstring(String configId) {
+            subscriber = new ConfigSubscriber();
+            handle = subscriber.subscribe(TestNonstringConfig.class, configId);
+            subscriber.nextConfig();
+            handle.getConfig();
+        }
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/ConfigInstanceUtilTest.java b/config/src/test/java/com/yahoo/config/subscription/ConfigInstanceUtilTest.java
new file mode 100644
index 00000000000..36ea09db1dc
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/ConfigInstanceUtilTest.java
@@ -0,0 +1,172 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.config.ConfigBuilder;
+import com.yahoo.config.ConfigurationRuntimeException;
+import com.yahoo.config.FileReference;
+import com.yahoo.foo.FunctionTestConfig;
+import com.yahoo.foo.TestNodefsConfig;
+import com.yahoo.vespa.config.ConfigPayload;
+import com.yahoo.vespa.config.ConfigPayloadBuilder;
+import org.junit.Test;
+
+import java.io.File;
+import java.util.Arrays;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.containsString;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertThat;
+import static com.yahoo.foo.FunctionTestConfig.*;
+
+/**
+ * @author lulf
+ * @since 5.1
+ */
+public class ConfigInstanceUtilTest {
+
+    @Test
+    public void require_that_builder_values_can_be_overridden_by_another_builder() {
+        FunctionTestConfig.Builder destination = createVariableAccessBuilder();
+
+        FunctionTestConfig.Builder source = new FunctionTestConfig.Builder()
+                .int_val(-1)
+                .intarr(0)
+                .doublearr(0.0)
+                .basicStruct(new FunctionTestConfig.BasicStruct.Builder()
+                        .bar(-1)
+                        .intArr(0))
+                .myarray(new FunctionTestConfig.Myarray.Builder()
+                        .intval(-1)
+                        .refval("")
+                        .fileVal("")
+                        .myStruct(new FunctionTestConfig.Myarray.MyStruct.Builder()
+                                .a(0)
+                        ));
+
+        ConfigInstanceUtil.setValues(destination, source);
+
+        FunctionTestConfig result = new FunctionTestConfig(destination);
+        assertThat(result.int_val(), is(-1));
+        assertThat(result.string_val(), is("foo"));
+        assertThat(result.intarr().size(), is(1));
+        assertThat(result.intarr(0), is(0));
+        assertThat(result.longarr().size(), is(2));
+        assertThat(result.doublearr().size(), is(3));
+        assertEquals(2344.0, result.doublearr(0), 0.01);
+        assertEquals(123.0, result.doublearr(1), 0.01);
+        assertEquals(0.0, result.doublearr(2), 0.01);
+        assertThat(result.basicStruct().bar(), is(-1));
+        assertThat(result.basicStruct().foo(), is("basicFoo"));
+        assertThat(result.basicStruct().intArr().size(), is(3));
+        assertThat(result.basicStruct().intArr(0), is(310));
+        assertThat(result.basicStruct().intArr(1), is(311));
+        assertThat(result.basicStruct().intArr(2), is(0));
+        assertThat(result.myarray().size(), is(3));
+        assertThat(result.myarray(2).intval(), is(-1));
+        assertThat(result.myarray(2).refval(), is(""));
+        assertThat(result.myarray(2).fileVal().value(), is(""));
+        assertThat(result.myarray(2).myStruct().a(), is(0));
+
+    }
+
+    @Test(expected = ConfigurationRuntimeException.class)
+    public void require_that_invalid_builders_fail() {
+        ConfigInstanceUtil.setValues(new FakeBuilder(), new FakeBuilder());
+    }
+
+    private static class FakeBuilder implements ConfigBuilder {
+    }
+
+    static FunctionTestConfig.Builder createVariableAccessBuilder() {
+        return new FunctionTestConfig.Builder().
+                bool_val(false).
+                bool_with_def(true).
+                int_val(5).
+                int_with_def(-14).
+                long_val(12345678901L).
+                long_with_def(-9876543210L).
+                double_val(41.23).
+                double_with_def(-12).
+                string_val("foo").
+                stringwithdef("bar and foo").
+                enum_val(Enum_val.FOOBAR).
+                enumwithdef(Enumwithdef.BAR2).
+                refval(":parent:").
+                refwithdef(":parent:").
+                fileVal("etc").
+                pathVal(FileReference.mockFileReferenceForUnitTesting(new File("src/test/resources/configs/def-files/function-test.def"))).
+                boolarr(false).
+                longarr(9223372036854775807L).
+                longarr(-9223372036854775808L).
+                doublearr(2344.0).
+                doublearr(123.0).
+                stringarr("bar").
+                enumarr(Enumarr.VALUES).
+                refarr(Arrays.asList(":parent:", ":parent", "parent:")).  // test collection based setter
+                fileArr("bin").
+
+                basicStruct(new FunctionTestConfig.BasicStruct.Builder().
+                        foo("basicFoo").
+                        bar(3).
+                        intArr(310).intArr(311)).
+
+                rootStruct(new FunctionTestConfig.RootStruct.Builder().
+                        inner0(new FunctionTestConfig.RootStruct.Inner0.Builder().
+                                index(11)).
+                        inner1(new FunctionTestConfig.RootStruct.Inner1.Builder().
+                                index(12)).
+                        innerArr(new FunctionTestConfig.RootStruct.InnerArr.Builder().
+                                boolVal(true).
+                                stringVal("deep")).
+                        innerArr(new FunctionTestConfig.RootStruct.InnerArr.Builder().
+                                boolVal(false).
+                                stringVal("blue a=\"escaped\""))).
+
+                myarray(new FunctionTestConfig.Myarray.Builder().
+                        intval(-5).
+                        stringval("baah").
+                        stringval("yikes").
+                        enumval(Myarray.Enumval.INNER).
+                        refval(":parent:").
+                        fileVal("file0").
+                        anotherarray(new FunctionTestConfig.Myarray.Anotherarray.Builder().
+                                foo(7)).
+                        myStruct(new FunctionTestConfig.Myarray.MyStruct.Builder().
+                                a(1).
+                                b(2))).
+
+                myarray(new FunctionTestConfig.Myarray.Builder().
+                        intval(5).
+                        enumval(Myarray.Enumval.INNER).
+                        refval(":parent:").
+                        fileVal("file1").
+                        anotherarray(new FunctionTestConfig.Myarray.Anotherarray.Builder().
+                                foo(1).
+                                foo(2)).
+                        myStruct(new FunctionTestConfig.Myarray.MyStruct.Builder().
+                                a(-1).
+                                b(-2)));
+
+    }
+
+    @Test
+    public void test_require_private_getter() {
+        FunctionTestConfig.Builder builder = createVariableAccessBuilder();
+        assertEquals(ConfigInstanceUtil.getField(builder, "int_val"), 5);
+        FunctionTestConfig conf = new FunctionTestConfig(builder);
+        assertEquals(conf.int_val(), 5);
+    }
+
+    @Test
+    public void testGetNewInstanceErrorMessage() {
+        ConfigPayloadBuilder payloadBuilder = new ConfigPayloadBuilder();
+        try {
+            ConfigInstanceUtil.getNewInstance(TestNodefsConfig.class, "id0", ConfigPayload.fromBuilder(payloadBuilder));
+            assert(false);
+        } catch (IllegalArgumentException e) {
+            assertThat(e.getMessage(), containsString("Failed creating new instance of 'com.yahoo.foo.TestNodefsConfig' for config id 'id0':"));
+        }
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/ConfigInterruptedExceptionTest.java b/config/src/test/java/com/yahoo/config/subscription/ConfigInterruptedExceptionTest.java
new file mode 100644
index 00000000000..d760a1c1b72
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/ConfigInterruptedExceptionTest.java
@@ -0,0 +1,19 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import org.junit.Test;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author lulf
+ * @since 5.1
+ */
+public class ConfigInterruptedExceptionTest {
+    @Test
+    public void require_that_throwable_is_preserved() {
+        ConfigInterruptedException e = new ConfigInterruptedException(new RuntimeException("foo"));
+        assertThat(e.getCause().getMessage(), is("foo"));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/ConfigSetSubscriptionTest.java b/config/src/test/java/com/yahoo/config/subscription/ConfigSetSubscriptionTest.java
new file mode 100644
index 00000000000..adbc11b7ca0
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/ConfigSetSubscriptionTest.java
@@ -0,0 +1,133 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import static org.junit.Assert.*;
+
+import com.yahoo.foo.AppConfig;
+import com.yahoo.foo.SimpletypesConfig;
+import com.yahoo.foo.StringConfig;
+import com.yahoo.config.subscription.impl.ConfigSubscription;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.TimingValues;
+import org.junit.Test;
+
+public class ConfigSetSubscriptionTest {
+
+    @Test
+    public void testConfigSubscription() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        ConfigSet configSet = new ConfigSet();
+        AppConfig.Builder a0builder = new AppConfig.Builder().message("A message, 0").times(88);
+        configSet.addBuilder("app/0", a0builder);
+        AppConfig.Builder a1builder = new AppConfig.Builder().message("A message, 1").times(89);
+        configSet.addBuilder("app/1", a1builder);
+
+        ConfigSubscription<AppConfig> c1 = ConfigSubscription.get(
+                new ConfigKey<>(AppConfig.class, "app/0"),
+                subscriber,
+                configSet,
+                new TimingValues());
+        ConfigSubscription<AppConfig> c2 = ConfigSubscription.get(
+                new ConfigKey<>(AppConfig.class, "app/1"),
+                subscriber,
+                configSet,
+                new TimingValues());
+
+        assertTrue(c1.equals(c1));
+        assertFalse(c1.equals(c2));
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testUnknownKey() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        ConfigSet configSet = new ConfigSet();
+        AppConfig.Builder a0builder = new AppConfig.Builder().message("A message, 0").times(88);
+        configSet.addBuilder("app/0", a0builder);
+
+        ConfigSubscription.get(
+                new ConfigKey<>(SimpletypesConfig.class, "simpletypes/1"),
+                subscriber,
+                configSet,
+                new TimingValues());
+    }
+
+    @Test
+    public void testConfigSetBasic() {
+        ConfigSet myConfigs = new ConfigSet();
+        AppConfig.Builder a0builder = new AppConfig.Builder().message("A message, 0").times(88);
+        AppConfig.Builder a1builder = new AppConfig.Builder().message("A message, 1").times(89);
+        StringConfig.Builder barBuilder = new StringConfig.Builder().stringVal("StringVal");
+        myConfigs.addBuilder("app/0", a0builder);
+        myConfigs.addBuilder("app/1", a1builder);
+        myConfigs.addBuilder("bar", barBuilder);
+        ConfigSubscriber subscriber = new ConfigSubscriber(myConfigs);
+        ConfigHandle<AppConfig> hA0 = subscriber.subscribe(AppConfig.class, "app/0");
+        ConfigHandle<AppConfig> hA1 = subscriber.subscribe(AppConfig.class, "app/1");
+        ConfigHandle<StringConfig> hS = subscriber.subscribe(StringConfig.class, "bar");
+
+        assertTrue(subscriber.nextConfig(0));
+        assertTrue(hA0.isChanged());
+        assertTrue(hA1.isChanged());
+        assertTrue(hS.isChanged());
+
+        assertEquals(hA0.getConfig().message(), "A message, 0");
+        assertEquals(hA1.getConfig().message(), "A message, 1");
+        assertEquals(hA0.getConfig().times(), 88);
+        assertEquals(hA1.getConfig().times(), 89);
+
+        assertFalse(subscriber.nextConfig(10));
+        assertFalse(hA0.isChanged());
+        assertFalse(hA1.isChanged());
+        assertFalse(hS.isChanged());
+        assertEquals(hA0.getConfig().message(), "A message, 0");
+        assertEquals(hA1.getConfig().message(), "A message, 1");
+        assertEquals(hA0.getConfig().times(), 88);
+        assertEquals(hA1.getConfig().times(), 89);
+        assertEquals(hS.getConfig().stringVal(), "StringVal");
+
+        //Reconfigure all configs, generation should change
+        a0builder.message("A new message, 0").times(880);
+        a1builder.message("A new message, 1").times(890);
+        barBuilder.stringVal("new StringVal");
+        subscriber.reload(1);
+        assertTrue(subscriber.nextConfig(0));
+        assertTrue(hA0.isChanged());
+        assertTrue(hA1.isChanged());
+        assertTrue(hS.isChanged());
+
+        assertEquals(hA0.getConfig().message(), "A new message, 0");
+        assertEquals(hA1.getConfig().message(), "A new message, 1");
+        assertEquals(hA0.getConfig().times(), 880);
+        assertEquals(hA1.getConfig().times(), 890);
+        assertEquals(hS.getConfig().stringVal(), "new StringVal");
+
+        // Reconfigure only one
+        a0builder.message("Another new message, 0").times(8800);
+        subscriber.reload(2);
+        assertTrue(subscriber.nextConfig(0));
+        assertTrue(hA0.isChanged());
+        assertFalse(hA1.isChanged());
+        assertFalse(hS.isChanged());
+
+        assertEquals(hA0.getConfig().message(), "Another new message, 0");
+        assertEquals(hA1.getConfig().message(), "A new message, 1");
+        assertEquals(hA0.getConfig().times(), 8800);
+        assertEquals(hA1.getConfig().times(), 890);
+        assertEquals(hS.getConfig().stringVal(), "new StringVal");
+
+        //Reconfigure only one, and only one field on the builder
+        a1builder.message("Yet another message, 1");
+        subscriber.reload(3);
+        assertTrue(subscriber.nextConfig(0));
+        assertFalse(hA0.isChanged());
+        assertTrue(hA1.isChanged());
+        assertFalse(hS.isChanged());
+
+        assertEquals(hA0.getConfig().message(), "Another new message, 0");
+        assertEquals(hA1.getConfig().message(), "Yet another message, 1");
+        assertEquals(hA0.getConfig().times(), 8800);
+        assertEquals(hA1.getConfig().times(), 890);
+        assertEquals(hS.getConfig().stringVal(), "new StringVal");
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/ConfigSetTest.java b/config/src/test/java/com/yahoo/config/subscription/ConfigSetTest.java
new file mode 100644
index 00000000000..668fa68d264
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/ConfigSetTest.java
@@ -0,0 +1,24 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.foo.SimpletypesConfig;
+import org.junit.Test;
+
+import java.util.regex.Pattern;
+
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author lulf
+ * @since 5.1
+ */
+public class ConfigSetTest {
+    @Test
+    public void testToString() {
+        ConfigSet set = new ConfigSet();
+        SimpletypesConfig.Builder builder = new SimpletypesConfig.Builder();
+        set.addBuilder("foo", builder);
+        assertTrue(Pattern.matches("name=simpletypes,namespace=foo,configId=foo=>com.yahoo.foo.SimpletypesConfig.*",
+                set.toString()));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/ConfigSourceSetTest.java b/config/src/test/java/com/yahoo/config/subscription/ConfigSourceSetTest.java
new file mode 100755
index 00000000000..23633a62cca
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/ConfigSourceSetTest.java
@@ -0,0 +1,68 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import org.junit.Test;
+import org.junit.After;
+
+import java.util.Set;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.*;
+
+/**
+ * @author <a href="gv@yahoo-inc.com">G. Voldengen</a>
+ */
+public class ConfigSourceSetTest {
+    @Test
+    public void testEquals() {
+        assertTrue(new ConfigSourceSet().equals(new ConfigSourceSet()));
+        assertFalse(new ConfigSourceSet().equals(new ConfigSourceSet(new String[]{"a"})));
+
+        assertTrue(new ConfigSourceSet(new String[]{"a"}).equals(new ConfigSourceSet(new String[]{"a"})));
+        assertTrue(new ConfigSourceSet(new String[]{"a"}).equals(new ConfigSourceSet(new String[]{"  A  "})));
+        assertTrue(new ConfigSourceSet(new String[]{"a"}).equals(new ConfigSourceSet(new String[]{"A", "a"})));
+        assertTrue(new ConfigSourceSet(new String[]{"A"}).equals(new ConfigSourceSet(new String[]{"a", " a  "})));
+
+        assertFalse(new ConfigSourceSet(new String[]{"a"}).equals(new ConfigSourceSet(new String[]{"b"})));
+        assertFalse(new ConfigSourceSet(new String[]{"a"}).equals(new ConfigSourceSet(new String[]{"a", "b"})));
+
+        assertTrue(new ConfigSourceSet(new String[]{"a", "b"}).equals(new ConfigSourceSet(new String[]{"a", "b"})));
+        assertTrue(new ConfigSourceSet(new String[]{"b", "a"}).equals(new ConfigSourceSet(new String[]{"a", "b"})));
+        assertTrue(new ConfigSourceSet(new String[]{"A", " b"}).equals(new ConfigSourceSet(new String[]{"a ", "B"})));
+        assertTrue(new ConfigSourceSet(new String[]{"b", "a", "c"})
+                .equals(new ConfigSourceSet(new String[]{"a", "b", "c"})));
+
+        assertFalse(new ConfigSourceSet(new String[]{"a", "b"}).equals(new ConfigSourceSet(new String[]{"b", "c"})));
+        assertFalse(new ConfigSourceSet().equals("foo"));
+    }
+
+    @Test
+    public void testIterationOrder() {
+        String[] hosts = new String[]{"primary", "fallback", "last-resort"};
+        ConfigSourceSet css = new ConfigSourceSet(hosts);
+
+        Set<String> sources = css.getSources();
+        assertEquals(hosts.length, sources.size());
+        int i = 0;
+        for (String s : sources) {
+            assertEquals(hosts[i++], s);
+        }
+    }
+
+    @Test
+    public void testDefaultSourceFromProperty() {
+        // TODO: Unable to set environment, so only able to test property usage for now
+        System.setProperty("configsources", "foo:123,bar:345,tcp/baz:333,quux");
+        ConfigSourceSet set = ConfigSourceSet.createDefault();
+        assertThat(set.getSources().size(), is(4));
+        assertTrue(set.getSources().contains("tcp/foo:123"));
+        assertTrue(set.getSources().contains("tcp/bar:345"));
+        assertTrue(set.getSources().contains("tcp/baz:333"));
+        assertTrue(set.getSources().contains("tcp/quux"));
+    }
+
+    @After
+    public void cleanup() {
+        System.clearProperty("configsources");
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/ConfigSourceTest.java b/config/src/test/java/com/yahoo/config/subscription/ConfigSourceTest.java
new file mode 100644
index 00000000000..d928592ebe9
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/ConfigSourceTest.java
@@ -0,0 +1,45 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.foo.SimpletypesConfig;
+import org.junit.Rule;
+import org.junit.Test;
+import org.junit.rules.TemporaryFolder;
+
+import java.io.File;
+import java.io.IOException;
+
+import static junit.framework.TestCase.fail;
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+/**
+ * @author lulf
+ * @since 5.1
+ */
+public class ConfigSourceTest {
+    @Test(expected = IllegalArgumentException.class)
+    public void require_that_FileSource_throws_exception_on_invalid_file() {
+        new FileSource(new File("invalid"));
+    }
+
+    @Test(expected = IllegalArgumentException.class)
+    public void require_that_DirSource_throws_exception_on_invalid_dir() {
+        new DirSource(new File("invalid"));
+    }
+
+    @Rule
+    public TemporaryFolder tmpDir = new TemporaryFolder();
+
+    @Test
+    public void require_that_DirSource_throws_exception_on_missing_file() throws IOException {
+        File folder = tmpDir.newFolder();
+        DirSource dirSource = new DirSource(folder);
+        try {
+            ConfigGetter.getConfig(SimpletypesConfig.class, "dir:" + tmpDir, dirSource);
+            fail();
+        } catch (IllegalArgumentException e) {
+            assertThat(e.getMessage(), is("Could not find a config file for '" + SimpletypesConfig.getDefName() + "' in '" + folder + "/'"));
+        }
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/ConfigSubscriptionTest.java b/config/src/test/java/com/yahoo/config/subscription/ConfigSubscriptionTest.java
new file mode 100644
index 00000000000..9fa299aef83
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/ConfigSubscriptionTest.java
@@ -0,0 +1,100 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.ConfigurationRuntimeException;
+import com.yahoo.foo.SimpletypesConfig;
+import com.yahoo.foo.AppConfig;
+import com.yahoo.config.subscription.impl.ConfigSubscription;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.TimingValues;
+
+import org.junit.Ignore;
+import org.junit.Test;
+
+import java.util.Collections;
+import java.util.List;
+
+import static junit.framework.TestCase.fail;
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.not;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author musum, lulf
+ * @since 5.1
+ */
+public class ConfigSubscriptionTest {
+    @Test
+    public void testEquals() {
+        ConfigSubscriber sub = new ConfigSubscriber();
+        final String payload = "boolval true";
+        ConfigSubscription<SimpletypesConfig> a = ConfigSubscription.get(new ConfigKey<>(SimpletypesConfig.class, "test"),
+                sub, new RawSource(payload), new TimingValues());
+        ConfigSubscription<SimpletypesConfig> b = ConfigSubscription.get(new ConfigKey<>(SimpletypesConfig.class, "test"),
+                sub, new RawSource(payload), new TimingValues());
+        ConfigSubscription<SimpletypesConfig> c = ConfigSubscription.get(new ConfigKey<>(SimpletypesConfig.class, "test2"),
+                sub, new RawSource(payload), new TimingValues());
+        assertThat(a, is(b));
+        assertThat(a, is(a));
+        assertThat(b, is(b));
+        assertThat(c, is(c));
+        assertThat(a, is(not(c)));
+        assertThat(b, is(not(c)));
+
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        ConfigSet configSet = new ConfigSet();
+        AppConfig.Builder a0builder = new AppConfig.Builder().message("A message, 0").times(88);
+        configSet.addBuilder("app/0", a0builder);
+        AppConfig.Builder a1builder = new AppConfig.Builder().message("A message, 1").times(89);
+        configSet.addBuilder("app/1", a1builder);
+
+        ConfigSubscription<AppConfig> c1 = ConfigSubscription.get(
+                new ConfigKey<>(AppConfig.class, "app/0"),
+                subscriber,
+                configSet,
+                new TimingValues());
+        ConfigSubscription<AppConfig> c2 = ConfigSubscription.get(
+                new ConfigKey<>(AppConfig.class, "app/1"),
+                subscriber,
+                configSet,
+                new TimingValues());
+
+        assertTrue(c1.equals(c1));
+        assertFalse(c1.equals(c2));
+    }
+
+    @Test
+    public void testSubscribeInterface() {
+        ConfigSubscriber sub = new ConfigSubscriber();
+        ConfigHandle<SimpletypesConfig> handle = sub.subscribe(SimpletypesConfig.class, "raw:boolval true", 10000);
+        assertNotNull(handle);
+        sub.nextConfig();
+        assertThat(handle.getConfig().boolval(), is(true));
+        //assertTrue(sub.getSource() instanceof RawSource);
+    }
+
+    // Test that subscription is closed and subscriptionHandles is empty if we get an exception (only the last is possible to
+    // test right now).
+    @Test
+    @Ignore
+    public void testSubscribeWithException() {
+        TestConfigSubscriber sub = new TestConfigSubscriber();
+        ConfigSourceSet configSourceSet = new ConfigSourceSet(Collections.singletonList("tcp/localhost:99999"));
+        try {
+            sub.subscribe(SimpletypesConfig.class, "configid", configSourceSet, new TimingValues().setSubscribeTimeout(100));
+            fail();
+        } catch (ConfigurationRuntimeException e) {
+            assertThat(sub.getSubscriptionHandles().size(), is(0));
+        }
+    }
+
+    private static class TestConfigSubscriber extends ConfigSubscriber {
+        List<ConfigHandle<? extends ConfigInstance>> getSubscriptionHandles() {
+            return subscriptionHandles;
+        }
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/ConfigURITest.java b/config/src/test/java/com/yahoo/config/subscription/ConfigURITest.java
new file mode 100644
index 00000000000..15cfff0448a
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/ConfigURITest.java
@@ -0,0 +1,46 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import org.junit.Test;
+
+import java.io.File;
+import java.io.IOException;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author lulf
+ * @since 5.1
+ */
+public class ConfigURITest {
+    @Test
+    public void testDefaultUri() {
+        ConfigURI uri = ConfigURI.createFromId("foo");
+        assertThat(uri.getConfigId(), is("foo"));
+        assertTrue(uri.getSource() instanceof ConfigSourceSet);
+    }
+
+    @Test
+    public void testFileUri() throws IOException {
+        File file = File.createTempFile("foo", ".cfg");
+        ConfigURI uri = ConfigURI.createFromId("file:" + file.getAbsolutePath());
+        assertThat(uri.getConfigId(), is(""));
+        assertTrue(uri.getSource() instanceof FileSource);
+    }
+
+    @Test
+    public void testDirUri() throws IOException {
+        ConfigURI uri = ConfigURI.createFromId("dir:.");
+        assertThat(uri.getConfigId(), is(""));
+        assertTrue(uri.getSource() instanceof DirSource);
+    }
+
+    @Test
+    public void testCustomUri() {
+        ConfigURI uri = ConfigURI.createFromIdAndSource("foo", new ConfigSet());
+        assertThat(uri.getConfigId(), is("foo"));
+        assertTrue(uri.getSource() instanceof ConfigSet);
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/DefaultConfigTest.java b/config/src/test/java/com/yahoo/config/subscription/DefaultConfigTest.java
new file mode 100644
index 00000000000..55b1eb97bee
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/DefaultConfigTest.java
@@ -0,0 +1,66 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.foo.*;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * Tests reading of a config containing
+ * <ul>
+ * <li>Missing values
+ * <li>Default values
+ * </ul>
+ * <p/>
+ * for
+ * <p/>
+ * <ul>
+ * <li>String and
+ * <li>Reference
+ * </ul>
+ *
+ * @author <a href="mailto:musum@yahoo-inc.com">Harald Musum</a>
+ */
+public class DefaultConfigTest {
+    static final String CONFIG_ID = "raw:" +
+            "nondefaultstring ####-------missing--------\n" +
+            "defaultstring \"thedefault\"\n" +
+            "nondefaultreference ####-------missing--------\n" +
+            "defaultreference \"thedefault\"\n";
+
+    @Test(expected = IllegalArgumentException.class)
+    public void testFailUponUnitializedValue() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        subscriber.subscribe(DefaulttestConfig.class, "raw:" +
+                "defaultstring \"new value\"");
+        subscriber.nextConfig();
+        subscriber.close();
+    }
+
+    /**
+     * Reads a config from a string which is exactly like one returned from
+     * the config server given only default values for this config.
+     * The parsing code is the same whether the reading happens from string
+     * or from a server connection, so this tests that this config can be
+     * received correctly from the server
+     */
+    @Test
+    public void testDefaultConfig() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        ConfigHandle<DefaulttestConfig> h = subscriber.subscribe(DefaulttestConfig.class, CONFIG_ID);
+        assertTrue(subscriber.nextConfig());
+        DefaulttestConfig config = h.getConfig();
+        verifyConfigValues(config);
+        subscriber.close();
+    }
+
+    private static void verifyConfigValues(DefaulttestConfig config) {
+        assertEquals("####-------missing--------", config.nondefaultstring());
+        assertEquals("thedefault", config.defaultstring());
+        assertEquals("####-------missing--------", config.nondefaultreference());
+        assertEquals("thedefault", config.defaultreference());
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/FunctionTest.java b/config/src/test/java/com/yahoo/config/subscription/FunctionTest.java
new file mode 100644
index 00000000000..8936c62784b
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/FunctionTest.java
@@ -0,0 +1,259 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.foo.FunctionTestConfig;
+
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.BufferedReader;
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNull;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
+
+
+/**
+ * Test most data types and features of the config client API,
+ * e.g. parameter access, missing default values, and more.
+ * <p/>
+ * NOTE: this test does NOT test null default values.
+ *
+ * @author gjoranv
+ */
+public class FunctionTest {
+
+    public static final String PATH = "src/test/resources/configs/function-test/";
+
+    private FunctionTestConfig config;
+    private ConfigSourceSet sourceSet = new ConfigSourceSet("function-test");
+
+    public void configure(FunctionTestConfig config, ConfigSourceSet sourceSet) {
+        this.config = config;
+        assertEquals(this.sourceSet, sourceSet);
+    }
+
+    @Before
+    public void resetConfig() {
+        config = null;
+    }
+
+    @Test
+    public void testVariableAccess() {
+        assertNull(config);
+        String configId = "file:" + PATH + "variableaccess.txt";
+        ConfigGetter<FunctionTestConfig> getter = new ConfigGetter<>(FunctionTestConfig.class);
+        assertVariableAccessValues(getter.getConfig(configId), configId);
+    }
+
+    @Test
+    public void testDefaultValues() {
+        assertNull(config);
+        String configId = "file:" + PATH + "defaultvalues.txt";
+        ConfigGetter<FunctionTestConfig> getter = new ConfigGetter<>(FunctionTestConfig.class);
+        FunctionTestConfig config = getter.getConfig(configId);
+
+        assertFalse(config.bool_val());
+        assertFalse(config.bool_with_def());
+        assertEquals(5, config.int_val());
+        assertEquals(-545, config.int_with_def());
+        assertEquals(1234567890123L, config.long_val());
+        assertEquals(-50000000000L, config.long_with_def());
+        assertEquals(41.23, config.double_val(), 0.000001);
+        assertEquals(-6.43, config.double_with_def(), 0.000001);
+        assertEquals("foo", config.string_val());
+        assertEquals("foobar", config.stringwithdef());
+        assertEquals(FunctionTestConfig.Enum_val.FOOBAR, config.enum_val());
+        assertEquals(FunctionTestConfig.Enumwithdef.BAR2, config.enumwithdef());
+        assertEquals(configId, config.refval());
+        assertEquals(configId, config.refwithdef());
+        assertEquals("vespa.log", config.fileVal().value());
+        assertEquals(1, config.boolarr().size());
+        assertEquals(0, config.intarr().size());
+        assertEquals(0, config.longarr().size());
+        assertEquals(2, config.doublearr().size());
+        assertEquals(1, config.stringarr().size());
+        assertEquals(1, config.enumarr().size());
+        assertEquals(0, config.refarr().size());
+        assertEquals(0, config.fileArr().size());
+
+        assertEquals(3, config.basicStruct().bar());
+        assertEquals(1, config.basicStruct().intArr().size());
+        assertEquals(10, config.basicStruct().intArr(0));
+        assertEquals(11, config.rootStruct().inner0().index());
+        assertEquals(12, config.rootStruct().inner1().index());
+
+        assertEquals(2, config.myarray().size());
+        assertEquals(1, config.myarray(0).myStruct().a());
+        assertEquals(-1, config.myarray(1).myStruct().a());
+        assertEquals("command.com", config.myarray(0).fileVal().value());
+        assertEquals("display.sys", config.myarray(1).fileVal().value());
+    }
+
+
+    @Test
+    public void testRandomOrder() {
+        assertNull(config);
+        String configId = "file:" + PATH + "randomorder.txt";
+        ConfigGetter<FunctionTestConfig> getter = new ConfigGetter<>(FunctionTestConfig.class);
+        FunctionTestConfig config = getter.getConfig(configId);
+        assertFalse(config.bool_val());
+        assertTrue(config.bool_with_def());
+        assertEquals(5, config.int_val());
+        assertEquals(-14, config.int_with_def());
+        assertEquals(666000666000L, config.long_val());
+        assertEquals(-333000333000L, config.long_with_def());
+        assertEquals(41.23, config.double_val(), 0.000001);
+        assertEquals(-12, config.double_with_def(), 0.000001);
+        assertEquals("foo", config.string_val());
+        assertEquals("bar and foo", config.stringwithdef());
+        assertEquals(FunctionTestConfig.Enum_val.FOOBAR, config.enum_val());
+        assertEquals(FunctionTestConfig.Enumwithdef.BAR2, config.enumwithdef());
+        assertEquals(configId, config.refval());
+        assertEquals(configId, config.refwithdef());
+        assertEquals("autoexec.bat", config.fileVal().value());
+        assertEquals(1, config.boolarr().size());
+        assertEquals(0, config.intarr().size());
+        assertEquals(0, config.longarr().size());
+        assertEquals(2, config.doublearr().size());
+        assertEquals(1, config.stringarr().size());
+        assertEquals(1, config.enumarr().size());
+        assertEquals(0, config.refarr().size());
+        assertEquals(0, config.fileArr().size());
+        assertEquals(2, config.myarray().size());
+    }
+
+    @Test
+    public void testLackingDefaults() throws IOException {
+        attemptLacking("bool_val", false);
+        attemptLacking("int_val", false);
+        attemptLacking("long_val", false);
+        attemptLacking("double_val", false);
+        attemptLacking("string_val", false);
+        attemptLacking("enum_val", false);
+        attemptLacking("refval", false);
+        attemptLacking("fileVal", false);
+
+        attemptLacking("boolarr", true);
+        attemptLacking("intarr", true);
+        attemptLacking("longarr", true);
+        attemptLacking("doublearr", true);
+        attemptLacking("enumarr", true);
+        attemptLacking("stringarr", true);
+        attemptLacking("refarr", true);
+        attemptLacking("fileArr", true);
+        attemptLacking("myarray", true);
+
+        attemptLacking("basicStruct.bar", false);
+        attemptLacking("rootStruct.inner0.index", false);
+        attemptLacking("rootStruct.inner1.index", false);
+//        attemptLacking("rootStruct.innerArr[0].stringVal", false);
+
+        attemptLacking("myarray[0].stringval", true);
+        attemptLacking("myarray[0].refval", false);
+        attemptLacking("myarray[0].anotherarray", true);
+        attemptLacking("myarray[0].anotherarray", true);
+        attemptLacking("myarray[0].myStruct.a", false);
+    }
+
+    private void attemptLacking(String param, boolean isArray) throws IOException {
+        BufferedReader in = new BufferedReader(new FileReader(new File(PATH + "defaultvalues.txt")));
+        StringBuilder config = new StringBuilder();
+        String line;
+        while ((line = in.readLine()) != null) {
+            if ((line.length() > param.length()) &&
+                    param.equals(line.substring(0, param.length())) &&
+                    (line.charAt(param.length()) == ' ' || line.charAt(param.length()) == '[')) {
+                // Ignore values matched
+            } else {
+                config.append(line).append("\n");
+            }
+        }
+        //System.out.println("Config lacking " + param + "-> " + config + "\n");
+        try {
+            ConfigGetter<FunctionTestConfig> getter = new ConfigGetter<FunctionTestConfig>(FunctionTestConfig.class);
+            getter.getConfig("raw:\n" + config);
+            if (isArray) {
+                // Arrays are empty by default
+                return;
+            }
+            fail("Expected to fail when not specifying value " + param + " without default");
+        } catch (IllegalArgumentException expected) {
+            if (isArray) {
+                fail("Arrays should be empty by default.");
+            }
+        }
+    }
+
+    public static void assertVariableAccessValues(FunctionTestConfig config, String configId) {
+        assertTrue(config.bool_with_def());
+        assertEquals(5, config.int_val());
+        assertEquals(-14, config.int_with_def());
+        assertEquals(12345678901L, config.long_val());
+        assertEquals(-9876543210L, config.long_with_def());
+        assertEquals(41.23, config.double_val(), 0.000001);
+        assertEquals(-12, config.double_with_def(), 0.000001);
+        assertEquals("foo", config.string_val());
+        assertEquals("bar and foo", config.stringwithdef());
+        assertEquals(FunctionTestConfig.Enum_val.FOOBAR, config.enum_val());
+        assertEquals(FunctionTestConfig.Enumwithdef.BAR2, config.enumwithdef());
+        assertEquals(configId, config.refval());
+        assertEquals(configId, config.refwithdef());
+        assertEquals("etc", config.fileVal().value());
+        assertEquals(1, config.boolarr().size());
+        assertEquals(1, config.boolarr().size());  // new api with accessor for a List of the original Java type
+        assertEquals(false, config.boolarr().get(0));  // new List api
+        assertEquals(false, config.boolarr(0));        // short-hand
+        assertEquals(0, config.intarr().size());
+        assertEquals(2, config.longarr().size());
+        assertEquals(Long.MAX_VALUE, config.longarr(0));
+        assertThat(config.longarr().get(1), is(Long.MIN_VALUE));
+        assertEquals(2, config.doublearr().size());
+        assertEquals(1, config.stringarr().size());
+        assertEquals(1, config.enumarr().size());
+        assertEquals(FunctionTestConfig.Enumarr.VALUES, config.enumarr().get(0));  // new List api, don't have to call value()
+        assertEquals(3, config.refarr().size());
+        assertEquals(1, config.fileArr().size());
+        assertEquals(configId, config.refarr(0));
+        assertEquals(":parent", config.refarr(1));
+        assertEquals("parent:", config.refarr(2));
+        assertEquals("bin", config.fileArr(0).value());
+        assertEquals("pom.xml", config.pathArr(0).toString());
+        assertEquals("pom.xml", config.pathMap("one").toString());
+
+        assertEquals("basicFoo", config.basicStruct().foo());
+        assertEquals(3, config.basicStruct().bar());  // new List api
+        assertEquals(2, config.basicStruct().intArr().size());
+        assertThat(config.basicStruct().intArr().get(0), is(310));  // new List api
+        assertThat(config.basicStruct().intArr().get(1), is(311));  // new List api
+        assertEquals(310, config.basicStruct().intArr(0));          // short-hand
+        assertEquals("inner0", config.rootStruct().inner0().name());  // new List api
+        assertEquals(11, config.rootStruct().inner0().index());
+        assertEquals("inner1", config.rootStruct().inner1().name());
+        assertEquals(12, config.rootStruct().inner1().index());
+        assertEquals(2, config.rootStruct().innerArr().size());
+        assertEquals(true, config.rootStruct().innerArr(0).boolVal());
+        assertEquals("deep", config.rootStruct().innerArr(0).stringVal());
+        assertEquals(false, config.rootStruct().innerArr(1).boolVal());
+        assertEquals("blue a=\"escaped\"", config.rootStruct().innerArr(1).stringVal());
+
+        assertEquals(2, config.myarray().size());  // new List api
+        assertEquals(configId, config.myarray().get(0).refval());    // new List api
+        assertEquals(configId, config.myarray(0).refval());          // short-hand
+        assertEquals("file0", config.myarray(0).fileVal().value());
+        assertEquals(1, config.myarray(0).myStruct().a());
+        assertEquals(2, config.myarray(0).myStruct().b());
+        assertEquals(configId, config.myarray(1).refval());
+        assertEquals("file1", config.myarray(1).fileVal().value());
+        assertEquals(-1, config.myarray(1).myStruct().a());
+        assertEquals(-2, config.myarray(1).myStruct().b());
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/GenericConfigSubscriberTest.java b/config/src/test/java/com/yahoo/config/subscription/GenericConfigSubscriberTest.java
new file mode 100644
index 00000000000..26b47f7621c
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/GenericConfigSubscriberTest.java
@@ -0,0 +1,75 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import java.util.*;
+
+import com.yahoo.config.subscription.impl.GenericConfigHandle;
+import com.yahoo.config.subscription.impl.GenericConfigSubscriber;
+import com.yahoo.config.subscription.impl.JRTConfigRequester;
+import com.yahoo.config.subscription.impl.JRTConfigRequesterTest;
+import com.yahoo.config.subscription.impl.MockConnection;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.JRTConnectionPool;
+import com.yahoo.vespa.config.protocol.CompressionType;
+import org.junit.Test;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.*;
+
+/**
+ *
+ * Test cases for the "generic" (class-less) subscription mechanism.
+ *
+ * @author lulf
+ * @since 5.1
+ */
+public class GenericConfigSubscriberTest {
+
+    @Test
+    public void testSubscribeGeneric() {
+        Map<ConfigSourceSet, JRTConfigRequester> requesters = new HashMap<>();
+        ConfigSourceSet sourceSet = new ConfigSourceSet("blabla");
+        requesters.put(sourceSet, JRTConfigRequester.get(new MockConnection(), JRTConfigRequesterTest.getTestTimingValues()));
+        GenericConfigSubscriber sub = new GenericConfigSubscriber(requesters);
+        final List<String> defContent = Arrays.asList("myVal int");
+        GenericConfigHandle handle = sub.subscribe(new ConfigKey<>("simpletypes", "id", "config"), defContent, sourceSet, JRTConfigRequesterTest.getTestTimingValues());
+        assertTrue(sub.nextConfig());
+        assertTrue(handle.isChanged());
+        assertThat(handle.getRawConfig().getPayload().withCompression(CompressionType.UNCOMPRESSED).toString(), is("{}")); // MockConnection returns empty string
+        assertFalse(sub.nextConfig());
+        assertFalse(handle.isChanged());
+    }
+
+    @Test
+    public void testGenericRequesterPooling() {
+        ConfigSourceSet source1 = new ConfigSourceSet("tcp/foo:78");
+        ConfigSourceSet source2 = new ConfigSourceSet("tcp/bar:79");
+        JRTConfigRequester req1 = JRTConfigRequester.get(new JRTConnectionPool(source1), JRTConfigRequesterTest.getTestTimingValues());
+        JRTConfigRequester req2 = JRTConfigRequester.get(new JRTConnectionPool(source2), JRTConfigRequesterTest.getTestTimingValues());
+        Map<ConfigSourceSet, JRTConfigRequester> requesters = new LinkedHashMap<>();
+        requesters.put(source1, req1);
+        requesters.put(source2, req2);
+        GenericConfigSubscriber sub = new GenericConfigSubscriber(requesters);
+        assertEquals(sub.requesters().get(source1).getConnectionPool().getCurrent().getAddress(), "tcp/foo:78");
+        assertEquals(sub.requesters().get(source2).getConnectionPool().getCurrent().getAddress(), "tcp/bar:79");
+
+    }
+
+    @Test(expected=UnsupportedOperationException.class)
+    public void testOverriddenSubscribeInvalid1() {
+        GenericConfigSubscriber sub = new GenericConfigSubscriber();
+        sub.subscribe(null, null);
+    }
+
+    @Test(expected=UnsupportedOperationException.class)
+    public void testOverriddenSubscribeInvalid2() {
+        GenericConfigSubscriber sub = new GenericConfigSubscriber();
+        sub.subscribe(null, null, 0l);
+    }
+
+    @Test(expected=UnsupportedOperationException.class)
+    public void testOverriddenSubscribeInvalid3() {
+        GenericConfigSubscriber sub = new GenericConfigSubscriber();
+        sub.subscribe(null, null, "");
+    }
+}
\ No newline at end of file
diff --git a/config/src/test/java/com/yahoo/config/subscription/NamespaceTest.java b/config/src/test/java/com/yahoo/config/subscription/NamespaceTest.java
new file mode 100644
index 00000000000..90be475bb94
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/NamespaceTest.java
@@ -0,0 +1,19 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.myproject.config.NamespaceConfig;
+import org.junit.Test;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author gjoranv
+ */
+public class NamespaceTest {
+    @Test
+    public void verifyConfigClassWithExplicitNamespace() {
+        NamespaceConfig config = new ConfigGetter<>(NamespaceConfig.class).getConfig("raw: a 0\n");
+        assertThat(config.a(), is(0));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/UnicodeTest.java b/config/src/test/java/com/yahoo/config/subscription/UnicodeTest.java
new file mode 100644
index 00000000000..355c94e03b6
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/UnicodeTest.java
@@ -0,0 +1,31 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription;
+
+import com.yahoo.foo.UnicodeConfig;
+import org.junit.Test;
+
+import static org.junit.Assert.assertEquals;
+
+/**
+ * Tests reading of a config containing unicode characters in UTF-8
+ *
+ * @author Vidar Larsen
+ * @author Harald Musum
+ */
+public class UnicodeTest {
+    /**
+     * Reads a config from a file which is exactly like one returned from
+     * the config server given only default values for this config.
+     * The parsing code is the same whether the reading happens from file
+     * or from a server connection, so this tests that this config can be
+     * received correctly from the server
+     */
+    @Test
+    public void testUnicodeConfigReading() {
+        ConfigGetter<UnicodeConfig> getter = new ConfigGetter<>(UnicodeConfig.class);
+        UnicodeConfig config = getter.getConfig("file:src/test/resources/configs/unicode/unicode.cfg");
+
+        assertEquals("Hei \u00E6\u00F8\u00E5 \uBC14\uB451 \u00C6\u00D8\u00C5 hallo", config.unicodestring1());
+        assertEquals("abc \u00E6\u00F8\u00E5 \u56F2\u7881 \u00C6\u00D8\u00C5 ABC", config.unicodestring2());
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/impl/FileConfigSubscriptionTest.java b/config/src/test/java/com/yahoo/config/subscription/impl/FileConfigSubscriptionTest.java
new file mode 100644
index 00000000000..ce9323f0ec7
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/impl/FileConfigSubscriptionTest.java
@@ -0,0 +1,105 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription.impl;
+
+import com.yahoo.config.ConfigurationRuntimeException;
+import com.yahoo.foo.SimpletypesConfig;
+import com.yahoo.foo.TestReferenceConfig;
+import com.yahoo.config.subscription.ConfigSubscriber;
+import com.yahoo.config.subscription.DirSource;
+import com.yahoo.config.subscription.FileSource;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.TimingValues;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.File;
+import java.io.FileWriter;
+import java.io.IOException;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author lulf
+ * @since 5.1.7
+ */
+public class FileConfigSubscriptionTest {
+    private File TEST_TYPES_FILE;
+
+    @Before
+    public void setUp() throws IOException {
+       TEST_TYPES_FILE = File.createTempFile("fooconfig", ".cfg");
+    }
+
+    private void writeConfig(String field, String value) throws IOException {
+        FileWriter writer = new FileWriter(TEST_TYPES_FILE);
+        writer.write(field + " " + value);
+        writer.close();
+    }
+
+    @Test
+    public void require_that_new_config_is_detected_in_time() throws IOException, InterruptedException {
+        writeConfig("intval", "23");
+        ConfigSubscriber subscriber = new ConfigSubscriber(new FileSource(TEST_TYPES_FILE));
+        ConfigSubscription<SimpletypesConfig> sub = new FileConfigSubscription<>(
+                new ConfigKey<>(SimpletypesConfig.class, ""),
+                subscriber,
+                TEST_TYPES_FILE);
+        assertTrue(sub.nextConfig(1000));
+        assertThat(sub.config.intval(), is(23));
+        Thread.sleep(1000);
+        writeConfig("intval", "33");
+        assertTrue(sub.nextConfig(1000));
+        assertThat(sub.config.intval(), is(33));
+    }
+
+    @Test
+    public void require_that_new_config_is_detected_on_reload() throws IOException {
+        writeConfig("intval", "23");
+        ConfigSubscriber subscriber = new ConfigSubscriber(new FileSource(TEST_TYPES_FILE));
+        ConfigSubscription<SimpletypesConfig> sub = new FileConfigSubscription<>(
+                new ConfigKey<>(SimpletypesConfig.class, ""),
+                subscriber,
+                TEST_TYPES_FILE);
+        assertTrue(sub.nextConfig(1000));
+        assertThat(sub.config.intval(), is(23));
+        writeConfig("intval", "33");
+        sub.reload(1);
+        assertTrue(sub.nextConfig(1000));
+        assertThat(sub.config.intval(), is(33));
+        assertTrue(sub.isConfigChanged());
+        assertTrue(sub.isGenerationChanged());
+        sub.reload(2);
+        assertTrue(sub.nextConfig(1000));
+        assertThat(sub.config.intval(), is(33));
+        assertFalse(sub.isConfigChanged());
+        assertTrue(sub.isGenerationChanged());
+    }
+
+    @Test
+    public void require_that_dir_config_id_reference_is_not_changed() {
+        final String cfgDir = "src/test/resources/configs/foo";
+        final String cfgId = "dir:" + cfgDir;
+        final ConfigKey<TestReferenceConfig> key = new ConfigKey<>(TestReferenceConfig.class, cfgId);
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        ConfigSubscription<TestReferenceConfig> sub = ConfigSubscription.get(key, subscriber, new DirSource(new File(cfgDir)), new TimingValues());
+        assertTrue(sub.nextConfig(1000));
+        assertThat(sub.config.configId(), is(cfgId));
+    }
+
+    @Test(expected = ConfigurationRuntimeException.class)
+    public void require_that_bad_file_throws_exception() throws IOException {
+        // A little trick to ensure that we can create the subscriber, but that we get an error when reading.
+        writeConfig("intval", "23");
+        ConfigSubscriber subscriber = new ConfigSubscriber(new FileSource(TEST_TYPES_FILE));
+        ConfigSubscription<SimpletypesConfig> sub = new FileConfigSubscription<>(
+                new ConfigKey<>(SimpletypesConfig.class, ""),
+                subscriber,
+                TEST_TYPES_FILE);
+        sub.reload(1);
+        assertTrue(TEST_TYPES_FILE.setReadable(false));
+        sub.nextConfig(0);
+    }
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/impl/JRTConfigRequesterTest.java b/config/src/test/java/com/yahoo/config/subscription/impl/JRTConfigRequesterTest.java
new file mode 100644
index 00000000000..7d3b86db2fe
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/impl/JRTConfigRequesterTest.java
@@ -0,0 +1,356 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription.impl;
+
+import com.yahoo.foo.SimpletypesConfig;
+import com.yahoo.config.subscription.ConfigSubscriber;
+import com.yahoo.jrt.Request;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.ErrorCode;
+import com.yahoo.vespa.config.ErrorType;
+import com.yahoo.vespa.config.TimingValues;
+import com.yahoo.vespa.config.protocol.JRTServerConfigRequestV3;
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Random;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author <a href="mailto:musum@yahoo-inc.com">Harald Musum</a>
+ * @since 5.1.11
+ */
+public class JRTConfigRequesterTest {
+
+    @Test
+    public void testDelayCalculation() {
+        TimingValues defaultTimingValues = new TimingValues();
+        Random random = new Random(0); // Use seed to make tests predictable
+        TimingValues timingValues = new TimingValues(defaultTimingValues, random);
+
+        // transientFailures and fatalFailures are not set until after delay has been calculated,
+        // so 0 is the case for the first failure
+        int transientFailures = 0;
+        int fatalFailures = 0;
+        boolean configured = false;
+
+        // First time failure, not configured
+        long delay = JRTConfigRequester.calculateFailedRequestDelay(ErrorType.TRANSIENT,
+                transientFailures, fatalFailures, timingValues, configured);
+        assertThat(delay, is(timingValues.getUnconfiguredDelay()));
+        transientFailures = 5;
+        delay = JRTConfigRequester.calculateFailedRequestDelay(ErrorType.TRANSIENT,
+                transientFailures, fatalFailures, timingValues, configured);
+        assertThat(delay, is((transientFailures + 1) * timingValues.getUnconfiguredDelay()));
+        transientFailures = 0;
+
+
+        delay = JRTConfigRequester.calculateFailedRequestDelay(ErrorType.FATAL,
+                transientFailures, fatalFailures, timingValues, configured);
+        assertTrue(delay > (1 - JRTConfigRequester.randomFraction) * timingValues.getFixedDelay());
+        assertTrue(delay < (1 + JRTConfigRequester.randomFraction) * timingValues.getFixedDelay());
+        assertThat(delay, is(5462L));
+
+        // First time failure, configured
+        configured = true;
+
+        delay = JRTConfigRequester.calculateFailedRequestDelay(ErrorType.TRANSIENT,
+                transientFailures, fatalFailures, timingValues, configured);
+        assertThat(delay, is(timingValues.getConfiguredErrorDelay()));
+
+        delay = JRTConfigRequester.calculateFailedRequestDelay(ErrorType.FATAL,
+                transientFailures, fatalFailures, timingValues, configured);
+        assertTrue(delay > (1 - JRTConfigRequester.randomFraction) * timingValues.getFixedDelay());
+        assertTrue(delay < (1 + JRTConfigRequester.randomFraction) * timingValues.getFixedDelay());
+        assertThat(delay, is(5663L));
+
+
+        // nth time failure, not configured
+        fatalFailures = 1;
+        configured = false;
+        delay = JRTConfigRequester.calculateFailedRequestDelay(ErrorType.TRANSIENT,
+                transientFailures, fatalFailures, timingValues, configured);
+        assertThat(delay, is(timingValues.getUnconfiguredDelay()));
+        delay = JRTConfigRequester.calculateFailedRequestDelay(ErrorType.FATAL,
+                transientFailures, fatalFailures, timingValues, configured);
+        final long l = timingValues.getFixedDelay() + timingValues.getUnconfiguredDelay();
+        assertTrue(delay > (1 - JRTConfigRequester.randomFraction) * l);
+        assertTrue(delay < (1 + JRTConfigRequester.randomFraction) * l);
+        assertThat(delay, is(5377L));
+
+
+        // nth time failure, configured
+        fatalFailures = 1;
+        configured = true;
+        delay = JRTConfigRequester.calculateFailedRequestDelay(ErrorType.TRANSIENT,
+                transientFailures, fatalFailures, timingValues, configured);
+        assertThat(delay, is(timingValues.getConfiguredErrorDelay()));
+        delay = JRTConfigRequester.calculateFailedRequestDelay(ErrorType.FATAL,
+                transientFailures, fatalFailures, timingValues, configured);
+        final long l1 = timingValues.getFixedDelay() + timingValues.getConfiguredErrorDelay();
+        assertTrue(delay > (1 - JRTConfigRequester.randomFraction) * l1);
+        assertTrue(delay < (1 + JRTConfigRequester.randomFraction) * l1);
+        assertThat(delay, is(20851L));
+
+
+        // 1 more than max delay multiplier time failure, configured
+        fatalFailures = timingValues.getMaxDelayMultiplier() + 1;
+        configured = true;
+        delay = JRTConfigRequester.calculateFailedRequestDelay(ErrorType.TRANSIENT,
+                transientFailures, fatalFailures, timingValues, configured);
+        assertThat(delay, is(timingValues.getConfiguredErrorDelay()));
+        assertTrue(delay < timingValues.getMaxDelayMultiplier() * timingValues.getConfiguredErrorDelay());
+        delay = JRTConfigRequester.calculateFailedRequestDelay(ErrorType.FATAL,
+                transientFailures, fatalFailures, timingValues, configured);
+        final long l2 = timingValues.getFixedDelay() + timingValues.getMaxDelayMultiplier() * timingValues.getConfiguredErrorDelay();
+        assertTrue(delay > (1 - JRTConfigRequester.randomFraction) * l2);
+        assertTrue(delay < (1 + JRTConfigRequester.randomFraction) * l2);
+        assertThat(delay, is(163520L));
+    }
+
+    @Test
+    public void testDelay() {
+        TimingValues timingValues = new TimingValues();
+
+        // transientFailures and fatalFailures are not set until after delay has been calculated,
+        // so 0 is the case for the first failure
+        int transientFailures = 0;
+        int fatalFailures = 0;
+
+        // First time failure, configured
+        long delay = JRTConfigRequester.calculateFailedRequestDelay(ErrorType.TRANSIENT,
+                transientFailures, fatalFailures, timingValues, true);
+        assertThat(delay, is(timingValues.getConfiguredErrorDelay()));
+        assertThat(delay, is((transientFailures + 1) * timingValues.getConfiguredErrorDelay()));
+    }
+
+    @Test
+    public void testErrorTypes() {
+        List<Integer> transientErrors = Arrays.asList(com.yahoo.jrt.ErrorCode.CONNECTION, com.yahoo.jrt.ErrorCode.TIMEOUT);
+        List<Integer> fatalErrors = Arrays.asList(ErrorCode.UNKNOWN_CONFIG, ErrorCode.UNKNOWN_DEFINITION, ErrorCode.OUTDATED_CONFIG,
+                ErrorCode.UNKNOWN_DEF_MD5, ErrorCode.ILLEGAL_NAME, ErrorCode.ILLEGAL_VERSION, ErrorCode.ILLEGAL_CONFIGID,
+                ErrorCode.ILLEGAL_DEF_MD5, ErrorCode.ILLEGAL_CONFIG_MD5, ErrorCode.ILLEGAL_TIMEOUT, ErrorCode.INTERNAL_ERROR,
+                9999); // unknown should also be fatal
+        for (Integer i : transientErrors) {
+            assertThat(ErrorType.getErrorType(i), is(ErrorType.TRANSIENT));
+        }
+        for (Integer i : fatalErrors) {
+            assertThat(ErrorType.getErrorType(i), is(ErrorType.FATAL));
+        }
+    }
+
+    @Test
+    public void testFirstRequestAfterSubscribing() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        final TimingValues timingValues = getTestTimingValues();
+        JRTConfigSubscription<SimpletypesConfig> sub = createSubscription(subscriber, timingValues);
+
+        final MockConnection connection = new MockConnection();
+        JRTConfigRequester requester = new JRTConfigRequester(connection, timingValues);
+        assertThat(requester.getConnectionPool(), is(connection));
+        requester.request(sub);
+        final Request request = connection.getRequest();
+        assertNotNull(request);
+        assertThat(connection.getNumberOfRequests(), is(1));
+        JRTServerConfigRequestV3 receivedRequest = JRTServerConfigRequestV3.createFromRequest(request);
+        assertTrue(receivedRequest.validateParameters());
+        assertThat(receivedRequest.getTimeout(), is(timingValues.getSubscribeTimeout()));
+        assertThat(requester.getFatalFailures(), is(0));
+        assertThat(requester.getTransientFailures(), is(0));
+    }
+
+    @Test
+    public void testFatalError() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        final TimingValues timingValues = getTestTimingValues();
+
+        final MockConnection connection = new MockConnection(new ErrorResponseHandler());
+        JRTConfigRequester requester = new JRTConfigRequester(connection, timingValues);
+        requester.request(createSubscription(subscriber, timingValues));
+        waitUntilResponse(connection);
+        assertThat(requester.getFatalFailures(), is(1));
+        assertThat(requester.getTransientFailures(), is(0));
+    }
+
+    @Test
+    public void testFatalErrorSubscribed() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        final TimingValues timingValues = getTestTimingValues();
+        JRTConfigSubscription<SimpletypesConfig> sub = createSubscription(subscriber, timingValues);
+        sub.setConfig(config());
+        sub.setGeneration(1L);
+
+        final MockConnection connection = new MockConnection(new ErrorResponseHandler());
+        JRTConfigRequester requester = new JRTConfigRequester(connection, timingValues);
+        requester.request(sub);
+        waitUntilResponse(connection);
+        assertThat(requester.getFatalFailures(), is(1));
+        assertThat(requester.getTransientFailures(), is(0));
+    }
+
+    @Test
+    public void testTransientError() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        final TimingValues timingValues = getTestTimingValues();
+
+        final MockConnection connection = new MockConnection(new ErrorResponseHandler(com.yahoo.jrt.ErrorCode.TIMEOUT));
+        JRTConfigRequester requester = new JRTConfigRequester(connection, timingValues);
+        requester.request(createSubscription(subscriber, timingValues));
+        waitUntilResponse(connection);
+        assertThat(requester.getFatalFailures(), is(0));
+        assertThat(requester.getTransientFailures(), is(1));
+    }
+
+    @Test
+    public void testTransientErrorSubscribed() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        final TimingValues timingValues = getTestTimingValues();
+        JRTConfigSubscription<SimpletypesConfig> sub = createSubscription(subscriber, timingValues);
+        sub.setConfig(config());
+        sub.setGeneration(1L);
+
+        final MockConnection connection = new MockConnection(new ErrorResponseHandler(com.yahoo.jrt.ErrorCode.TIMEOUT));
+        JRTConfigRequester requester = new JRTConfigRequester(connection, timingValues);
+        requester.request(sub);
+        waitUntilResponse(connection);
+        assertThat(requester.getFatalFailures(), is(0));
+        assertThat(requester.getTransientFailures(), is(1));
+    }
+
+    @Test
+    public void testUnknownConfigDefinitionError() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        final TimingValues timingValues = getTestTimingValues();
+        JRTConfigSubscription<SimpletypesConfig> sub = createSubscription(subscriber, timingValues);
+        sub.setConfig(config());
+        sub.setGeneration(1L);
+
+        final MockConnection connection = new MockConnection(new ErrorResponseHandler(ErrorCode.UNKNOWN_DEFINITION));
+        JRTConfigRequester requester = new JRTConfigRequester(connection, timingValues);
+        assertThat(requester.getConnectionPool(), is(connection));
+        requester.request(sub);
+        waitUntilResponse(connection);
+        assertThat(requester.getFatalFailures(), is(1));
+        assertThat(requester.getTransientFailures(), is(0));
+        // TODO Check that no further request was sent?
+    }
+
+    @Test
+    public void testClosedSubscription() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        final TimingValues timingValues = getTestTimingValues();
+        JRTConfigSubscription<SimpletypesConfig> sub = createSubscription(subscriber, timingValues);
+        sub.close();
+
+        final MockConnection connection = new MockConnection(new MockConnection.OKResponseHandler());
+        JRTConfigRequester requester = new JRTConfigRequester(connection, timingValues);
+        requester.request(sub);
+        assertThat(connection.getNumberOfRequests(), is(1));
+        // Check that no further request was sent?
+        try {
+            Thread.sleep(timingValues.getFixedDelay()*2);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+        assertThat(connection.getNumberOfRequests(), is(1));
+    }
+
+    @Test
+    public void testTimeout() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        final TimingValues timingValues = getTestTimingValues();
+        JRTConfigSubscription<SimpletypesConfig> sub = createSubscription(subscriber, timingValues);
+        sub.close();
+
+        final MockConnection connection = new MockConnection(
+                new DelayedResponseHandler(timingValues.getSubscribeTimeout()),
+                2); // fake that we have more than one source
+        JRTConfigRequester requester = new JRTConfigRequester(connection, timingValues);
+        requester.request(createSubscription(subscriber, timingValues));
+        // Check that no further request was sent?
+        try {
+            Thread.sleep(timingValues.getFixedDelay()*2);
+        } catch (InterruptedException e) {
+            e.printStackTrace();
+        }
+        assertTrue(connection.getNumberOfFailovers() >= 1);
+    }
+
+    private JRTConfigSubscription<SimpletypesConfig> createSubscription(ConfigSubscriber subscriber, TimingValues timingValues) {
+        return new JRTConfigSubscription<>(
+                new ConfigKey<>(SimpletypesConfig.class, "testid"), subscriber, null, timingValues);
+    }
+
+    private SimpletypesConfig config() {
+        SimpletypesConfig.Builder builder = new SimpletypesConfig.Builder();
+        return new SimpletypesConfig(builder);
+    }
+
+    private void waitUntilResponse(MockConnection connection) {
+        int i = 0;
+        while (i < 1000 && connection.getRequest() == null) {
+            try {
+                Thread.sleep(10);
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+            i++;
+        }
+    }
+
+    public static TimingValues getTestTimingValues() { return new TimingValues(
+            1000,  // successTimeout
+            500,   // errorTimeout
+            500,   // initialTimeout
+            2000,  // subscribeTimeout
+            250,   // unconfiguredDelay
+            500,   // configuredErrorDelay
+            250,   // fixedDelay
+            5);    // maxDelayMultiplier
+    }
+
+    private static class ErrorResponseHandler extends MockConnection.OKResponseHandler {
+        private final int errorCode;
+
+        public ErrorResponseHandler() {
+            this(ErrorCode.INTERNAL_ERROR);
+        }
+
+        public ErrorResponseHandler(int errorCode) {
+            this.errorCode = errorCode;
+        }
+
+        @Override
+        public void run() {
+            System.out.println("Running error response handler");
+            request().setError(errorCode, "error");
+            requestWaiter().handleRequestDone(request());
+        }
+    }
+
+    private static class DelayedResponseHandler extends MockConnection.OKResponseHandler {
+        private final long waitTimeMilliSeconds;
+
+        public DelayedResponseHandler(long waitTimeMilliSeconds) {
+            this.waitTimeMilliSeconds = waitTimeMilliSeconds;
+        }
+
+        @Override
+        public void run() {
+            System.out.println("Running delayed response handler (waiting " + waitTimeMilliSeconds +
+            ") before responding");
+            try {
+                Thread.sleep(waitTimeMilliSeconds);
+            } catch (InterruptedException e) {
+                e.printStackTrace();
+            }
+            request().setError(com.yahoo.jrt.ErrorCode.TIMEOUT, "error");
+            requestWaiter().handleRequestDone(request());
+        }
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/config/subscription/util/JsonHelper.java b/config/src/test/java/com/yahoo/config/subscription/util/JsonHelper.java
new file mode 100644
index 00000000000..27ac1a1278c
--- /dev/null
+++ b/config/src/test/java/com/yahoo/config/subscription/util/JsonHelper.java
@@ -0,0 +1,28 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.config.subscription.util;
+
+import com.google.common.base.Joiner;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static uk.co.datumedge.hamcrest.json.SameJSONAs.sameJSONAs;
+
+/**
+ * @author Vegard Sjonfjell
+ */
+public class JsonHelper {
+    /**
+     * Convenience method to input JSON without escaping double quotes and newlines
+     * Each parameter represents a line of JSON encoded data
+     * The lines are joined with newline and single quotes are replaced with double quotes
+     */
+    public static String inputJson(String... lines) {
+        return Joiner.on("\n").join(lines).replaceAll("'", "\"");
+    }
+
+    /**
+     * Structurally compare two JSON encoded strings
+     */
+    public static void assertJsonEquals(String inputJson, String expectedJson) {
+        assertThat(inputJson, sameJSONAs(expectedJson));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/ConfigBuilderMergeTest.java b/config/src/test/java/com/yahoo/vespa/config/ConfigBuilderMergeTest.java
new file mode 100644
index 00000000000..95ed049de6d
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/ConfigBuilderMergeTest.java
@@ -0,0 +1,120 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.foo.ArraytypesConfig;
+import com.yahoo.config.subscription.ConfigInstanceUtil;
+import com.yahoo.foo.SimpletypesConfig;
+import com.yahoo.foo.StructtypesConfig;
+import com.yahoo.foo.MaptypesConfig;
+import org.junit.Test;
+
+import java.util.Arrays;
+
+import static com.yahoo.foo.MaptypesConfig.Innermap;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * SEO keywords: test override() on builders. overrideTest, testOverride
+ *
+ * @author lulf
+ * @since 5.1
+ */
+public class ConfigBuilderMergeTest {
+
+    private SimpletypesConfig.Builder createSimpleBuilder(String s, int i, long l, double d, boolean b) {
+        SimpletypesConfig.Builder builder = new SimpletypesConfig.Builder();
+        builder.stringval(s);
+        builder.intval(i);
+        builder.longval(l);
+        builder.doubleval(d);
+        builder.boolval(b);
+        return builder;
+    }
+
+    private ArraytypesConfig.Builder createArrayBuilder(String [] strings) {
+        ArraytypesConfig.Builder builder = new ArraytypesConfig.Builder();
+        for (String str : strings) {
+            builder.stringarr(str);
+        }
+        return builder;
+    }
+
+    private StructtypesConfig.Builder createSimpleStructBuilder(String name, String gender, String [] emails) {
+        StructtypesConfig.Builder builder = new StructtypesConfig.Builder();
+        StructtypesConfig.Simple.Builder simpleBuilder = new StructtypesConfig.Simple.Builder();
+        simpleBuilder.name(name);
+        simpleBuilder.gender(StructtypesConfig.Simple.Gender.Enum.valueOf(gender));
+        simpleBuilder.emails(Arrays.asList(emails));
+        builder.simple(simpleBuilder);
+        return builder;
+    }
+
+    @Test
+    public void require_that_simple_fields_are_overwritten_on_merge() {
+        SimpletypesConfig.Builder b1 = createSimpleBuilder("foo", 2, 5, 4.3, false);
+        SimpletypesConfig.Builder b2 = createSimpleBuilder("bar", 3, 6, 3.3, true);
+        ConfigInstanceUtil.setValues(b1, b2);
+        SimpletypesConfig c1 = new SimpletypesConfig(b1);
+        SimpletypesConfig c2 = new SimpletypesConfig(b2);
+        assertThat(c1, is(c2));
+    }
+
+    @Test
+    public void require_that_arrays_are_appended_on_merge() {
+        ArraytypesConfig.Builder b1 = createArrayBuilder(new String[] { "foo", "bar" });
+        ArraytypesConfig.Builder b2 = createArrayBuilder(new String[] { "baz", "bim" });
+
+        ConfigInstanceUtil.setValues(b1, b2);
+        ArraytypesConfig c1 = new ArraytypesConfig(b1);
+        assertThat(c1.stringarr().size(), is(4));
+        assertThat(c1.stringarr(0), is("foo"));
+        assertThat(c1.stringarr(1), is("bar"));
+        assertThat(c1.stringarr(2), is("baz"));
+        assertThat(c1.stringarr(3), is("bim"));
+
+        ArraytypesConfig c2 = new ArraytypesConfig(b2);
+        assertThat(c2.stringarr(0), is("baz"));
+        assertThat(c2.stringarr(1), is("bim"));
+    }
+
+    @Test
+    public void require_that_struct_fields_are_overwritten() {
+        String name1 = "foo";
+        String gender1 = "MALE";
+        String emails1[] = { "foo@bar", "bar@foo" };
+        String name2 = "bar";
+        String gender2 = "FEMALE";
+        String emails2[] = { "foo@bar", "bar@foo" };
+        StructtypesConfig.Builder b1 = createSimpleStructBuilder(name1, gender1, emails1);
+        StructtypesConfig.Builder b2 = createSimpleStructBuilder(name2, gender2, emails2);
+        ConfigInstanceUtil.setValues(b1, b2);
+        StructtypesConfig c1 = new StructtypesConfig(b1);
+        assertThat(c1.simple().name(),  is(name2));
+        assertThat(c1.simple().gender().toString(),  is(gender2));
+        assertThat(c1.simple().emails(0), is(emails2[0]));
+        assertThat(c1.simple().emails(1), is(emails2[1]));
+    }
+
+    @Test
+    public void source_map_is_copied_into_destination_map_on_merge() {
+        MaptypesConfig.Builder destination = new MaptypesConfig.Builder()
+                .intmap("one", 1)
+                .innermap("first", new Innermap.Builder()
+                .foo(1));
+
+        MaptypesConfig.Builder source = new MaptypesConfig.Builder()
+                .intmap("two", 2)
+                .innermap("second", new Innermap.Builder()
+                .foo(2));
+
+        ConfigInstanceUtil.setValues(destination, source);
+
+        MaptypesConfig config = new MaptypesConfig(destination);
+        assertThat(config.intmap("one"), is(1));
+        assertThat(config.intmap("two"), is(2));
+        assertThat(config.innermap("first").foo(), is(1));
+        assertThat(config.innermap("second").foo(), is(2));
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/ConfigCacheKeyTest.java b/config/src/test/java/com/yahoo/vespa/config/ConfigCacheKeyTest.java
new file mode 100755
index 00000000000..5356acdfade
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/ConfigCacheKeyTest.java
@@ -0,0 +1,38 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import org.junit.Test;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.not;
+import static org.junit.Assert.*;
+
+/**
+ *
+ * @author <a href="musum@yahoo-inc.com">Harald Musum</a>
+ */
+public class ConfigCacheKeyTest {
+    @Test
+    public void testConfigCacheKey() {
+        final String defMd5 = "md5";
+        final String defMd5_2 = "md5_2";
+
+        ConfigCacheKey k1 = new ConfigCacheKey("foo", "id", "ns", defMd5);
+        ConfigCacheKey k2 = new ConfigCacheKey("foo", "id", "ns", defMd5);
+        ConfigCacheKey k3 = new ConfigCacheKey("foo", "id", "ns", defMd5_2);
+        ConfigCacheKey k4 = new ConfigCacheKey("foo", "id", "ns_1", defMd5);
+        ConfigCacheKey k5 = new ConfigCacheKey("foo", "id", "ns_1", null); // test with null defMd5
+        final ConfigKey<?> configKey = new ConfigKey<>("foo", "id", "ns");
+        ConfigCacheKey k1_2 = new ConfigCacheKey(configKey, defMd5);
+        assertTrue(k1.equals(k1));
+        assertTrue(k1.equals(k1_2));
+        assertTrue(k1.equals(k2));
+        assertFalse(k3.equals(k2));
+        assertFalse(k4.equals(k1));
+        assertThat(k1.hashCode(), is(k2.hashCode()));
+        assertThat(k1.getDefMd5(), is(defMd5));
+        assertThat(k1.toString(), is(configKey.toString() + "," + defMd5));
+        assertThat(k5.hashCode(), is(not(k1.hashCode())));
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/ConfigDefinitionBuilderTest.java b/config/src/test/java/com/yahoo/vespa/config/ConfigDefinitionBuilderTest.java
new file mode 100644
index 00000000000..cb1cccc0139
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/ConfigDefinitionBuilderTest.java
@@ -0,0 +1,141 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.codegen.CNode;
+import com.yahoo.config.codegen.DefParser;
+import org.junit.Test;
+
+import java.io.File;
+import java.io.FileReader;
+import java.io.IOException;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.*;
+
+
+/**
+ * Unit tests for ConfigDefinitionBuilder.
+ *
+ * @author <a href="musum@yahoo-inc.com">Harald Musum</a>
+ */
+public class ConfigDefinitionBuilderTest {
+
+    private static final String TEST_DIR = "src/test/resources/configs/def-files";
+    private static final String DEF_NAME = TEST_DIR + "/function-test.def";
+
+
+    @Test
+    // TODO Test ranges
+    public void testCreateConfigDefinition() throws IOException, InterruptedException {
+        File defFile = new File(DEF_NAME);
+        DefParser defParser = new DefParser(defFile.getName(), new FileReader(defFile));
+        CNode root = defParser.getTree();
+
+        ConfigDefinition def = ConfigDefinitionBuilder.createConfigDefinition(root);
+
+        assertNotNull(def);
+        assertThat(def.getBoolDefs().size(), is(2));
+        assertNull(def.getBoolDefs().get("bool_val").getDefVal());
+        assertThat(def.getBoolDefs().get("bool_with_def").getDefVal(), is(false));
+
+        assertThat(def.getIntDefs().size(), is(2));
+        assertNull(def.getIntDefs().get("int_val").getDefVal());
+        assertThat(def.getIntDefs().get("int_with_def").getDefVal(), is(-545));
+
+        assertThat(def.getLongDefs().size(), is(2));
+        assertNull(def.getLongDefs().get("long_val").getDefVal());
+        assertThat(def.getLongDefs().get("long_with_def").getDefVal(), is(-50000000000L));
+
+        assertThat(def.getDoubleDefs().size(), is(2));
+        assertNull(def.getDoubleDefs().get("double_val").getDefVal());
+        assertThat(def.getDoubleDefs().get("double_with_def").getDefVal(), is(-6.43));
+
+        assertThat(def.getEnumDefs().size(), is(3));
+        assertTrue(def.getEnumDefs().containsKey("enum_val"));
+        assertThat(def.getEnumDefs().get("enum_val").getVals().size(), is(3));
+        assertThat(def.getEnumDefs().get("enum_val").getVals().get(0), is("FOO"));
+        assertThat(def.getEnumDefs().get("enum_val").getVals().get(1), is("BAR"));
+        assertThat(def.getEnumDefs().get("enum_val").getVals().get(2), is("FOOBAR"));
+
+        assertTrue(def.getEnumDefs().containsKey("enumwithdef"));
+        assertThat(def.getEnumDefs().get("enumwithdef").getDefVal(), is("BAR2"));
+
+        assertTrue(def.getEnumDefs().containsKey("onechoice"));
+        assertThat(def.getEnumDefs().get("onechoice").getDefVal(), is("ONLYFOO"));
+
+        assertThat(def.getStringDefs().size(), is(2));
+        assertNull(def.getStringDefs().get("string_val").getDefVal()); // The return value is a String, so null if no default value
+        assertThat(def.getStringDefs().get("stringwithdef").getDefVal(), is("foobar"));
+
+        assertThat(def.getReferenceDefs().size(), is(2));
+        assertNotNull(def.getReferenceDefs().get("refval"));
+        assertThat(def.getReferenceDefs().get("refwithdef").getDefVal(), is(":parent:"));
+
+        assertThat(def.getFileDefs().size(), is(1));
+        assertNotNull(def.getFileDefs().get("fileVal"));
+
+        assertThat(def.getArrayDefs().size(), is(9));
+        assertNotNull(def.getArrayDefs().get("boolarr"));
+        assertThat(def.getArrayDefs().get("boolarr").getTypeSpec().getType(), is("bool"));
+
+        assertNotNull(def.getArrayDefs().get("enumarr"));
+        assertThat(def.getArrayDefs().get("enumarr").getTypeSpec().getType(), is("enum"));
+        assertThat(def.getArrayDefs().get("enumarr").getTypeSpec().getEnumVals().toString(), is("[ARRAY, VALUES]"));
+
+        assertNotNull(def.getArrayDefs().get("refarr"));
+        assertThat(def.getArrayDefs().get("refarr").getTypeSpec().getType(), is("reference"));
+
+        assertNotNull(def.getArrayDefs().get("fileArr"));
+        assertThat(def.getArrayDefs().get("fileArr").getTypeSpec().getType(), is("file"));
+
+        assertThat(def.getStructDefs().size(), is(2));
+        assertNotNull(def.getStructDefs().get("basicStruct"));
+        assertThat(def.getStructDefs().get("basicStruct").getStringDefs().size(), is(1));
+        assertThat(def.getStructDefs().get("basicStruct").getStringDefs().get("foo").getDefVal(), is("basic"));
+        assertThat(def.getStructDefs().get("basicStruct").getIntDefs().size(), is(1));
+        assertNull(def.getStructDefs().get("basicStruct").getIntDefs().get("bar").getDefVal());
+        assertThat(def.getStructDefs().get("basicStruct").getArrayDefs().size(), is(1));
+        assertThat(def.getStructDefs().get("basicStruct").getArrayDefs().get("intArr").getTypeSpec().getType(), is("int"));
+
+        assertNotNull(def.getStructDefs().get("rootStruct"));
+        assertNotNull(def.getStructDefs().get("rootStruct").getStructDefs().get("inner0"));
+        assertNotNull(def.getStructDefs().get("rootStruct").getStructDefs().get("inner1"));
+        assertThat(def.getStructDefs().get("rootStruct").getInnerArrayDefs().size(), is(1));
+        assertNotNull(def.getStructDefs().get("rootStruct").getInnerArrayDefs().get("innerArr"));
+        assertThat(def.getStructDefs().get("rootStruct").getInnerArrayDefs().get("innerArr").getStringDefs().size(), is(1));
+
+        assertThat(def.getInnerArrayDefs().size(), is(1));
+        assertNotNull(def.getInnerArrayDefs().get("myarray"));
+        assertThat(def.getInnerArrayDefs().get("myarray").getIntDefs().get("intval").getDefVal(), is(14));
+        assertThat(def.getInnerArrayDefs().get("myarray").getArrayDefs().size(), is(1));
+        assertNotNull(def.getInnerArrayDefs().get("myarray").getArrayDefs().get("stringval"));
+        assertThat(def.getInnerArrayDefs().get("myarray").getArrayDefs().get("stringval").getTypeSpec().getType(), is("string"));
+        assertThat(def.getInnerArrayDefs().get("myarray").getEnumDefs().get("enumval").getDefVal(), is("TYPE"));
+        assertNull(def.getInnerArrayDefs().get("myarray").getReferenceDefs().get("refval").getDefVal());
+        assertThat(def.getInnerArrayDefs().get("myarray").getInnerArrayDefs().size(), is(1));
+        assertThat(def.getInnerArrayDefs().get("myarray").getInnerArrayDefs().get("anotherarray").getIntDefs().get("foo").getDefVal(), is(-4));
+        assertNull(def.getInnerArrayDefs().get("myarray").getStructDefs().get("myStruct").getIntDefs().get("a").getDefVal());
+        assertThat(def.getInnerArrayDefs().get("myarray").getStructDefs().get("myStruct").getIntDefs().get("b").getDefVal(), is(2));
+
+        // Maps
+        assertEquals(def.getLeafMapDefs().size(), 4);
+        assertEquals(def.getLeafMapDefs().get("intMap").getTypeSpec().getType(), "int");
+        assertEquals(def.getLeafMapDefs().get("stringMap").getTypeSpec().getType(), "string");
+        assertEquals(def.getStructMapDefs().size(), 1);
+        assertEquals(def.getStructMapDefs().get("myStructMap").getIntDefs().get("myInt").getDefVal(), null);
+        assertEquals(def.getStructMapDefs().get("myStructMap").getStringDefs().get("myString").getDefVal(), null);
+        assertEquals(def.getStructMapDefs().get("myStructMap").getIntDefs().get("myIntDef").getDefVal(), (Integer)56);
+        assertEquals(def.getStructMapDefs().get("myStructMap").getStringDefs().get("myStringDef").getDefVal(), "g");
+
+    }
+
+    @Test
+    public void testCreateConfigDefinitionOverrideNamespace() throws IOException, InterruptedException {
+        File defFile = new File(DEF_NAME);
+        DefParser defParser = new DefParser(defFile.getName(), new FileReader(defFile));
+        CNode root = defParser.getTree();
+
+        ConfigDefinition def = ConfigDefinitionBuilder.createConfigDefinition(root, "foo");
+        assertThat(def.getNamespace(), is("foo"));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/ConfigDefinitionKeyTest.java b/config/src/test/java/com/yahoo/vespa/config/ConfigDefinitionKeyTest.java
new file mode 100644
index 00000000000..fbdca4af6df
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/ConfigDefinitionKeyTest.java
@@ -0,0 +1,42 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import org.junit.Test;
+
+import static junit.framework.TestCase.assertFalse;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+
+/**
+ * Tests ConfigDefinitionKey
+ *
+ * @author musum
+ */
+public class ConfigDefinitionKeyTest {
+
+    @Test
+    public void testBasic() {
+        ConfigDefinitionKey def1 = new ConfigDefinitionKey("foo", "");
+        ConfigDefinitionKey def2 = new ConfigDefinitionKey("foo", "bar");
+
+        assertThat(def1.getName(), is("foo"));
+        assertThat(def1.getNamespace(), is(""));
+
+        assertTrue(def1.equals(def1));
+        assertFalse(def1.equals(def2));
+        assertFalse(def1.equals(new Object()));
+        assertTrue(def2.equals(def2));
+    }
+
+    @Test
+    public void testCreationFromConfigKey() {
+        ConfigKey<?> key1 = new ConfigKey<>("foo", "id", "bar");
+        ConfigDefinitionKey def1 = new ConfigDefinitionKey(key1);
+
+        assertThat(def1.getName(), is(key1.getName()));
+        assertThat(def1.getNamespace(), is(key1.getNamespace()));
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/ConfigDefinitionSetTest.java b/config/src/test/java/com/yahoo/vespa/config/ConfigDefinitionSetTest.java
new file mode 100644
index 00000000000..a00c013109e
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/ConfigDefinitionSetTest.java
@@ -0,0 +1,57 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import org.junit.Test;
+
+import static junit.framework.TestCase.assertNull;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+
+/**
+ * Class to hold config definitions and resolving requests for the correct definition
+ *
+ * @author Harald Musum <musum@yahoo-inc.com>
+ * @since 2011-11-18
+ */
+public class ConfigDefinitionSetTest {
+
+    @Test
+    public void testBasic() {
+        ConfigDefinitionSet configDefinitionSet = new ConfigDefinitionSet();
+        ConfigDefinition def1 = new ConfigDefinition("foo", "1");
+        ConfigDefinition def2 = new ConfigDefinition("foo", "1", "namespace1");
+        ConfigDefinition def3 = new ConfigDefinition("foo", "1", "namespace2");
+        final ConfigDefinitionKey key1 = new ConfigDefinitionKey(def1.getName(), def1.getNamespace());
+        configDefinitionSet.add(key1, def1);
+        ConfigDefinitionKey key2 = new ConfigDefinitionKey(def2.getName(), def2.getNamespace());
+        configDefinitionSet.add(key2, def2);
+        ConfigDefinitionKey key3 = new ConfigDefinitionKey(def3.getName(), def3.getNamespace());
+        configDefinitionSet.add(key3, def3);
+        assertThat(configDefinitionSet.size(), is(3));
+        assertThat(configDefinitionSet.get(key1), is(def1));
+        assertThat(configDefinitionSet.get(key2), is(def2));
+        assertThat(configDefinitionSet.get(key3), is(def3));
+
+        String str = configDefinitionSet.toString();
+        assertTrue(str.contains("namespace1.foo"));
+        assertTrue(str.contains("namespace2.foo"));
+        assertTrue(str.contains("config.foo"));
+    }
+
+    @Test
+    public void testFallbackToDefaultNamespace() {
+        ConfigDefinitionSet configDefinitionSet = new ConfigDefinitionSet();
+        ConfigDefinition def1 = new ConfigDefinition("foo", "1");
+        ConfigDefinition def2 = new ConfigDefinition("bar", "1", "namespace");
+
+        configDefinitionSet.add(new ConfigDefinitionKey(def1.getName(), def1.getNamespace()), def1);
+        configDefinitionSet.add(new ConfigDefinitionKey(def2.getName(), def2.getNamespace()), def2);
+
+        // fallback to default namespace
+        assertThat(configDefinitionSet.get(new ConfigDefinitionKey("foo", "namespace")), is(def1));
+        // Should not fallback to some other config with same name, but different namespace (not default namespace)
+        assertNull(configDefinitionSet.get(new ConfigDefinitionKey("bar", "someothernamespace")));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/ConfigDefinitionTest.java b/config/src/test/java/com/yahoo/vespa/config/ConfigDefinitionTest.java
new file mode 100755
index 00000000000..ce03d5f6823
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/ConfigDefinitionTest.java
@@ -0,0 +1,234 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import org.junit.Test;
+
+import com.yahoo.vespa.config.ConfigDefinition.EnumDef;
+
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.*;
+
+/**
+ * Unit tests for ConfigDefinition.
+ *
+ * @author <a href="musum@yahoo-inc.com">Harald Musum</a>
+ */
+public class ConfigDefinitionTest {
+
+    @Test
+    public void testVersionComparator() {
+        Comparator<String> c = new ConfigDefinition.VersionComparator();
+
+        assertEquals(0, c.compare("1", "1"));
+        assertEquals(0, c.compare("1-0", "1"));
+        assertEquals(0, c.compare("1-0-0", "1"));
+        assertEquals(0, c.compare("1-0-0", "1-0"));
+        assertEquals(0, c.compare("0-1-1", "0-1-1"));
+        assertEquals(0, c.compare("0-1-0", "0-1"));
+        assertEquals(-1, c.compare("0", "1"));
+        assertEquals(-1, c.compare("0-1-0", "0-1-1"));
+        assertEquals(-1, c.compare("0-1-0", "1-1-1"));
+        assertEquals(-1, c.compare("0-0-1", "0-1"));
+        assertEquals(1, c.compare("0-1-1", "0-1-0"));
+        assertEquals(1, c.compare("1-1-1", "0-1-0"));
+        assertEquals(1, c.compare("0-1", "0-0-1"));
+        assertEquals(1, c.compare("1-1", "1"));
+
+        List<String> versions = Arrays.asList("25", "5", "1-1", "0-2-3", "1", "1-0");
+        Collections.sort(versions, new ConfigDefinition.VersionComparator());
+        List<String> solution = Arrays.asList("0-2-3", "1", "1-0", "1-1", "5", "25");
+        assertEquals(solution, versions);
+    }
+
+    @Test
+    public void testDefNumberCompare() {
+        ConfigDefinition df1 = new ConfigDefinition("d", "25");
+        ConfigDefinition df2 = new ConfigDefinition("d", "5");
+        ConfigDefinition df3 = new ConfigDefinition("d", "1-1");
+        ConfigDefinition df4 = new ConfigDefinition("d", "0-2-3");
+        ConfigDefinition df5 = new ConfigDefinition("d", "1");
+        ConfigDefinition df6 = new ConfigDefinition("d", "1-0");
+        assertTrue(df1.compareTo(df2) > 0);
+        assertTrue(df2.compareTo(df4) > 0);
+        assertEquals(1, df3.compareTo(df4));
+        assertEquals(-1, df4.compareTo(df5));
+        assertEquals(0, df5.compareTo(df6));
+    }
+
+    @Test
+    public void testIntDefaultValues() {
+        ConfigDefinition def = new ConfigDefinition("foo", "1");
+
+        def.addIntDef("foo");
+        def.addIntDef("bar", 0);
+        def.addIntDef("baz", 1);
+        def.addIntDef("xyzzy", 2, 0, null);
+
+        assertNull(def.getIntDefs().get("foo").getDefVal());
+        assertThat(def.getIntDefs().get("foo").getMin(), is(ConfigDefinition.INT_MIN));
+        assertThat(def.getIntDefs().get("foo").getMax(), is(ConfigDefinition.INT_MAX));
+        assertThat(def.getIntDefs().get("bar").getDefVal(), is(0));
+        assertThat(def.getIntDefs().get("baz").getDefVal(), is(1));
+
+        assertThat(def.getIntDefs().get("xyzzy").getDefVal(), is(2));
+        assertThat(def.getIntDefs().get("xyzzy").getMin(), is(0));
+        assertThat(def.getIntDefs().get("xyzzy").getMax(), is(ConfigDefinition.INT_MAX));
+    }
+
+    @Test
+    public void testLongDefaultValues() {
+        ConfigDefinition def = new ConfigDefinition("foo", "1");
+
+        def.addLongDef("foo");
+        def.addLongDef("bar", 1234567890123L);
+        def.addLongDef("xyzzy", 2L, 0L, null);
+
+        assertNull(def.getLongDefs().get("foo").getDefVal());
+        assertThat(def.getLongDefs().get("foo").getMin(), is(ConfigDefinition.LONG_MIN));
+        assertThat(def.getLongDefs().get("foo").getMax(), is(ConfigDefinition.LONG_MAX));
+        assertThat(def.getLongDefs().get("bar").getDefVal(), is(1234567890123L));
+
+        assertThat(def.getLongDefs().get("xyzzy").getDefVal(), is(2L));
+        assertThat(def.getLongDefs().get("xyzzy").getMin(), is(0L));
+        assertThat(def.getLongDefs().get("xyzzy").getMax(), is(ConfigDefinition.LONG_MAX));
+    }
+
+    @Test
+    @SuppressWarnings("serial")
+    public void testDefaultsPayloadMap() {
+        ConfigDefinition def = new ConfigDefinition("foo", "1");
+        def.addStringDef("mystring");
+        def.addStringDef("mystringdef", "foo");
+        def.addBoolDef("mybool");
+        def.addBoolDef("mybooldef", true);
+        def.addIntDef("myint");
+        def.addIntDef("myintdef", 1);
+        def.addLongDef("mylong");
+        def.addLongDef("mylongdef", 11l);
+        def.addDoubleDef("mydouble");
+        def.addDoubleDef("mydoubledef", 2d);
+        EnumDef ed = new EnumDef(new ArrayList<String>(){{add("a1"); add("a2");}}, null);
+        EnumDef eddef = new EnumDef(new ArrayList<String>(){{add("a11"); add("a22");}}, "a22");
+        def.addEnumDef("myenum", ed);
+        def.addEnumDef("myenumdef", eddef);
+        def.addReferenceDef("myref");
+        def.addReferenceDef("myrefdef", "reff");
+        def.addFileDef("myfile");
+        def.addFileDef("myfiledef", "etc");
+    }
+
+    @Test
+    public void testVerification() {
+        ConfigDefinition def = new ConfigDefinition("foo", "1", "bar");
+        def.addBoolDef("boolval");
+        def.addStringDef("stringval");
+        def.addIntDef("intval");
+        def.addLongDef("longval");
+        def.addDoubleDef("doubleval");
+        def.addEnumDef("enumval", new EnumDef(Arrays.asList("FOO"), "FOO"));
+        def.addReferenceDef("refval");
+        def.addFileDef("fileval");
+        def.addInnerArrayDef("innerarr");
+        def.addLeafMapDef("leafmap");
+        ConfigDefinition.ArrayDef intArray = def.arrayDef("intArray");
+        intArray.setTypeSpec(new ConfigDefinition.TypeSpec("intArray", "int", null, null, Integer.MIN_VALUE, Integer.MAX_VALUE));
+
+        ConfigDefinition.ArrayDef longArray = def.arrayDef("longArray");
+        longArray.setTypeSpec(new ConfigDefinition.TypeSpec("longArray", "long", null, null, Long.MIN_VALUE, Long.MAX_VALUE));
+
+        ConfigDefinition.ArrayDef doubleArray = def.arrayDef("doubleArray");
+        doubleArray.setTypeSpec(new ConfigDefinition.TypeSpec("doubleArray", "double", null, null, Double.MIN_VALUE, Double.MAX_VALUE));
+
+        ConfigDefinition.ArrayDef enumArray = def.arrayDef("enumArray");
+        enumArray.setTypeSpec(new ConfigDefinition.TypeSpec("enumArray", "enum", null, "VALID", null, null));
+
+        ConfigDefinition.ArrayDef stringArray = def.arrayDef("stringArray");
+        stringArray.setTypeSpec(new ConfigDefinition.TypeSpec("stringArray", "string", null, null, null, null));
+
+        def.structDef("struct");
+
+        assertVerify(def, "boolval", "true", 0);
+        assertVerify(def, "boolval", "false", 0);
+        assertVerify(def, "boolval", "invalid", IllegalArgumentException.class);
+
+
+        assertVerify(def, "stringval", "foobar", 0);
+        assertVerify(def, "stringval", "foobar", 0);
+        assertVerify(def, "intval", "123", 0);
+        assertVerify(def, "intval", "foobar", IllegalArgumentException.class);
+        assertVerify(def, "longval", "1234", 0);
+        assertVerify(def, "longval", "foobar", IllegalArgumentException.class);
+        assertVerify(def, "doubleval", "foobar", IllegalArgumentException.class);
+        assertVerify(def, "doubleval", "3", 0);
+        assertVerify(def, "doubleval", "3.14", 0);
+        assertVerify(def, "enumval", "foobar", IllegalArgumentException.class);
+        assertVerify(def, "enumval", "foo", IllegalArgumentException.class);
+        assertVerify(def, "enumval", "FOO", 0);
+        assertVerify(def, "refval", "foobar", 0);
+        assertVerify(def, "fileval", "foobar", 0);
+
+        assertVerifyComplex(def, "innerarr", 0);
+        assertVerifyComplex(def, "leafmap", 0);
+        assertVerifyComplex(def, "intArray", 0);
+        assertVerifyComplex(def, "longArray", 0);
+        assertVerifyComplex(def, "doubleArray", 0);
+        assertVerifyComplex(def, "enumArray", 0);
+        assertVerifyComplex(def, "stringArray", 0);
+        assertVerifyArray(intArray, "1345", 0, 0);
+        assertVerifyArray(intArray, "invalid", 0, IllegalArgumentException.class);
+        assertVerifyArray(longArray, "1345", 0, 0);
+        assertVerifyArray(longArray, "invalid", 0, IllegalArgumentException.class);
+        assertVerifyArray(doubleArray, "1345", 0, 0);
+        assertVerifyArray(doubleArray, "1345.3", 0, 0);
+        assertVerifyArray(doubleArray, "invalid", 0, IllegalArgumentException.class);
+        assertVerifyArray(enumArray, "valid", 0, IllegalArgumentException.class);
+        assertVerifyArray(enumArray, "VALID", 0, 0);
+        assertVerifyArray(enumArray, "inVALID", 0, IllegalArgumentException.class);
+        assertVerifyArray(stringArray, "VALID", 0, 0);
+        assertVerifyComplex(def, "struct", 0);
+    }
+
+    private void assertVerifyArray(ConfigDefinition.ArrayDef def, String val, int index, int expectedNumWarnings) {
+        List<String> issuedWarnings = new ArrayList<>();
+        def.verify(val, index, issuedWarnings);
+        assertThat(issuedWarnings.size(), is(expectedNumWarnings));
+    }
+
+    private void assertVerifyArray(ConfigDefinition.ArrayDef def, String val, int index, Class<?> expectedException) {
+        try {
+            def.verify(val, index, new ArrayList<String>());
+        } catch (Exception e) {
+            if (!(e.getClass().isAssignableFrom(expectedException))) {
+                throw e;
+            }
+        }
+    }
+
+    private void assertVerify(ConfigDefinition def, String id, String val, int expectedNumWarnings) {
+        List<String> issuedWarnings = new ArrayList<>();
+        def.verify(id, val, issuedWarnings);
+        assertThat(issuedWarnings.size(), is(expectedNumWarnings));
+    }
+
+    private void assertVerify(ConfigDefinition def, String id, String val, Class<?> expectedException) {
+        try {
+            def.verify(id, val, new ArrayList<String>());
+        } catch (Exception e) {
+            if (!(e.getClass().isAssignableFrom(expectedException))) {
+                throw e;
+            }
+        }
+    }
+
+    private void assertVerifyComplex(ConfigDefinition def, String id, int expectedNumWarnings) {
+        List<String> issuedWarnings = new ArrayList<>();
+        def.verify(id, issuedWarnings);
+        assertThat(issuedWarnings.size(), is(expectedNumWarnings));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/ConfigFileFormatterTest.java b/config/src/test/java/com/yahoo/vespa/config/ConfigFileFormatterTest.java
new file mode 100644
index 00000000000..0e55714ca53
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/ConfigFileFormatterTest.java
@@ -0,0 +1,336 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.foo.ArraytypesConfig;
+import com.yahoo.foo.SimpletypesConfig;
+import com.yahoo.foo.StructtypesConfig;
+import com.yahoo.config.codegen.DefParser;
+import com.yahoo.config.codegen.InnerCNode;
+import com.yahoo.foo.MaptypesConfig;
+import com.yahoo.slime.Cursor;
+import com.yahoo.slime.Slime;
+import com.yahoo.text.StringUtilities;
+import com.yahoo.text.Utf8;
+import org.junit.Test;
+import org.junit.Ignore;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.StringReader;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author lulf
+ * @since 5.1
+ */
+public class ConfigFileFormatterTest {
+
+    private String expected_simpletypes = "stringval \"foo\"\n" +
+            "intval 324234\n"  +
+            "longval 324\n"  +
+            "doubleval 3.455\n" +
+            "enumval VAL2\n" +
+            "boolval true\n";
+
+    @Test
+    public void require_that_basic_formatting_is_correct() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("stringval", "foo");
+        root.setString("intval", "324234");
+        root.setString("longval", "324");
+        root.setString("doubleval", "3.455");
+        root.setString("enumval", "VAL2");
+        root.setString("boolval", "true");
+
+        assertConfigFormat(slime, expected_simpletypes);
+    }
+
+    @Test
+    public void require_that_basic_formatting_is_correct_with_types() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("stringval", "foo");
+        root.setLong("intval", 324234);
+        root.setLong("longval", 324);
+        root.setDouble("doubleval", 3.455);
+        root.setString("enumval", "VAL2");
+        root.setBool("boolval", true);
+
+        assertConfigFormat(slime, expected_simpletypes);
+    }
+
+    private void assertConfigFormat(Slime slime, String expected_simpletypes) throws IOException {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        new ConfigFileFormat(def).encode(baos, slime);
+        assertThat(baos.toString(), is(expected_simpletypes));
+    }
+
+    @Test
+    public void require_that_field_not_found_is_ignored() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("nosuchfield", "bar");
+        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        new ConfigFileFormat(def).encode(baos, slime);
+        assertThat(baos.toString(), is(""));
+    }
+
+    // TODO: Reenable this when we can reenable typechecking.
+    @Ignore
+    @Test(expected = IllegalArgumentException.class)
+    public void require_that_illegal_int_throws_exception() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("intval", "invalid");
+        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        new ConfigFileFormat(def).encode(new ByteArrayOutputStream(), slime);
+    }
+
+    // TODO: Reenable this when we can reenable typechecking.
+    @Ignore
+    @Test(expected = IllegalArgumentException.class)
+    public void require_that_illegal_long_throws_exception() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("longval", "invalid");
+        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        new ConfigFileFormat(def).encode(new ByteArrayOutputStream(), slime);
+    }
+
+    // TODO: Reenable this when we can reenable typechecking.
+    @Ignore
+    @Test(expected = IllegalArgumentException.class)
+    public void require_that_illegal_double_throws_exception() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("doubleval", "invalid");
+        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        new ConfigFileFormat(def).encode(new ByteArrayOutputStream(), slime);
+    }
+
+    @Test
+    public void require_that_illegal_boolean_becomes_false() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("boolval", "invalid");
+        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        new ConfigFileFormat(def).encode(baos, slime);
+        assertThat(baos.toString(), is("boolval false\n"));
+    }
+
+    // TODO: Remove this when we can reenable typechecking.
+    @Test
+    public void require_that_types_are_not_checked() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("enumval", "null");
+        root.setString("intval", "null");
+        root.setString("longval", "null");
+        root.setString("boolval", "null");
+        root.setString("doubleval", "null");
+        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        new ConfigFileFormat(def).encode(baos, slime);
+        assertThat(baos.toString("UTF-8"), is("enumval null\nintval null\nlongval null\nboolval false\ndoubleval null\n"));
+    }
+
+    // TODO: Reenable this when we can reenable typechecking.
+    @Ignore
+    @Test(expected = IllegalArgumentException.class)
+    public void require_that_illegal_enum_throws_exception() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("enumval", "invalid");
+        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        new ConfigFileFormat(def).encode(new ByteArrayOutputStream(), slime);
+    }
+
+    @Test
+    public void require_that_strings_are_encoded() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        String value = "\u7d22";
+        root.setString("stringval", value);
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        new ConfigFileFormat(def).encode(baos, slime);
+        assertThat(baos.toString("UTF-8"), is("stringval \"" + value + "\"\n"));
+    }
+
+    @Test
+    public void require_that_array_formatting_is_correct() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        Cursor boolarr = root.setArray("boolarr");
+        boolarr.addString("true");
+        boolarr.addString("false");
+        Cursor doublearr = root.setArray("doublearr");
+        doublearr.addString("3.14");
+        doublearr.addString("1.414");
+        Cursor enumarr = root.setArray("enumarr");
+        enumarr.addString("VAL1");
+        enumarr.addString("VAL2");
+        Cursor intarr = root.setArray("intarr");
+        intarr.addString("3");
+        intarr.addString("5");
+        Cursor longarr = root.setArray("longarr");
+        longarr.addString("55");
+        longarr.addString("66");
+        Cursor stringarr = root.setArray("stringarr");
+        stringarr.addString("foo");
+        stringarr.addString("bar");
+
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        InnerCNode def = new DefParser("arraytypes", new StringReader(StringUtilities.implode(ArraytypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        new ConfigFileFormat(def).encode(baos, slime);
+        assertThat(baos.toString(), is(
+                "boolarr[0] true\n" +
+                "boolarr[1] false\n" +
+                "doublearr[0] 3.14\n" +
+                "doublearr[1] 1.414\n" +
+                "enumarr[0] VAL1\n" +
+                "enumarr[1] VAL2\n" +
+                "intarr[0] 3\n" +
+                "intarr[1] 5\n" +
+                "longarr[0] 55\n" +
+                "longarr[1] 66\n" +
+                "stringarr[0] \"foo\"\n" +
+                "stringarr[1] \"bar\"\n"));
+    }
+
+    @Test
+    public void require_that_map_formatting_is_correct() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        Cursor boolval = root.setObject("boolmap");
+        boolval.setString("foo", "true");
+        boolval.setString("bar", "false");
+        root.setObject("intmap").setString("foo", "1234");
+        root.setObject("longmap").setString("foo", "12345");
+        root.setObject("doublemap").setString("foo", "3.14");
+        root.setObject("stringmap").setString("foo", "bar");
+        root.setObject("innermap").setObject("bar").setString("foo", "1234");
+        root.setObject("nestedmap").setObject("baz").setObject("inner").setString("foo", "1234");
+
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        InnerCNode def = new DefParser("maptypes", new StringReader(StringUtilities.implode(MaptypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        new ConfigFileFormat(def).encode(baos, slime);
+        assertThat(baos.toString(), is(
+                "boolmap{\"foo\"} true\n" +
+                "boolmap{\"bar\"} false\n" +
+                "intmap{\"foo\"} 1234\n" +
+                "longmap{\"foo\"} 12345\n" +
+                "doublemap{\"foo\"} 3.14\n" +
+                "stringmap{\"foo\"} \"bar\"\n" +
+                "innermap{\"bar\"}.foo 1234\n" +
+                "nestedmap{\"baz\"}.inner{\"foo\"} 1234\n"));
+    }
+
+    @Test
+    public void require_that_struct_formatting_is_correct() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        Cursor simple = root.setObject("simple");
+        simple.setString("name", "myname");
+        simple.setString("gender", "FEMALE");
+        Cursor array = simple.setArray("emails");
+        array.addString("foo@bar.com");
+        array.addString("bar@baz.net");
+
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        InnerCNode def = new DefParser("structtypes", new StringReader(StringUtilities.implode(StructtypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        new ConfigFileFormat(def).encode(baos, slime);
+        assertThat(baos.toString(), is(
+                "simple.name \"myname\"\n" +
+                "simple.gender FEMALE\n" +
+                "simple.emails[0] \"foo@bar.com\"\n" +
+                "simple.emails[1] \"bar@baz.net\"\n"
+        ));
+    }
+
+    @Test
+    public void require_that_complex_struct_formatting_is_correct() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+
+        Cursor nested = root.setObject("nested");
+        Cursor nested_inner = nested.setObject("inner");
+        nested_inner.setString("name", "baz");
+        nested_inner.setString("gender", "FEMALE");
+        Cursor nested_inner_arr = nested_inner.setArray("emails");
+        nested_inner_arr.addString("foo");
+        nested_inner_arr.addString("bar");
+
+        Cursor nestedarr = root.setArray("nestedarr");
+        Cursor nestedarr1 = nestedarr.addObject();
+        Cursor inner1 = nestedarr1.setObject("inner");
+        inner1.setString("name", "foo");
+        inner1.setString("gender", "FEMALE");
+        Cursor inner1arr = inner1.setArray("emails");
+        inner1arr.addString("foo@bar");
+        inner1arr.addString("bar@foo");
+
+        Cursor complexarr = root.setArray("complexarr");
+        Cursor complexarr1 = complexarr.addObject();
+        Cursor innerarr1 = complexarr1.setArray("innerarr");
+        Cursor innerarr11 = innerarr1.addObject();
+        innerarr11.setString("name", "bar");
+        innerarr11.setString("gender", "MALE");
+
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        InnerCNode def = new DefParser("structtypes", new StringReader(StringUtilities.implode(StructtypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        new ConfigFileFormat(def).encode(baos, slime);
+        assertThat(baos.toString(), is(
+                        "nested.inner.name \"baz\"\n" +
+                        "nested.inner.gender FEMALE\n" +
+                        "nested.inner.emails[0] \"foo\"\n" +
+                        "nested.inner.emails[1] \"bar\"\n" +
+                        "nestedarr[0].inner.name \"foo\"\n" +
+                        "nestedarr[0].inner.gender FEMALE\n" +
+                        "nestedarr[0].inner.emails[0] \"foo@bar\"\n" +
+                        "nestedarr[0].inner.emails[1] \"bar@foo\"\n" +
+                        "complexarr[0].innerarr[0].name \"bar\"\n" +
+                        "complexarr[0].innerarr[0].gender MALE\n"
+        ));
+    }
+
+    @Test
+    public void require_that_strings_are_properly_escaped() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("stringval", "some\"quotes\\\"instring");
+        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        new ConfigFileFormat(def).encode(baos, slime);
+        assertThat(baos.toString(), is("stringval \"some\\\"quotes\\\\\\\"instring\"\n"));
+    }
+
+    @Test
+    @Ignore
+    public void require_that_utf8_works() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        final String input = "Hei \u00E6\u00F8\u00E5 \n \uBC14\uB451 \u00C6\u00D8\u00C5 hallo";
+        root.setString("stringval", input);
+        System.out.println(bytesToHexString(Utf8.toBytes(input)));
+        InnerCNode def = new DefParser("simpletypes", new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n"))).getTree();
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        new ConfigFileFormat(def).encode(baos, slime);
+        System.out.println(bytesToHexString(baos.toByteArray()));
+        assertThat(Utf8.toString(baos.toByteArray()), is("stringval \"" + input + "\"\n"));
+    }
+
+    public static String bytesToHexString(byte[] bytes){
+        StringBuilder sb = new StringBuilder();
+        for(byte b : bytes){
+            sb.append(String.format("%02x", b&0xff));
+        }
+        return sb.toString();
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/ConfigHelperTest.java b/config/src/test/java/com/yahoo/vespa/config/ConfigHelperTest.java
new file mode 100644
index 00000000000..ce625727491
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/ConfigHelperTest.java
@@ -0,0 +1,31 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.subscription.ConfigSourceSet;
+import org.junit.Test;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author <a href="mailto:musum@yahoo-inc.com">Harald Musum</a>
+ * @since 5.1.9
+ */
+public class ConfigHelperTest {
+
+    @Test
+    public void basic() {
+        ConfigSourceSet configSourceSet = new ConfigSourceSet("host.com");
+        ConfigHelper helper = new ConfigHelper(configSourceSet);
+        assertThat(helper.getConfigSourceSet(), is(configSourceSet));
+        assertThat(helper.getConnectionPool().getAllSourceAddresses(), is("host.com"));
+        assertThat(helper.getTimingValues().getSubscribeTimeout(), is(new TimingValues().getSubscribeTimeout()));
+
+        // Specify timing values
+        TimingValues tv = new TimingValues();
+        tv.setSubscribeTimeout(11L);
+        helper = new ConfigHelper(configSourceSet, tv);
+        assertThat(helper.getTimingValues().getSubscribeTimeout(), is(tv.getSubscribeTimeout()));
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/ConfigKeyTest.java b/config/src/test/java/com/yahoo/vespa/config/ConfigKeyTest.java
new file mode 100644
index 00000000000..e824571d9d1
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/ConfigKeyTest.java
@@ -0,0 +1,121 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import java.util.ArrayList;
+import java.util.Collections;
+import java.util.List;
+
+import com.yahoo.foo.AppConfig;
+import com.yahoo.config.ConfigurationRuntimeException;
+import com.yahoo.config.codegen.CNode;
+import org.junit.Test;
+
+import static org.junit.Assert.*;
+
+/**
+ *
+ * @author <a href="musum@yahoo-inc.com">Harald Musum</a>
+ */
+public class ConfigKeyTest {
+
+    @Test
+    public void testConfigId()  {
+        String namespace = "bar";
+        ConfigKey<?> key1 = new ConfigKey<>("foo", "a/b/c", namespace);
+        ConfigKey<?> key2 = new ConfigKey<>("foo", "a/b/c", namespace);
+
+        assertEquals(key1, key2);
+
+        ConfigKey<?> key3 = new ConfigKey<>("foo", "a/b/c/d", namespace);
+        assertTrue(!key1.equals(key3));
+        assertFalse(key1.equals(key3));
+
+        assertEquals("a/b/c", new ConfigKey<>("foo", "a/b/c", namespace).getConfigId());
+        assertEquals("a", new ConfigKey<>("foo", "a", namespace).getConfigId());
+        assertEquals("", new ConfigKey<>("foo", "", namespace).getConfigId());
+
+        assertTrue(key1.equals(key1));
+        assertFalse(key1.equals(key3));
+        assertFalse(key1.equals(new Object()));
+
+        ConfigKey<?> key4 = new ConfigKey<>("myConfig", null, namespace);
+        assertEquals("", key4.getConfigId());
+    }
+
+    @Test
+    public void testConfigKey() {
+        String name = AppConfig.CONFIG_DEF_NAME;
+        String namespace = AppConfig.CONFIG_DEF_NAMESPACE;
+        String md5 = AppConfig.CONFIG_DEF_MD5;
+        String configId = "myId";
+
+        ConfigKey<AppConfig> classKey = new ConfigKey<>(AppConfig.class, configId);
+        assertEquals("Name is set correctly from class", name, classKey.getName());
+        assertEquals("Namespace is set correctly from class", namespace, classKey.getNamespace());
+        assertEquals(configId, classKey.getConfigId());
+        assertEquals("Md5 is set correctly from class", md5, classKey.getMd5());
+
+        ConfigKey<?> stringKey = new ConfigKey<>(name, configId, namespace);
+        assertEquals("Key created from class equals key created from strings", stringKey, classKey);
+    }
+
+    @Test(expected = ConfigurationRuntimeException.class)
+    public void testNoName() {
+        new ConfigKey<>(null, "", "");
+    }
+
+    // Tests namespace and equals with combinations of namespace.
+    @Test
+    public void testNamespace() {
+        ConfigKey<?> noNamespace = new ConfigKey<>("name", "id", null);
+        ConfigKey<?> namespaceFoo = new ConfigKey<>("name", "id", "foo");
+        ConfigKey<?> namespaceBar = new ConfigKey<>("name", "id", "bar");
+        assertTrue(noNamespace.equals(noNamespace));
+        assertTrue(namespaceFoo.equals(namespaceFoo));
+        assertFalse(noNamespace.equals(namespaceFoo));
+        assertFalse(namespaceFoo.equals(noNamespace));
+        assertFalse(namespaceFoo.equals(namespaceBar));
+        assertEquals(noNamespace.getNamespace(), CNode.DEFAULT_NAMESPACE);
+        assertEquals(namespaceBar.getNamespace(), "bar");
+    }
+
+    @Test
+    public void testSorting() {
+        ConfigKey<?> k1 = new ConfigKey<>("name3", "id2", "nsc");
+        ConfigKey<?> k2 = new ConfigKey<>("name2", "id2", "nsb");
+        ConfigKey<?> k3 = new ConfigKey<>("name1", "id2", "nsa");
+        List<ConfigKey<?>> keys = new ArrayList<>();
+        keys.add(k2);
+        keys.add(k1);
+        keys.add(k3);
+        Collections.sort(keys);
+        assertEquals(keys.get(0), k3);
+        assertEquals(keys.get(1), k2);
+        assertEquals(keys.get(2), k1);
+
+        k1 = new ConfigKey<>("name2", "id2", "nsa");
+        k2 = new ConfigKey<>("name3", "id3", "nsa");
+        k3 = new ConfigKey<>("name1", "id4", "nsa");
+        keys = new ArrayList<>();
+        keys.add(k3);
+        keys.add(k2);
+        keys.add(k1);
+        Collections.sort(keys);
+        assertEquals(keys.get(0), k3);
+        assertEquals(keys.get(1), k1);
+        assertEquals(keys.get(2), k2);
+
+        k1 = new ConfigKey<>("name", "idC", "nsa");
+        k2 = new ConfigKey<>("name", "idA", "nsa");
+        k3 = new ConfigKey<>("name", "idB", "nsa");
+        keys = new ArrayList<>();
+        keys.add(k1);
+        keys.add(k2);
+        keys.add(k3);
+        Collections.sort(keys);
+        assertEquals(keys.get(0), k2);
+        assertEquals(keys.get(1), k3);
+        assertEquals(keys.get(2), k1);
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/ConfigPayloadBuilderTest.java b/config/src/test/java/com/yahoo/vespa/config/ConfigPayloadBuilderTest.java
new file mode 100644
index 00000000000..24ade0f83c2
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/ConfigPayloadBuilderTest.java
@@ -0,0 +1,363 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.slime.Cursor;
+import com.yahoo.slime.JsonFormat;
+import com.yahoo.slime.Slime;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.util.ArrayList;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author lulf
+ * @since 5.1
+ */
+public class ConfigPayloadBuilderTest {
+
+    private ConfigPayloadBuilder builderWithDef;
+
+    private Cursor createSlime(ConfigPayloadBuilder builder) {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        builder.resolve(root);
+        return root;
+    }
+
+    @Before
+    public void setupBuilder() {
+        ConfigDefinition def = new ConfigDefinition("foo", "1", "bar");
+        def.addBoolDef("boolval");
+        ConfigDefinition mystruct = def.structDef("mystruct");
+        mystruct.addIntDef("foofield");
+        def.arrayDef("myarray").setTypeSpec(new ConfigDefinition.TypeSpec("myarray", "int", null, null, null, null));
+        ConfigDefinition myinnerarray = def.innerArrayDef("myinnerarray");
+        myinnerarray.addIntDef("foo");
+        builderWithDef = new ConfigPayloadBuilder(def, new ArrayList<String>());
+    }
+
+    @Test
+    public void require_that_simple_fields_are_set() {
+        ConfigPayloadBuilder builder = new ConfigPayloadBuilder();
+        builder.setField("foo", "bar");
+        builder.setField("bar", "barz");
+        builder.getObject("bar").setValue("baz");
+        Cursor root = createSlime(builder);
+        assertEquals("bar", root.field("foo").asString());
+        assertEquals("baz", root.field("bar").asString());
+    }
+
+    @Test
+    public void require_that_simple_fields_can_be_overwritten() {
+        ConfigPayloadBuilder builder = new ConfigPayloadBuilder();
+        builder.setField("foo", "bar");
+        builder.setField("foo", "baz");
+        Cursor root = createSlime(builder);
+        // XXX: Not sure if this is the _right_ behavior.
+        assertEquals("baz", root.field("foo").asString());
+    }
+
+    @Test
+    public void require_that_struct_values_are_created() {
+        ConfigPayloadBuilder builder = new ConfigPayloadBuilder();
+        ConfigPayloadBuilder struct = builder.getObject("foo");
+        struct.setField("bar", "baz");
+
+        Cursor root = createSlime(builder);
+        Cursor s = root.field("foo");
+        assertEquals("baz", s.field("bar").asString());
+    }
+
+
+    @Test
+    public void require_that_maps_are_created() {
+        ConfigPayloadBuilder builder = new ConfigPayloadBuilder();
+        ConfigPayloadBuilder.MapBuilder map = builder.getMap("foo");
+        assertNotNull(map);
+    }
+
+    @Test
+    public void require_that_maps_support_simple_values() {
+        ConfigPayloadBuilder builder = new ConfigPayloadBuilder();
+        ConfigPayloadBuilder.MapBuilder map = builder.getMap("foo");
+        map.put("fookey", "foovalue");
+        map.put("barkey", "barvalue");
+        map.put("bazkey", "bazvalue");
+        map.put("fookey", "lolvalue");
+        assertThat(map.getElements().size(), is(3));
+        Cursor root = createSlime(builder);
+        Cursor a = root.field("foo");
+        assertThat(a.field("barkey").asString(), is("barvalue"));
+        assertThat(a.field("bazkey").asString(), is("bazvalue"));
+        assertThat(a.field("fookey").asString(), is("lolvalue"));
+    }
+
+    @Test
+    public void require_that_arrays_are_created() {
+        ConfigPayloadBuilder builder = new ConfigPayloadBuilder();
+        ConfigPayloadBuilder.Array array = builder.getArray("foo");
+        assertNotNull(array);
+    }
+
+    @Test
+    public void require_that_arrays_can_be_appended_simple_values() {
+        ConfigPayloadBuilder builder = new ConfigPayloadBuilder();
+        ConfigPayloadBuilder.Array array = builder.getArray("foo");
+        array.append("bar");
+        array.append("baz");
+        array.append("bim");
+        assertThat(array.getElements().size(), is(3));
+        Cursor root = createSlime(builder);
+        Cursor a = root.field("foo");
+        assertEquals("bar", a.entry(0).asString());
+        assertEquals("baz", a.entry(1).asString());
+        assertEquals("bim", a.entry(2).asString());
+    }
+
+    @Test
+    public void require_that_arrays_can_be_indexed_simple_values() {
+        ConfigPayloadBuilder builder = new ConfigPayloadBuilder();
+        ConfigPayloadBuilder.Array array = builder.getArray("foo");
+        array.set(3, "bar");
+        array.set(2, "baz");
+        array.set(6, "bim");
+        array.set(4, "bum");
+
+        Cursor root = createSlime(builder);
+        Cursor a = root.field("foo");
+        assertEquals("bar", a.entry(0).asString());
+        assertEquals("baz", a.entry(1).asString());
+        assertEquals("bim", a.entry(2).asString());
+        assertEquals("bum", a.entry(3).asString());
+    }
+
+    @Test
+    public void require_that_arrays_can_be_appended_structs() {
+        ConfigPayloadBuilder builder = new ConfigPayloadBuilder();
+        ConfigPayloadBuilder.Array array = builder.getArray("foo");
+        ConfigPayloadBuilder elem1 = array.append();
+        elem1.setField("bar", "baz");
+        ConfigPayloadBuilder elem2 = array.append();
+        elem2.setField("foo", "bar");
+        Cursor root = createSlime(builder);
+        Cursor a = root.field("foo");
+        assertEquals("baz", a.entry(0).field("bar").asString());
+        assertEquals("bar", a.entry(1).field("foo").asString());
+    }
+
+    @Test
+    public void require_that_arrays_can_be_indexed_structs() {
+        ConfigPayloadBuilder builder = new ConfigPayloadBuilder();
+        ConfigPayloadBuilder.Array array = builder.getArray("foo");
+        ConfigPayloadBuilder elem1 = array.set(4);
+        elem1.setField("bar", "baz");
+        ConfigPayloadBuilder elem2 = array.set(2);
+        elem2.setField("foo", "bar");
+
+        Cursor root = createSlime(builder);
+        Cursor a = root.field("foo");
+        assertEquals("baz", a.entry(0).field("bar").asString());
+        assertEquals("bar", a.entry(1).field("foo").asString());
+    }
+
+    @Test
+    public void require_that_get_can_be_used_instead() {
+        ConfigPayloadBuilder builder = new ConfigPayloadBuilder();
+        ConfigPayloadBuilder.Array array = builder.getArray("foo");
+        // Causes append to be used
+        ConfigPayloadBuilder b1 = array.get(0);
+        ConfigPayloadBuilder b2 = array.get(1);
+        ConfigPayloadBuilder b3 = array.get(0);
+        ConfigPayloadBuilder b4 = array.get(1);
+        assertThat(b1, is(b3));
+        assertThat(b2, is(b4));
+
+        ConfigPayloadBuilder.Array array_indexed = builder.getArray("bar");
+        ConfigPayloadBuilder bi3 = array_indexed.set(3);
+        ConfigPayloadBuilder bi1 = array_indexed.set(1);
+        ConfigPayloadBuilder bi32 = array_indexed.get(3);
+        ConfigPayloadBuilder bi12 = array_indexed.get(1);
+        assertThat(bi12, is(bi1));
+        assertThat(bi32, is(bi3));
+    }
+
+    @Test
+    public void require_that_builders_can_be_merged() {
+        ConfigPayloadBuilder b1 = new ConfigPayloadBuilder();
+        ConfigPayloadBuilder b2 = new ConfigPayloadBuilder();
+        ConfigPayloadBuilder b3 = new ConfigPayloadBuilder();
+        b1.setField("aaa", "a");
+        b1.getObject("bbb").setField("ccc", "ddd");
+
+        b2.setField("aaa", "b");
+        b2.getObject("bbb").setField("ccc", "eee");
+        b2.getArray("eee").append("kkk");
+        b2.setField("uuu", "ttt");
+
+        b3.setField("aaa", "c");
+        b3.getObject("bbb").setField("ccc", "fff");
+        b3.getArray("eee").append("lll");
+        b3.setField("uuu", "vvv");
+
+        assertThat(b1.override(b2), is(b1));
+        assertThat(b1.override(b3), is(b1));
+
+        Cursor b1root = createSlime(b1);
+        Cursor b2root = createSlime(b2);
+        Cursor b3root = createSlime(b3);
+        assertThat(b3root.field("aaa").asString(), is("c"));
+        assertThat(b3root.field("bbb").field("ccc").asString(), is("fff"));
+        assertThat(b3root.field("eee").children(), is(1));
+        assertThat(b3root.field("eee").entry(0).asString(), is("lll"));
+        assertThat(b3root.field("uuu").asString(), is("vvv"));
+
+        assertThat(b2root.field("aaa").asString(), is("b"));
+        assertThat(b2root.field("bbb").field("ccc").asString(), is("eee"));
+        assertThat(b2root.field("eee").children(), is(1));
+        assertThat(b2root.field("eee").entry(0).asString(), is("kkk"));
+        assertThat(b2root.field("uuu").asString(), is("ttt"));
+
+        assertThat(b1root.field("aaa").asString(), is("c"));
+        assertThat(b1root.field("bbb").field("ccc").asString(), is("fff"));
+        assertThat(b1root.field("eee").children(), is(2));
+        assertThat(b1root.field("eee").entry(0).asString(), is("kkk"));
+        assertThat(b1root.field("eee").entry(1).asString(), is("lll"));
+        assertThat(b1root.field("uuu").asString(), is("vvv"));
+    }
+
+    @Test(expected=IllegalStateException.class)
+    public void require_that_append_conflicts_with_index() {
+        ConfigPayloadBuilder builder = new ConfigPayloadBuilder();
+        ConfigPayloadBuilder.Array array = builder.getArray("foo");
+        array.set(0, "bar");
+        array.append("baz");
+    }
+
+    @Test(expected=IllegalStateException.class)
+    public void require_that_index_conflicts_with_append() {
+        ConfigPayloadBuilder builder = new ConfigPayloadBuilder();
+        ConfigPayloadBuilder.Array array = builder.getArray("foo");
+        array.append("baz");
+        array.set(0, "bar");
+    }
+
+    @Test
+    public void require_that_builder_can_be_created_from_payload() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("foo", "bar");
+        Cursor obj = root.setObject("foorio");
+        obj.setString("bar", "bam");
+        Cursor obj2 = obj.setObject("bario");
+        obj2.setString("bim", "bul");
+        Cursor a2 = obj.setArray("blim");
+        Cursor arrayobj = a2.addObject();
+        arrayobj.setString("fim", "fam");
+        Cursor arrayobj2 = a2.addObject();
+        arrayobj2.setString("blim", "blam");
+        Cursor a1 = root.setArray("arrio");
+        a1.addString("himbio");
+
+        ConfigPayloadBuilder builder = new ConfigPayloadBuilder(new ConfigPayload(slime));
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        ConfigPayload.fromBuilder(builder).serialize(baos, new JsonFormat(true));
+        assertThat(baos.toString(), is("{\"foo\":\"bar\",\"foorio\":{\"bar\":\"bam\",\"bario\":{\"bim\":\"bul\"},\"blim\":[{\"fim\":\"fam\"},{\"blim\":\"blam\"}]},\"arrio\":[\"himbio\"]}"));
+    }
+
+    @Test(expected=IllegalArgumentException.class)
+    public void require_that_values_are_verified_against_def() {
+        builderWithDef.setField("boolval", "true");
+        assertThat(builderWithDef.warnings().size(), is(0));
+        builderWithDef.setField("boolval", "invalid");
+        //assertThat(builderWithDef.warnings().size(), is(1));
+    }
+
+    @Test(expected=IllegalArgumentException.class)
+    public void require_that_arrays_must_exist() {
+        builderWithDef.getArray("arraydoesnotexist");
+        //assertThat(builderWithDef.warnings().size(), is(1));
+    }
+
+    @Test(expected=IllegalArgumentException.class)
+    public void require_that_structs_must_exist() {
+        builderWithDef.getObject("structdoesnotexist");
+        //assertThat(builderWithDef.warnings().size(), is(1));
+    }
+
+    @Test(expected=IllegalArgumentException.class)
+    public void require_that_definition_is_passed_to_childstruct() {
+        ConfigPayloadBuilder nestedStruct = builderWithDef.getObject("mystruct");
+        assertThat(builderWithDef.warnings().size(), is(0));
+        nestedStruct.setField("doesnotexit", "foo");
+        //assertThat(builderWithDef.warnings().size(), is(1));
+    }
+
+    @Test(expected=IllegalArgumentException.class)
+    public void require_that_definition_is_passed_to_childstruct_but_invalid_field_will_throw() {
+        ConfigPayloadBuilder nestedStruct = builderWithDef.getObject("mystruct");
+        nestedStruct.setField("foofield", "invalid");
+        //assertThat(builderWithDef.warnings().size(), is(2));
+    }
+
+    @Test
+    public void require_that_definition_is_passed_to_childarray() {
+        ConfigPayloadBuilder.Array nestedArray = builderWithDef.getArray("myarray");
+        assertThat(builderWithDef.warnings().size(), is(0));
+        nestedArray.append("1337");
+        assertThat(builderWithDef.warnings().size(), is(0));
+    }
+
+    @Test(expected=IllegalArgumentException.class)
+    public void require_that_definition_is_passed_to_childarray_but_invalid_field_will_throw() {
+        ConfigPayloadBuilder.Array nestedArray = builderWithDef.getArray("myarray");
+        nestedArray.append("invalid");
+        //assertThat(builderWithDef.warnings().size(), is(1));
+    }
+
+    @Test
+    public void require_that_definition_is_passed_to_inner_array_with_append() {
+        ConfigPayloadBuilder.Array innerArray = builderWithDef.getArray("myinnerarray");
+        assertThat(builderWithDef.warnings().size(), is(0));
+        ConfigPayloadBuilder innerStruct = innerArray.append();
+        assertNotNull(innerStruct.getConfigDefinition());
+        assertThat(builderWithDef.warnings().size(), is(0));
+        innerStruct.setField("foo", "1337");
+        assertThat(builderWithDef.warnings().size(), is(0));
+    }
+
+    @Test(expected=IllegalArgumentException.class)
+    public void require_that_definition_is_passed_to_inner_array_with_append_but_invalid_field_will_throw() {
+        ConfigPayloadBuilder.Array innerArray = builderWithDef.getArray("myinnerarray");
+        assertThat(builderWithDef.warnings().size(), is(0));
+        ConfigPayloadBuilder innerStruct = innerArray.append();
+        innerStruct.setField("foo", "invalid");
+        //assertThat(builderWithDef.warnings().size(), is(1));
+    }
+
+    @Test
+    public void require_that_definition_is_passed_to_inner_array_with_index() {
+        ConfigPayloadBuilder.Array innerArray = builderWithDef.getArray("myinnerarray");
+        assertThat(builderWithDef.warnings().size(), is(0));
+        ConfigPayloadBuilder innerStruct = innerArray.set(1);
+        assertNotNull(innerStruct.getConfigDefinition());
+        assertThat(builderWithDef.warnings().size(), is(0));
+        innerStruct.setField("foo", "1337");
+        assertThat(builderWithDef.warnings().size(), is(0));
+    }
+
+    @Test(expected=IllegalArgumentException.class)
+    public void require_that_definition_is_passed_to_inner_array_with_index_but_invalid_field_will_throw() {
+        ConfigPayloadBuilder.Array innerArray = builderWithDef.getArray("myinnerarray");
+        assertThat(builderWithDef.warnings().size(), is(0));
+        ConfigPayloadBuilder innerStruct = innerArray.set(1);
+        innerStruct.setField("foo", "invalid");
+        //assertThat(builderWithDef.warnings().size(), is(1));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/ConfigPayloadTest.java b/config/src/test/java/com/yahoo/vespa/config/ConfigPayloadTest.java
new file mode 100644
index 00000000000..1e7b66fac38
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/ConfigPayloadTest.java
@@ -0,0 +1,461 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.foo.*;
+import com.yahoo.config.codegen.DefParser;
+import com.yahoo.config.codegen.InnerCNode;
+import com.yahoo.slime.Cursor;
+import com.yahoo.slime.Slime;
+import com.yahoo.text.StringUtilities;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.io.StringReader;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.*;
+
+/**
+ * @author lulf                                               3
+ * @since 5.1
+ */
+public class ConfigPayloadTest {
+
+    @Test
+    public void test_simple_builder() throws Exception {
+        SimpletypesConfig config = createSimpletypesConfig("stringval", "abcde");
+        assertThat(config.stringval(), is("abcde"));
+    }
+
+    @Test
+    public void require_that_arrays_are_built() throws  Exception {
+        AppConfig config = createAppConfig("foo", "4", new String[] { "bar", "baz", "bim" });
+        assertThat(config.message(), is("foo"));
+        assertThat(config.times(), is(4));
+        assertThat(config.a(0).name(), is("bar"));
+        assertThat(config.a(1).name(), is("baz"));
+        assertThat(config.a(2).name(), is("bim"));
+    }
+
+    @Test
+    public void test_int_leaf_legal() throws Exception {
+        SimpletypesConfig config = createSimpletypesConfig("intval", "0");
+        assertThat(config.intval(), is(0));
+        config = createSimpletypesConfig("intval", String.valueOf(Integer.MIN_VALUE));
+        assertThat(config.intval(), is(Integer.MIN_VALUE));
+        config = createSimpletypesConfig("intval", String.valueOf(Integer.MAX_VALUE));
+        assertThat(config.intval(), is(Integer.MAX_VALUE));
+        config = createSimpletypesConfig("intval", String.valueOf(10));
+        assertThat(config.intval(), is(10));
+        config = createSimpletypesConfig("intval", String.valueOf(-10));
+        assertThat(config.intval(), is(-10));
+    }
+
+    @Test (expected = RuntimeException.class)
+    public void test_int_leaf_too_large() throws Exception {
+        createSimpletypesConfig("intval", String.valueOf(Integer.MAX_VALUE) + "00");
+    }
+
+    @Test (expected = RuntimeException.class)
+    public void test_int_leaf_too_large_neg() throws Exception {
+        createSimpletypesConfig("intval", String.valueOf(Integer.MIN_VALUE) + "00");
+    }
+
+    @Test(expected=RuntimeException.class)
+    public void test_int_leaf_illegal_string() throws Exception {
+        createSimpletypesConfig("intval", "illegal");
+    }
+
+    @Test(expected=RuntimeException.class)
+    public void test_int_leaf_illegal_string_suffix() throws Exception {
+        createSimpletypesConfig("intval", "123illegal");
+    }
+
+    @Test(expected=RuntimeException.class)
+    public void test_int_leaf_illegal_string_prefix() throws Exception {
+        createSimpletypesConfig("intval", "illegal123");
+    }
+
+    @Test
+    public void test_that_empty_is_empty() {
+        ConfigPayload payload = ConfigPayload.empty();
+        assertTrue(payload.isEmpty());
+        payload = ConfigPayload.fromString("{\"foo\":4}");
+        assertFalse(payload.isEmpty());
+    }
+
+
+    @Test
+    public void test_long_leaf() throws Exception {
+        SimpletypesConfig config = createSimpletypesConfig("longval", "0");
+        assertThat(config.longval(), is(0l));
+        config = createSimpletypesConfig("longval", String.valueOf(Long.MIN_VALUE));
+        assertThat(config.longval(), is(Long.MIN_VALUE));
+        config = createSimpletypesConfig("longval", String.valueOf(Long.MAX_VALUE));
+        assertThat(config.longval(), is(Long.MAX_VALUE));
+        config = createSimpletypesConfig("longval", String.valueOf(10));
+        assertThat(config.longval(), is(10l));
+        config = createSimpletypesConfig("longval", String.valueOf(-10));
+        assertThat(config.longval(), is(-10l));
+    }
+
+    @Test(expected = RuntimeException.class)
+    public void test_long_leaf_illegal_string() throws Exception {
+        createSimpletypesConfig("longval", "illegal");
+    }
+
+    @Test (expected = RuntimeException.class)
+    public void test_long_leaf_too_large() throws Exception {
+        createSimpletypesConfig("longval", String.valueOf(Long.MAX_VALUE) + "00");
+    }
+
+    @Test (expected = RuntimeException.class)
+    public void test_long_leaf_too_large_neg() throws Exception {
+        createSimpletypesConfig("longval", String.valueOf(Long.MIN_VALUE) + "00");
+    }
+
+    @Test
+    public void test_double_leaf() throws Exception {
+        SimpletypesConfig config = createSimpletypesConfig("doubleval", "0");
+        assertEquals(0.0, config.doubleval(), 0.01);
+        assertEquals(133.3, createSimpletypesConfig("doubleval", "133.3").doubleval(), 0.001);
+        config = createSimpletypesConfig("doubleval", String.valueOf(Double.MIN_VALUE));
+        assertEquals(Double.MIN_VALUE, config.doubleval(), 0.0000001);
+        config = createSimpletypesConfig("doubleval", String.valueOf(Double.MAX_VALUE));
+        assertEquals(Double.MAX_VALUE, config.doubleval(), 0.0000001);
+    }
+
+    @Test
+    public void test_serializer() throws IOException {
+        ConfigPayload payload = ConfigPayload.fromInstance(new SimpletypesConfig(new SimpletypesConfig.Builder()));
+        assertThat(payload.toString(true), is("{\"boolval\":false,\"doubleval\":0.0,\"enumval\":\"VAL1\",\"intval\":0,\"longval\":0,\"stringval\":\"s\"}"));
+    }
+
+    @Test(expected=RuntimeException.class)
+    public void test_double_leaf_illegal_string() throws Exception {
+        createSimpletypesConfig("doubleval", "illegal");
+    }
+
+    @Test
+    public void test_double_leaf_negative_infinity() throws Exception {
+        assertThat(createSimpletypesConfig("doubleval", "-Infinity").doubleval(), is(Double.NEGATIVE_INFINITY));
+        assertThat(createSimpletypesConfig("doubleval", "Infinity").doubleval(), is(Double.POSITIVE_INFINITY));
+    }
+
+    @Test
+    public void test_enum_leaf() throws Exception {
+        assertThat(createSimpletypesConfig("enumval", "VAL1").enumval(), is(SimpletypesConfig.Enumval.Enum.VAL1));
+        assertThat(createSimpletypesConfig("enumval", "VAL2").enumval(), is(SimpletypesConfig.Enumval.Enum.VAL2));
+    }
+
+    @Test(expected=RuntimeException.class)
+    public void test_enum_leaf_illegal_string() throws Exception {
+        createSimpletypesConfig("enumval", "ILLEGAL");
+    }
+
+    @Test
+    public void test_bool_leaf() throws Exception {
+        SimpletypesConfig config = createSimpletypesConfig("boolval", "true");
+        assertThat(config.boolval(), is(true));
+        config = createSimpletypesConfig("boolval", "false");
+        assertThat(config.boolval(), is(false));
+        config = createSimpletypesConfig("boolval", "TRUE");
+        assertThat(config.boolval(), is(true));
+        config = createSimpletypesConfig("boolval", "FALSE");
+        assertThat(config.boolval(), is(false));
+    }
+
+    @Test// FIXME: (expected = RuntimeException.class)
+    public void test_bool_leaf_illegal() throws Exception {
+        createSimpletypesConfig("boolval", "illegal");
+    }
+
+    @Test
+    public void test_string_illegal_value() throws Exception {
+        // TODO: What do we consider illegal string values?
+        createSimpletypesConfig("stringval", "insert_illegal_value_please");
+    }
+
+    @Test
+    public void test_int_array() throws Exception {
+        // Normal behavior
+        ArraytypesConfig config = createArraytypesConfig("intarr", new String[] { "2", "3", "1", "-2", "5"});
+        assertThat(config.intarr().size(),  is(5));
+        assertThat(config.intarr(0), is(2));
+        assertThat(config.intarr(1), is(3));
+        assertThat(config.intarr(2), is(1));
+        assertThat(config.intarr(3), is(-2));
+        assertThat(config.intarr(4), is(5));
+
+        final int size = 100;
+        String [] largeArray = new String[size];
+        for (int i = 0; i < size; i++) {
+            int value = (int)(Math.random() * Integer.MAX_VALUE);
+            largeArray[i] = String.valueOf(value);
+        }
+        config = createArraytypesConfig("intarr", largeArray);
+        assertThat(config.intarr().size(), is(largeArray.length));
+        for (int i = 0; i < size; i++) {
+            assertThat(config.intarr(i), is(Integer.valueOf(largeArray[i])));
+        }
+    }
+
+    @Test(expected = RuntimeException.class)
+    public void test_int_array_illegal() throws Exception {
+        createArraytypesConfig("intarr", new String[] { "2", "3", "illegal", "-2", "5"});
+    }
+
+    @Test
+    public void test_long_array() throws Exception {
+        // Normal behavior
+        ArraytypesConfig config = createArraytypesConfig("longarr", new String[] { "2", "3", "1", "-2", "5"});
+        assertThat(config.longarr().size(),  is(5));
+        assertThat(config.longarr(0), is(2l));
+        assertThat(config.longarr(1), is(3l));
+        assertThat(config.longarr(2), is(1l));
+        assertThat(config.longarr(3), is(-2l));
+        assertThat(config.longarr(4), is(5l));
+
+        final int size = 100;
+        String [] largeArray = new String[size];
+        for (int i = 0; i < size; i++) {
+            long value = (long) (Math.random() * Long.MAX_VALUE);
+            largeArray[i] = String.valueOf(value);
+        }
+        config = createArraytypesConfig("longarr", largeArray);
+        assertThat(config.longarr().size(), is(largeArray.length));
+        for (int i = 0; i < size; i++) {
+            assertThat(config.longarr(i), is(Long.valueOf(largeArray[i])));
+        }
+    }
+
+    @Test
+    public void test_double_array() throws Exception {
+        // Normal behavior
+        ArraytypesConfig config = createArraytypesConfig("doublearr", new String[] { "2.1", "3.3", "1.5", "-2.1", "Infinity"});
+        assertThat(config.doublearr().size(),  is(5));
+        assertEquals(2.1, config.doublearr(0), 0.01);
+        assertEquals(3.3, config.doublearr(1), 0.01);
+        assertEquals(1.5, config.doublearr(2), 0.01);
+        assertEquals(-2.1, config.doublearr(3), 0.01);
+        assertEquals(Double.POSITIVE_INFINITY, config.doublearr(4), 0.01);
+    }
+
+    @Test
+    public void test_enum_array() throws Exception {
+        // Normal behavior
+        ArraytypesConfig config = createArraytypesConfig("enumarr", new String[] { "VAL1", "VAL2", "VAL1" });
+        assertThat(config.enumarr().size(),  is(3));
+        assertThat(config.enumarr(0), is(ArraytypesConfig.Enumarr.Enum.VAL1));
+        assertThat(config.enumarr(1), is(ArraytypesConfig.Enumarr.Enum.VAL2));
+        assertThat(config.enumarr(2), is(ArraytypesConfig.Enumarr.Enum.VAL1));
+    }
+
+    @Test
+    public void test_simple_struct() throws Exception {
+        StructtypesConfig config = createStructtypesConfigSimple("foobar", "MALE", new String[] { "foo@bar", "bar@foo" });
+        assertThat(config.simple().name(), is("foobar"));
+        assertThat(config.simple().gender(), is(StructtypesConfig.Simple.Gender.Enum.MALE));
+        assertThat(config.simple().emails(0), is("foo@bar"));
+        assertThat(config.simple().emails(1), is("bar@foo"));
+    }
+
+
+    @Test
+    public void test_simple_struct_arrays() throws Exception {
+        StructtypesConfig config = createStructtypesConfigArray(new String[] { "foo", "bar" },
+                                                                new String[] { "MALE", "FEMALE" });
+        assertThat(config.simplearr(0).name(), is("foo"));
+        assertThat(config.simplearr(0).gender(), is(StructtypesConfig.Simplearr.Gender.MALE));
+        assertThat(config.simplearr(1).name(), is("bar"));
+        assertThat(config.simplearr(1).gender(), is(StructtypesConfig.Simplearr.Gender.FEMALE));
+    }
+
+
+    @Test
+    public void test_nested_struct() throws  Exception {
+        StructtypesConfig config = createStructtypesConfigNested("foo", "FEMALE");
+        assertThat(config.nested().inner().name(), is("foo"));
+        assertThat(config.nested().inner().gender(), is(StructtypesConfig.Nested.Inner.Gender.Enum.FEMALE));
+    }
+
+
+
+    @Test
+    public void test_nested_struct_array() throws  Exception {
+        String [] names = { "foo" ,"bar" };
+        String [] genders = { "FEMALE", "MALE" };
+        String [][] emails = {
+                { "foo@bar" , "bar@foo" },
+                { "bim@bam", "bam@bim" }
+        };
+        StructtypesConfig config = createStructtypesConfigNestedArray(names, genders, emails);
+        assertThat(config.nestedarr(0).inner().name(), is("foo"));
+        assertThat(config.nestedarr(0).inner().gender(), is(StructtypesConfig.Nestedarr.Inner.Gender.FEMALE));
+        assertThat(config.nestedarr(0).inner().emails(0), is("foo@bar"));
+        assertThat(config.nestedarr(0).inner().emails(1), is("bar@foo"));
+
+        assertThat(config.nestedarr(1).inner().name(), is("bar"));
+        assertThat(config.nestedarr(1).inner().gender(), is(StructtypesConfig.Nestedarr.Inner.Gender.MALE));
+        assertThat(config.nestedarr(1).inner().emails(0), is("bim@bam"));
+        assertThat(config.nestedarr(1).inner().emails(1), is("bam@bim"));
+    }
+
+
+    @Test
+    public void test_complex_struct_array() throws  Exception  {
+        String [][] names = {
+                { "foo", "bar" },
+                { "baz", "bim" }
+        };
+        String [][] genders = {
+                { "FEMALE", "MALE" },
+                { "MALE", "FEMALE" }
+        };
+        StructtypesConfig config = createStructtypesConfigComplexArray(names, genders);
+        assertThat(config.complexarr(0).innerarr(0).name(), is("foo"));
+        assertThat(config.complexarr(0).innerarr(0).gender(), is(StructtypesConfig.Complexarr.Innerarr.Gender.Enum.FEMALE));
+        assertThat(config.complexarr(0).innerarr(1).name(), is("bar"));
+        assertThat(config.complexarr(0).innerarr(1).gender(), is(StructtypesConfig.Complexarr.Innerarr.Gender.Enum.MALE));
+
+        assertThat(config.complexarr(1).innerarr(0).name(), is("baz"));
+        assertThat(config.complexarr(1).innerarr(0).gender(), is(StructtypesConfig.Complexarr.Innerarr.Gender.Enum.MALE));
+        assertThat(config.complexarr(1).innerarr(1).name(), is("bim"));
+        assertThat(config.complexarr(1).innerarr(1).gender(), is(StructtypesConfig.Complexarr.Innerarr.Gender.Enum.FEMALE));
+    }
+
+    @Test
+    public void test_function_test() {
+        // TODO: Test function test config as a complete config example
+    }
+
+    @Test
+    public void test_set_nonexistent_field() throws Exception {
+        createSimpletypesConfig("doesnotexist", "blabla");
+    }
+
+    @Test
+    public void test_escaped_string() throws Exception {
+        SimpletypesConfig config = createSimpletypesConfig("stringval", "b=\"escaped\"");
+        assertThat(config.stringval(), is("b=\"escaped\""));
+    }
+
+    @Test
+    public void test_unicode() throws Exception {
+        SimpletypesConfig config = createSimpletypesConfig("stringval", "Hei \u00E6\u00F8\u00E5 \uBC14\uB451 \u00C6\u00D8\u00C5 hallo");
+        assertThat(config.stringval(), is("Hei \u00E6\u00F8\u00E5 \uBC14\uB451 \u00C6\u00D8\u00C5 hallo"));
+    }
+
+    @Test
+    public void test_empty_payload() throws Exception {
+        Slime slime = new Slime();
+        slime.setObject();
+        IntConfig config = new ConfigPayload(slime).toInstance(IntConfig.class, "");
+        assertThat(config.intVal(), is(1));
+    }
+
+    @Test
+    public void test_applying_extra_default_values() {
+        InnerCNode clientDef = new DefParser(SimpletypesConfig.CONFIG_DEF_NAME, new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n") + "\nnewfield int default=3\n")).getTree();
+        ConfigPayload payload = ConfigPayload.fromInstance(new SimpletypesConfig(new SimpletypesConfig.Builder()));
+        payload = payload.applyDefaultsFromDef(clientDef);
+        assertThat(payload.toString(true), is("{\"boolval\":false,\"doubleval\":0.0,\"enumval\":\"VAL1\",\"intval\":0,\"longval\":0,\"stringval\":\"s\",\"newfield\":\"3\"}"));
+    }
+
+    /**
+     * TODO: Test invalid slime trees?
+     * TODO: Test sending in wrong class
+     */
+
+    /**********************************************************************************************
+     * Helper methods. consider moving out to another class for reuse by merge tester.            *
+     **********************************************************************************************/
+    private AppConfig createAppConfig(String message, String times, String [] names) {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("message", message);
+        root.setString("times", times);
+        Cursor arr = root.setArray("a");
+        for (String name : names) {
+            Cursor obj = arr.addObject();
+            obj.setString("name", name);
+        }
+        return new ConfigPayload(slime).toInstance(AppConfig.class, "");
+    }
+
+    private SimpletypesConfig createSimpletypesConfig(String field, String value) {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString(field, value);
+        return new ConfigPayload(slime).toInstance(SimpletypesConfig.class, "");
+    }
+
+    private ArraytypesConfig createArraytypesConfig(String field, String [] values) {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        Cursor array = root.setArray(field);
+        for (String value : values) {
+            array.addString(value);
+        }
+        return new ConfigPayload(slime).toInstance(ArraytypesConfig.class, "");
+    }
+
+
+    private void addStructFields(Cursor struct, String name, String gender, String [] emails) {
+        struct.setString("name", name);
+        struct.setString("gender", gender);
+        if (emails != null) {
+            Cursor array = struct.setArray("emails");
+            for (String email : emails) {
+                array.addString(email);
+            }
+        }
+    }
+
+    private StructtypesConfig createStructtypesConfigSimple(String name, String gender, String [] emails) {
+        Slime slime = new Slime();
+        addStructFields(slime.setObject().setObject("simple"), name, gender, emails);
+        return new ConfigPayload(slime).toInstance(StructtypesConfig.class, "");
+    }
+
+    private StructtypesConfig createStructtypesConfigArray(String[] names, String[] genders) {
+        Slime slime = new Slime();
+        Cursor array = slime.setObject().setArray("simplearr");
+        assertEquals(names.length, genders.length);
+        for (int i = 0; i < names.length; i++) {
+            addStructFields(array.addObject(), names[i], genders[i], null);
+        }
+        return new ConfigPayload(slime).toInstance(StructtypesConfig.class, "");
+    }
+
+    private StructtypesConfig createStructtypesConfigNested(String name, String gender) {
+        Slime slime = new Slime();
+        addStructFields(slime.setObject().setObject("nested").setObject("inner"), name, gender, null);
+        return new ConfigPayload(slime).toInstance(StructtypesConfig.class, "");
+    }
+
+    private StructtypesConfig createStructtypesConfigNestedArray(String[] names, String [] genders, String [][] emails) {
+        Slime slime = new Slime();
+        Cursor array = slime.setObject().setArray("nestedarr");
+        assertEquals(names.length, genders.length);
+        for (int i = 0; i < names.length; i++) {
+            addStructFields(array.addObject().setObject("inner"), names[i], genders[i], emails[i]);
+        }
+        return new ConfigPayload(slime).toInstance(StructtypesConfig.class, "");
+    }
+
+    private StructtypesConfig createStructtypesConfigComplexArray(String [][] names, String [][] genders) {
+        Slime slime = new Slime();
+        Cursor array = slime.setObject().setArray("complexarr");
+        assertEquals(names.length, genders.length);
+        for (int i = 0; i < names.length; i++) {
+            assertEquals(names[i].length, genders[i].length);
+
+            Cursor innerarr = array.addObject().setArray("innerarr");
+            for (int k = 0; k < names[i].length; k++) {
+                addStructFields(innerarr.addObject(), names[i][k], genders[i][k], null);
+            }
+        }
+        return new ConfigPayload(slime).toInstance(StructtypesConfig.class, "");
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/DefaultValueApplierTest.java b/config/src/test/java/com/yahoo/vespa/config/DefaultValueApplierTest.java
new file mode 100644
index 00000000000..623d81993d9
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/DefaultValueApplierTest.java
@@ -0,0 +1,100 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.codegen.DefParser;
+import com.yahoo.config.codegen.InnerCNode;
+import com.yahoo.slime.Cursor;
+import com.yahoo.slime.Slime;
+import com.yahoo.slime.Type;
+import org.junit.Test;
+
+import java.io.StringReader;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author lulf
+ * @since 5.1
+ */
+public class DefaultValueApplierTest {
+    public Slime apply(Slime slime, String ... extraFields) {
+        StringBuilder defBuilder = new StringBuilder();
+        defBuilder.append("namespace=test").append("\n");
+        defBuilder.append("str string").append("\n");
+        for (String field : extraFields) {
+            defBuilder.append(field).append("\n");
+        }
+        Cursor cursor = slime.get();
+        cursor.setString("str", "myvalue");
+        InnerCNode def = new DefParser("simpletypes", new StringReader(defBuilder.toString())).getTree();
+        DefaultValueApplier applier = new DefaultValueApplier();
+        return applier.applyDefaults(slime, def);
+    }
+
+    public Slime apply(String ... extraFields) {
+        Slime slime = new Slime();
+        slime.setObject();
+        return apply(slime, extraFields);
+    }
+
+    @Test
+    public void require_that_simple_defaults_are_applied() {
+        Slime slime = apply("strdef string default=\"foo\"");
+        assertTrue(slime.get().field("str").valid());
+        assertThat(slime.get().field("str").asString(), is("myvalue"));
+        assertTrue(slime.get().field("strdef").valid());
+        assertThat(slime.get().field("strdef").asString(), is("foo"));
+
+    }
+
+    @Test
+    public void require_that_struct_fields_defaults_are_applied() {
+        Slime slime = apply("nested.str string default=\"bar\"");
+        assertTrue(slime.get().field("nested").valid());
+        assertTrue(slime.get().field("nested").field("str").valid());
+        assertThat(slime.get().field("nested").field("str").asString(), is("bar"));
+    }
+
+    @Test
+    public void require_that_arrays_of_struct_fields_defaults_are_applied() {
+        Slime payload = new Slime();
+        Cursor cursor = payload.setObject();
+        cursor.setArray("nestedarr").addObject().setString("foo", "myfoo");
+        Slime slime = apply(payload, "nestedarr[].foo string", "nestedarr[].bar string default=\"bim\"");
+
+        assertTrue(slime.get().field("nestedarr").valid());
+        assertThat(slime.get().field("nestedarr").entries(), is(1));
+        assertTrue(slime.get().field("nestedarr").entry(0).field("foo").valid());
+        assertThat(slime.get().field("nestedarr").entry(0).field("foo").asString(), is("myfoo"));
+        assertTrue(slime.get().field("nestedarr").entry(0).field("bar").valid());
+        assertThat(slime.get().field("nestedarr").entry(0).field("bar").asString(), is("bim"));
+    }
+
+    @Test
+    public void require_that_arrays_of_struct_fields_defaults_when_empty() {
+        Slime payload = new Slime();
+        payload.setObject();
+        Slime slime = apply(payload, "nestedarr[].foo string", "nestedarr[].bar string default=\"bim\"");
+
+        assertTrue(slime.get().field("nestedarr").valid());
+        assertThat(slime.get().field("nestedarr").entries(), is(0));
+        assertThat(slime.get().field("nestedarr").type(), is(Type.ARRAY));
+    }
+
+    @Test
+    public void require_that_maps_of_struct_fields_defaults_are_applied() {
+        Slime payload = new Slime();
+        Cursor cursor = payload.setObject();
+        cursor.setObject("nestedmap").setObject("mykey").setString("foo", "myfoo");
+        Slime slime = apply(payload, "nestedmap{}.foo string", "nestedmap{}.bar string default=\"bim\"");
+
+        assertTrue(slime.get().field("nestedmap").valid());
+        assertThat(slime.get().field("nestedmap").fields(), is(1));
+        assertTrue(slime.get().field("nestedmap").field("mykey").field("foo").valid());
+        assertThat(slime.get().field("nestedmap").field("mykey").field("foo").asString(), is("myfoo"));
+        assertTrue(slime.get().field("nestedmap").field("mykey").field("bar").valid());
+        assertThat(slime.get().field("nestedmap").field("mykey").field("bar").asString(), is("bim"));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/ErrorCodeTest.java b/config/src/test/java/com/yahoo/vespa/config/ErrorCodeTest.java
new file mode 100644
index 00000000000..249a5ab6123
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/ErrorCodeTest.java
@@ -0,0 +1,35 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import org.junit.Test;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author <a href="mailto:musum@yahoo-inc.com">Harald Musum</a>
+ * @since 5.1.9
+ */
+public class ErrorCodeTest {
+    @Test
+    public void basic() {
+        assertThat(ErrorCode.getName(ErrorCode.INTERNAL_ERROR), is("INTERNAL_ERROR"));
+        assertThat(ErrorCode.getName(ErrorCode.ILLEGAL_CONFIG_MD5), is("ILLEGAL_CONFIG_MD5"));
+        assertThat(ErrorCode.getName(ErrorCode.ILLEGAL_CONFIGID), is("ILLEGAL_CONFIGID"));
+        assertThat(ErrorCode.getName(ErrorCode.ILLEGAL_DEF_MD5), is("ILLEGAL_DEF_MD5"));
+        assertThat(ErrorCode.getName(ErrorCode.ILLEGAL_GENERATION), is("ILLEGAL_GENERATION"));
+        assertThat(ErrorCode.getName(ErrorCode.ILLEGAL_NAME), is("ILLEGAL_NAME"));
+        assertThat(ErrorCode.getName(ErrorCode.ILLEGAL_SUB_FLAG), is("ILLEGAL_SUBSCRIBE_FLAG"));
+        assertThat(ErrorCode.getName(ErrorCode.ILLEGAL_TIMEOUT), is("ILLEGAL_TIMEOUT"));
+        assertThat(ErrorCode.getName(ErrorCode.ILLEGAL_VERSION), is("ILLEGAL_VERSION"));
+        assertThat(ErrorCode.getName(ErrorCode.OUTDATED_CONFIG), is("OUTDATED_CONFIG"));
+        assertThat(ErrorCode.getName(ErrorCode.UNKNOWN_CONFIG), is("UNKNOWN_CONFIG"));
+        assertThat(ErrorCode.getName(ErrorCode.UNKNOWN_DEF_MD5), is("UNKNOWN_DEF_MD5"));
+        assertThat(ErrorCode.getName(ErrorCode.UNKNOWN_DEFINITION), is("UNKNOWN_DEFINITION"));
+        assertThat(ErrorCode.getName(ErrorCode.UNKNOWN_VESPA_VERSION), is("UNKNOWN_VESPA_VERSION"));
+        assertThat(ErrorCode.getName(ErrorCode.INCONSISTENT_CONFIG_MD5), is("INCONSISTENT_CONFIG_MD5"));
+        assertThat(ErrorCode.getName(ErrorCode.ILLEGAL_CLIENT_HOSTNAME), is("ILLEGAL_CLIENT_HOSTNAME"));
+
+        assertThat(ErrorCode.getName(12345), is("Unknown error"));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/ErrorTypeTest.java b/config/src/test/java/com/yahoo/vespa/config/ErrorTypeTest.java
new file mode 100644
index 00000000000..d8af6584eca
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/ErrorTypeTest.java
@@ -0,0 +1,35 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import org.junit.Test;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author lulf
+ * @since 5.1
+ */
+public class ErrorTypeTest {
+
+    @Test
+    public void testErrorType() {
+        assertThat(ErrorType.getErrorType(com.yahoo.jrt.ErrorCode.CONNECTION), is(ErrorType.TRANSIENT));
+        assertThat(ErrorType.getErrorType(com.yahoo.jrt.ErrorCode.TIMEOUT), is(ErrorType.TRANSIENT));
+        assertThat(ErrorType.getErrorType(ErrorCode.UNKNOWN_CONFIG), is(ErrorType.FATAL));
+        assertThat(ErrorType.getErrorType(ErrorCode.UNKNOWN_DEFINITION), is(ErrorType.FATAL));
+        assertThat(ErrorType.getErrorType(ErrorCode.UNKNOWN_DEF_MD5), is(ErrorType.FATAL));
+        assertThat(ErrorType.getErrorType(ErrorCode.ILLEGAL_NAME), is(ErrorType.FATAL));
+        assertThat(ErrorType.getErrorType(ErrorCode.ILLEGAL_VERSION), is(ErrorType.FATAL));
+        assertThat(ErrorType.getErrorType(ErrorCode.ILLEGAL_CONFIGID), is(ErrorType.FATAL));
+        assertThat(ErrorType.getErrorType(ErrorCode.ILLEGAL_DEF_MD5), is(ErrorType.FATAL));
+        assertThat(ErrorType.getErrorType(ErrorCode.ILLEGAL_CONFIG_MD5), is(ErrorType.FATAL));
+        assertThat(ErrorType.getErrorType(ErrorCode.ILLEGAL_TIMEOUT), is(ErrorType.FATAL));
+        assertThat(ErrorType.getErrorType(ErrorCode.ILLEGAL_GENERATION), is(ErrorType.FATAL));
+        assertThat(ErrorType.getErrorType(ErrorCode.ILLEGAL_SUB_FLAG), is(ErrorType.FATAL));
+        assertThat(ErrorType.getErrorType(ErrorCode.OUTDATED_CONFIG), is(ErrorType.FATAL));
+        assertThat(ErrorType.getErrorType(ErrorCode.INTERNAL_ERROR), is(ErrorType.FATAL));
+        assertThat(ErrorType.getErrorType(ErrorCode.ILLEGAL_SUB_FLAG), is(ErrorType.FATAL));
+        assertThat(ErrorType.getErrorType(0xdeadc0de), is(ErrorType.FATAL));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/GenericConfigBuilderTest.java b/config/src/test/java/com/yahoo/vespa/config/GenericConfigBuilderTest.java
new file mode 100644
index 00000000000..f745c70fe1b
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/GenericConfigBuilderTest.java
@@ -0,0 +1,48 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.subscription.ConfigInstanceUtil;
+import com.yahoo.slime.JsonFormat;
+import org.junit.Test;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author lulf
+ * @since 5.1
+ */
+public class GenericConfigBuilderTest {
+    @Test
+    public void require_that_builder_can_be_overridden() throws IOException {
+        ConfigPayloadBuilder ba = new ConfigPayloadBuilder();
+        ba.setField("foo", "bar");
+        ConfigPayloadBuilder bb = new ConfigPayloadBuilder();
+        bb.setField("foo", "baz");
+        ConfigPayloadBuilder bc = new ConfigPayloadBuilder();
+        bc.setField("foo", "bim");
+        GenericConfig.GenericConfigBuilder a = new GenericConfig.GenericConfigBuilder(null, ba);
+        GenericConfig.GenericConfigBuilder b = new GenericConfig.GenericConfigBuilder(null, bb);
+        GenericConfig.GenericConfigBuilder c = new GenericConfig.GenericConfigBuilder(null, bc);
+        assertThat(getString(a), is("{\"foo\":\"bar\"}"));
+        assertThat(getString(b), is("{\"foo\":\"baz\"}"));
+        assertThat(getString(c), is("{\"foo\":\"bim\"}"));
+        ConfigInstanceUtil.setValues(a, b);
+        assertThat(getString(a), is("{\"foo\":\"baz\"}"));
+        assertThat(getString(b), is("{\"foo\":\"baz\"}"));
+        assertThat(getString(c), is("{\"foo\":\"bim\"}"));
+        ConfigInstanceUtil.setValues(c, a);
+        assertThat(getString(a), is("{\"foo\":\"baz\"}"));
+        assertThat(getString(b), is("{\"foo\":\"baz\"}"));
+        assertThat(getString(c), is("{\"foo\":\"baz\"}"));
+    }
+
+    private String getString(GenericConfig.GenericConfigBuilder builder) throws IOException {
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        builder.getPayload().serialize(baos, new JsonFormat(true));
+        return baos.toString();
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/JRTConnectionPoolTest.java b/config/src/test/java/com/yahoo/vespa/config/JRTConnectionPoolTest.java
new file mode 100644
index 00000000000..438d8edb430
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/JRTConnectionPoolTest.java
@@ -0,0 +1,124 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.subscription.ConfigSourceSet;
+import org.junit.Test;
+
+import java.util.*;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.not;
+import static org.junit.Assert.*;
+
+/**
+ * Tests for the JRTConnectionPool class.
+ *
+ * @author <a href="mailto:gunnarga@yahoo-inc.com">Gunnar Gauslaa Bergem</a>
+ * @author musum
+ */
+public class JRTConnectionPoolTest {
+    private static final List<String> sources = new ArrayList<>((Arrays.asList("host0", "host1", "host2")));
+
+    /**
+     * Tests that hash-based selection through the list works.
+     */
+    @Test
+    public void test_random_selection_of_sourceBasicHashBasedSelection() {
+        JRTConnectionPool sourcePool = new JRTConnectionPool(sources);
+        assertThat(sourcePool.toString(), is("Address: host0\nAddress: host1\nAddress: host2\n"));
+
+        Map<String, Integer> sourceOccurrences = new HashMap<>();
+        for (int i = 0; i < 1000; i++) {
+            final String address = sourcePool.setNewCurrentConnection().getAddress();
+            if (sourceOccurrences.containsKey(address)) {
+                sourceOccurrences.put(address, sourceOccurrences.get(address) + 1);
+            } else {
+                sourceOccurrences.put(address, 1);
+            }
+        }
+        for (int i = 0; i < sourcePool.getSize(); i++) {
+            assertTrue(sourceOccurrences.get(sourcePool.getSources().get(i).getAddress()) > 200);
+        }
+    }
+
+    /**
+     * Tests that when there are two sources and several clients
+     * the sources will be chosen with about the same probability.
+     */
+    @Test
+    public void testManySources() {
+        Map<String, Integer> timesUsed = new LinkedHashMap<>();
+
+        List<String> twoSources = new ArrayList<>();
+
+        twoSources.add("host0");
+        twoSources.add("host1");
+        JRTConnectionPool sourcePool = new JRTConnectionPool(twoSources);
+
+        int count = 1000;
+        for (int i = 0; i < count; i++) {
+            String address = sourcePool.setNewCurrentConnection().getAddress();
+            if (timesUsed.containsKey(address)) {
+                int times = timesUsed.get(address);
+                timesUsed.put(address, times + 1);
+            } else {
+                timesUsed.put(address, 1);
+            }
+        }
+        assertConnectionDistributionIsFair(timesUsed);
+    }
+
+    // Tests that the number of times each connection is used is close to equal
+    private void assertConnectionDistributionIsFair(Map<String, Integer> connectionsUsedPerHost) {
+        double devianceDueToRandomSourceSelection = 0.13;
+        final int size = 1000;
+        int minHostCount = (int) (size/2 * (1 - devianceDueToRandomSourceSelection));
+        int maxHostCount = (int) (size/2 * (1 + devianceDueToRandomSourceSelection));
+
+        for (Map.Entry<String, Integer> entry : connectionsUsedPerHost.entrySet()) {
+            Integer timesUsed = entry.getValue();
+            assertTrue("Host 0 used " + timesUsed + " times, expected to be < " + maxHostCount, timesUsed < maxHostCount);
+            assertTrue("Host 0 used " + timesUsed + " times, expected to be > " + minHostCount, timesUsed > minHostCount);
+        }
+    }
+
+    /**
+     * Tests that updating config sources works.
+     */
+    @Test
+    public void updateSources() {
+        List<String> twoSources = new ArrayList<>();
+
+        twoSources.add("host0");
+        twoSources.add("host1");
+        JRTConnectionPool sourcePool = new JRTConnectionPool(twoSources);
+
+        ConfigSourceSet sourcesBefore = sourcePool.getSourceSet();
+
+        // Update to the same set, should be equal
+        sourcePool.updateSources(twoSources);
+        assertThat(sourcesBefore, is(sourcePool.getSourceSet()));
+
+        // Update to new set
+        List<String> newSources = new ArrayList<>();
+        newSources.add("host2");
+        newSources.add("host3");
+        sourcePool.updateSources(newSources);
+        ConfigSourceSet newSourceSet = sourcePool.getSourceSet();
+        assertNotNull(newSourceSet);
+        assertThat(newSourceSet.getSources().size(), is(2));
+        assertThat(newSourceSet, is(not(sourcesBefore)));
+        assertTrue(newSourceSet.getSources().contains("host2"));
+        assertTrue(newSourceSet.getSources().contains("host3"));
+
+        // Update to new set with just one host
+        List<String> newSources2 = new ArrayList<>();
+        newSources2.add("host4");
+        sourcePool.updateSources(newSources2);
+        ConfigSourceSet newSourceSet2 = sourcePool.getSourceSet();
+        assertNotNull(newSourceSet2);
+        assertThat(newSourceSet2.getSources().size(), is(1));
+        assertThat(newSourceSet2, is(not(newSourceSet)));
+        assertTrue(newSourceSet2.getSources().contains("host4"));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/LZ4CompressionTest.java b/config/src/test/java/com/yahoo/vespa/config/LZ4CompressionTest.java
new file mode 100644
index 00000000000..5fb7c7a9a97
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/LZ4CompressionTest.java
@@ -0,0 +1,74 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import net.jpountz.lz4.LZ4Compressor;
+import net.jpountz.lz4.LZ4Factory;
+import net.jpountz.lz4.LZ4SafeDecompressor;
+import org.junit.Ignore;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.nio.file.FileSystems;
+import java.nio.file.Files;
+
+/**
+ * To run this test, place a payload in src/test/ca.json. The file is not checked in because it is huge.
+ *
+ * @author lulf
+ * @since 5.12
+ */
+public class LZ4CompressionTest {
+    private static LZ4Factory factory = LZ4Factory.safeInstance();
+
+    @Test
+    @Ignore
+    public void testCompression() throws IOException {
+        byte[] data = getInput();
+        System.out.println("High compressor");
+        for (int i = 0; i < 10; i++) {
+            timeCompressor(factory.highCompressor(), data);
+        }
+        System.out.println("Fast compressor");
+        for (int i = 0; i < 10; i++) {
+            timeCompressor(factory.fastCompressor(), data);
+        }
+    }
+
+    private byte[] getInput() throws IOException {
+        byte[] data = Files.readAllBytes(FileSystems.getDefault().getPath("src/test/ca.json"));
+        System.out.println("Input size: " + data.length);
+        return data;
+    }
+
+    private void timeCompressor(LZ4Compressor lz4Compressor, byte[] data) {
+        long start = System.currentTimeMillis();
+        byte[] compressed = lz4Compressor.compress(data);
+        long end = System.currentTimeMillis();
+        System.out.println("Compression took " + (end - start) + " millis, and size of data is " + compressed.length + " bytes");
+    }
+
+    @Test
+    @Ignore
+    public void testDecompression() throws IOException {
+        byte[] data = getInput();
+        byte[] outputbuffer = new byte[data.length];
+        byte[] hcCompressedData = factory.highCompressor().compress(data);
+        System.out.println("High compressor");
+        for (int i = 0; i < 10; i++) {
+            timeDecompressor(hcCompressedData, factory.safeDecompressor(), outputbuffer);
+        }
+        byte[] fastCompressedData = factory.fastCompressor().compress(data);
+        System.out.println("Fast compressor");
+        for (int i = 0; i < 10; i++) {
+            timeDecompressor(fastCompressedData, factory.safeDecompressor(), outputbuffer);
+        }
+    }
+
+    private void timeDecompressor(byte[] compressedData, LZ4SafeDecompressor decompressor, byte[] outputbuffer) {
+        long start = System.currentTimeMillis();
+        decompressor.decompress(compressedData, outputbuffer);
+        long end = System.currentTimeMillis();
+        System.out.println("Decompression took " + (end - start) + " millis");
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/LZ4PayloadCompressorTest.java b/config/src/test/java/com/yahoo/vespa/config/LZ4PayloadCompressorTest.java
new file mode 100644
index 00000000000..4b5e5ae07fe
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/LZ4PayloadCompressorTest.java
@@ -0,0 +1,30 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.text.Utf8;
+import org.junit.Test;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author lulf
+ * @since 5.19
+ */
+public class LZ4PayloadCompressorTest {
+    @Test
+    public void testCompression() {
+        assertCompression("hei hallo der");
+        assertCompression("");
+        assertCompression("{}");
+    }
+
+    private void assertCompression(String input) {
+        LZ4PayloadCompressor compressor = new LZ4PayloadCompressor();
+        byte[] data = Utf8.toBytes(input);
+        byte[] compressed = compressor.compress(data);
+        byte[] output = new byte[data.length];
+        compressor.decompress(compressed, output);
+        assertThat(data, is(output));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/RawConfigTest.java b/config/src/test/java/com/yahoo/vespa/config/RawConfigTest.java
new file mode 100644
index 00000000000..7a316838334
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/RawConfigTest.java
@@ -0,0 +1,123 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.text.Utf8String;
+import com.yahoo.vespa.config.protocol.*;
+import com.yahoo.vespa.config.protocol.VespaVersion;
+import com.yahoo.vespa.config.util.ConfigUtils;
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Optional;
+
+import static junit.framework.TestCase.assertEquals;
+import static junit.framework.TestCase.assertNull;
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.not;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertFalse;
+
+/**
+ * @author <a href="mailto:musum@yahoo-inc.com">Harald Musum</a>
+ * @since 5.1.9
+ */
+public class RawConfigTest {
+
+    private static final ConfigKey<?> key = new ConfigKey<>("foo", "id", "bar");
+    private static List<String> defContent = Arrays.asList("version=1", "anInt int");
+    private static final String defMd5 = ConfigUtils.getDefMd5FromRequest("", defContent);
+    private static final String configMd5 = "012345";
+    private static Payload payload = Payload.from(new Utf8String("anInt 1"), CompressionInfo.uncompressed());
+    private static long generation = 1L;
+
+    @Test
+    public void basic() {
+        RawConfig config = new RawConfig(key, defMd5);
+        assertEquals(config.getKey(), key);
+        assertThat(config.getDefMd5(), is(defMd5));
+        assertThat(config.getName(), is("foo"));
+        assertThat(config.getDefNamespace(), is("bar"));
+        assertThat(config.getConfigId(), is("id"));
+
+        assertThat(config.isError(), is(false));
+
+        // Copy constructor
+        RawConfig copiedConfig = new RawConfig(config);
+        assertThat(copiedConfig, is(config));
+
+        assertThat(config.toString(), is("bar.foo," + defMd5 + ",id,,0,null"));
+        assertThat(config.getVespaVersion(), is(Optional.empty()));
+    }
+
+    @Test
+    public void testEquals() {
+        RawConfig config = new RawConfig(key, defMd5);
+
+        assertThat(config, is(new RawConfig(key, defMd5)));
+        assertThat(config, is(not(new RawConfig(key, "a")))); // different def md5
+        assertThat(config.hashCode(), is(new RawConfig(key, defMd5).hashCode()));
+        assertThat(config.hashCode(), is(not(new RawConfig(key, "a").hashCode()))); // different def md5
+
+        // different generation
+        config = new RawConfig(key, defMd5, payload, configMd5, generation, defContent, Optional.empty());
+        RawConfig config2 = new RawConfig(key, defMd5, payload, configMd5, 2L, defContent, Optional.empty());
+        assertThat(config, is(not(config2)));
+        assertThat(config.hashCode(), is(not(config2.hashCode())));
+
+        // different config md5 and with vespa version
+        final VespaVersion vespaVersion = VespaVersion.fromString("5.37.38");
+        RawConfig config3 = new RawConfig(key, defMd5, payload, "9999", generation, defContent, Optional.of(vespaVersion));
+        assertThat(config, is(not(config3)));
+        assertThat(config.hashCode(), is(not(config3.hashCode())));
+        // Check that vespa version is set correctly
+        assertThat(config3.getVespaVersion().get().toString(), is(vespaVersion.toString()));
+        assertThat(config.getVespaVersion(), is(not(config3.getVespaVersion())));
+
+        // null config
+        assertFalse(config.equals(null));
+
+        // different type of object
+        assertFalse(config.equals(key));
+
+        // errors
+        RawConfig errorConfig1 = new RawConfig(key, defMd5, payload, configMd5, generation, 1, defContent, Optional.empty());
+        assertThat(errorConfig1, is(errorConfig1));
+        assertThat(config, is(not(errorConfig1)));
+        assertThat(config.hashCode(), is(not(errorConfig1.hashCode())));
+        assertThat(errorConfig1, is(errorConfig1));
+        RawConfig errorConfig2 = new RawConfig(key, defMd5, payload, configMd5, generation, 2, defContent, Optional.empty());
+        assertThat(errorConfig1, is(not(errorConfig2)));
+        assertThat(errorConfig1.hashCode(), is(not(errorConfig2.hashCode())));
+    }
+
+    @Test
+    public void payload() {
+        RawConfig config = new RawConfig(key, defMd5, payload, configMd5, generation, defContent, Optional.empty());
+        assertThat(config.getPayload(), is(payload));
+        assertThat(config.getConfigMd5(), is(configMd5));
+        assertThat(config.getGeneration(), is(generation));
+        assertThat(config.getDefContent(), is(defContent));
+    }
+
+    @Test
+    public void require_correct_defmd5() {
+        final String defMd5ForEmptyDefContent = "d41d8cd98f00b204e9800998ecf8427e";
+
+        RawConfig config = new RawConfig(key, null, payload, configMd5, generation, defContent, Optional.empty());
+        assertThat(config.getDefMd5(), is(defMd5));
+        config = new RawConfig(key, "", payload, configMd5, generation, defContent, Optional.empty());
+        assertThat(config.getDefMd5(), is(defMd5));
+        config = new RawConfig(key, defMd5, payload, configMd5, generation, defContent, Optional.empty());
+        assertThat(config.getDefMd5(), is(defMd5));
+        config = new RawConfig(key, null, payload, configMd5, generation, null, Optional.empty());
+        assertNull(config.getDefMd5());
+        config = new RawConfig(key, null, payload, configMd5, generation, Arrays.asList(""), Optional.empty());
+        assertThat(config.getDefMd5(), is(defMd5ForEmptyDefContent));
+        config = new RawConfig(key, "", payload, configMd5, generation, null, Optional.empty());
+        assertThat(config.getDefMd5(), is(""));
+        config = new RawConfig(key, "", payload, configMd5, generation, Arrays.asList(""), Optional.empty());
+        assertThat(config.getDefMd5(), is(defMd5ForEmptyDefContent));
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/RequestValidationTest.java b/config/src/test/java/com/yahoo/vespa/config/RequestValidationTest.java
new file mode 100644
index 00000000000..1e237145b02
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/RequestValidationTest.java
@@ -0,0 +1,35 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.vespa.config.protocol.RequestValidation;
+import org.junit.Test;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+public class RequestValidationTest {
+
+    @Test
+    public void testVerifyName() {
+        assertTrue(RequestValidation.verifyName("foo"));
+        assertTrue(RequestValidation.verifyName("Foo"));
+        assertTrue(RequestValidation.verifyName("foo-bar"));
+        assertFalse(RequestValidation.verifyName("1foo"));
+        assertTrue(RequestValidation.verifyName("foo_bar"));
+    }
+
+    @Test
+    public void testVerifyDefMd5() {
+        assertTrue(RequestValidation.verifyMd5(""));
+        assertTrue(RequestValidation.verifyMd5("e8f0c01c7c3dcb8d3f62d7ff777fce6b"));
+        assertTrue(RequestValidation.verifyMd5("e8f0c01c7c3dcb8d3f62d7ff777fce6B"));
+        assertFalse(RequestValidation.verifyMd5("aaaaaaaaaaaaaaaaaa"));
+        assertFalse(RequestValidation.verifyMd5("-8f0c01c7c3dcb8d3f62d7ff777fce6b"));
+    }
+
+    @Test
+    public void testVerifyTimeout() {
+        assertTrue(RequestValidation.verifyTimeout(1000L));
+        assertFalse(RequestValidation.verifyTimeout(-1000L));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/SlimeUtilsTest.java b/config/src/test/java/com/yahoo/vespa/config/SlimeUtilsTest.java
new file mode 100644
index 00000000000..742fed77c36
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/SlimeUtilsTest.java
@@ -0,0 +1,82 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.slime.Cursor;
+import com.yahoo.slime.Slime;
+import com.yahoo.text.Utf8;
+import org.junit.Test;
+
+import java.io.IOException;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author lulf
+ * @since 5.8
+ */
+public class SlimeUtilsTest {
+    @Test
+    public void test_copying_slime_types_into_cursor() {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("foo", "foobie");
+        Cursor subobj = root.setObject("bar");
+
+        Slime slime2 = new Slime();
+        Cursor root2 = slime2.setObject();
+        root2.setString("a", "a");
+        root2.setLong("b", 2);
+        root2.setBool("c", true);
+        root2.setDouble("d", 3.14);
+        root2.setData("e", new byte[]{0x64});
+        root2.setNix("f");
+
+        SlimeUtils.copyObject(slime2.get(), subobj);
+
+        assertThat(root.toString(), is("{\"foo\":\"foobie\",\"bar\":{\"a\":\"a\",\"b\":2,\"c\":true,\"d\":3.14,\"e\":\"0x64\",\"f\":null}}"));
+    }
+
+    @Test
+    public void test_copying_slime_arrays_into_cursor() {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("foo", "foobie");
+        Cursor subobj = root.setObject("bar");
+
+        Slime slime2 = new Slime();
+        Cursor root2 = slime2.setObject();
+        Cursor array = root2.setArray("a");
+        array.addString("foo");
+        array.addLong(4);
+        array.addBool(true);
+        array.addDouble(3.14);
+        array.addNix();
+        array.addData(new byte[]{0x64});
+        Cursor objinner = array.addObject();
+        objinner.setString("inner", "binner");
+
+        SlimeUtils.copyObject(slime2.get(), subobj);
+
+        assertThat(root.toString(), is("{\"foo\":\"foobie\",\"bar\":{\"a\":[\"foo\",4,true,3.14,null,\"0x64\",{\"inner\":\"binner\"}]}}"));
+    }
+
+    @Test
+    public void test_slime_to_json() throws IOException {
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("foo", "foobie");
+        root.setObject("bar");
+        String json = Utf8.toString(SlimeUtils.toJsonBytes(slime));
+        assertThat(json, is("{\"foo\":\"foobie\",\"bar\":{}}"));
+    }
+
+    @Test
+    public void test_json_to_slime() {
+        byte[] json = Utf8.toBytes("{\"foo\":\"foobie\",\"bar\":{}}");
+        Slime slime = SlimeUtils.jsonToSlime(json);
+        assertThat(slime.get().field("foo").asString(), is("foobie"));
+        assertTrue(slime.get().field("bar").valid());
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/SourceTest.java b/config/src/test/java/com/yahoo/vespa/config/SourceTest.java
new file mode 100644
index 00000000000..989131c8256
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/SourceTest.java
@@ -0,0 +1,166 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import com.yahoo.config.ConfigurationRuntimeException;
+import com.yahoo.foo.SimpletypesConfig;
+import com.yahoo.vespa.config.protocol.CompressionType;
+import com.yahoo.vespa.config.protocol.DefContent;
+import com.yahoo.vespa.config.protocol.JRTClientConfigRequest;
+import com.yahoo.vespa.config.protocol.JRTClientConfigRequestV3;
+import com.yahoo.vespa.config.protocol.Payload;
+import com.yahoo.vespa.config.protocol.Trace;
+import org.junit.Test;
+
+import java.util.Arrays;
+import java.util.List;
+import java.util.Optional;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.*;
+
+/**
+ * @author lulf
+ * @since 5.1
+ */
+public class SourceTest {
+
+    @Test
+    public void testSourceInterface() {
+        MockSourceConfig config = new MockSourceConfig(new ConfigKey<>(SimpletypesConfig.class, "foobio"));
+        assertThat(config.getKey().getConfigId(), is("foobio"));
+        config.setConfig(JRTClientConfigRequestV3.createWithParams(config.getKey(), DefContent.fromList(config.getDefContent()), "host", config.getDefMd5(), config.getGeneration(), 1000, Trace.createNew(), CompressionType.LZ4, Optional.empty()));
+        MockSource src = new MockSource(config);
+        assertThat(src.getState(), is(Source.State.NEW));
+        src.open();
+        assertTrue(src.opened);
+        assertTrue(src.getconfigged);
+        assertThat(src.getState(), is(Source.State.OPEN_PENDING));
+        src.open();
+        assertThat(src.getState(), is(Source.State.OPEN_PENDING));
+        src.getconfigged = false;
+        src.getConfig();
+        assertTrue(src.getconfigged);
+        assertThat(src.getState(), is(Source.State.OPEN_PENDING));
+        assertTrue(config.setConfigCalled);
+        assertTrue(src.openTimestamp > 0);
+        config.notifyInitMonitor();
+        config.setGeneration(4);
+        src.cancel();
+        assertTrue(src.canceled);
+        assertThat(src.getState(), is(Source.State.CANCEL_REQUESTED));
+        src.setState(Source.State.CANCELLED);
+        try {
+            src.open();
+            fail("Expected exception");
+        } catch (ConfigurationRuntimeException e) {
+        }
+        src.getconfigged = false;
+        src.getConfig();
+        assertFalse(src.getconfigged);
+        src.canceled = false;
+        src.cancel();
+        assertFalse(src.canceled);
+    }
+
+    public static class MockSource extends Source {
+        boolean opened, getconfigged, canceled = false;
+
+        public MockSource(SourceConfig sourceConfig) {
+            super(sourceConfig);
+        }
+
+        @Override
+        public void myOpen() {
+            opened = true;
+        }
+
+        @Override
+        protected void myGetConfig() {
+            getconfigged = true;
+        }
+
+        @Override
+        public void myCancel() {
+            canceled = true;
+        }
+    }
+
+    private static class MockSourceConfig implements SourceConfig {
+
+        boolean notifyCalled = false;
+        ConfigKey<?> key = null;
+        boolean setConfigCalled = false;
+        long generation = -1;
+        Payload payload;
+
+        public MockSourceConfig(ConfigKey<?> key) {
+            this.key = key;
+        }
+
+        @Override
+        public void notifyInitMonitor() {
+            notifyCalled = true;
+        }
+
+        @Override
+        public void setConfig(com.yahoo.vespa.config.protocol.JRTClientConfigRequest req) {
+            key = req.getConfigKey();
+            setConfigCalled = true;
+        }
+
+        @Override
+        public void setGeneration(long generation) {
+            this.generation = generation;
+        }
+
+        @Override
+        public String getDefName() {
+            return key.getName();
+        }
+
+        @Override
+        public String getDefNamespace() {
+            return key.getNamespace();
+        }
+
+        @Override
+        public String getDefVersion() {
+            return "";
+        }
+
+        @Override
+        public List<String> getDefContent() {
+            return Arrays.asList("foo");
+        }
+
+        @Override
+        public String getDefMd5() {
+            return key.getMd5();
+        }
+
+        @Override
+        public String getConfigId() {
+            return key.getConfigId();
+        }
+
+        @Override
+        public ConfigKey<?> getKey() {
+            return key;
+        }
+
+        @Override
+        public String getConfigMd5() {
+            return "bar";
+        }
+
+        @Override
+        public long getGeneration() {
+            return 0;
+        }
+
+        @Override
+        public RawConfig getConfig() {
+            return  new RawConfig(getKey(), getDefMd5(), payload, getConfigMd5(), generation, getDefContent(), Optional.empty());
+        }
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/TimingValuesTest.java b/config/src/test/java/com/yahoo/vespa/config/TimingValuesTest.java
new file mode 100644
index 00000000000..1bae6c79ccb
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/TimingValuesTest.java
@@ -0,0 +1,24 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config;
+
+import org.junit.Test;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.not;
+import static org.junit.Assert.assertThat;
+
+/**
+ * Note: Most of the functionality is tested implicitly by other tests
+ *
+ * @author <a href="mailto:musum@yahoo-inc.com">Harald Musum</a>
+ */
+public class TimingValuesTest {
+    @Test
+    public void basic() {
+        TimingValues tv = new TimingValues();
+        TimingValues tv2 = new TimingValues(1L, 1L, 1L, 1L, 1L, 1L, 1L, 1);
+        assertThat(tv.getRandom(), is(not(tv2.getRandom())));
+        TimingValues copy = new TimingValues(tv2);
+        assertThat(copy.toString(), is(tv2.toString()));  // No equals method, just using toString to compare
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/buildergen/ConfigBuilderGeneratorTest.java b/config/src/test/java/com/yahoo/vespa/config/buildergen/ConfigBuilderGeneratorTest.java
new file mode 100644
index 00000000000..3d24372c40c
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/buildergen/ConfigBuilderGeneratorTest.java
@@ -0,0 +1,51 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.buildergen;
+
+import com.google.common.io.Files;
+import com.yahoo.config.ConfigInstance;
+import com.yahoo.config.codegen.ConfigGenerator;
+import com.yahoo.slime.Cursor;
+import com.yahoo.slime.Slime;
+import com.yahoo.vespa.config.ConfigDefinitionKey;
+import com.yahoo.vespa.config.ConfigPayload;
+import com.yahoo.vespa.config.ConfigPayloadApplier;
+import org.junit.Test;
+
+import java.io.File;
+import java.io.IOException;
+import java.lang.reflect.InvocationTargetException;
+import java.net.URISyntaxException;
+
+import static junit.framework.TestCase.assertNotNull;
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author lulf
+ * @since 5.1
+ */
+public class ConfigBuilderGeneratorTest {
+    @Test
+    public void require_that_custom_classes_can_be_generated() throws URISyntaxException, IOException, ClassNotFoundException, IllegalAccessException, InstantiationException, NoSuchMethodException, InvocationTargetException {
+        String[] schema = new String[] {
+                "namespace=foo.bar",
+                "intval int",
+                "stringval string"
+        };
+        File tempDir = Files.createTempDir();
+        ConfigDefinitionKey key = new ConfigDefinitionKey("quux", "foo.bar");
+        ConfigCompiler compiler = new LazyConfigCompiler(tempDir);
+        ConfigInstance.Builder builder = compiler.compile(new ConfigDefinition(key.getName(), schema).generateClass()).newInstance();
+        assertNotNull(builder);
+        ConfigPayloadApplier<?> payloadApplier = new ConfigPayloadApplier<>(builder);
+        Slime slime = new Slime();
+        Cursor root = slime.setObject();
+        root.setString("intval", "3");
+        root.setString("stringval", "Hello, world");
+        payloadApplier.applyPayload(new ConfigPayload(slime));
+        String className = ConfigGenerator.createClassName(key.getName());
+        ConfigInstance instance = (ConfigInstance) builder.getClass().getClassLoader().loadClass("com.yahoo." + key.getNamespace() + "." + className).getConstructor(new Class<?>[]{builder.getClass()}).newInstance(builder);
+        assertNotNull(instance);
+        assertThat(instance.toString(), is("intval 3\nstringval \"Hello, world\""));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/classes/app.1.def b/config/src/test/java/com/yahoo/vespa/config/classes/app.1.def
new file mode 100644
index 00000000000..63e986b58ab
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/classes/app.1.def
@@ -0,0 +1,8 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+version=1
+
+message string default="Hello!"
+
+times int default=1
+
+a[].name string
diff --git a/config/src/test/java/com/yahoo/vespa/config/classes/qr-logging.def b/config/src/test/java/com/yahoo/vespa/config/classes/qr-logging.def
new file mode 100644
index 00000000000..57ad0050a26
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/classes/qr-logging.def
@@ -0,0 +1,34 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+version=3
+logger string default="com.yahoo"
+# Either QueryAccessLog for a regular Vespa access log, or YApacheAccessLog for a log on yApache format
+speciallog[].name string
+
+# Leave as ""
+speciallog[].type string
+
+speciallog[].filehandler.name string default=""
+
+# File name patterns supporting the expected time variables
+speciallog[].filehandler.pattern string default=".%Y%m%d%H%M%S"
+
+speciallog[].filehandler.rotation string default="0 60 ..."
+
+# Defines how file rotation is done. There are two options:
+#
+# "date" :
+# The active log file is given the name resulting from pattern (but in this case "pattern" must yield a
+# time-dependent name. In addition, a symlink is created pointing to the newest file.
+# The symlink is given the name of the symlink parameter (or the name of this service
+# if no parameter is given.
+#
+# "sequence" :
+# The active log file is given the name
+# defined by "pattern" (which in this case will likely just be a constant string).
+# At rotation, this file is given the name pattern.N where N is 1 + the largest integer found by
+# extracting the integers from all files ending by .Integer in the same directory
+#
+speciallog[].filehandler.rotatescheme string default="date"
+
+speciallog[].cachehandler.name string default=""
+speciallog[].cachehandler.size int default=1000
diff --git a/config/src/test/java/com/yahoo/vespa/config/classes/qr-templates.3.def b/config/src/test/java/com/yahoo/vespa/config/classes/qr-templates.3.def
new file mode 100644
index 00000000000..8483bf03c44
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/classes/qr-templates.3.def
@@ -0,0 +1,142 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+version=3
+
+## Directory for temporary files
+directory string default="tmp/templates"
+
+hey[].ho[].lets[].go string default="ramones"
+hey[].ho[].lets[].fishing int default=-4 range=[-8,0]
+hey[].ho[].lets[].gone int default=200 range=[0,1000000]
+hey[].ho[].lets[].ref reference
+hey[].ho[].gone int default=2000 range=[-10,2000000]
+hey[].ho[].going bool default=false
+hey[].ho[].wash double default=345.3
+hey[].ho[].me double default=-45.5 range=[-234.43,0]
+hey[].ho[].now double default=-34 range=[-234,0]
+hi[].there[].e enum { BATCH, REALTIME, INCREMENTAL} default=BATCH
+hi[].ther[].f enum { BATCH, REALTIME } default=BATCH
+
+#hey[] int
+mode enum { BATCH, REALTIME, INCREMENTAL} default=BATCH
+bar.arrline[] string
+az[] double
+bar.arline[] int range=[0,999]
+#bar[].version int
+b1[].b2[].b3[].b4[] bool
+## Capacities for all storage nodes
+capacity[] double range=[0,100]
+
+longVal long
+longWithDefault long default=9876543210
+longWithRange long range=[-9000000000,0]
+longArr[] long
+longArrWithRange[] long range=[0,9000000000]
+
+fileVal file
+fileWithDefault file
+fileArr[] file
+
+washing double default=5 range=[-1.4,34.324432]
+washer double default=46 range=[-1.6,54]
+
+urlprefix string
+
+## Prefix to use in queries to choose a given template
+templateset[].urlprefix string
+
+## The MIME type of a given template
+templateset[].mimetype string default="text/html"
+
+## The character set of a given template
+templateset[].encoding string default="iso-8859-1"
+
+## Not used
+templateset[].rankprofile int default=0
+
+
+## Not used in 1.0
+templateset[].keepalive bool default=false
+
+## Header template. Always rendered.
+templateset[].headertemplate string
+
+## Footer template. Always rendered.
+templateset[].footertemplate string
+
+## Nohits template. Rendered if there are no hits in the result.
+templateset[].nohitstemplate string
+
+## Hit template. Rendered if there are hits in the result.
+templateset[].hittemplate string
+
+## Error template. Rendered if there is an error condition. This is
+## not mutually exclusive with the (no)hit templates as such.
+templateset[].errortemplate string
+
+groupsheadertemplate string default="[DEFAULT]"
+
+## Aggregated groups header template.
+## Default rendering is used if missing
+templateset[].groupsheadertemplate string default="[DEFAULT]"
+
+## Aggregated range group template.
+## Default rendering is used if missing
+templateset[].rangegrouptemplate string default="[DEFAULT]"
+
+## Aggregated exact group template
+## Default rendering is used if missing
+templateset[].exactgrouptemplate string default="[DEFAULT]"
+
+## Aggregated groups footer template.
+## Default rendering is used if missing
+templateset[].groupsfootertemplate string default="[DEFAULT]"
+
+## Tags used to highlight results, starting a bolded section.
+## An empty string means the template should no override what
+## was inserted by the search chain.
+templateset[].highlightstarttag  string default=""
+## Tags used to highlight results, ending a bolded section
+## An empty string means the template should no override what
+## was inserted by the search chain.
+templateset[].highlightendtag  string default=""
+## Tags used to highlight results, separating dynamic snippets
+## An empty string means the template should no override what
+## was inserted by the search chain.
+templateset[].highlightseptag  string default=""
+
+## The summary class to use for this template if there is none
+## defined in the query.
+ilscript[].name         string
+ilscript[].doctype      string
+ilscript[].content[]    string
+config[].id reference
+config[].autostart string default="no"
+musum string
+
+auran string
+
+route[].name string
+route[].selector string
+route[].feed string
+
+languages[] string
+languages2[] string
+foolang[].lang[] string
+
+# Maps
+myIntMap{} int
+myStringMap{} string
+myStructMap{}.myInt int
+myStructMap{}.myString string
+myStructMap{}.myIntDef int default=56
+myStructMap{}.myStringDef string default="g"
+
+myStructMap{}.myNestedLeafMap{} long
+myStructMap{}.myNestedArray[] long
+
+myStructMap{}.myNestedMap{}.myLong long
+myStructMap{}.myNestedMap{}.myLongDef long default=-100
+
+myStructMap{}.myStruct.a string
+myStructMap{}.myStruct.b string default="pizza"
+myStructMap{}.myStruct.c file
diff --git a/config/src/test/java/com/yahoo/vespa/config/classes/ranges.1.def b/config/src/test/java/com/yahoo/vespa/config/classes/ranges.1.def
new file mode 100644
index 00000000000..bd054750db5
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/classes/ranges.1.def
@@ -0,0 +1,5 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+version=1
+quux int default=5 range=[,]
+xyzzy double default=5 range=[,]
+longVal long default=5 range=[,]
diff --git a/config/src/test/java/com/yahoo/vespa/config/classes/testfoobar.12.def b/config/src/test/java/com/yahoo/vespa/config/classes/testfoobar.12.def
new file mode 100644
index 00000000000..11ac4e0b247
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/classes/testfoobar.12.def
@@ -0,0 +1,925 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+version=12-1-2
+
+longVal long
+longWithDefault long default=8589934592
+
+fileVal file
+fileWithDefault file
+
+vh[] double range=[-300,300]
+bg[] int default=0 range=[-10,10]
+gee[] string
+storage[].feeder[] string
+storage[].distributor[] string
+
+ju[].hu[].tu[] double default=-45 range=[0,1000.1]
+ju[].hu[].wu[] enum { HEY, HO} default=HO
+ju[].hu[].tang[] bool default=false
+ju[].hu[].clan[] int default=45 range=[-90,90]
+ju[].hu[].sann reference
+
+foo string
+headertemplate string
+## If true, the bitvector part of results with number of hits within
+## max bin size will be merged into array form before applying static
+## rank. NB: Setting this to true may reduce performance.
+applystaticranktosmallbitvectors                 bool default=true
+
+## Size of bitvector cache (in bytes).
+bitvectorcachesize                                int default=50000000
+
+## Size of boolean occurrence cache (in bytes).
+boolocccachesize                                  int default=100000000
+
+## Size of dictionary cache (in bytes).
+dictcachesize                                     int default=40000000
+
+onedimstruct[].val string
+
+## Size of document info cache (in bytes).
+documentinfocachesize                             int default=25000000
+
+## Size of filter occurrence cache (in bytes).
+## This cache is used to optimizse exclusion handling.
+## A too small size limit will cause serious performance degradation
+## if the staticfilterindexes keyword is used.
+filterocccachesize                                int default=30000000
+
+## Size of integer range bitvector cache (in bytes).
+intrangebitvectorcachesize                        int default=50000000
+
+## Size of integer occurrence cache (in bytes).
+intocccachesize                                   int default=100000000
+
+## Size of phrase occurrence cache (in bytes).
+phrasecachesize                                   int default=150000000
+
+## Size of phrase occurrence index cache (in bytes).
+phraseidxcachesize                                int default=20000000
+
+## Size of position occurrence cache (in bytes).
+posocccachesize                                   int default=100000000
+
+## The filename of a file specifying which hosts that should have
+## access to the internal web-server of the fsearch process.
+accesslist                                        string default=""
+
+## The filename of the log file for HTTP access.
+accesslog                                         string default=""
+
+## The number of threads to perform async occurrence fetch, i.e.
+## read from posocc and boolocc files and possibly generation of
+## posocc/boolocc arrays for phrases. Async occurrence fetches
+## will use more system CPU but can reduce latency on lightly
+## loaded systems.
+asyncfetchocc                                     int default=0
+
+## specifies the high limit of the ranked result bin.
+## If the percentage of the resultset specified in binsize is higher
+## than this limit, this will be the max size.
+binhigh                                           int default=2147483647
+
+## specifies the lowest possible size of a ranked result. This is
+## the lower ramp of the percentage specified in the binsize variable.
+binlow                                            int default=10000
+
+## specifies the size of the ranked results as a percentage of the
+## total result set size. The percentage can be ramped off with the
+## binlow and binhigh variables. NB: Setting this to 100.0 may lead to
+## seriously reduced performance.
+binsize                                           double default=100.0
+
+## Check cache lines beyond offset + maxhits for blacklisting
+## in order to provide correct "totalhits" for queries with many hits.
+checktrailingcachelines				bool default=false
+
+## specifies the number of result entries that are processed when
+## doing site collapsing. Site collapsing is performed by reordering
+## the first collapseentries hits in the result set, listing
+## the best hit from each site first.
+collapseentries                                   int default=200 range=[0,1000000]
+
+## Specifies what is the default field used for collapse
+defaultcollapse                                   string default=""
+
+## specifies the rank penalty for additional hits from a site found
+## during site collapsing. When additional hits from a site are
+## found, the rank values of those hits are reduced by shifting
+## them collapserankshift places to the right.
+collapserankshift                                 int default=0
+
+## The maximum number of active and queued requests. Exceeding
+## requests will be discarded.
+cutofftransportconns                              int default=1024
+
+## specifies the directory where the dataset resides. Only the
+## directory needs to be specified. fsearch will then read the config
+## files (index.cf) in that directory to discover the structure.
+datasetdir                                        string default=""
+
+## If set to "yes", then fallback to the default index if a query
+## term specifies a non-existing index. If set to "no", then always
+## return 0 hits for a query term that specifies a non-existing index.
+## Note that the result set for the entire query might still contain
+## hits from other query terms unless the invalid query term was an
+## and-term. Default value is "no".
+defaultindexfallback                              string default="no"
+
+# ???
+docattrhashsize                                   int default=8171
+# ???
+docidhashsize                                     int default=8171
+# ???
+docport                                           int default=0
+
+## If present, the result cache is not flushed due to reload operation
+## unless the document summaries have changed.
+dontflushresultcacheonreload                      bool default=false
+
+## Colon-delimeted list of catalogs for which negative dictionary
+## entries should not be cached. Default is unset. Most useful for
+## dictionary files that are memorymaped or memorylocked in
+## indextune.cf. Note that the list must start and end with a colon (:).
+dropnegativedictionarycacheentriescatalogs        string default=""
+
+## specifies a term (used in an ANDNOT) to be used for filtering ALL queries.
+excludefilter                                     string default=""
+
+## If set to "yes", use of firstoccproximity is enabled. If set to
+## "no", use of firstoccproximity is disabled.
+firstoccproximity                                 string default=""
+
+## If present, the filter occurrence cache is flushed due to reload
+## operation when all queries using the old configuration has completed.
+flushfilteroccscacheonreload                      bool default=false
+
+## Do not use position occurrence information, even though it might
+## be present in the index.
+forceemptyposoccs                                 bool default=false
+
+## The port to run Fnet Remote Tools (RPC) service on.
+## If set to 0, no FRT service is provided.
+frtport                                           int default=0
+
+## The directory where gid based blacklist files are found.
+## Used for "realtime" indexing setups.
+gidblacklistdir				  string default="../gidblacklist"
+
+## A semicolon-separated list of index names and index name prefixes
+## defining the set of indexes that are relevant when highlighting
+## query keywords. The terms and phrases from the query targeting any
+## of these indexes will be highlighted when dynamic teasers are
+## generated. In order to separate index names and index name prefixes
+## in the list, index name prefixes have a trailing '*'. Note that
+## index aliases are treated like actual index names. This means that
+## if you have an index relevant for highlighting and an index alias
+## pointing to that index, you need to configure both as relevant for
+## highlighting if you want to highlight keywords targeting both the
+## actual index and the alias. Example config value: "normal*;title".
+## Default config value: "*" (highlight all keywords).
+highlightindexes                                  string default="*"
+
+# ???
+hostname                                          string default=""
+
+## provide a HTTP server at the given port number.
+hport                                             int default=8002
+
+## If true, the TCP_NODELAY option is set on the http connections.
+## This causes non-full packets to be sent even though previously sent
+## data hasn't yet been acknowledged (e.g. due to the delayed ack
+## feature present on various tcp stacks).
+httpdnodelay                                      bool default=false
+
+# ???
+intoccpoolsize                                    int default=32768
+# ???
+intoccpoolstep                                    int default=32768
+# ???
+jobqueuethreads                                   int default=5
+
+## Juniper configuration property map.
+## currently known keys with defaults:
+## [juniper.dynsum.highlight_on]        = "<b>"
+## [juniper.dynsum.highlight_off]       = "</b>"
+## [juniper.dynsum.continuation]        =  "..."
+## [juniper.dynsum.length]              =  "256"
+## [juniper.dynsum.min_length]          =  "128"
+## [juniper.stem.min_length]            =  "5"
+## [juniper.stem.max_extend]            =  "3"
+## [juniper.dynsum.surround_max]        =  "128"
+## [juniper.dynsum.max_matches]         =  "3"
+## [juniper.dynsum.escape_markup]       =  "auto"
+## [juniper.matcher.winsize]            = "200"
+## [juniper.dynsum.separators]          = "\0x1F\0x1D"
+## [juniper.dynsum.connectors]          = "\0x1F\0x1D"
+## [juniper.proximity.factor]           = "0.25"
+## [juniper.debug_mask]                 = "0"
+##
+#junipersetup                                      properties
+
+## The maximum number of HTTP connections.
+maxhttpconns                                      int default=1024
+
+## The maximum interval between a successful read from a socket
+## before timeout, in seconds.
+maxsocksilent                                     double default=5.0
+
+## The maximum number of threads to use.
+maxthreads                                        int default=100
+
+## The maximum number of active requests at any time. Exceeding
+## requests will be queued.
+maxtransportconns                                 int default=15
+
+## If present the index to the document summary file (docsum.idx)
+## is accessed on disk on each access instead of being cached in
+## memory. For experimental use on systems with very many docu-
+## ments but very few actual docsum requests.
+nodocsumidxinmemory                               bool default=false
+
+## If set then locks on result cache are held only for very
+## short intervals and only a single cache element is locked at a
+## time. This simplifies the mutex locking order, but cause extra
+## load due to queries that would previously first block then use
+## cached value now being fully evaluted.
+nonblockingresultcache                            bool default=false
+
+## A boolean value controlling removal of several common accented
+## uses of characters, used when matching for highlighting.
+normalize.accentremoval                           bool default=true
+
+## A boolean value controlling normalizing of LATIN CAPITAL/SMALL
+## LIGATURE OE (U+0152 U+0153) to the string "oe", used when matching
+## for highlighting.
+normalize.ligaturesubstitution                    bool default=true
+
+## A boolean value controlling normalizing of various accented letters
+## to two chars, for linguistics compatibility.
+normalize.multicharexpansion                      bool default=true
+
+## A boolean value controlling normalizing of LATIN SMALL LETTER SHARP S
+## (U+00DF) to the string "ss", used when matching for highlighting.
+normalize.sharpssubstitution                      bool default=true
+
+## If true, queries are still handled during the reload operation
+## (even when the document summaries have changed). If false then
+## queries are stalled until reload has completed.
+overlappedreload                                  bool default=true
+
+## The partition number to report to the connecting fdispatch process
+## if the dataset label didn't specify the partition number.
+partition                                         int default=0
+
+## If set to "yes", use of proximity (cf. proximity and firstoccproximity)
+## will affect phrases in addition to single words. If set to "no",
+## use of proximity is never used for phrases.
+phraseproximity                                   string default=""
+
+## The file name to write the PID of the fsearch process to.
+pidfile                                           string default=""
+
+## Minimum value for maximum value of number of 'posocc' entries
+## for a word. If set to 0, computed as 2 * binlow.
+posbinhigh                                        int default=0
+
+## Maximum value for maximum value of number of 'posocc' entries
+## for a word. If set to 0, computed as min(4 * binhigh, 0x7fffffff)
+posbinlow                                         int default=0
+
+## The maximum value for number of 'posocc' entries for a word,
+## specified as a percentage of the number of documents in the index.
+## If more entries are needed for evaluation, posocc entries are not
+## used for that word and evaluation will be performed without full
+## proximity support. The percentage can be ramped off with the posbinlow
+## and posbinhigh variables. If set to 0, computed as 2.0 * binsize.
+posbinsize                                        double default=0
+
+## If set to "yes", use of posocc files is enabled, except when
+## "forceemptyposoccs" is set or posocc files doesn't exist. If
+## set to "no", use of posocc files is disabled.
+proximity                                         string default=""
+
+## Selects behavior when proximity can be used for two words but
+## not three words while firstoccproximity can be used for three
+## words. If set to "yes", then use proximity for two words. If
+## set to "no", then use firstoccproximity for three words.
+proximitypairbeforefirstoccproximitytriple        string default=""
+
+## Selects behavior when proximity can be used for three words but
+## not four words while firstoccproximity can be used for four
+## words. If set to "yes", then use proximity for three words. If
+## set to "no", then use firstoccproximity for four words. The
+## default is "yes".
+proximitytriplebeforefirstoccproximityquad        string default=""
+
+## specifies the port number for the persistent internal transport
+## protocol provided for a multi-level dispatch system.
+ptport                                            int default=8003
+
+## a reference to a rank-profiles.def type configuration
+## describing how to rank results.  If empty, fsearch loads
+## rank.cf from the dataset directory, see rank.cf(5).
+rankcf                                            reference
+
+## specifies a lower limit for the rankvalue of the results
+## returned from the search node.
+rankcutoff                                        int default=0
+
+## if set, an internal calculation is used for determining a
+## rank cutoff value as above.
+rankcutoffadvanced                                bool default=false
+
+## Specifies the constant value used in the internal advanced rank
+## cutoff calculations done when the rankcutoffadvanced parameter is set.
+## This roughly reflects the expected rank contribution of
+## one good term.
+rankcutoffadvval                                  int default=0
+
+# ???
+rankinginfopoolsize                               int default=1048576
+# ???
+rankinginfopoolstep                               int default=262144
+## Grace period (in seconds) after index reload where old index is
+## still available.
+reloadgraceperiod				  int default=64
+
+## Maximum number of entries in the resultattributescache.
+resultattributescachequeries                      int default=0
+## Maximum number of entries in the resultattributescache.
+## 0 means no limitation.
+resultattributescachesize                         int default=5000000
+
+## The maximum lifetime of a resultcache element in seconds.
+resultcachemaximumlifetime                        int default=7200
+## The minimum lifetime of a resultcache element in seconds.
+resultcacheminimumlifetime                        int default=3600
+
+## Maximum number of entries in the resultcache.
+## 0 means no limitation.
+resultcachequeries                                int default=0
+## Maximum size (in bytes) in the resultcache.
+resultcachesize                                   int default=50000000
+
+# ???
+rewriter.indexes                                  string default=""
+# ???
+rewriter.langfield                                string default="bsumlanguage"
+# ???
+rewriter.rootdir                                  string default=""
+# ???
+#rewritersetup                                     properties
+
+## Set the number of samples a disk is marked as slow before
+## starting selftest when no progress occurred during the last
+## slowdisksamples samples.
+slowdisklatch                                     int default=1
+
+## Set the number of milliseconds to sleep between each sample of
+## disk state.
+slowdisksamplemillisleep                          int default=100
+
+## Set the number of nanoseconds to sleep between each sample of
+## disk state. If 0, use slowdisksamplemillisleep instead.
+## Restriction: This option only has effect on FreeBSD
+## using the LinuxThreads port.
+slowdisksamplenanosleep                           int default=0
+
+## Set the number of contigous disk samples without progress and
+## outstanding requests before a disk is detected as slow.
+## If zero, automatic slowdisk detection is turned off.
+## Recommended value is '20' (when using default values for the
+## other slowdisk detection parameters).
+slowdisksamples                                   int default=0
+
+# ???
+staticfilter                                      string default=""
+
+## specifies a set of indexes for which to optimize exclusion
+## handling. Colon is used to separate index names. Default is unset.
+## The optimization use entries in the filter occurrence cache, thus
+## a too small size limit of the cache will cause serious performance
+## degradation.
+staticfilterindexes                               string default=""
+
+# ???
+strictbind                                        bool default=false
+
+## Specifies a file containing url coded queries to run as part of self
+## test initiated when a slow disk has been detected.
+testloadfile                                      string default=""
+
+## the type of transport to use.  Currently only "fnet" is available.
+transport                                         string default=""
+
+## Specifies the transport access log file used by the http server.
+## The real log file name is created by using the strftime function
+## with the given argument as template.
+transportaccesslog              string 	    default=""
+
+## Specifies the interval between transport access log rotation.
+## This is the number of minutes between log rotation, e.g a value
+## of 1440 indicates that the log should be rotated every 24 hour.
+transportaccesslogcycle         int    	    default=1440
+
+## Specifies the offset from the start of each cycle when the
+## transport access log should be cycled automatically. The unit
+## is seconds, e.g. a value of 1020 indicates that the log should
+## be cycled at 17 minutes past each cycle.
+transportaccesslogcycleoffset   int    	    default=0
+
+## Reference to VSM (Vespa Stream Matcher) configuration. If this is
+## set, fsearch will run in VSM mode.
+vsmconfig                                         reference
+
+## If true, the TCP_NODELAY option is set on the persistent transport
+## connections.  This causes non-full packets to be sent even though
+## previously sent data hasn't yet been acknowledged (e.g. due to the
+## delayed ack feature present on various tcp stacks).
+transportnodelay                                  bool default=true
+
+# ???
+wordfolder                                        bool default=false
+# ???
+wordhashsize                                      int default=524269
+# ???
+wordoccpoolsize                                   int default=2097152
+# ???
+wordoccpoolstep                                   int default=524288
+# ???
+wordpoolsize                                      int default=262144
+# ???
+wordpoolstep                                      int default=65536
+
+## Connect spec for transactionlog server.
+tlsspec string default=""
+
+## Document manager config
+documentmanagerconfigid reference
+
+functionmodules[]	string restart
+
+specialchars string
+
+tokenlist[].name     string
+tokenlist[].tokens[].token string
+tokenlist[].tokens[].replace string default=""
+
+afloat double default=34 range=[0,1002]
+
+## qr-searchers:
+tag.bold.open string default="<hi>"
+tag.bold.close string default="</hi>"
+tag.separator string default="<sep />"
+
+## This array contains the built-in searchers that should
+## normally always run in a Vespa-S system.  The actual list is
+## in the global/ directory on the configserver.
+builtin[].searcher string
+
+## If for some reason you need to disable one of the built-in
+## searchers you can set this flag to "false".  Handle with great
+## care.  You need to match the array index from the global/
+## directory, and this may change depending on versions.
+builtin[].enabled bool default=true
+
+# some searcher specific configuration parameters:
+
+com.yahoo.prelude.searcher.FieldCollapsingSearcher.collapsesize int default=1
+com.yahoo.prelude.searcher.FieldCollapsingSearcher.extrafactor double default=2.0
+com.yahoo.prelude.searcher.FieldCollapsingSearcher.collapsefield string default="mid"
+
+com.yahoo.prelude.searcher.BlendingSearcher.numthreads int default=200
+com.yahoo.prelude.searcher.BlendingSearcher.docid string default=""
+
+com.yahoo.prelude.searcher.BoldingSearcher.source string default=""
+
+com.yahoo.prelude.searcher.JuniperSearcher.source string default=""
+com.yahoo.prelude.searcher.JuniperSearcher.defaultdoctype string default=""
+
+## Query cache that can be placed anywhere in the search chain. Query/Result
+## pairs (ie. entries) bigger than maxentrysizebytes will not be cached.
+com.yahoo.prelude.searcher.CachingSearcher.cachesizemegabytes int default=100
+com.yahoo.prelude.searcher.CachingSearcher.timetoliveseconds int default=3600
+com.yahoo.prelude.searcher.CachingSearcher.maxentrysizebytes int default=10000
+
+com.yahoo.prelude.searcher.XMLStringSearcher.source string default=""
+
+## relevancy as measured from the backend will usually be
+## normalized into the [0,1000] range to make blending between
+## several backends with different relevancy models possible; you
+## can elect to skip this if you only have backends using
+## relevancy scores that are directly comparable.
+com.yahoo.prelude.fastsearch.FastSearcher.skipnormalizing bool default=true
+
+## how many aggregation groups to fetch from the backend
+com.yahoo.prelude.grouping.AggregatingSearcher.maxgroups int default=100
+
+com.yahoo.prelude.querytransform.PhrasingSearcher.automatonfile string default=""
+com.yahoo.prelude.querytransform.NonPhrasingSearcher.automatonfile string default=""
+com.yahoo.prelude.querytransform.TermReplacingSearcher.termlist[] string
+com.yahoo.prelude.querytransform.CompleteBoostSearcher.source string default=""
+
+com.yahoo.prelude.querytransform.ExactStringSearcher.source string default=""
+com.yahoo.prelude.querytransform.LiteralBoostSearcher.source string default=""
+com.yahoo.prelude.querytransform.TermBoostSearcher.source string default=""
+com.yahoo.prelude.querytransform.NormalizingSearcher.source string default=""
+com.yahoo.prelude.querytransform.StemmingSearcher.source string default=""
+
+com.yahoo.prelude.statistics.StatisticsSearcher.latencybucketsize int default=30
+
+
+# here users may add their custom searchers
+# (all strings should be class names)
+customizedsearchers.rawquery[] string
+customizedsearchers.transformedquery[] string
+customizedsearchers.blendedresult[] string
+customizedsearchers.unblendedresult[] string
+customizedsearchers.backend[] string
+customizedsearchers.argument[].key string
+customizedsearchers.argument[].value string
+
+## This is for adding searchers which should be below BlendingSearcher,
+## but not be linked to any Vespa cluster (directly).
+external[].name string
+external[].searcher[] string
+
+# Search cluster specific information.
+## Name of search cluster.
+searchcluster[].name string default=""
+
+## Names of search definitions served by search cluster.
+searchcluster[].searchdef[] string
+
+## configid that may be used to get rank-profiles config for the cluster.
+searchcluster[].rankprofiles.configid reference default=""
+
+## Indexing mode of search cluster.
+searchcluster[].indexingmode enum { REALTIME, STREAMING } default=REALTIME
+
+## Storage cluster to use for search cluster if indexingmode is streaming.
+searchcluster[].storagecluster string default=""
+
+# The available dispatchers on each search cluster
+searchcluster[].dispatcher[].host string
+searchcluster[].dispatcher[].port int
+
+## The number of least significant bits of the part id used to specify the
+## row number (the rest of the bits specifies the column). Don't touch
+## this unless you know why you are doing it.
+searchcluster[].rowbits int default=0
+
+
+# 4 search-cluster-specific overrides of global cache parameters:
+
+## Internal searcher cache. Size is measured in megabytes of raw packet
+## size. Hits larger than 1% of total cache size will not be cached.
+searchcluster[].cache.size int default=1
+
+## Timeout for internal searcher cache. Entries older than this number
+## of seconds will be removed from cache. 0 means no cache timeout.
+## If cachetimeoutseconds is used, the cache is not purged when reindexing.
+searchcluster[].cache.timeout int default=-1
+
+## If timeoutwithpurging is set, the index will be purged (possibly
+## gradually) when index switching occurs, even if cache timeout > 0.
+## Not used if cache timeout is 0. If searchcluster[].cache.timeout is
+## not explicitly set, the global value will be used instead of the one
+## set locally.
+searchcluster[].cache.timeoutwithpurging bool default=false
+
+## Gradual cache switching causes the index to only be gradually purged
+## when cache switching occurs. cacheswitchseconds is the length of the period
+## when a given cache entry may be from either the previous or current
+## index. Setting it to 0 makes QRS purges the cache entirely when a new
+## index becomes available. At the end of the cacheswitchseconds period,
+## the cache will be cleaned of any remaining entries from the previous
+## index.
+searchcluster[].cache.switchseconds int default=-1
+
+# Per dispatcher config-id might be nice to have, remove it until needed.
+# searchcluster[].dispatcher[].configid reference
+
+# rank-profiles
+## name of this rank profile. maps to table index for internal use.
+rankprofile[].name string
+
+## the name of a generic property available to the feature execution framework and feature plugins
+rankprofile[].fef.property[].name string
+
+## the value of a generic property available to feature plugins
+rankprofile[].fef.property[].value string
+
+## the catalog name overrides apply to
+rankprofile[].catalog[].name string
+
+## Boost value for AND queries in this catalog.
+rankprofile[].catalog[].andboost int default=0
+
+## Boost value for OR queries in this catalog.
+rankprofile[].catalog[].orboost int default=0
+
+## Boost value for ANY queries in this catalog.
+rankprofile[].catalog[].anyboost int default=0
+
+## Boost value for NEAR queries in catalog.
+rankprofile[].catalog[].nearboost int default=0
+
+## Boost value for ORDEREDNEAR queries in this catalog.
+rankprofile[].catalog[].orderednearboost int default=0
+
+## Boost value for phrase queries in this catalog.
+rankprofile[].catalog[].phraseboost int default=0
+
+## Boost value for all queries in catalog.
+rankprofile[].catalog[].rankboost int default=0
+
+## If true, the context boost is the max value of
+## the individual contextboosts.
+## When false, the context boost when a term is in
+## several contexts is the sum of the individual contextboosts.
+rankprofile[].catalog[].bestcontextboostonly bool default=false
+
+
+## If true, then use extnumoccboost only when calculating rank values.
+## Also, do not normalize the extnumoccboost value with
+## global term frequency. Default value is false.
+rankprofile[].catalog[].extnumoccboostonly bool default=false
+
+## If yes, then use extnumoccboost only when calculating rank values.
+## Also, do not normalize the extnumoccboost value with
+## global term frequency. Default value is no.
+rankprofile[].catalog[].numoccandextnumoccboostonly bool default=false
+
+## If yes, then use bitvectors when possible.
+## Default value is false.
+rankprofile[].catalog[].preferbitvector bool default=false
+
+## Load extnumoccboost for this catalog from the named file.
+## extnumoccboost specifies boost values due to the number of
+## occurences of a term that are external to the document. If
+## "NULL" is given as file name, then all extnumoccboost values
+## will be set to 0.
+rankprofile[].catalog[].extnumoccboost.table string default="/home/vespa/conf/vespa/search/ranktables/constant-0000"
+
+## Load numoccboost for this catalog from the named file.
+## numoccboost specifies boost values due to the number of occurences in
+## a document. If "NULL" is given as file name, then all numoccboost
+## values will be set to 0.
+rankprofile[].catalog[].numoccboost.table string default="/home/vespa/conf/vespa/search/ranktables/constant-0000"
+
+## Load firstoccboost for catalog from the file named.
+## firstoccboost specifies boost values due to the position of the
+## first occurence in a document. If "NULL" is given as file name,
+## then all firstoccboost values will be set to 0.
+rankprofile[].catalog[].firstoccboost.table string default="/home/vespa/conf/vespa/search/ranktables/constant-0000"
+
+
+## Load firstoccproximityboost for this catalog from the file named.
+## firstoccproximity boost specifies boost values due to the correlation between
+## positions of the first occurence in a document for two and two words.
+##
+## If "NULL" is given as file name, then all
+## firstoccproximityboost values will be set to 0. If otherwise set,
+## should be the name of a file to load into the table. The file
+## should have 256 lines each containing a single integer.
+##
+## There are 256 elements in the table, handling forward distances from 1.
+## The corresponding firstoccrevproximityboost table is used
+## to handle closeness in reverse order.
+##
+## The last array index specifies the proximity table set. During
+## evaluation, the bigram proximity weight supplied by the query segmenter
+## specifies which proximity table set to use, with a fallback to set 0
+## when no information is available.
+rankprofile[].catalog[].firstoccproximityboost[].table string default="/home/vespa/conf/vespa/search/ranktables/constant-0000"
+
+## Load firstoccrevproximityboost table for this catalog from the named file.
+## Specifies boost values due to the correlation between positions
+## of the first occurence in a document for two and two words when
+## the second word in the query comes first in the document.
+## See also firstoccproximityboost above.
+rankprofile[].catalog[].firstoccrevproximityboost[].table string default="/home/vespa/conf/vespa/search/ranktables/constant-0000"
+
+## Load proximityboost for this catalog from the named file.
+## proximity boost specifies boost values due to the correlation between
+## positions of the occurences in a document for two and two words.
+## See also firstoccproximityboost above.
+rankprofile[].catalog[].proximityboost[].table string default="/home/vespa/conf/vespa/search/ranktables/constant-0000"
+
+## Load revproximityboost for this catalog from the named file.
+## revproximity boost specifies boost values due to the correlation between
+## positions of the occurences in a document for two and two words.
+## See also firstoccproximityboost above.
+rankprofile[].catalog[].revproximityboost[].table string default="/home/vespa/conf/vespa/search/ranktables/constant-0000"
+
+## Load divtable for this catalog from the named file.
+## Rank values for a query term are divided by the entry
+## in divtable indexed by log2 of term frequence.
+## The file should contain ?? lines each with a single integer.
+rankprofile[].catalog[].divtable string default=""
+
+## The name of a context in this catalog to specify boosts for.
+rankprofile[].catalog[].context[].name string
+
+## Boost occurrences in this context with the given value.
+## XXX -1 uses default (???) from somewhere(TM).
+rankprofile[].catalog[].context[].contextboost int default=0
+
+## Boost pair of occurrences in this context with
+## the given value when evaluating 2 words from same catalog in
+## parallell.
+## XXX -1 uses default (???) from somewhere(TM).
+rankprofile[].catalog[].context[].commoncontextboost.pair int default=0
+
+## Boost triple of occurrences in this context with
+## the given value when evaluating 3 words from same catalog in
+## parallell.
+## XXX -1 uses default (???) from somewhere(TM).
+rankprofile[].catalog[].context[].commoncontextboost.triple int default=0
+
+## Boost quad of occurrences in this context with
+## the given value when evaluating 4 words from same catalog in
+## parallell.
+## XXX -1 uses default (???) from somewhere(TM).
+rankprofile[].catalog[].context[].commoncontextboost.quad int default=0
+
+
+## The name of the attribute
+rankprofile[].attribute[].name string
+
+## Boost value for queries that hit in this attribute
+rankprofile[].attribute[].attributecontextboost int default=0
+
+## Load weightboost for this attribute from the named file.
+## weightboost specifies boost values due to the weight (weighted set)
+## or number of occurences (single, array) in an attribute.
+## If "NULL" is given as file name, then all weightboost values will be set to 0.
+rankprofile[].attribute[].weightboost.table string default="/home/vespa/conf/vespa/search/ranktables/constant-0000"
+
+
+## Load static rank values from the given staticrank docattr vector.
+## Must be specified in index.cf as a staticrankfile.
+rankprofile[].staticrankfile string default=""
+
+## Multiply static rank values with given value when calculating total
+## rank value.
+rankprofile[].staticcoefficient int default=1
+
+## If false then use only static ranking when sorting result hits.
+## Default is true.
+rankprofile[].dynamicranking bool default=true
+
+## If dynamic ranking is turned off, then ascending will sort the
+## result hits with lowest static rank values first, while
+## descending will sort with highest static rank values
+## first. Default is descending. This keyword has no effect if
+## dynamic ranking is on.
+rankprofile[].staticranksortorder string default="descending"
+
+## Load static rank mapping from the file named table. The static
+## rank mapping maps each 8-bit static rank value into a 32-bit static
+## rank value. This option may only be used with 8-bit static rank files.
+rankprofile[].staticrankmap string default=""
+
+## If set to "true", total rank will be reduced when dynamic rank is less than
+## 25% of static rank, to suppress irrelevant hits from popular sites.
+## If set to "false", total rank is not reduced.
+rankprofile[].clampstaticrank bool default=false
+
+## Load document datetime values used for freshness boost calculation from
+## this file. The values must be coded as minutes since
+## 1900-01-01T00:00Z. The value 0 has the special meaning
+## "no datetime value exists".
+rankprofile[].freshnessboost.file string default=""
+
+## Load freshnessboost lookup-table values from the file named
+## table instead of using built-in default values. The file must
+## contain 32 white-space separated non-negative integers.
+rankprofile[].freshnessboost.table string default="/home/vespa/conf/vespa/search/ranktables/constant-0000"
+
+## When calculating the freshness boost value multiply difference between
+## current datetime and document datetime with timeoffset before taking
+## the base-2 logarithm. Default value is 1. Max value is 31.
+rankprofile[].freshnessboost.timeoffset int default=1
+
+## If a document has datetime value 0, then use defaultboostvalue
+## as freshness boost value instead of doing table lookup. The default
+## default value is 0 (no boost).
+rankprofile[].freshnessboost.defaultboostvalue int default=0
+
+## Multiply freshness boost value with coefficient when calculating
+## total freshness boost value. If coefficient 0 is used, no freshness
+## boost value will be computed or added. Default value is 0.
+rankprofile[].freshnessboost.coefficient int default=0
+
+## boost table files for distance ranking, 1 dimension.
+## The tables have 465 elements each, where slots 0..15 represents
+## distances 0..15 while the remaining slots represents distance
+## (16 + (slot & 15)) << ((slot >> 4) - 1).  Linear interpolation is
+## used for distances "between" table slots.
+##
+## If "NULL" is given as the file name then all 1D distance boost values
+## for that table will be set to 0.
+rankprofile[].distance1dboosttable[].table string
+
+## boost table files for distance ranking, 2 dimensions.
+## The tables have 977 elements each, where slots 0..15 represents
+## square of distance being 0..15 while the remaining slots represents
+## square of distance distance being
+## (16 + (slot & 15)) << ((slot >> 4) - 1). Linear interpolation is
+## used for distances "between" table slots.
+##
+## If "NULL" is given as the file name then all 2D distance boost values
+## for that table will be set to 0.
+rankprofile[].distance2dboosttable[].table string
+
+## The lowest possible size of a ranked result. This is the lower ramp
+## of the percentage specified in the binsize variable. The default is
+## specified in fsearchrc.
+rankprofile[].binlow int default=-1
+
+## The high limit of the ranked result bin. If the percentage of the
+## resultset specified in binsize is higher than this limit, this will be
+## the max size. The default is specified in fsearchrc.
+rankprofile[].binhigh int default=-1
+
+## The size of the ranked results as a percentage of the total result
+## set size. The percentage can be ramped off with the binlow and binhigh
+## variables. The default is specified in fsearchrc.
+rankprofile[].binsize double default=-1
+
+## Minimum value for maximum value of number of 'posocc' entries for a word.
+## The default is specified in fsearchrc.
+rankprofile[].posbinlow int default=-1
+
+## Maximum value for maximum value of number of 'posocc' entries for a word.
+## The default is specified in fsearchrc.
+rankprofile[].posbinhigh int default=-1
+
+## The maximum value for number of 'posocc' entries for a word, specified
+## as a percentage of the number of documents in the index.  If more
+## entries are needed for evaluation, posocc entries are not used for that
+## word and evaluation will be performed without full proximity support.
+## The percentage can be ramped off with the posbinlow and posbinhigh
+## variables. The default is specified in fsearchrc.
+rankprofile[].posbinsize int default=-1
+
+## After all other rank calculations, the rank value is tuned according
+## to the tunefactor and tunebias values. The rank value is modified
+## as follows: new_rank = old_rank * tunefactor + tunebias.
+rankprofile[].tunefactor double default=1.0
+
+## After all other rank calculations, the rank value is tuned according
+## to the tunefactor and tunebias values. The rank value is modified
+## as follows: new_rank = old_rank * tunefactor + tunebias.
+rankprofile[].tunebias int default=0
+
+## A lower limit for the rankvalue of the results returned from the
+## search node.  If rankcutoff.advanced is set to "true", determines
+## the constant value used in the internal advanced rank cutoff
+## calculations.  This roughly reflects the expected rank contribution
+## of one good term.
+## The rankcutoff.val value and the rankcutoff.advanced parameter
+## may be used if you only want hits with a minimum relevancy to show
+## up in the resultset.
+## A value below zero means no rankcutoff is done.
+rankprofile[].rankcutoff.val int default=-1
+
+## When rankcutoff.val is in use, this flag controls whether to use
+## an internal calculation is used for determining the rank cutoff
+## value. If "false", use rankcutoff.val as a direct lower limit.
+rankprofile[].rankcutoff.advanced bool default=false
+
+## If set to "ON", use of posocc files is enabled, except when
+## "forceemptyposoccs" is set in fsearchrc or posocc files doesn't exist.
+## If set to "OFF", use of posocc files is disabled.
+## If "NOTSET" the fsearchrc "proximity" parameter is used instead.
+rankprofile[].proximity.full.enable enum { OFF, ON, NOTSET } default=NOTSET
+
+## If set to "ON", use of firstoccproximity is enabled.
+## If set to "OFF", use of firstoccproximity is disabled.
+## When NOTSET use the firstoccproximity value in fsearchrc configuration.
+rankprofile[].proximity.firstocc.enable enum { OFF, ON, NOTSET } default=NOTSET
+
+## If set to "ON", use of proximity (cf. proximity and firstoccproximity)
+## will affect phrases in addition to single words.
+## If set to "OFF", proximity is never used for phrases.
+## When NOTSET use the phraseproximity value in fsearchrc configuration.
+rankprofile[].proximity.phrase.enable enum { OFF, ON, NOTSET } default=NOTSET
+
+## Selects behavior when proximity can be used for two words but not three
+## words while firstoccproximity can be used for three words.
+## If set to "ON", then use proximity for two words.
+## If set to "OFF", then use firstoccproximity for three words.
+## When NOTSET use the proximitypairbeforefirstoccproximitytriple value
+## in fsearchrc configuration.
+rankprofile[].proximity.pairbeforefirstocctriple.enable enum { OFF, ON, NOTSET } default=NOTSET
+
+## Selects behavior when proximity can be used for three words but not four
+## words while firstoccproximity can be used for four words.
+## If set to "ON", then use proximity for three words.
+## If set to "OFF", then use firstoccproximity for four words.
+## When NOTSET use the proximitytriplebeforefirstoccproximityquad value
+rankprofile[].proximity.triplebeforefirstoccquad.enable enum { OFF, ON, NOTSET } default=NOTSET
diff --git a/config/src/test/java/com/yahoo/vespa/config/configsglobal/qr-logging.cfg b/config/src/test/java/com/yahoo/vespa/config/configsglobal/qr-logging.cfg
new file mode 100755
index 00000000000..cc640619e3a
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/configsglobal/qr-logging.cfg
@@ -0,0 +1,44 @@
+logger com.yahoo
+speciallog[6]
+speciallog[0].name QueryAccessLog
+speciallog[0].type file
+speciallog[0].filehandler.name QueryAccessLog
+speciallog[0].filehandler.pattern logs/vespa/qrs/QueryAccessLog.%Y%m%d%H%M%S
+speciallog[0].filehandler.rotation "0 60 ..."
+speciallog[0].cachehandler.name QueryAccessLog
+speciallog[0].cachehandler.size 1000
+speciallog[1].name QueryResultLog
+speciallog[1].type cache
+speciallog[1].filehandler.name QueryResultLog
+speciallog[1].filehandler.pattern logs/vespa/qrs/QueryResultLog.%Y%m%d%H%M%S
+speciallog[1].filehandler.rotation "0 60 ..."
+speciallog[1].cachehandler.name QueryResultLog
+speciallog[1].cachehandler.size 1000
+speciallog[2].name ResultImpressionLog
+speciallog[2].type file
+speciallog[2].filehandler.name ResultImpressionLog
+speciallog[2].filehandler.pattern logs/vespa/qrs/ResultImpressionLog.%Y%m%d%H%M%S
+speciallog[2].filehandler.rotation "0 60 ..."
+speciallog[2].cachehandler.name ResultImpressionLog
+speciallog[2].cachehandler.size 1000
+speciallog[3].name ServiceEventLog
+speciallog[3].type cache
+speciallog[3].filehandler.name ServiceEventLog
+speciallog[3].filehandler.pattern logs/vespa/qrs/ServiceEventLog.%Y%m%d%H%M%S
+speciallog[3].filehandler.rotation "0 60 ..."
+speciallog[3].cachehandler.name ServiceEventLog
+speciallog[3].cachehandler.size 1000
+speciallog[4].name ServiceStatusLog
+speciallog[4].type off
+speciallog[4].filehandler.name ServiceStatusLog
+speciallog[4].filehandler.pattern logs/vespa/qrs/ServiceStatusLog.%Y%m%d%H%M%S
+speciallog[4].filehandler.rotation "0 60 ..."
+speciallog[4].cachehandler.name ServiceStatusLog
+speciallog[4].cachehandler.size 1000
+speciallog[5].name ServiceTraceLog
+speciallog[5].type parent
+speciallog[5].filehandler.name ServiceTraceLog
+speciallog[5].filehandler.pattern logs/vespa/qrs/ServiceTraceLog.%Y%m%d%H%M%S
+speciallog[5].filehandler.rotation "0 60 ..."
+speciallog[5].cachehandler.name ServiceTraceLog
+speciallog[5].cachehandler.size 1000
diff --git a/config/src/test/java/com/yahoo/vespa/config/configsglobal/qr-templates.3.cfg b/config/src/test/java/com/yahoo/vespa/config/configsglobal/qr-templates.3.cfg
new file mode 100644
index 00000000000..345c20157f9
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/configsglobal/qr-templates.3.cfg
@@ -0,0 +1,111 @@
+washing -0.45
+washer 0
+hey[2]
+hey[0].ho[1]
+hey[0].ho[0].lets[3]
+hey[0].ho[0].lets[0].go "slayer"
+hey[0].ho[0].lets[0].fishing -1
+hey[0].ho[0].lets[0].ref JA
+hey[0].ho[0].lets[1].go "gate"
+hey[0].ho[0].lets[1].ref :parent:
+hey[0].ho[0].lets[str].go "strung"
+hey[0].ho[0].me 0.0
+hey[fooo].ho[0]
+
+hey[0] 78
+
+longVal 500
+longWithRange -9000000000
+longArr[2]
+longArr[0] 0
+longArr[1] 1
+longArrWithRange[1]
+longArrWithRange[0] 9000000000
+
+bar.arrline[0] "foo"
+bar.arrline[1] "bar"
+
+fileVal "/nodefault/file"
+fileArr[2]
+fileArr[0] "keyb.com"
+fileArr[1] "2b4a64d0cb36d44ba8a52506d9fe480bf3511be6"
+
+urlprefix "foo"
+templateset[2]
+templateset[0].urlprefix "/basic"
+#templateset[0].mimetype "text/xml"
+templateset[0].encoding "ut\"f-8\n' <hit relevancy=\"$relevancy\">\n#foreach"
+templateset[0].headertemplate "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n<resultset totalhits=\"$result.hitCount\">\n"
+templateset[0].footertemplate "</resultset>\n"
+templateset[0].nohitstemplate "<empty/>\n"
+templateset[0].hittemplate "<hit relevancy=\"$relevancy\">\n#foreach( $key in $hit.getPropertyKeySet() )\n  <field name='$key'>$hit.getPropertyXML($key)</field>\n#end\n</hit>\n"
+templateset[0].errortemplate "<ERROR CODE=\"$result.error.code\">$result.error.message</ERROR>\n"
+templateset[1].urlprefix "/xsearch"
+templateset[1].mimetype "text/xml"
+templateset[1].encoding "utf-8"
+templateset[1].rankprofile 0
+templateset[1].headertemplate "<?xml version=\"1.0\" encoding=\"utf-8\" ?>\n<RESULTSET TOTALHITS=\"$result.hitCount\">\n"
+templateset[1].footertemplate "</RESULTSET>\n"
+templateset[1].nohitstemplate "0.56"
+templateset[1].hittemplate "<HIT RELEVANCY=\"$relevancy\" TYPE=\"$hit.typeString\">\n<FIELD NAME=\"uri\">$uri</FIELD>\n<FIELD NAME=\"category\">$category</FIELD>\n<FIELD NAME=\"bsumtitle\">$bsumtitle</FIELD>\n</HIT>\n"
+templateset[1].errortemplate "45"
+config[0].id :parent:
+config[0].autostart
+hi[0].there[0].e BATCH
+ilscript[music].name music
+ilscript[music].doctype music
+ilscript[music].content[1]
+ilscript[music].content[0] "\"music\" | summary sddocname | lowercase | index sddocname;"
+
+musum *
+
+auran "value=\"Confirm\"/></form>\"\"Tuna - step three."
+
+route[1]
+route[0].name "search/cluster.books2"
+route[0].selector "books.isbn=\"none\""
+route[0].feed "books"
+
+languages[3]
+languages[2] "swahili"
+
+languages2[2]
+languages2[0] "swedish"
+
+foolang[5]
+foolang[0].lang[3]
+foolang[0].lang[1] "Swahili"
+foolang[1].lang[3]
+foolang[2].lang[3]
+foolang[2].lang[0] "Setswana"
+foolang[3].lang[4]
+foolang[3].lang[3] "Norwegian"
+foolang[4].lang[2]
+
+myIntMap{"foo"} 67
+myIntMap{"bar"} 68
+myStringMap{"fo"} "gh"
+myStringMap{"ba"} "ij"
+myStructMap{"FOO"}.myInt 78
+myStructMap{"FOO"}.myString "myFoo"
+myStructMap{"FOOO"}.myInt 89
+myStructMap{"FOOO"}.myString "myFooS"
+myStructMap{"FOOO"}.myIntDef -99
+myStructMap{"FOOO"}.myStringDef "myFooSBall"
+
+myStructMap{"FOO"}.myStruct.a "guitar"
+myStructMap{"FOO"}.myStruct.c /tmp
+
+myStructMap{"FOOO"}.myStruct.a "bass"
+myStructMap{"FOOO"}.myStruct.b "drums"
+myStructMap{"FOOO"}.myStruct.c /var/log
+
+myStructMap{"FOO"}.myStructNestedArray[0] -9
+myStructMap{"FOO"}.myStructNestedArray[1] -10
+
+myStructMap{"FOO"}.myNestedLeafMap{"Nested1"} 90
+myStructMap{"FOO"}.myNestedLeafMap{"Nested2"} 9000
+
+myStructMap{"FOO"}.myNestedMap{"Nested3"}.myLong 809
+myStructMap{"FOO"}.myNestedMap{"Nested3"}.myLongDef 810
+myStructMap{"FOO"}.myNestedMap{"Nested4"}.myLong 811
diff --git a/config/src/test/java/com/yahoo/vespa/config/configsglobal/testfoobar.12.cfg b/config/src/test/java/com/yahoo/vespa/config/configsglobal/testfoobar.12.cfg
new file mode 100644
index 00000000000..3d23f7fd29a
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/configsglobal/testfoobar.12.cfg
@@ -0,0 +1,105 @@
+vh[5]
+vh[0] 0.3345
+vh[1] -0.3
+vh[2] 134.3
+vh[3] 234.34
+vh[4] -24.3
+bg[5]
+bg[0] 5
+bg[1]
+bg[2] 10
+bg[3] 4
+bg[4] -2
+gee[2]
+gee[0] "jabbaTuna"
+gee[1] jabba:500/dusteri
+storage[2]
+storage[0].distributor[2]
+storage[0].distributor[0] "tra"
+storage[0].distributor[1] "de"
+storage[0].feeder[1]
+storage[0].feeder[0] "li"
+#storage[0].feeder[1] "dum"
+storage[1].distributor[3]
+storage[1].distributor[0] "Etra"
+storage[1].distributor[1] "Ede"
+#storage[1].feeder[3]
+storage[1].feeder[0] "Eli"
+storage[1].feeder[1] "Edum"
+storage[1].feeder[2] "TEdum"
+
+#ju[].hu[].tu[] double default=45 range=[0,100.1]
+#ju[].hu[].wu[] enum { HEY, HO} default=HO
+#ju[].hu[].tang[] bool default=false
+#ju[].hu[].clan[] int default=45 range=[-90,90]
+
+ju[2]
+ju[0].hu[2]
+ju[0].hu[0].tu[2]
+ju[0].hu[0].tu[0] 45.0
+ju[0].hu[0].tu[1] 0.0
+ju[0].hu[0].tang[2]
+ju[0].hu[0].tang[0] true
+#ju[0].hu[0].tang[1] 0.0
+
+#ju[0].hu[1].tu[2]
+ju[0].hu[1].tu[0] 667.865
+ju[0].hu[0].wu[2]
+ju[0].hu[0].wu[0] HEY
+ju[0].hu[0].wu[1] HEY
+ju[0].hu[1].wu[1]
+ju[0].hu[1].wu[0] HO
+
+ju[1].hu[2]
+ju[1].hu[0].tu[2]
+ju[1].hu[0].tu[0] 78
+ju[1].hu[0].tu[1] 78.9
+ju[1].hu[1].tu[1]
+ju[1].hu[1].tu[0] 88.9
+
+ju[1].hu[0].wu[3]
+ju[1].hu[0].wu[0] HEY
+ju[1].hu[0].wu[1] HEY
+ju[1].hu[0].wu[2] HO
+ju[1].hu[1].wu[1]
+ju[1].hu[1].wu[0] HO
+ju[1].hu[1].clan[4]
+ju[1].hu[1].clan[0] 5
+ju[1].hu[1].clan[1] 6
+ju[1].hu[1].clan[2] 7
+ju[1].hu[1].clan[3] 8
+foo "123aaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaaa gh:sann\" da"
+headertemplate "<!DOCTYPE HTML PUBLIC \"-//W3C//DTD HTML 4.0 Transitional//EN\">\n<html>\n<head>\n<title>ranqualizer:$hostname:$profile:</title>\n<link type=\"text/css\" rel=\"stylesheet\" href=\"/layout.css\"/>\n<meta name=\"ROBOTS\" content=\"NOINDEX,NOFOLLOW\"/><meta http-equiv=\"Cache-control\" content=\"no-cache\"/><meta http-equiv=\"Cache-control\" content=\"must-revalidate\"/><meta http-equiv=\"Cache-control\" content=\"max-age=0\"/><meta http-equiv=\"Content-type\" content=\"text/html; charset=utf-8\"/><link rel=\"icon\" href=\"/favicon.ico\"/><script type=\"text/javascript\">function show(foo,f){document.getElementById(foo).style.display=\"block\";} function hide(foo,f){document.getElementById(foo).style.display = \"none\";}</script></head>\n<body>\n"
+ptport  10108
+rankcf :parent:
+hport   10109
+frtport 10107
+transportnodelay true
+partition 0
+datasetdir none
+proximity "yes"
+vsmconfig ""
+documentmanagerconfigid :parent:
+include: search/cluster.music
+include: search/cluster.music2
+
+rankprofile[extra].fef.property[4]
+rankprofile[ignore].fef.property[4].name "vespa.dump.ignoredefaultfeatures"
+rankprofile[ignore].fef.property[4].value true
+
+specialchars "索 索尼 DVD±R"
+
+tokenlist[1]
+tokenlist[0].name "default"
+tokenlist[0].tokens[8]
+tokenlist[0].tokens[0].token "c++"
+tokenlist[0].tokens[1].token "wal-mart"
+tokenlist[0].tokens[1].replace "walmart"
+tokenlist[0].tokens[2].token ".net"
+tokenlist[0].tokens[3].token "-索"
+tokenlist[0].tokens[4].token "sony"
+tokenlist[0].tokens[4].replace "索尼"
+tokenlist[0].tokens[5].token "dvd+-r"
+tokenlist[0].tokens[6].token "DVD±R"
+tokenlist[0].tokens[7].token "dvdplusminusr"
+tokenlist[0].tokens[7].replace "dvd+-r"
diff --git a/config/src/test/java/com/yahoo/vespa/config/protocol/ConfigResponseTest.java b/config/src/test/java/com/yahoo/vespa/config/protocol/ConfigResponseTest.java
new file mode 100644
index 00000000000..e39c0a6f623
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/protocol/ConfigResponseTest.java
@@ -0,0 +1,66 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.foo.SimpletypesConfig;
+import com.yahoo.config.codegen.DefParser;
+import com.yahoo.config.codegen.InnerCNode;
+import com.yahoo.text.StringUtilities;
+import com.yahoo.text.Utf8Array;
+import com.yahoo.vespa.config.ConfigPayload;
+import com.yahoo.vespa.config.LZ4PayloadCompressor;
+import org.junit.Test;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.io.StringReader;
+import java.util.List;
+
+import static org.hamcrest.core.Is.is;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertThat;
+
+/**
+ * @author lulf
+ * @since 5.1
+ */
+public class ConfigResponseTest {
+
+    @Test
+    public void require_that_slime_response_is_initialized() throws IOException {
+        ConfigPayload configPayload = ConfigPayload.fromInstance(new SimpletypesConfig(new SimpletypesConfig.Builder()));
+        DefParser dParser = new DefParser(SimpletypesConfig.getDefName(), new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n")));
+        InnerCNode targetDef = dParser.getTree();
+        ConfigResponse response = SlimeConfigResponse.fromConfigPayload(configPayload, targetDef, 3, "mymd5");
+        List<String> payload = response.getLegacyPayload();
+        assertNotNull(payload);
+        assertThat(payload.size(), is(6));
+        assertThat(payload.get(0), is("boolval false"));
+        assertThat(response.getGeneration(), is(3l));
+        assertThat(response.getConfigMd5(), is("mymd5"));
+
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        response.serialize(baos, CompressionType.UNCOMPRESSED);
+        assertThat(baos.toString(), is("{\"boolval\":false,\"doubleval\":0.0,\"enumval\":\"VAL1\",\"intval\":0,\"longval\":0,\"stringval\":\"s\"}"));
+    }
+
+    @Test
+    public void require_that_slime_response_decompresses_on_serialize() throws IOException {
+
+        ConfigPayload configPayload = ConfigPayload.fromInstance(new SimpletypesConfig(new SimpletypesConfig.Builder()));
+        DefParser dParser = new DefParser(SimpletypesConfig.getDefName(), new StringReader(StringUtilities.implode(SimpletypesConfig.CONFIG_DEF_SCHEMA, "\n")));
+        InnerCNode targetDef = dParser.getTree();
+        Utf8Array data = configPayload.toUtf8Array(true);
+        Utf8Array bytes = new Utf8Array(new LZ4PayloadCompressor().compress(data.getBytes()));
+        ConfigResponse response = new SlimeConfigResponse(bytes, targetDef, 3, "mymd5", CompressionInfo.create(CompressionType.LZ4, data.getByteLength()));
+        List<String> payload = response.getLegacyPayload();
+        assertNotNull(payload);
+        assertThat(payload.size(), is(6));
+        assertThat(payload.get(0), is("boolval false"));
+        assertThat(response.getGeneration(), is(3l));
+        assertThat(response.getConfigMd5(), is("mymd5"));
+
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        response.serialize(baos, CompressionType.UNCOMPRESSED);
+        assertThat(baos.toString(), is("{\"boolval\":false,\"doubleval\":0.0,\"enumval\":\"VAL1\",\"intval\":0,\"longval\":0,\"stringval\":\"s\"}"));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/protocol/JRTConfigRequestBase.java b/config/src/test/java/com/yahoo/vespa/config/protocol/JRTConfigRequestBase.java
new file mode 100644
index 00000000000..0cf6491432d
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/protocol/JRTConfigRequestBase.java
@@ -0,0 +1,286 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.foo.SimpletypesConfig;
+import com.yahoo.config.subscription.ConfigSet;
+import com.yahoo.config.subscription.ConfigSourceSet;
+import com.yahoo.config.subscription.ConfigSubscriber;
+import com.yahoo.config.subscription.impl.GenericConfigSubscriber;
+import com.yahoo.config.subscription.impl.JRTConfigRequester;
+import com.yahoo.config.subscription.impl.JRTConfigSubscription;
+import com.yahoo.config.subscription.impl.MockConnection;
+import com.yahoo.jrt.Request;
+import com.yahoo.slime.Inspector;
+import com.yahoo.slime.JsonDecoder;
+import com.yahoo.slime.Slime;
+import com.yahoo.test.ManualClock;
+import com.yahoo.text.Utf8;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.ConfigPayload;
+import com.yahoo.vespa.config.ErrorCode;
+import com.yahoo.vespa.config.RawConfig;
+import com.yahoo.vespa.config.TimingValues;
+import com.yahoo.vespa.config.util.ConfigUtils;
+import org.junit.Before;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.util.Collections;
+import java.util.Optional;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertNotNull;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author lulf
+ * @since 5.3
+ */
+public abstract class JRTConfigRequestBase {
+
+    protected String defName = "mydef";
+    protected String defNamespace = "my.name.space";
+    protected String hostname = "myhost";
+    protected String configId = "config/id";
+    protected String defMd5 = "595f44fec1e92a71d3e9e77456ba80d1";
+    protected long currentGeneration = 3;
+    protected final Optional<VespaVersion> vespaVersion = Optional.of(VespaVersion.fromString("5.38.24"));
+    protected long timeout = 5000;
+    protected Trace trace ;
+    protected String configMd5 = ConfigUtils.getMd5(createPayload().getData());
+    protected JRTClientConfigRequest clientReq;
+    protected JRTServerConfigRequest serverReq;
+
+    @Before
+    public void setupRequest() throws IOException {
+        clientReq = createReq();
+        serverReq = createReq(clientReq.getRequest());
+        assertTrue(serverReq.validateParameters());
+    }
+
+    private JRTClientConfigRequest createReq() throws IOException {
+        trace = Trace.createNew(3, new ManualClock());
+        trace.trace(1, "hei");
+        return createReq(defName, defNamespace, defMd5, hostname, configId, configMd5, currentGeneration, timeout, trace);
+    }
+
+    private JRTClientConfigRequest createReq(Payload payload) throws IOException {
+        trace = Trace.createNew(3, new ManualClock());
+        trace.trace(1, "hei");
+        return createReq(defName, defNamespace, defMd5, hostname, configId, ConfigUtils.getMd5(payload.getData()), currentGeneration, timeout, trace);
+    }
+
+    protected abstract JRTClientConfigRequest createReq(String defName, String defNamespace, String defMd5, String hostname, String configId, String  configMd5, long currentGeneration, long timeout, Trace trace) throws IOException;
+    protected abstract JRTServerConfigRequest createReq(Request request);
+    protected abstract JRTClientConfigRequest createReq(JRTConfigSubscription<SimpletypesConfig> sub, Trace aNew);
+    protected abstract JRTClientConfigRequest createFromRaw(RawConfig rawConfig, long serverTimeout, Trace aNew);
+
+    protected void request_is_parsed_base() {
+        String [] expectedContent = new String[]{
+                "namespace=my.name.space",
+                "myfield string"
+        };
+        System.out.println(serverReq.toString());
+        assertThat(serverReq.getConfigKey().getName(), is(defName));
+        assertThat(serverReq.getConfigKey().getNamespace(), is(defNamespace));
+        assertThat(serverReq.getConfigKey().getMd5(), is(defMd5));
+        assertThat(serverReq.getConfigKey().getConfigId(), is(configId));
+        assertThat(serverReq.getDefContent().asStringArray(), is(expectedContent));
+        assertFalse(serverReq.noCache());
+        assertTrue(serverReq.getRequestTrace().toString().contains("hi"));
+        assertThat(serverReq.getRequestConfigMd5(), is(configMd5));
+        assertThat(serverReq.getRequestGeneration(), is(currentGeneration));
+    }
+
+    @Test
+    public void delay_mechanisms_functions() {
+        assertFalse(serverReq.isDelayedResponse());
+        serverReq.setDelayedResponse(true);
+        assertTrue(serverReq.isDelayedResponse());
+        serverReq.setDelayedResponse(false);
+        assertFalse(serverReq.isDelayedResponse());
+    }
+
+    public JRTServerConfigRequest next_request_is_correct_base() {
+        String [] expectedContent = new String[]{
+                "namespace=my.name.space",
+                "myfield string"
+        };
+        JRTServerConfigRequest next = createReq(clientReq.nextRequest(6).getRequest());
+        assertThat(next.getConfigKey().getName(), is(defName));
+        assertThat(next.getConfigKey().getNamespace(), is(defNamespace));
+        assertThat(next.getConfigKey().getMd5(), is(defMd5));
+        assertThat(next.getConfigKey().getConfigId(), is(configId));
+        assertThat(next.getDefContent().asStringArray(), is(expectedContent));
+        assertFalse(next.noCache());
+        assertThat(next.getTimeout(), is(6l));
+        assertThat(next.getTimeout(), is(6l));
+        return next;
+    }
+
+
+    @Test
+    public void next_request_when_error_is_correct() {
+        serverReq.addOkResponse(createPayload(), 999999, "newmd5");
+        serverReq.addErrorResponse(ErrorCode.OUTDATED_CONFIG, "error message");
+        System.out.println(serverReq);
+        JRTClientConfigRequest next = clientReq.nextRequest(6);
+        System.out.println(next);
+        // Should use config md5 and generation from the request, not the response
+        // when there are errors
+        assertThat(next.getRequestConfigMd5(), is(clientReq.getRequestConfigMd5()));
+        assertThat(next.getRequestGeneration(), is(clientReq.getRequestGeneration()));
+    }
+
+    @Test
+    public void ok_response_is_added() {
+        Payload payload = createPayload("vale");
+        String md5 = ConfigUtils.getMd5(payload.getData());
+        long generation = 4l;
+        serverReq.addOkResponse(payload, generation, md5);
+        assertTrue(clientReq.validateResponse());
+        assertThat(clientReq.getNewPayload().withCompression(CompressionType.UNCOMPRESSED).getData().toString(), is(payload.getData().toString()));
+        assertThat(clientReq.getNewGeneration(), is(4l));
+        assertThat(clientReq.getNewConfigMd5(), is(md5));
+        assertTrue(clientReq.hasUpdatedConfig());
+        assertTrue(clientReq.hasUpdatedGeneration());
+    }
+
+    @Test
+    public void error_response_adds_common_elements() {
+        serverReq.addErrorResponse(ErrorCode.APPLICATION_NOT_LOADED, ErrorCode.getName(ErrorCode.APPLICATION_NOT_LOADED));
+        assertThat(serverReq.getRequest().returnValues().size(), is(1));
+        Slime data = new JsonDecoder().decode(new Slime(), Utf8.toBytes(serverReq.getRequest().returnValues().get(0).asString()));
+        Inspector response = data.get();
+        assertThat(response.field(SlimeResponseData.RESPONSE_DEF_NAME).asString(), is(defName));
+        assertThat(response.field(SlimeResponseData.RESPONSE_DEF_NAMESPACE).asString(), is(defNamespace));
+        assertThat(response.field(SlimeResponseData.RESPONSE_DEF_MD5).asString(), is(defMd5));
+        assertThat(response.field(SlimeResponseData.RESPONSE_CONFIGID).asString(), is(configId));
+        assertThat(response.field(SlimeResponseData.RESPONSE_CLIENT_HOSTNAME).asString(), is(hostname));
+        Trace t = Trace.fromSlime(response.field(SlimeResponseData.RESPONSE_TRACE));
+        assertThat(t.toString(), is(trace.toString()));
+    }
+
+    @Test
+    public void generation_only_is_updated() {
+        Payload payload = createPayload();
+        serverReq.addOkResponse(payload, 4l, ConfigUtils.getMd5(payload.getData()));
+        boolean value = clientReq.validateResponse();
+        assertTrue(clientReq.errorMessage(), value);
+        assertFalse(clientReq.hasUpdatedConfig());
+        assertTrue(clientReq.hasUpdatedGeneration());
+    }
+
+    protected static Payload createPayload() {
+        return createPayload("bar");
+    }
+
+    private static Payload createPayload(String value) {
+        Slime slime = new Slime();
+        slime.setObject().setString("myfield", value);
+        return Payload.from(new ConfigPayload(slime));
+    }
+
+    @Test
+    public void nothing_is_updated() {
+        Payload payload = createPayload();
+        serverReq.addOkResponse(payload, currentGeneration, configMd5);
+        assertTrue(clientReq.validateResponse());
+        assertFalse(clientReq.hasUpdatedConfig());
+        assertFalse(clientReq.hasUpdatedGeneration());
+    }
+
+    @Test
+    public void payload_is_empty() throws IOException {
+        Payload payload = Payload.from(ConfigPayload.empty());
+        clientReq = createReq(payload);
+        serverReq = createReq(clientReq.getRequest());
+        serverReq.addOkResponse(payload, currentGeneration, ConfigUtils.getMd5(payload.getData()));
+        boolean val = clientReq.validateResponse();
+        assertTrue(clientReq.errorMessage(), val);
+        assertFalse(clientReq.hasUpdatedConfig());
+        assertFalse(clientReq.hasUpdatedGeneration());
+    }
+
+    @Test
+    public void request_interface_is_implemented() {
+        JRTClientConfigRequest request = clientReq;
+        assertFalse(request.containsPayload());
+        assertFalse(request.isError());
+        assertThat(request.errorCode(), is(clientReq.getRequest().errorCode()));
+        assertThat(request.errorMessage(), is(clientReq.getRequest().errorMessage()));
+        assertNotNull(request.getRequest());
+        assertFalse(request.validateResponse());
+        //assertNull(request.getNewPayload().getData());
+        assertThat(request.getTimeout(), is(timeout));
+        assertFalse(request.hasUpdatedConfig());
+        assertFalse(request.hasUpdatedGeneration());
+    }
+
+    @Test
+    public void created_from_subscription() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        JRTConfigSubscription<SimpletypesConfig> sub = new JRTConfigSubscription<>(new ConfigKey<>(SimpletypesConfig.class, configId), subscriber, new ConfigSet(), new TimingValues());
+        JRTClientConfigRequest request = createReq(sub, Trace.createNew(9));
+        assertThat(request.getConfigKey().getName(), is(SimpletypesConfig.CONFIG_DEF_NAME));
+        JRTServerConfigRequest serverRequest = createReq(request.getRequest());
+        assertTrue(serverRequest.validateParameters());
+    }
+
+    @Test
+    public void created_from_existing_subscription() {
+        System.setProperty("VESPA_CONFIG_PROTOCOL_VERSION", getProtocolVersion());
+        MockConnection connection = new MockConnection(new MockConnection.AbstractResponseHandler() {
+            @Override
+            protected void createResponse() {
+                JRTServerConfigRequest serverRequest = createReq(request);
+                serverRequest.addOkResponse(createPayload(), currentGeneration, configMd5);
+            }
+        });
+
+        ConfigSourceSet src = new ConfigSourceSet();
+        ConfigSubscriber subscriber = new GenericConfigSubscriber(Collections.singletonMap(src, JRTConfigRequester.get(connection, new TimingValues())));
+        JRTConfigSubscription<SimpletypesConfig> sub = new JRTConfigSubscription<>(new ConfigKey<>(SimpletypesConfig.class, configId), subscriber, src, new TimingValues());
+        sub.subscribe(120_0000);
+        assertTrue(sub.nextConfig(120_0000));
+        sub.close();
+        JRTClientConfigRequest nextReq = createReq(sub, Trace.createNew());
+        SimpletypesConfig config = sub.getConfig();
+        assertThat(nextReq.getRequestConfigMd5(), is(config.getConfigMd5()));
+        assertThat(nextReq.getRequestGeneration(), is(currentGeneration));
+        System.setProperty("VESPA_CONFIG_PROTOCOL_VERSION", "");
+    }
+
+    protected abstract String getProtocolVersion();
+
+    @Test
+    public void created_from_raw() throws IOException {
+        RawConfig rawConfig = new RawConfig(new ConfigKey<>(defName, configId, defNamespace), defMd5);
+        long serverTimeout = 100000L;
+        JRTClientConfigRequest request = createFromRaw(rawConfig, serverTimeout, Trace.createNew(9));
+        assertThat(request.getConfigKey().getName(), is(defName));
+        JRTServerConfigRequest serverRequest = createReq(request.getRequest());
+        assertTrue(serverRequest.validateParameters());
+        assertThat(serverRequest.getTimeout(), is(serverTimeout));
+        assertThat(serverRequest.getDefContent().asList(), is(rawConfig.getDefContent()));
+    }
+
+
+    @Test
+    public void parameters_are_validated() throws IOException {
+        assertTrue(serverReq.validateParameters());
+        assertValidationFail(createReq("35#$#!$@#", defNamespace, defMd5, hostname, configId, configMd5, currentGeneration, timeout, trace));
+        assertValidationFail(createReq(defName, "abcd.o#$*(!&$", defMd5, hostname, configId, configMd5, currentGeneration, timeout, trace));
+        assertValidationFail(createReq(defName, defNamespace, "34", hostname, configId, "34", currentGeneration, timeout, trace));
+        assertValidationFail(createReq(defName, defNamespace, defMd5, hostname, configId, "34", currentGeneration, timeout, trace));
+        assertValidationFail(createReq(defName, defNamespace, defMd5, hostname, configId, configMd5, -34, timeout, trace));
+        assertValidationFail(createReq(defName, defNamespace, defMd5, hostname, configId, configMd5, currentGeneration, -23, trace));
+        assertValidationFail(createReq(defName, defNamespace, defMd5, "", configId, configMd5, currentGeneration, timeout, trace));
+    }
+
+    private void assertValidationFail(JRTClientConfigRequest req) {
+        assertFalse(createReq(req.getRequest()).validateParameters());
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/protocol/JRTConfigRequestFactoryTest.java b/config/src/test/java/com/yahoo/vespa/config/protocol/JRTConfigRequestFactoryTest.java
new file mode 100644
index 00000000000..ac3a7f16505
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/protocol/JRTConfigRequestFactoryTest.java
@@ -0,0 +1,143 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.foo.FunctionTestConfig;
+import com.yahoo.config.subscription.ConfigSet;
+import com.yahoo.config.subscription.ConfigSubscriber;
+import com.yahoo.config.subscription.impl.JRTConfigSubscription;
+import com.yahoo.vespa.config.ConfigKey;
+import com.yahoo.vespa.config.RawConfig;
+import com.yahoo.vespa.config.TimingValues;
+import org.junit.Test;
+
+import java.util.Optional;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.MatcherAssert.assertThat;
+
+/**
+ * @author musum
+ */
+public class JRTConfigRequestFactoryTest {
+    private static VespaVersion defaultVespaVersion = JRTConfigRequestFactory.getCompiledVespaVersion();
+
+    @Test
+    public void testGetProtocolVersion() {
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("", "", ""), is("3"));
+
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("1", "", ""), is("1"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("", "1", ""), is("1"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("", "", "1"), is("1"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("1", "1", ""), is("1"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("1", "", "1"), is("1"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("", "1", "1"), is("1"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("1", "1", "1"), is("1"));
+
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("2", "", ""), is("2"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("", "2", ""), is("2"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("", "", "2"), is("2"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("2", "2", ""), is("2"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("2", "", "2"), is("2"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("", "2", "2"), is("2"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("2", "2", "2"), is("2"));
+
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("1", "2", ""), is("1"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("1", "", "2"), is("1"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("", "1", "2"), is("1"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("2", "1", ""), is("2"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("2", "", "1"), is("2"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("", "2", "1"), is("2"));
+
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("1", "2", "2"), is("1"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("1", "1", "2"), is("1"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("1", "2", "1"), is("1"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("2", "1", "1"), is("2"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("2", "1", "2"), is("2"));
+        assertThat(JRTConfigRequestFactory.getProtocolVersion("2", "2", "1"), is("2"));
+    }
+
+    @Test
+    public void testCompressionType() {
+        assertThat(JRTConfigRequestFactory.getCompressionType("", "", ""), is(CompressionType.LZ4));
+
+        assertThat(JRTConfigRequestFactory.getCompressionType("UNCOMPRESSED", "", ""), is(CompressionType.UNCOMPRESSED));
+        assertThat(JRTConfigRequestFactory.getCompressionType("", "UNCOMPRESSED", ""), is(CompressionType.UNCOMPRESSED));
+        assertThat(JRTConfigRequestFactory.getCompressionType("", "", "UNCOMPRESSED"), is(CompressionType.UNCOMPRESSED));
+        assertThat(JRTConfigRequestFactory.getCompressionType("UNCOMPRESSED", "UNCOMPRESSED", ""), is(CompressionType.UNCOMPRESSED));
+        assertThat(JRTConfigRequestFactory.getCompressionType("UNCOMPRESSED", "", "UNCOMPRESSED"), is(CompressionType.UNCOMPRESSED));
+        assertThat(JRTConfigRequestFactory.getCompressionType("", "UNCOMPRESSED", "UNCOMPRESSED"), is(CompressionType.UNCOMPRESSED));
+        assertThat(JRTConfigRequestFactory.getCompressionType("UNCOMPRESSED", "UNCOMPRESSED", "UNCOMPRESSED"), is(CompressionType.UNCOMPRESSED));
+
+        assertThat(JRTConfigRequestFactory.getCompressionType("LZ4", "", ""), is(CompressionType.LZ4));
+        assertThat(JRTConfigRequestFactory.getCompressionType("", "LZ4", ""), is(CompressionType.LZ4));
+        assertThat(JRTConfigRequestFactory.getCompressionType("", "", "LZ4"), is(CompressionType.LZ4));
+        assertThat(JRTConfigRequestFactory.getCompressionType("LZ4", "LZ4", ""), is(CompressionType.LZ4));
+        assertThat(JRTConfigRequestFactory.getCompressionType("LZ4", "", "LZ4"), is(CompressionType.LZ4));
+        assertThat(JRTConfigRequestFactory.getCompressionType("", "LZ4", "LZ4"), is(CompressionType.LZ4));
+        assertThat(JRTConfigRequestFactory.getCompressionType("LZ4", "LZ4", "LZ4"), is(CompressionType.LZ4));
+
+        assertThat(JRTConfigRequestFactory.getCompressionType("UNCOMPRESSED", "LZ4", ""), is(CompressionType.UNCOMPRESSED));
+        assertThat(JRTConfigRequestFactory.getCompressionType("UNCOMPRESSED", "", "LZ4"), is(CompressionType.UNCOMPRESSED));
+        assertThat(JRTConfigRequestFactory.getCompressionType("", "UNCOMPRESSED", "LZ4"), is(CompressionType.UNCOMPRESSED));
+        assertThat(JRTConfigRequestFactory.getCompressionType("LZ4", "UNCOMPRESSED", ""), is(CompressionType.LZ4));
+        assertThat(JRTConfigRequestFactory.getCompressionType("LZ4", "", "UNCOMPRESSED"), is(CompressionType.LZ4));
+        assertThat(JRTConfigRequestFactory.getCompressionType("", "LZ4", "UNCOMPRESSED"), is(CompressionType.LZ4));
+
+        assertThat(JRTConfigRequestFactory.getCompressionType("UNCOMPRESSED", "LZ4", "LZ4"), is(CompressionType.UNCOMPRESSED));
+        assertThat(JRTConfigRequestFactory.getCompressionType("UNCOMPRESSED", "UNCOMPRESSED", "LZ4"), is(CompressionType.UNCOMPRESSED));
+        assertThat(JRTConfigRequestFactory.getCompressionType("UNCOMPRESSED", "LZ4", "UNCOMPRESSED"), is(CompressionType.UNCOMPRESSED));
+        assertThat(JRTConfigRequestFactory.getCompressionType("LZ4", "UNCOMPRESSED", "UNCOMPRESSED"), is(CompressionType.LZ4));
+        assertThat(JRTConfigRequestFactory.getCompressionType("LZ4", "UNCOMPRESSED", "LZ4"), is(CompressionType.LZ4));
+        assertThat(JRTConfigRequestFactory.getCompressionType("LZ4", "LZ4", "UNCOMPRESSED"), is(CompressionType.LZ4));
+    }
+
+    @Test
+    public void testVespaVersion() {
+        assertThat(JRTConfigRequestFactory.getVespaVersion().get(), is(defaultVespaVersion));
+    }
+
+    @Test
+    public void testCreateFromSub() {
+        ConfigSubscriber subscriber = new ConfigSubscriber();
+        Class<FunctionTestConfig> clazz = FunctionTestConfig.class;
+        final String configId = "foo";
+        JRTConfigSubscription<FunctionTestConfig> sub = new JRTConfigSubscription<>(
+                new ConfigKey<>(clazz, configId), subscriber, new ConfigSet(), new TimingValues());
+
+        // Default vespa version
+        JRTClientConfigRequest request = JRTConfigRequestFactory.createFromSub(sub);
+        assertThat(request.getProtocolVersion(), is(3L));
+        assertThat(request.getVespaVersion().get(), is(defaultVespaVersion));
+
+        // Create with vespa version set
+        String version = "5.37.38";
+        System.setProperty(JRTConfigRequestFactory.VESPA_VERSION, version);
+        request = JRTConfigRequestFactory.createFromSub(sub);
+        assertThat(request.getProtocolVersion(), is(3L));
+        assertThat(request.getVespaVersion().get(), is(VespaVersion.fromString(version)));
+
+        System.clearProperty(JRTConfigRequestFactory.VESPA_VERSION);
+    }
+
+    @Test
+    public void testCreateFromRaw() {
+        Class<FunctionTestConfig> clazz = FunctionTestConfig.class;
+        final String configId = "foo";
+        RawConfig config = new RawConfig(new ConfigKey<>(clazz, configId), "595f44fec1e92a71d3e9e77456ba80d1");
+
+        // Default vespa version
+        JRTClientConfigRequest request = JRTConfigRequestFactory.createFromRaw(config, 1000);
+        assertThat(request.getProtocolVersion(), is(3L));
+        assertThat(request.getVespaVersion().get(), is(defaultVespaVersion));
+
+        // Create with vespa version set
+        String version = "5.37.38";
+        System.setProperty(JRTConfigRequestFactory.VESPA_VERSION, version);
+        request = JRTConfigRequestFactory.createFromRaw(config, 1000);
+        assertThat(request.getProtocolVersion(), is(3L));
+        assertThat(request.getVespaVersion().get(), is(VespaVersion.fromString(version)));
+
+        System.clearProperty(JRTConfigRequestFactory.VESPA_VERSION);
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/protocol/JRTConfigRequestV3Test.java b/config/src/test/java/com/yahoo/vespa/config/protocol/JRTConfigRequestV3Test.java
new file mode 100644
index 00000000000..bcb88b2ff5e
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/protocol/JRTConfigRequestV3Test.java
@@ -0,0 +1,78 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.foo.SimpletypesConfig;
+import com.yahoo.config.subscription.impl.JRTConfigSubscription;
+import com.yahoo.jrt.Request;
+import com.yahoo.vespa.config.*;
+import com.yahoo.vespa.config.util.ConfigUtils;
+import org.junit.Test;
+
+import java.io.IOException;
+import java.util.Arrays;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author lulf
+ * @since 5.19
+ */
+public class JRTConfigRequestV3Test extends JRTConfigRequestBase {
+
+    @Override
+    protected JRTClientConfigRequest createReq(String defName, String defNamespace, String defMd5, String hostname, String configId, String configMd5, long currentGeneration, long timeout, Trace trace) throws IOException {
+        return JRTClientConfigRequestV3.createWithParams(ConfigKey.createFull(defName, configId, defNamespace, defMd5),
+                DefContent.fromList(Arrays.asList("namespace=my.name.space", "myfield string")),
+                hostname,
+                configMd5,
+                currentGeneration,
+                timeout,
+                trace,
+                CompressionType.LZ4,
+                vespaVersion);
+    }
+
+    @Override
+    protected JRTServerConfigRequest createReq(Request request) {
+        return JRTServerConfigRequestV3.createFromRequest(request);
+    }
+
+    @Override
+    protected JRTClientConfigRequest createReq(JRTConfigSubscription<SimpletypesConfig> sub, Trace aNew) {
+        return JRTClientConfigRequestV3.createFromSub(sub, aNew, CompressionType.LZ4, vespaVersion);
+    }
+
+    @Override
+    protected JRTClientConfigRequest createFromRaw(RawConfig rawConfig, long serverTimeout, Trace aNew) {
+        return JRTClientConfigRequestV3.createFromRaw(rawConfig, serverTimeout, aNew, CompressionType.LZ4, vespaVersion);
+    }
+
+    @Override
+    protected String getProtocolVersion() {
+        return "3";
+    }
+
+    @Test
+    public void request_is_parsed() {
+        request_is_parsed_base();
+        assertThat(serverReq.getVespaVersion().toString(), is(vespaVersion.toString()));
+    }
+
+    @Test
+    public void next_request_is_correct() {
+        JRTServerConfigRequest next = next_request_is_correct_base();
+        assertThat(next.getVespaVersion().toString(), is(vespaVersion.toString()));
+    }
+
+    @Test
+    public void emptypayload() {
+        ConfigPayload payload = ConfigPayload.empty();
+        SlimeConfigResponse response = SlimeConfigResponse.fromConfigPayload(payload, null, 0, ConfigUtils.getMd5(payload));
+        serverReq.addOkResponse(serverReq.payloadFromResponse(response), response.getGeneration(), response.getConfigMd5());
+        assertTrue(clientReq.validateResponse());
+        assertTrue(clientReq.hasUpdatedGeneration());
+        assertThat(clientReq.getNewPayload().withCompression(CompressionType.UNCOMPRESSED).getData().toString(), is("{}"));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/protocol/PayloadTest.java b/config/src/test/java/com/yahoo/vespa/config/protocol/PayloadTest.java
new file mode 100644
index 00000000000..c3cbfecf1f1
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/protocol/PayloadTest.java
@@ -0,0 +1,85 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.google.common.testing.EqualsTester;
+import com.yahoo.slime.Slime;
+import com.yahoo.text.Utf8Array;
+import com.yahoo.vespa.config.ConfigPayload;
+import com.yahoo.vespa.config.LZ4PayloadCompressor;
+import org.junit.Test;
+
+import java.io.UnsupportedEncodingException;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertEquals;
+import static org.junit.Assert.assertNotEquals;
+import static org.junit.Assert.fail;
+
+/**
+ * @author lulf
+ * @since 5.21
+ */
+public class PayloadTest {
+
+    @Test
+    public void testUncompressedToCompressedWithoutCompressionInfo() {
+        String json = "{\"foo\":13}";
+        ConfigPayload configPayload = ConfigPayload.fromString(json);
+        Payload payload = Payload.from(configPayload);
+        assertThat(payload.getData().toString(), is(json));
+        payload = Payload.from(payload.getData(), CompressionInfo.create(CompressionType.UNCOMPRESSED, 0));
+        Payload compressed = payload.withCompression(CompressionType.LZ4);
+        Payload uncompressed = compressed.withCompression(CompressionType.UNCOMPRESSED);
+        assertThat(uncompressed.getData().toString(), is(json));
+        assertThat(compressed.toString(), is(json));
+        assertThat(uncompressed.toString(), is(json));
+    }
+
+    @Test
+    public void testEquals() {
+        final String foo1 = "foo 1";
+        final String foo2 = "foo 2";
+
+        Payload a = Payload.from(foo1);
+        Payload b = Payload.from(foo1);
+
+        Payload c = Payload.from(foo2);
+
+        Slime slime = new Slime();
+        slime.setString(foo1);
+        Payload d = Payload.from(new ConfigPayload(slime));
+
+        slime.setString(foo1);
+        Payload e = Payload.from(new ConfigPayload(slime));
+
+        slime.setString("foo 2");
+        Payload f = Payload.from(new ConfigPayload(slime));
+
+        Payload g = null;
+        Payload h = null;
+        Payload i = null;
+        Payload j = null;
+        try {
+            g = Payload.from(new Utf8Array(foo1.getBytes("UTF-8")), CompressionInfo.uncompressed());
+            h = Payload.from(new Utf8Array(foo1.getBytes("UTF-8")), CompressionInfo.uncompressed());
+
+            LZ4PayloadCompressor compressor = new LZ4PayloadCompressor();
+            CompressionInfo info = CompressionInfo.create(CompressionType.LZ4, foo2.length());
+            Utf8Array compressed = new Utf8Array(compressor.compress(foo2.getBytes()));
+
+            i = Payload.from(compressed, info);
+            j = Payload.from(compressed, info);
+        } catch (UnsupportedEncodingException e1) {
+            fail();
+        }
+
+        new EqualsTester()
+                .addEqualityGroup(a, b, g, h)
+                .addEqualityGroup(c)
+                .addEqualityGroup(d, e)
+                .addEqualityGroup(f)
+                .addEqualityGroup(i, j).
+                testEquals();
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/protocol/SlimeTraceSerializerTest.java b/config/src/test/java/com/yahoo/vespa/config/protocol/SlimeTraceSerializerTest.java
new file mode 100644
index 00000000000..4c69fa3e395
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/protocol/SlimeTraceSerializerTest.java
@@ -0,0 +1,123 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.slime.JsonFormat;
+import com.yahoo.slime.Slime;
+import com.yahoo.text.Utf8;
+import com.yahoo.yolean.trace.TraceNode;
+import org.junit.Test;
+
+import java.io.ByteArrayOutputStream;
+import java.io.IOException;
+import java.util.ArrayList;
+import java.util.HashMap;
+import java.util.Iterator;
+import java.util.Map;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author lulf
+ * @since 5.5
+ */
+public class SlimeTraceSerializerTest {
+    @Test
+    public void test_serializer() throws IOException {
+        TraceNode root = new TraceNode(null, 1);
+        root.add(new TraceNode("foo", 4));
+        root.add(new TraceNode("bar", 5).add(new TraceNode("baz", 2).add(new TraceNode("quux", 10))));
+        assertThat(toJson(root), is("{\"timestamp\":1,\"children\":[{\"timestamp\":5,\"payload\":\"bar\",\"children\":[{\"timestamp\":2,\"payload\":\"baz\",\"children\":[{\"timestamp\":10,\"payload\":\"quux\"}]}]},{\"timestamp\":4,\"payload\":\"foo\"}]}"));
+        assertSerialize(root);
+    }
+
+    private String toJson(TraceNode root) throws IOException {
+        Slime slime = new Slime();
+        SlimeTraceSerializer serializer = new SlimeTraceSerializer(slime.setObject());
+        root.accept(serializer);
+        JsonFormat format = new JsonFormat(true);
+        ByteArrayOutputStream baos = new ByteArrayOutputStream();
+        format.encode(baos, slime);
+        return Utf8.toString(baos.toByteArray());
+    }
+
+    private void assertSerialize(TraceNode root) {
+        Slime slime = new Slime();
+        SlimeTraceSerializer serializer = new SlimeTraceSerializer(slime.setObject());
+        root.accept(serializer);
+        SlimeTraceDeserializer deserializer = new SlimeTraceDeserializer(slime.get());
+        TraceNode deser = deserializer.deserialize();
+        assertTraceEqual(deser, root);
+    }
+
+    private void assertTraceEqual(TraceNode deser, TraceNode root) {
+        assertThat(deser.timestamp(), is(root.timestamp()));
+        assertThat(deser.payload(), is(root.payload()));
+        Iterator<TraceNode> actualIt = deser.children().iterator();
+        Iterator<TraceNode> expectedIt = root.children().iterator();
+        Map<Long, TraceNode> expectedMapping = new HashMap<>();
+        Map<Long, TraceNode> actualMapping = new HashMap<>();
+        while (expectedIt.hasNext()) {
+            assertTrue(actualIt.hasNext());
+            TraceNode actualNode = actualIt.next();
+            TraceNode expectedNode = expectedIt.next();
+            expectedMapping.put(expectedNode.timestamp(), expectedNode);
+            actualMapping.put(actualNode.timestamp(), actualNode);
+        }
+        assertFalse(expectedIt.hasNext());
+        assertFalse(actualIt.hasNext());
+        for (long timestamp : expectedMapping.keySet()) {
+            assertTraceEqual(actualMapping.get(timestamp), expectedMapping.get(timestamp));
+        }
+    }
+
+    @Test
+    public void test_long() throws IOException {
+        TraceNode root = new TraceNode(14l, 5);
+        assertThat(toJson(root), is("{\"timestamp\":5,\"payload\":14}"));
+        assertSerialize(root);
+    }
+
+    @Test
+    public void test_double() throws IOException {
+        TraceNode root = new TraceNode(3.5, 5);
+        assertThat(toJson(root), is("{\"timestamp\":5,\"payload\":3.5}"));
+        assertSerialize(root);
+    }
+
+    @Test
+    public void test_bool() throws IOException {
+        TraceNode root = new TraceNode(true, 5);
+        assertThat(toJson(root), is("{\"timestamp\":5,\"payload\":true}"));
+        assertSerialize(root);
+    }
+
+    @Test
+    public void test_string() throws IOException {
+        TraceNode root = new TraceNode("bar", 5);
+        assertThat(toJson(root), is("{\"timestamp\":5,\"payload\":\"bar\"}"));
+        assertSerialize(root);
+    }
+
+    @Test
+    public void test_unknown() throws IOException {
+        TraceNode root = new TraceNode(new ArrayList<String>(), 5);
+        assertThat(toJson(root), is("{\"timestamp\":5}"));
+    }
+
+    @Test
+    public void test_null() throws IOException {
+        TraceNode root = new TraceNode(null, 5);
+        assertThat(toJson(root), is("{\"timestamp\":5}"));
+        assertSerialize(root);
+    }
+
+    @Test
+    public void test_bytearray() throws IOException {
+        TraceNode root = new TraceNode(new byte[] { 3, 5 }, 5);
+        assertThat(toJson(root), is("{\"timestamp\":5,\"payload\":\"0x0305\"}"));
+        assertSerialize(root);
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/protocol/TraceTest.java b/config/src/test/java/com/yahoo/vespa/config/protocol/TraceTest.java
new file mode 100644
index 00000000000..3e9d0650ae5
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/protocol/TraceTest.java
@@ -0,0 +1,61 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.protocol;
+
+import com.yahoo.slime.Slime;
+import org.junit.Test;
+
+import static org.junit.Assert.assertFalse;
+import static org.junit.Assert.assertTrue;
+
+/**
+ * @author lulf
+ * @since 5.3
+ */
+public class TraceTest {
+
+    @Test
+    public void trace_level_limits_tracing() {
+        Trace trace = Trace.createNew(3);
+        assertTrue(trace.shouldTrace(0));
+        assertTrue(trace.shouldTrace(1));
+        assertTrue(trace.shouldTrace(2));
+        assertTrue(trace.shouldTrace(3));
+        assertFalse(trace.shouldTrace(4));
+        assertFalse(trace.shouldTrace(5));
+        trace.trace(1, "foo");
+        trace.trace(1, "foo2");
+        trace.trace(2, "bar");
+        trace.trace(3, "baz");
+        trace.trace(3, "baz2");
+        trace.trace(4, "quux");
+        trace.trace(5, "quux2");
+        String str = trace.toString();
+        assertTrue(str.contains("foo"));
+        assertTrue(str.contains("foo2"));
+        assertTrue(str.contains("bar"));
+        assertTrue(str.contains("baz"));
+        assertTrue(str.contains("baz2"));
+        assertFalse(str.contains("quux"));
+        assertFalse(str.contains("quux2"));
+    }
+
+    @Test
+    public void trace_serialization() {
+        Trace trace = Trace.createNew(1);
+        trace.trace(0, "foobar");
+        trace.trace(1, "barbaz");
+        Slime slime = new Slime();
+        trace.serialize(slime.setObject());
+        Trace trace2 = Trace.fromSlime(slime.get());
+        trace2.trace(1, "quux");
+        String trace1Str = trace.toString();
+        String trace2Str = trace2.toString();
+        assertTrue(trace1Str.contains("foobar"));
+        assertTrue(trace1Str.contains("barbaz"));
+        assertFalse(trace1Str.contains("quux"));
+
+        assertTrue(trace2Str.contains("foobar"));
+        assertTrue(trace2Str.contains("barbaz"));
+        assertTrue(trace2Str.contains("quux"));
+    }
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/util/ConfigUtilsTest.java b/config/src/test/java/com/yahoo/vespa/config/util/ConfigUtilsTest.java
new file mode 100644
index 00000000000..d07c007c13f
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/util/ConfigUtilsTest.java
@@ -0,0 +1,288 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.vespa.config.util;
+
+import com.yahoo.collections.Tuple2;
+import com.yahoo.foo.SimpletypesConfig;
+import com.yahoo.io.IOUtils;
+import com.yahoo.vespa.config.ConfigDefinitionKey;
+import com.yahoo.vespa.config.ConfigPayload;
+import org.junit.Test;
+
+import java.io.File;
+import java.io.IOException;
+import java.io.StringReader;
+import java.util.ArrayList;
+import java.util.List;
+
+import static org.hamcrest.CoreMatchers.is;
+import static org.hamcrest.CoreMatchers.not;
+import static org.junit.Assert.assertThat;
+import static org.junit.Assert.fail;
+
+/**
+ * Tests ConfigUtils.
+ *
+ * @author <a href="musum@yahoo-inc.com">Harald Musum</a>
+ */
+public class ConfigUtilsTest {
+
+    @Test
+    public void testGetDefMd5() {
+        String expectedMd5 = "a29038b17c727dabc572a967a508dc1f";
+        List<String> lines = new ArrayList<>();
+
+        // Create normalized lines
+        lines.add("a");
+        lines.add("foo=1 # a comment");
+        lines.add("int a default=1 range = [,]");
+        lines.add(""); //empty line should not affect md5sum
+        lines.add("double b default=1.0 range = [,]");
+        lines.add("collectiontype      enum { SINGLE, ARRAY, WEIGHTEDSET } default=SINGLE");
+
+        assertThat(ConfigUtils.getDefMd5(lines), is(expectedMd5));
+
+        lines.clear();
+
+        // Test various normalizing features implemented by getMd5
+
+        // Check that lines are trimmed
+        lines.add("a ");
+        // Check that trailing comments are trimmed
+        lines.add("foo=1");
+        // Check that upper and lower bounds for int and double ranges are set correctly
+        lines.add("int a default=1 range = [-2147483648,2147483647]");
+        lines.add("double b default=1.0 range = [-100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000," +
+                "100000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000000]");
+        // check that space before commas are treated correctly
+        lines.add("collectiontype      enum { SINGLE , ARRAY , WEIGHTEDSET } default=SINGLE");
+        assertThat(ConfigUtils.getDefMd5(lines), is(expectedMd5));
+    }
+
+    @Test
+    public void testGetMd5WithComment() {
+        String expectedMd5 = "4395db1dfbd977c4d74190d2d23396e2";
+        List<String> lines = new ArrayList<>();
+
+        // Create normalized lines
+        lines.add("foo=\"1#hello\"");
+        lines.add(""); //empty line should not affect md5sum
+
+        assertThat(ConfigUtils.getMd5(lines), is(expectedMd5));
+
+        lines.clear();
+
+        // Check that comment character in string leads to a different md5 than the original
+        lines.add("foo=\"1#hello and some more\"");
+        String md5 = ConfigUtils.getMd5(lines);
+        assertThat(md5, is(not(expectedMd5)));
+
+        // Check that added characters aft comment character in string leads to a different md5 than above
+        lines.add("foo=\"1#hello and some more and even more\"");
+        assertThat(ConfigUtils.getMd5(lines), is(not(md5)));
+    }
+
+    @Test
+    public void testGetMd5OfPayload() {
+        String expectedMd5 = "c9246ed8c8ab55b1c463c501c84075e6";
+        String expectedChangedMd5 = "f6f81062ef5f024f1912798490ba7dfc";
+        ConfigPayload payload = ConfigPayload.fromInstance(new SimpletypesConfig(new SimpletypesConfig.Builder()));
+        System.out.println(payload);
+        assertThat(ConfigUtils.getMd5(payload), is(expectedMd5));
+        payload.getSlime().get().setString("fabio", "bar");
+        System.out.println(payload);
+        assertThat(ConfigUtils.getMd5(payload), is(expectedChangedMd5));
+    }
+
+    @Test
+    public void testGetMd5OfString() {
+        String expectedMd5 = "c9246ed8c8ab55b1c463c501c84075e6";
+        String expectedChangedMd5 = "f6f81062ef5f024f1912798490ba7dfc";
+        ConfigPayload payload = ConfigPayload.fromInstance(new SimpletypesConfig(new SimpletypesConfig.Builder()));
+        System.out.println(payload);
+        assertThat(ConfigUtils.getMd5(payload.toString(true)), is(expectedMd5));
+        payload.getSlime().get().setString("fabio", "bar");
+        System.out.println(payload);
+        assertThat(ConfigUtils.getMd5(payload.toString(true)), is(expectedChangedMd5));
+    }
+
+    @Test
+    public void testStripSpaces() {
+        assertThat(ConfigUtils.stripSpaces("a   b"), is("a b"));
+        assertThat(ConfigUtils.stripSpaces("\"a   b\""), is("\"a   b\""));
+        assertThat(ConfigUtils.stripSpaces("a   b   \"a   b\""), is("a b \"a   b\""));
+        assertThat(ConfigUtils.stripSpaces("a b"), is("a b"));
+    }
+
+    @Test
+    public void testGetVersion() {
+        StringReader reader = new StringReader("version=1\nint a default=0");
+        assertThat(ConfigUtils.getDefVersion(reader), is("1"));
+
+        // no version
+        reader = new StringReader("int a default=0");
+        assertThat(ConfigUtils.getDefVersion(reader), is(""));
+
+        // namespace and version
+        reader = new StringReader("version=1\nnamespace=foo\nint a default=0");
+        assertThat(ConfigUtils.getDefVersion(reader), is("1"));
+        reader = new StringReader("namespace=foo\nversion=1\nint a default=0");
+        assertThat(ConfigUtils.getDefVersion(reader), is("1"));
+    }
+
+    @Test
+    public void testGetNamespace() {
+        StringReader reader = new StringReader("version=1\nnamespace=a\nint a default=0");
+        assertThat(ConfigUtils.getDefNamespace(reader), is("a"));
+        // namespace first
+        reader = new StringReader("namespace=a\nversion=1\nint a default=0");
+        assertThat(ConfigUtils.getDefNamespace(reader), is("a"));
+
+        // No namespace
+        reader = new StringReader("version=1\nint a default=0");
+        assertThat(ConfigUtils.getDefNamespace(reader), is(""));
+
+        // comment lines
+        reader = new StringReader("#comment\nversion=1\n#comment2\nint a default=0");
+        assertThat(ConfigUtils.getDefNamespace(reader), is(""));
+
+        try {
+            ConfigUtils.getDefNamespace(null);
+            fail();
+        } catch (IllegalArgumentException e) {
+            //
+        }
+    }
+
+    @Test
+    public void testGetNameCommaVersion() {
+        String nameCommaversion = "foo,1";
+        Tuple2<String, String> tuple = ConfigUtils.getNameAndVersionFromString(nameCommaversion);
+        assertThat(tuple.first, is("foo"));
+        assertThat(tuple.second, is("1"));
+
+        // no version
+        nameCommaversion = "foo";
+        tuple = ConfigUtils.getNameAndVersionFromString(nameCommaversion);
+        assertThat(tuple.first, is("foo"));
+        assertThat(tuple.second, is(""));
+
+        // no name
+        nameCommaversion = ",1";
+        tuple = ConfigUtils.getNameAndVersionFromString(nameCommaversion);
+        assertThat(tuple.first, is(""));
+        assertThat(tuple.second, is("1"));
+    }
+
+    @Test
+    public void testNamespaceDotNames() {
+        String namespaceDotName = "foo.bar";
+        Tuple2<String, String> tuple = ConfigUtils.getNameAndNamespaceFromString(namespaceDotName);
+        assertThat(tuple.first, is("bar"));
+        assertThat(tuple.second, is("foo"));
+
+        namespaceDotName = "foo.baz.bar";
+        tuple = ConfigUtils.getNameAndNamespaceFromString(namespaceDotName);
+        assertThat(tuple.first, is("bar"));
+        assertThat(tuple.second, is("foo.baz"));
+
+        // no namespace
+        namespaceDotName = "bar";
+        tuple = ConfigUtils.getNameAndNamespaceFromString(namespaceDotName);
+        assertThat(tuple.first, is("bar"));
+        assertThat(tuple.second, is(""));
+
+        // no name
+        namespaceDotName = "foo.";
+        tuple = ConfigUtils.getNameAndNamespaceFromString(namespaceDotName);
+        assertThat(tuple.first, is(""));
+        assertThat(tuple.second, is("foo"));
+
+        // no namespace
+        namespaceDotName = ".bar";
+        tuple = ConfigUtils.getNameAndNamespaceFromString(namespaceDotName);
+        assertThat(tuple.first, is("bar"));
+        assertThat(tuple.second, is(""));
+    }
+
+    @Test
+    public void testGetConfigDefinitionKey() {
+        String input = "foo";
+        ConfigDefinitionKey def = ConfigUtils.getConfigDefinitionKeyFromString(input);
+        assertThat(def.getName(), is("foo"));
+        assertThat(def.getNamespace(), is(""));
+
+        input = "foo.bar";
+        def = ConfigUtils.getConfigDefinitionKeyFromString(input);
+        assertThat(def.getName(), is("bar"));
+        assertThat(def.getNamespace(), is("foo"));
+
+        input = "foo.bar.1";
+        def = ConfigUtils.getConfigDefinitionKeyFromString(input);
+        assertThat(def.getName(), is("bar"));
+        assertThat(def.getNamespace(), is("foo"));
+
+        input = "foo.bar.qux.2";
+        def = ConfigUtils.getConfigDefinitionKeyFromString(input);
+        assertThat(def.getName(), is("qux"));
+        assertThat(def.getNamespace(), is("foo.bar"));
+
+        input = "foo.2";
+        def = ConfigUtils.getConfigDefinitionKeyFromString(input);
+        assertThat(def.getName(), is("foo"));
+        assertThat(def.getNamespace(), is(""));
+    }
+
+    @Test
+    public void testCreateConfigDefinitionKeyFromZKString() {
+        String input = "foo,1";
+        ConfigDefinitionKey def = ConfigUtils.createConfigDefinitionKeyFromZKString(input);
+        assertThat(def.getName(), is("foo"));
+        assertThat(def.getNamespace(), is(""));
+
+        input = "bar.foo,1";
+        def = ConfigUtils.createConfigDefinitionKeyFromZKString(input);
+        assertThat(def.getName(), is("foo"));
+        assertThat(def.getNamespace(), is("bar"));
+    }
+
+    @Test
+    public void testCreateConfigDefinitionKeyFromDefFile() {
+        ConfigDefinitionKey def = null;
+        try {
+            def = ConfigUtils.createConfigDefinitionKeyFromDefFile(new File("src/test/resources/configs/def-files/app.def"));
+        } catch (IOException e) {
+            e.printStackTrace();
+            fail();
+        }
+        assertThat(def.getName(), is("app"));
+        assertThat(def.getNamespace(), is("foo"));
+
+        try {
+            def = ConfigUtils.createConfigDefinitionKeyFromDefFile(new File("src/test/resources/configs/def-files/testnamespace.def"));
+        } catch (IOException e) {
+            e.printStackTrace();
+            fail();
+        }
+        assertThat(def.getName(), is("testnamespace"));
+        assertThat(def.getNamespace(), is("foo"));
+
+        try {
+            byte[] content = IOUtils.readFileBytes(new File("src/test/resources/configs/def-files/app.def"));
+            def = ConfigUtils.createConfigDefinitionKeyFromDefContent("app", content);
+        } catch (IOException e) {
+            fail();
+        }
+        assertThat(def.getName(), is("app"));
+        assertThat(def.getNamespace(), is("foo"));
+
+        try {
+            byte[] content = IOUtils.readFileBytes(new File("src/test/resources/configs/def-files-nogen/foo.bar.app.def"));
+            def = ConfigUtils.createConfigDefinitionKeyFromDefContent("app", content);
+        } catch (IOException e) {
+            fail();
+        }
+        assertThat(def.getName(), is("app"));
+        assertThat(def.getNamespace(), is("mynamespace"));
+    }
+
+}
diff --git a/config/src/test/java/com/yahoo/vespa/config/xml/whitespace-test.xml b/config/src/test/java/com/yahoo/vespa/config/xml/whitespace-test.xml
new file mode 100644
index 00000000000..6f63e405df8
--- /dev/null
+++ b/config/src/test/java/com/yahoo/vespa/config/xml/whitespace-test.xml
@@ -0,0 +1,6 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<!-- Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root. -->
+<config name="string">
+  <stringVal> This is a string
+  that contains different kinds of whitespace </stringVal>
+</config>
diff --git a/config/src/test/resources/configdefinitions/bar.def b/config/src/test/resources/configdefinitions/bar.def
new file mode 100644
index 00000000000..9293df5afd5
--- /dev/null
+++ b/config/src/test/resources/configdefinitions/bar.def
@@ -0,0 +1,4 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=config
+
+barValue string default="defaultBar"
diff --git a/config/src/test/resources/configdefinitions/baz.def b/config/src/test/resources/configdefinitions/baz.def
new file mode 100644
index 00000000000..a505df39830
--- /dev/null
+++ b/config/src/test/resources/configdefinitions/baz.def
@@ -0,0 +1,4 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=config
+
+bazValue string default="defaultBaz"
diff --git a/config/src/test/resources/configdefinitions/bootstrap.def b/config/src/test/resources/configdefinitions/bootstrap.def
new file mode 100644
index 00000000000..8cd61352a09
--- /dev/null
+++ b/config/src/test/resources/configdefinitions/bootstrap.def
@@ -0,0 +1,6 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=config
+
+component[].name string
+component[].configid string
+
diff --git a/config/src/test/resources/configdefinitions/foo.def b/config/src/test/resources/configdefinitions/foo.def
new file mode 100644
index 00000000000..ace1ed3676d
--- /dev/null
+++ b/config/src/test/resources/configdefinitions/foo.def
@@ -0,0 +1,7 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=config
+
+fooValue string
+fooArray[] int
+fooStruct[].innerStruct[].bar int
+fooMap{} int
diff --git a/config/src/test/resources/configdefinitions/foobar.def b/config/src/test/resources/configdefinitions/foobar.def
new file mode 100644
index 00000000000..427abfa8d5d
--- /dev/null
+++ b/config/src/test/resources/configdefinitions/foobar.def
@@ -0,0 +1,4 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=config
+
+fooBarValue string default="defaultFooBar"
diff --git a/config/src/test/resources/configdefinitions/foodefault.def b/config/src/test/resources/configdefinitions/foodefault.def
new file mode 100644
index 00000000000..06d84a092cf
--- /dev/null
+++ b/config/src/test/resources/configdefinitions/foodefault.def
@@ -0,0 +1,4 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=config
+
+fooValue string default = "per"
diff --git a/config/src/test/resources/configdefinitions/function-test.def b/config/src/test/resources/configdefinitions/function-test.def
new file mode 100644
index 00000000000..40047418eb0
--- /dev/null
+++ b/config/src/test/resources/configdefinitions/function-test.def
@@ -0,0 +1,74 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#
+# This def file should test most aspects of def files that makes a difference
+# for the autogenerated config classes. The goal is to trigger all blocks of
+# code in the code generators. This includes:
+#
+# - Use all legal special characters in the def file name, to ensure that those
+#   that needs to be replaced in type names are actually replaced.
+# - Use the same enum type twice to verify that we dont declare or define it
+#   twice.
+# - Use the same struct type twice for the same reason.
+# - Include arrays of primitives and structs.
+# - Include enum primitives and array of enums. Arrays of enums must be handled
+#   specially by the C++ code.
+# - Include enums both with and without default values.
+# - Include primitive string, numbers & doubles both with and without default
+#   values.
+# - Have an array within a struct, to verify that we correctly recurse.
+# - Reuse type name further within to ensure that this works.
+
+namespace=config
+
+# Some random bool without a default value. These comments exist to check
+ # that comment parsing works.
+bool_val bool
+ ## A bool with a default value set.
+bool_with_def bool default=false
+int_val int
+int_with_def int default=-545
+long_val long
+long_with_def long default=-50000000000
+double_val double
+double_with_def double default=-6.43
+# Another comment
+string_val string
+stringwithdef string default="foobar"
+enum_val enum { FOO, BAR, FOOBAR }
+enumwithdef enum { FOO2, BAR2, FOOBAR2 } default=BAR2
+onechoice enum { ONLYFOO } default=ONLYFOO
+refval reference
+refwithdef reference default=":parent:"
+fileVal file
+
+boolarr[] bool
+intarr[] int
+longarr[] long
+doublearr[] double
+stringarr[] string
+enumarr[] enum { ARRAY, VALUES }
+refarr[] reference
+fileArr[] file
+
+# A basic struct
+basicStruct.foo string default="basic"
+basicStruct.bar int
+basicStruct.intArr[] int
+
+# A struct of struct
+rootStruct.inner0.name string default="inner0"
+rootStruct.inner0.index int
+rootStruct.inner1.name string default="inner1"
+rootStruct.inner1.index int
+rootStruct.inner2.array[] int
+rootStruct.innerArr[].boolVal bool default=false
+rootStruct.innerArr[].stringVal string
+
+myarray[].intval int default=14
+myarray[].stringval[] string
+myarray[].enumval enum { INNER, ENUM, TYPE } default=TYPE
+myarray[].refval reference # Value in array without default
+myarray[].fileVal file
+myarray[].anotherarray[].foo int default=-4
+myarray[].myStruct.a int
+myarray[].myStruct.b int default=2
diff --git a/config/src/test/resources/configdefinitions/motd.def b/config/src/test/resources/configdefinitions/motd.def
new file mode 100644
index 00000000000..554ffa8fb28
--- /dev/null
+++ b/config/src/test/resources/configdefinitions/motd.def
@@ -0,0 +1,84 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#
+# This def file should test most aspects of def files that makes a difference
+# for the autogenerated config classes. The goal is to trigger all blocks of
+# code in the code generators. This includes:
+#
+# - Use all legal special characters in the def file name, to ensure that those
+#   that needs to be replaced in type names are actually replaced.
+# - Use the same enum type twice to verify that we dont declare or define it
+#   twice.
+# - Use the same struct type twice for the same reason.
+# - Include arrays of primitives and structs.
+# - Include enum primitives and array of enums. Arrays of enums must be handled
+#   specially by the C++ code.
+# - Include enums both with and without default values.
+# - Include primitive string, numbers & doubles both with and without default
+#   values.
+# - Have an array within a struct, to verify that we correctly recurse.
+# - Reuse type name further within to ensure that this works.
+
+namespace=config
+
+# Some random bool without a default value. These comments exist to check
+ # that comment parsing works.e
+boolVal bool
+ ## A bool with a default value set.
+bool_with_def bool default=false
+intVal int
+intWithDef int default=-545
+longVal long
+longWithDef long default=1234567890123
+doubleVal double
+double_with_def double default=-6.43
+# Another comment
+stringVal string
+stringwithdef string default="foobar"
+stringnulldef string default="null"
+enumVal enum { FOO, BAR, FOOBAR }
+enumwithdef enum { FOO2, BAR2, FOOBAR2 } default=BAR2
+refVal reference
+refwithdef reference default=":parent:"
+fileVal file
+
+boolarr[] bool
+intarr[] int
+longarr[] long
+doublearr[] double
+stringarr[] string
+enumarr[] enum { ARRAY, VALUES }
+refarr[] reference
+filearr[] file
+
+boolmap{} bool
+intmap{} int
+longmap{} long
+doublemap{} double
+stringmap{} string
+enummap{} enum { LOL1, LOL2 }
+refmap{} reference
+filemap{} file
+
+structmap{}.foo int
+mapmap{}.map{}.bar int
+
+# A basic struct
+basic_struct.foo string default="foo"
+basic_struct.bar int default=0
+
+# A struct of struct
+struct_of_struct.inner0.name string default="inner0"
+struct_of_struct.inner0.index int default=0
+struct_of_struct.inner1.name string default="inner1"
+struct_of_struct.inner1.index int default=1
+
+myArray[].intVal int default=14
+myArray[].stringVal[] string
+myArray[].enumVal enum { INNER, ENUM, TYPE } default=TYPE
+myArray[].refVal reference # Value in array without default
+myArray[].anotherArray[].foo int default=-4
+
+value string default="value"
+buffer int default=-1
+rhs string default="rhs"
+lines string default="lines"
diff --git a/config/src/test/resources/configdefinitions/my.def b/config/src/test/resources/configdefinitions/my.def
new file mode 100644
index 00000000000..8c6728fc63c
--- /dev/null
+++ b/config/src/test/resources/configdefinitions/my.def
@@ -0,0 +1,4 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=config
+
+myField string
diff --git a/config/src/test/resources/configs/bar/app.cfg b/config/src/test/resources/configs/bar/app.cfg
new file mode 100644
index 00000000000..8e4096805ea
--- /dev/null
+++ b/config/src/test/resources/configs/bar/app.cfg
@@ -0,0 +1,7 @@
+message "msg2"
+times 2
+a[4]
+a[0].name "a0"
+a[1].name "a1"
+a[2].name "a2"
+a[3].name "a3"
diff --git a/config/src/test/resources/configs/bar/string.cfg b/config/src/test/resources/configs/bar/string.cfg
new file mode 100644
index 00000000000..5cb1a496e0e
--- /dev/null
+++ b/config/src/test/resources/configs/bar/string.cfg
@@ -0,0 +1 @@
+stringVal "My mess"
diff --git a/config/src/test/resources/configs/baz/app.1.cfg.new b/config/src/test/resources/configs/baz/app.1.cfg.new
new file mode 100644
index 00000000000..b734dd17297
--- /dev/null
+++ b/config/src/test/resources/configs/baz/app.1.cfg.new
@@ -0,0 +1,85 @@
+times 3
+a[0]=1
+a[2]=1
+a[3]=1
+a[4]=1
+a[5]=1
+a[6]=1
+a[7]=1
+a[8]=1
+a[9]=1
+a[10]=1
+a[11]=1
+a[12]=1
+a[13]=1
+a[14]=1
+a[15]=1
+a[16]=1
+a[17]=1
+a[18]=1
+a[19]=1
+a[20]=1
+a[21]=1
+a[22]=1
+a[23]=1
+a[24]=1
+a[25]=1
+a[26]=1
+a[27]=1
+a[28]=1
+a[29]=1
+a[30]=1
+a[31]=1
+a[32]=1
+a[33]=1
+a[34]=1
+a[35]=1
+a[36]=1
+a[37]=1
+a[38]=1
+a[39]=1
+a[40]=1
+a[41]=1
+a[42]=1
+a[43]=1
+a[44]=1
+a[45]=1
+a[46]=1
+a[47]=1
+a[48]=1
+a[49]=1
+a[50]=1
+a[51]=1
+a[52]=1
+a[53]=1
+a[54]=1
+a[55]=1
+a[56]=1
+a[57]=1
+a[58]=1
+a[59]=1
+a[60]=1
+a[61]=1
+a[62]=1
+a[63]=1
+a[64]=1
+a[65]=1
+a[66]=1
+a[67]=1
+a[68]=1
+a[69]=1
+version 1
+version 1
+version 1
+version 1
+version 1
+version 1
+version 1
+version 1
+version 1
+version 1
+version 1
+version 1
+version 1
+version 1
+version 2
diff --git a/config/src/test/resources/configs/baz/app.cfg b/config/src/test/resources/configs/baz/app.cfg
new file mode 100644
index 00000000000..b04f16fe7c9
--- /dev/null
+++ b/config/src/test/resources/configs/baz/app.cfg
@@ -0,0 +1,5 @@
+times 3
+a[3]
+a[0].name "a0"
+a[1].name "a1"
+a[2].name "a2"
diff --git a/config/src/test/resources/configs/datastructures/config1.txt b/config/src/test/resources/configs/datastructures/config1.txt
new file mode 100644
index 00000000000..f6121cfa486
--- /dev/null
+++ b/config/src/test/resources/configs/datastructures/config1.txt
@@ -0,0 +1,17 @@
+date[3]
+date[0] 14-Apr-08
+date[1] 15-Apr-08
+date[2] 16-Apr-08
+stock[2]
+stock[0].ticker YHOO
+stock[0].type COMMON
+stock[0].volume[3]
+stock[0].volume[0] 1333000
+stock[0].volume[1] 996000
+stock[0].volume[2] 2400000
+stock[1].ticker EWJ
+stock[1].type ETF
+stock[1].volume[3]
+stock[1].volume[0] 4600000
+stock[1].volume[1] 3002000
+stock[1].volume[2] 10987000
diff --git a/config/src/test/resources/configs/datastructures/config1_1.txt b/config/src/test/resources/configs/datastructures/config1_1.txt
new file mode 100644
index 00000000000..33a6d6c22aa
--- /dev/null
+++ b/config/src/test/resources/configs/datastructures/config1_1.txt
@@ -0,0 +1,14 @@
+date[2]
+date[0] 16-Apr-08
+date[1] 17-Apr-08
+stock[2]
+stock[0].ticker YHOO
+stock[0].type COMMON
+stock[0].volume[2]
+stock[0].volume[0] 1333000
+stock[0].volume[1] 800800
+stock[1].ticker JNJ
+stock[1].type COMMON
+stock[1].volume[2]
+stock[1].volume[0] 10987000
+stock[1].volume[1] 1300000
diff --git a/config/src/test/resources/configs/datastructures/config2.txt b/config/src/test/resources/configs/datastructures/config2.txt
new file mode 100644
index 00000000000..6cc31add025
--- /dev/null
+++ b/config/src/test/resources/configs/datastructures/config2.txt
@@ -0,0 +1,19 @@
+date[3]
+date[0] 14-Apr-08
+date[1] 15-Apr-08
+date[2] 16-Apr-08
+stock[2]
+stock[0].ticker YHOO
+stock[0].type COMMON
+stock[0].volume[3]
+stock[0].volume[0] 1333000
+stock[0].volume[1] 996000
+stock[0].volume[2] 2400000
+stock[1].ticker EWJ
+stock[1].type ETF
+stock[1].volume[3]
+stock[1].volume[0] 4600000
+stock[1].volume[1] 3002000
+stock[1].volume[2] 10987000
+basicstruct.foo "bar"
+basicstruct.bar 42
diff --git a/config/src/test/resources/configs/def-files-nogen/foo.bar.app.def b/config/src/test/resources/configs/def-files-nogen/foo.bar.app.def
new file mode 100644
index 00000000000..d2a1df70e7a
--- /dev/null
+++ b/config/src/test/resources/configs/def-files-nogen/foo.bar.app.def
@@ -0,0 +1,8 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=mynamespace
+
+message string default="Hello!"
+
+times int default=1
+
+a[].name string
diff --git a/config/src/test/resources/configs/def-files/app.def b/config/src/test/resources/configs/def-files/app.def
new file mode 100644
index 00000000000..30919c866e7
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/app.def
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=foo
+version=1
+
+message string default="Hello!"
+
+times int default=1
+
+a[].name string
diff --git a/config/src/test/resources/configs/def-files/arraytypes.def b/config/src/test/resources/configs/def-files/arraytypes.def
new file mode 100644
index 00000000000..b6e206ff925
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/arraytypes.def
@@ -0,0 +1,12 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+# Config containing only simple array types that can be used for testing
+# individual types in detail.
+namespace=foo
+version=1
+
+boolarr[] bool
+doublearr[] double
+enumarr[] enum { VAL1, VAL2 }
+intarr[] int
+longarr[] long
+stringarr[] string
diff --git a/config/src/test/resources/configs/def-files/chains-test.def b/config/src/test/resources/configs/def-files/chains-test.def
new file mode 100644
index 00000000000..26a23ff17da
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/chains-test.def
@@ -0,0 +1,43 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+# Chains configuration
+namespace=foo
+version=12
+
+component[].id string
+
+# Configured functionality provided by this - comes in addition to those set in the code
+component[].dependencies.provides[] string
+
+# Configured "before" dependencies provided by this - comes in addition to those set in the code
+component[].dependencies.before[] string
+
+# Configured "after" dependencies provided by this - comes in addition to those set in the code
+component[].dependencies.after[] string
+
+# The id of this chain. The id has the form name(:version)?
+# where the version has the form 1(.2(.3(.identifier)?)?)?.
+# The default chain must be called "default".
+chain[].id string
+
+#The type of this chain
+chain[].type enum {DOCPROC, SEARCH} default=SEARCH
+
+# The id of a component to include in this chain.
+# The id has the form fullclassname(:version)?
+# where the version has the form 1(.2(.3(.identifier)?)?)?.
+chain[].component[] string
+
+# The optional list of chain ids this inherits.
+# The ids has the form name(:version)?
+# where the version has the form 1(.2(.3(.identifier)?)?)?.
+# If the version is not specified the newest version is used.
+chain[].inherit[] string
+
+# The optional list of component ids to exclude from this chain even if they exists in inherited chains
+# If versions are specified in these ids, they are ignored.
+chain[].exclude[] string
+
+# The phases for a chain
+chain[].phase[].id string
+chain[].phase[].before[] string
+chain[].phase[].after[] string
diff --git a/config/src/test/resources/configs/def-files/datastructures.def b/config/src/test/resources/configs/def-files/datastructures.def
new file mode 100644
index 00000000000..803931c91bc
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/datastructures.def
@@ -0,0 +1,12 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=foo
+version=4
+
+date[] string
+
+stock[].ticker string
+stock[].type enum { COMMON, ETF, ETC } default=COMMON
+stock[].volume[] int
+
+basicstruct.foo string default="foo"
+basicstruct.bar int default=0
diff --git a/config/src/test/resources/configs/def-files/defaulttest.def b/config/src/test/resources/configs/def-files/defaulttest.def
new file mode 100644
index 00000000000..3934a0e4d12
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/defaulttest.def
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=foo
+version=3
+
+nondefaultstring string
+defaultstring string default="thedefault"
+
+nondefaultreference reference
+defaultreference reference default="thedefault"
diff --git a/config/src/test/resources/configs/def-files/function-test.def b/config/src/test/resources/configs/def-files/function-test.def
new file mode 100644
index 00000000000..4529630c6b1
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/function-test.def
@@ -0,0 +1,89 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#
+# This def file should test most aspects of def files that makes a difference
+# for the autogenerated config classes. The goal is to trigger all blocks of
+# code in the code generators. This includes:
+#
+# - Use all legal special characters in the def file name, to ensure that those
+#   that needs to be replaced in type names are actually replaced.
+# - Use the same enum type twice to verify that we dont declare or define it
+#   twice.
+# - Use the same struct type twice for the same reason.
+# - Include arrays of primitives and structs.
+# - Include enum primitives and array of enums. Arrays of enums must be handled
+#   specially by the C++ code.
+# - Include enums both with and without default values.
+# - Include primitive string, numbers & doubles both with and without default
+#   values.
+# - Have an array within a struct, to verify that we correctly recurse.
+# - Reuse type name further within to ensure that this works.
+
+version=8
+
+namespace=foo
+
+# Some random bool without a default value. These comments exist to check
+ # that comment parsing works.
+bool_val bool
+ ## A bool with a default value set.
+bool_with_def bool default=false
+int_val int
+int_with_def int default=-545
+long_val long
+long_with_def long default=-50000000000
+double_val double
+double_with_def double default=-6.43
+# Another comment
+string_val string
+stringwithdef string default="foobar"
+enum_val enum { FOO, BAR, FOOBAR }
+enumwithdef enum { FOO2, BAR2, FOOBAR2 } default=BAR2
+onechoice enum { ONLYFOO } default=ONLYFOO
+refval reference
+refwithdef reference default=":parent:"
+fileVal file
+pathVal path
+
+boolarr[] bool
+intarr[] int
+longarr[] long
+doublearr[] double
+stringarr[] string
+enumarr[] enum { ARRAY, VALUES }
+refarr[] reference
+fileArr[] file
+pathArr[] path
+
+intMap{} int
+stringMap{} string
+filemap{} file
+pathMap{} path
+
+# A basic struct
+basicStruct.foo string default="basic"
+basicStruct.bar int
+basicStruct.intArr[] int
+
+# A struct of struct
+rootStruct.inner0.name string default="inner0"
+rootStruct.inner0.index int
+rootStruct.inner1.name string default="inner1"
+rootStruct.inner1.index int
+rootStruct.innerArr[].boolVal bool default=false
+rootStruct.innerArr[].stringVal string
+
+myarray[].intval int default=14
+myarray[].stringval[] string
+myarray[].enumval enum { INNER, ENUM, TYPE } default=TYPE
+myarray[].refval reference # Value in array without default
+myarray[].fileVal file
+myarray[].anotherarray[].foo int default=-4
+myarray[].myStruct.a int
+myarray[].myStruct.b int default=2
+
+myStructMap{}.myInt int
+myStructMap{}.myString string
+myStructMap{}.myIntDef int default=56
+myStructMap{}.myStringDef string default="g"
+myStructMap{}.anotherMap{}.anInt int
+myStructMap{}.anotherMap{}.anIntDef int default=11
diff --git a/config/src/test/resources/configs/def-files/int.def b/config/src/test/resources/configs/def-files/int.def
new file mode 100755
index 00000000000..fd07c90dfd5
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/int.def
@@ -0,0 +1,5 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=foo
+version=1
+
+intVal int default=1
diff --git a/config/src/test/resources/configs/def-files/maptypes.def b/config/src/test/resources/configs/def-files/maptypes.def
new file mode 100644
index 00000000000..389a9b71012
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/maptypes.def
@@ -0,0 +1,13 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+# Config containing only structs in various forms
+namespace=foo
+
+boolmap{} bool
+intmap{} int
+longmap{} long
+doublemap{} double
+stringmap{} string
+filemap{} file
+
+innermap{}.foo int
+nestedmap{}.inner{} int
diff --git a/config/src/test/resources/configs/def-files/md5test.def b/config/src/test/resources/configs/def-files/md5test.def
new file mode 100644
index 00000000000..f9fd7a645d2
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/md5test.def
@@ -0,0 +1,27 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=foo
+# version=4 , version in comment does not count.
+
+# Added empty line to see if we can confuse
+# the server's md5 calculation
+version=3
+
+#even adding a variable name starting with 'version'
+versiontag int default=3
+
+blabla string default=""
+tabs string default="		"
+test int
+
+# test multiple spaces/tabs
+spaces     int
+singletab	string
+multitabs			double
+
+# test enum
+normal enum { VAL1, VAL2 } default=VAL1
+spacevalues enum { V1  , V2 ,  V3  ,  V4 } default=V3  
+
+# Comments and empty lines at the end
+
+
diff --git a/config/src/test/resources/configs/def-files/namespace.def b/config/src/test/resources/configs/def-files/namespace.def
new file mode 100644
index 00000000000..429b835a6aa
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/namespace.def
@@ -0,0 +1,6 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+version=1
+
+namespace=myproject.config
+
+a int
diff --git a/config/src/test/resources/configs/def-files/simpletypes.def b/config/src/test/resources/configs/def-files/simpletypes.def
new file mode 100644
index 00000000000..e3954a92edc
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/simpletypes.def
@@ -0,0 +1,12 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=foo
+# Config containing only simple leaf types with default values, that can be used
+# for testing individual types in detail.
+version=1
+
+boolval bool default=false
+doubleval double default=0.0
+enumval enum { VAL1, VAL2 } default=VAL1
+intval int default=0
+longval long default=0
+stringval string default="s"
diff --git a/config/src/test/resources/configs/def-files/specialtypes.def b/config/src/test/resources/configs/def-files/specialtypes.def
new file mode 100644
index 00000000000..7b9b68d38a6
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/specialtypes.def
@@ -0,0 +1,4 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=foo
+myfile file
+myref reference
diff --git a/config/src/test/resources/configs/def-files/standard.def b/config/src/test/resources/configs/def-files/standard.def
new file mode 100644
index 00000000000..94e2e3133f4
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/standard.def
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+# Config containing only simple leaf types with default values, that can be used
+# for testing individual types in detail.
+namespace=foo
+version=1
+
+basicStruct.intVal int default=0
+basicStruct.stringVal string default="s"
+stringArr[] string
diff --git a/config/src/test/resources/configs/def-files/string.def b/config/src/test/resources/configs/def-files/string.def
new file mode 100755
index 00000000000..0605dc6e10c
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/string.def
@@ -0,0 +1,5 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace=foo
+version=1
+
+stringVal string default="_default_"
diff --git a/config/src/test/resources/configs/def-files/structtypes.def b/config/src/test/resources/configs/def-files/structtypes.def
new file mode 100644
index 00000000000..dfcec942799
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/structtypes.def
@@ -0,0 +1,22 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+# Config containing only structs in various forms
+namespace=foo
+version=2
+
+simple.name string default="_default_"
+simple.gender enum { MALE, FEMALE } default=MALE
+simple.emails[] string
+
+nested.inner.name string default="_default_"
+nested.inner.gender enum { MALE, FEMALE } default=MALE
+nested.inner.emails[] string
+
+simplearr[].name string
+simplearr[].gender enum { MALE, FEMALE }
+
+nestedarr[].inner.name string
+nestedarr[].inner.gender enum { MALE, FEMALE }
+nestedarr[].inner.emails[] string
+
+complexarr[].innerarr[].name string
+complexarr[].innerarr[].gender enum { MALE, FEMALE }
diff --git a/config/src/test/resources/configs/def-files/test-nodefs.def b/config/src/test/resources/configs/def-files/test-nodefs.def
new file mode 100644
index 00000000000..e35438a26ff
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/test-nodefs.def
@@ -0,0 +1,17 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+version=2
+namespace=foo
+
+# test config vars with no defaults
+
+s string
+j int
+b bool
+f double
+e enum { AA, BB, CC }
+
+basicstruct.foo string
+basicstruct.bar int
+
+arr[].s string
+arr[].i int
diff --git a/config/src/test/resources/configs/def-files/test-nonstring.def b/config/src/test/resources/configs/def-files/test-nonstring.def
new file mode 100644
index 00000000000..4819b32e1ba
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/test-nonstring.def
@@ -0,0 +1,10 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+version=1
+namespace=foo
+
+# Test non-string config vars with defaults
+
+i int default=0
+b bool default=false
+d double default=0.0
+e enum { AA, BB, CC } default=AA
diff --git a/config/src/test/resources/configs/def-files/test-reference.def b/config/src/test/resources/configs/def-files/test-reference.def
new file mode 100644
index 00000000000..dacb9a18544
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/test-reference.def
@@ -0,0 +1,5 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+version=1
+namespace=foo
+
+configId reference default=":parent:"
diff --git a/config/src/test/resources/configs/def-files/testnamespace.def b/config/src/test/resources/configs/def-files/testnamespace.def
new file mode 100644
index 00000000000..56710807954
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/testnamespace.def
@@ -0,0 +1,4 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+version=1
+namespace=foo
+basicStruct.stringVal string
diff --git a/config/src/test/resources/configs/def-files/unicode.def b/config/src/test/resources/configs/def-files/unicode.def
new file mode 100644
index 00000000000..310564f4cfd
--- /dev/null
+++ b/config/src/test/resources/configs/def-files/unicode.def
@@ -0,0 +1,6 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+version=2
+namespace=foo
+
+unicodestring1 string
+unicodestring2 string default="abc æøå 囲碁 ÆØÅ ABC"
diff --git a/config/src/test/resources/configs/foo/app.cfg b/config/src/test/resources/configs/foo/app.cfg
new file mode 100644
index 00000000000..30426957db6
--- /dev/null
+++ b/config/src/test/resources/configs/foo/app.cfg
@@ -0,0 +1,6 @@
+message "msg1"
+times 3
+a[3]
+a[0].name "a0"
+a[1].name "a1"
+a[2].name "a2"
diff --git a/config/src/test/resources/configs/foo/test-reference.cfg b/config/src/test/resources/configs/foo/test-reference.cfg
new file mode 100644
index 00000000000..127d63f27dc
--- /dev/null
+++ b/config/src/test/resources/configs/foo/test-reference.cfg
@@ -0,0 +1 @@
+configId ":parent:"
diff --git a/config/src/test/resources/configs/function-test/defaultvalues.txt b/config/src/test/resources/configs/function-test/defaultvalues.txt
new file mode 100644
index 00000000000..14a7de7a9ed
--- /dev/null
+++ b/config/src/test/resources/configs/function-test/defaultvalues.txt
@@ -0,0 +1,47 @@
+bool_val false
+int_val 5
+long_val 1234567890123
+double_val 41.23
+string_val "foo"
+enum_val FOOBAR
+refval :parent:
+fileVal "vespa.log"
+pathVal "pom.xml"
+boolarr[1]
+boolarr[0] false
+intarr[0]
+longarr[0]
+doublearr[2]
+doublearr[0] 2344
+doublearr[1] 123
+stringarr[1]
+stringarr[0] "bar"
+enumarr[1]
+enumarr[0] VALUES
+refarr[0]
+fileArr[0]
+
+basicStruct.bar 3
+basicStruct.intArr[1]
+basicStruct.intArr[0] 10
+rootStruct.inner0.index 11
+rootStruct.inner1.index 12
+rootStruct.innerArr[1]
+rootStruct.innerArr[0].stringVal "deep"
+
+myarray[2]
+myarray[0].stringval[2]
+myarray[0].stringval[0] "baah"
+myarray[0].stringval[1] "yikes"
+myarray[0].refval ":parent:"
+myarray[0].fileVal "command.com"
+myarray[0].anotherarray[1]
+myarray[0].anotherarray[0].foo 7
+myarray[0].myStruct.a 1
+myarray[1].stringval[0]
+myarray[1].refval ":parent:"
+myarray[1].fileVal "display.sys"
+myarray[1].anotherarray[2]
+myarray[1].anotherarray[0].foo 1
+myarray[1].anotherarray[1].foo 2
+myarray[1].myStruct.a -1
diff --git a/config/src/test/resources/configs/function-test/defaultvalues.xml b/config/src/test/resources/configs/function-test/defaultvalues.xml
new file mode 100644
index 00000000000..80644c2fdb1
--- /dev/null
+++ b/config/src/test/resources/configs/function-test/defaultvalues.xml
@@ -0,0 +1,62 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<!-- Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root. -->
+<config name="function-test">
+  <bool_val>false</bool_val>
+  <int_val>5</int_val>
+  <long_val>1234567890123</long_val>
+  <double_val>41.23</double_val>
+  <string_val>foo</string_val>
+  <enum_val>FOOBAR</enum_val>
+  <refval>:parent:</refval>
+  <fileVal>vespa.log</fileVal>
+
+  <boolarr index="0">false</boolarr>
+  <doublearr index="0">2344</doublearr>
+  <doublearr index="1">123</doublearr>
+  <stringarr index="0">bar</stringarr>
+  <enumarr index="0">VALUES</enumarr>
+
+  <basicStruct>
+    <bar>3</bar>
+    <intArr index="0">10</intArr>
+  </basicStruct>
+
+  <rootStruct>
+    <inner0>
+      <index>11</index>
+    </inner0>
+    <inner1>
+      <index>12</index>
+    </inner1>
+    <innerArr index="0">
+      <stringVal>deep</stringVal>
+    </innerArr>
+  </rootStruct>
+
+  <myarray index="0">
+    <stringval index="0">baah</stringval>
+    <stringval index="1">yikes</stringval>
+    <refval>:parent:</refval>
+    <fileVal>command.com</fileVal>
+    <anotherarray index="0">
+      <foo>7</foo>
+    </anotherarray>
+    <myStruct>
+      <a>1</a>
+    </myStruct>
+  </myarray>
+  <myarray index="1">
+    <refval>:parent:</refval>
+    <fileVal>display.sys</fileVal>
+    <anotherarray index="0">
+      <foo>1</foo>
+    </anotherarray>
+    <anotherarray index="1">
+      <foo>2</foo>
+    </anotherarray>
+    <myStruct>
+      <a>-1</a>
+    </myStruct>
+  </myarray>
+
+</config>
diff --git a/config/src/test/resources/configs/function-test/missingvalue.txt b/config/src/test/resources/configs/function-test/missingvalue.txt
new file mode 100644
index 00000000000..9616ac3d27b
--- /dev/null
+++ b/config/src/test/resources/configs/function-test/missingvalue.txt
@@ -0,0 +1,39 @@
+bool_val false
+long_val 123
+double_val 41.23
+string_val "foo"
+enum_val FOOBAR
+refval ":parent:"
+fileVal "msdos.sys"
+boolarr[1]
+boolarr[0] false
+intarr[0]
+longarr[0]
+doublearr[2]
+doublearr[0] 2344
+doublearr[1] 123
+stringarr[1]
+stringarr[0] "bar"
+enumarr[1]
+enumarr[0] VALUES
+refarr[0]
+basicStruct.bar 3
+rootStruct.inner0.index 11
+rootStruct.inner1.index 12
+rootStruct.innerArr[0]
+myarray[2]
+myarray[0].stringval[2]
+myarray[0].stringval[0] "baah"
+myarray[0].stringval[1] "yikes"
+myarray[0].refval ":parent:"
+myarray[0].fileVal "command.com"
+myarray[0].anotherarray[1]
+myarray[0].anotherarray[0].foo 7
+myarray[0].myStruct.a 1
+myarray[1].stringval[0]
+myarray[1].refval ":parent:"
+myarray[1].fileVal "display.sys"
+myarray[1].anotherarray[2]
+myarray[1].anotherarray[0].foo 1
+myarray[1].anotherarray[1].foo 2
+myarray[1].myStruct.a 1
diff --git a/config/src/test/resources/configs/function-test/randomorder.txt b/config/src/test/resources/configs/function-test/randomorder.txt
new file mode 100644
index 00000000000..bd91c24f3fb
--- /dev/null
+++ b/config/src/test/resources/configs/function-test/randomorder.txt
@@ -0,0 +1,56 @@
+boolarr[1]
+boolarr[0] false
+int_with_def -14
+double_val 41.23
+double_with_def -12
+enumwithdef BAR2
+refval ":parent:"
+refwithdef ":parent:"
+intarr[0]
+basicStruct.intArr[1]
+basicStruct.intArr[0] 10
+doublearr[2]
+doublearr[0] 2344
+doublearr[1] 123
+string_val "foo"
+stringwithdef "bar and foo"
+enum_val FOOBAR
+stringarr[1]
+stringarr[0] "bar"
+basicStruct.bar 3
+long_with_def -333000333000
+enumarr[1]
+enumarr[0] VALUES
+refarr[0]
+rootStruct.innerArr[1]
+rootStruct.innerArr[0].stringVal "deep"
+fileVal "autoexec.bat"
+myarray[2]
+myarray[0].intval -5
+myarray[0].myStruct.a 1
+myarray[0].enumval INNER
+myarray[0].refval ":parent:"
+myarray[0].anotherarray[1]
+myarray[0].anotherarray[0].foo 7
+myarray[0].stringval[2]
+myarray[0].stringval[0] "baah"
+myarray[0].stringval[1] "yikes"
+myarray[0].fileVal "file0"
+myarray[1].stringval[0]
+myarray[1].enumval INNER
+myarray[1].anotherarray[2]
+myarray[1].anotherarray[0].foo 1
+myarray[1].anotherarray[1].foo 2
+myarray[1].myStruct.a -1
+myarray[1].refval ":parent:"
+myarray[1].intval 5
+myarray[1].fileVal "file1"
+bool_val false
+bool_with_def true
+longarr[0]
+rootStruct.inner1.index 12
+int_val 5
+rootStruct.inner0.index 11
+long_val 666000666000
+fileArr[0]
+pathVal "pom.xml"
\ No newline at end of file
diff --git a/config/src/test/resources/configs/function-test/variableaccess.txt b/config/src/test/resources/configs/function-test/variableaccess.txt
new file mode 100644
index 00000000000..997de21750d
--- /dev/null
+++ b/config/src/test/resources/configs/function-test/variableaccess.txt
@@ -0,0 +1,85 @@
+pathMap{"one"} "pom.xml"
+bool_val false
+bool_with_def true
+int_val 5
+int_with_def -14
+long_val 12345678901
+long_with_def -9876543210
+double_val 41.23
+double_with_def -12
+string_val "foo"
+stringwithdef "bar and foo"
+enum_val FOOBAR
+enumwithdef BAR2
+refval :parent:
+refwithdef ":parent:"
+fileVal "etc"
+pathVal "pom.xml"
+boolarr[1]
+boolarr[0] false
+intarr[0]
+longarr[2]
+longarr[0] 9223372036854775807
+longarr[1] -9223372036854775808
+doublearr[2]
+doublearr[0] 2344
+doublearr[1] 123
+stringarr[1]
+stringarr[0] "bar"
+enumarr[1]
+enumarr[0] VALUES
+refarr[3]
+refarr[0] ":parent:"
+refarr[1] ":parent"
+refarr[2] "parent:"
+fileArr[1]
+fileArr[0] "bin"
+pathArr[1]
+pathArr[0] "pom.xml"
+
+intMap{"one"} 1
+intMap{"two"} 2
+stringMap{"one"} "first"
+
+basicStruct.foo "basicFoo"
+basicStruct.bar 3
+basicStruct.intArr[2]
+basicStruct.intArr[0] 310
+basicStruct.intArr[1] 311
+rootStruct.inner0.index 11
+rootStruct.inner1.index 12
+rootStruct.innerArr[2]
+rootStruct.innerArr[0].boolVal true
+rootStruct.innerArr[0].stringVal "deep"
+rootStruct.innerArr[1].boolVal false
+rootStruct.innerArr[1].stringVal "blue a=\"escaped\""
+
+myarray[2]
+myarray[0].intval -5
+myarray[0].stringval[2]
+myarray[0].stringval[0] "baah"
+myarray[0].stringval[1] "yikes"
+myarray[0].enumval INNER
+myarray[0].refval :parent:
+myarray[0].fileVal "file0"
+myarray[0].anotherarray[1]
+myarray[0].anotherarray[0].foo 7
+myarray[0].myStruct.a 1
+myarray[0].myStruct.b 2
+myarray[1].intval 5
+myarray[1].stringval[0]
+myarray[1].enumval INNER
+myarray[1].refval ":parent:"
+myarray[1].fileVal "file1"
+myarray[1].anotherarray[2]
+myarray[1].anotherarray[0].foo 1
+myarray[1].anotherarray[1].foo 2
+myarray[1].myStruct.a -1
+myarray[1].myStruct.b -2
+
+myStructMap{"one"}.myInt 1
+myStructMap{"one"}.myString "bull"
+myStructMap{"one"}.myIntDef 2
+myStructMap{"one"}.myStringDef "bear"
+myStructMap{"one"}.anotherMap{"anotherOne"}.anInt 3
+myStructMap{"one"}.anotherMap{"anotherOne"}.anIntDef 4
diff --git a/config/src/test/resources/configs/illegal/app.cfg b/config/src/test/resources/configs/illegal/app.cfg
new file mode 100644
index 00000000000..d22d3d46c90
--- /dev/null
+++ b/config/src/test/resources/configs/illegal/app.cfg
@@ -0,0 +1,6 @@
+message "msg1"
+times thisisnotanint
+a[3]
+a[0].name "a0"
+a[1].name "a1"
+a[2].name "a2"
diff --git a/config/src/test/resources/configs/unicode/unicode.cfg b/config/src/test/resources/configs/unicode/unicode.cfg
new file mode 100644
index 00000000000..d2c94abea86
--- /dev/null
+++ b/config/src/test/resources/configs/unicode/unicode.cfg
@@ -0,0 +1,2 @@
+unicodestring1 "Hei æøå 바둑 ÆØÅ hallo"
+unicodestring2 "abc æøå 囲碁 ÆØÅ ABC"
diff --git a/config/src/testlist.txt b/config/src/testlist.txt
new file mode 100644
index 00000000000..b002769217e
--- /dev/null
+++ b/config/src/testlist.txt
@@ -0,0 +1,25 @@
+tests/frtconnectionpool
+tests/raw_subscription
+tests/file_subscription
+tests/subscription
+tests/getconfig
+tests/configagent
+tests/misc
+tests/configholder
+tests/configfetcher
+tests/configmanager
+tests/subscriber
+tests/functiontest
+tests/legacysubscriber
+tests/print
+tests/configformat
+tests/configgen
+tests/configparser
+tests/configretriever
+tests/frt
+tests/unittest
+tests/api
+tests/failover
+tests/configuri
+tests/trace
+tests/payload_converter
diff --git a/config/src/testrun/.gitignore b/config/src/testrun/.gitignore
new file mode 100644
index 00000000000..faed45bc94a
--- /dev/null
+++ b/config/src/testrun/.gitignore
@@ -0,0 +1,10 @@
+test-report.html
+test-report.html.*
+test.*.*.desc
+test.*.*.file.*
+test.*.*.files.html
+test.*.*.log
+tmp.*
+xsync.log
+/test.*.*.result
+Makefile
diff --git a/config/src/tests/.gitignore b/config/src/tests/.gitignore
new file mode 100644
index 00000000000..a3e9c375723
--- /dev/null
+++ b/config/src/tests/.gitignore
@@ -0,0 +1,3 @@
+.depend
+Makefile
+*_test
diff --git a/config/src/tests/api/.gitignore b/config/src/tests/api/.gitignore
new file mode 100644
index 00000000000..67666db8b50
--- /dev/null
+++ b/config/src/tests/api/.gitignore
@@ -0,0 +1,3 @@
+/config-my.cpp
+/config-my.h
+config_api_test_app
diff --git a/config/src/tests/api/CMakeLists.txt b/config/src/tests/api/CMakeLists.txt
new file mode 100644
index 00000000000..93d12a5dc66
--- /dev/null
+++ b/config/src/tests/api/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_api_test_app
+    SOURCES
+    api.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_api_test_app COMMAND config_api_test_app)
+vespa_generate_config(config_api_test_app ../../test/resources/configdefinitions/my.def)
diff --git a/config/src/tests/api/api.cpp b/config/src/tests/api/api.cpp
new file mode 100644
index 00000000000..54042fcef1f
--- /dev/null
+++ b/config/src/tests/api/api.cpp
@@ -0,0 +1,45 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/config.h>
+#include <config-my.h>
+
+using namespace config;
+
+TEST("require that can subscribe with empty config id") {
+    ConfigSet set;
+    ConfigContext::SP ctx(new ConfigContext(set));
+    MyConfigBuilder builder;
+    builder.myField = "myfoo";
+    set.addBuilder("", &builder);
+    ConfigSubscriber subscriber(ctx);
+    ConfigHandle<MyConfig>::UP handle = subscriber.subscribe<MyConfig>("");
+    ASSERT_TRUE(subscriber.nextConfig(0));
+    std::unique_ptr<MyConfig> cfg(handle->getConfig());
+    ASSERT_TRUE(cfg.get() != NULL);
+    ASSERT_EQUAL("myfoo", cfg->myField);
+}
+
+/*
+ * TODO: Convert to frt test.
+TEST_MT_FFF("require that source may be unable to serve config temporarily", 2, ConfigContext::SP(new ConfigContext()),
+                                                                                 ConfigSet(),
+                                                                                 MyConfigBuilder()) {
+    if (thread_id == 0) {
+        ConfigSubscriber subscriber(f1, f2);
+        ConfigHandle<MyConfig>::UP handle = subscriber.subscribe<MyConfig>("myid", 10000);
+        ASSERT_TRUE(subscriber.nextConfig(10000));
+        std::unique_ptr<MyConfig> cfg(handle->getConfig());
+        ASSERT_TRUE(cfg.get() != NULL);
+        ASSERT_EQUAL("myfoo", cfg->myField);
+    } else {
+        FastOS_Thread::Sleep(1000);
+        f3.myField = "myfoo";
+        f2.addBuilder("myid", &f3);
+        f1->reload();
+
+    }
+}
+*/
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/configagent/.gitignore b/config/src/tests/configagent/.gitignore
new file mode 100644
index 00000000000..59a4f806257
--- /dev/null
+++ b/config/src/tests/configagent/.gitignore
@@ -0,0 +1,3 @@
+/config-my.cpp
+/config-my.h
+config_configagent_test_app
diff --git a/config/src/tests/configagent/CMakeLists.txt b/config/src/tests/configagent/CMakeLists.txt
new file mode 100644
index 00000000000..715e5260e30
--- /dev/null
+++ b/config/src/tests/configagent/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_configagent_test_app
+    SOURCES
+    configagent.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_configagent_test_app COMMAND config_configagent_test_app)
+vespa_generate_config(config_configagent_test_app ../../test/resources/configdefinitions/my.def)
diff --git a/config/src/tests/configagent/configagent.cpp b/config/src/tests/configagent/configagent.cpp
new file mode 100644
index 00000000000..73394d443a4
--- /dev/null
+++ b/config/src/tests/configagent/configagent.cpp
@@ -0,0 +1,294 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/config.h>
+#include <vespa/config/raw/rawsource.h>
+#include <vespa/config/common/misc.h>
+#include <vespa/config/common/configrequest.h>
+#include <vespa/config/common/timingvalues.h>
+#include <vespa/config/common/trace.h>
+#include <vespa/config/frt/frtconfigagent.h>
+#include <config-my.h>
+
+using namespace config;
+
+class MyConfigRequest : public ConfigRequest
+{
+public:
+    MyConfigRequest(const ConfigKey & key)
+        : _key(key)
+    { }
+
+    const ConfigKey & getKey() const
+    {
+        return _key;
+    }
+
+    bool abort()
+    {
+        return false;
+    }
+
+    bool isAborted() const
+    {
+        return false;
+    }
+
+    void setError(int errorCode)
+    {
+        (void) errorCode;
+    }
+    const ConfigKey _key;
+};
+
+class MyConfigResponse : public ConfigResponse
+{
+public:
+    MyConfigResponse(const ConfigKey & key, const ConfigValue & value, bool isUpdated, bool valid,
+                     int64_t timestamp, const vespalib::string & md5, const std::string & errorMsg, int errorC0de, bool iserror)
+        : _key(key),
+          _value(value),
+          _isUpdated(isUpdated),
+          _fillCalled(false),
+          _valid(valid),
+          _state(md5, timestamp),
+          _errorMessage(errorMsg),
+          _errorCode(errorC0de),
+          _isError(iserror)
+    { }
+
+    const ConfigKey& getKey() const
+    {
+        return _key;
+    }
+
+    const ConfigValue & getValue() const
+    {
+        return _value;
+    }
+
+    const ConfigState & getConfigState() const
+    {
+        return _state;
+    }
+
+    bool hasValidResponse() const
+    {
+        return _valid;
+    }
+
+    bool validateResponse()
+    {
+        return _valid;
+    }
+
+    void fill()
+    {
+        _fillCalled = true;
+    }
+
+    vespalib::string errorMessage() const
+    {
+        return _errorMessage;
+    }
+
+    int errorCode() const
+    {
+        return _errorCode;
+    }
+
+    bool isError() const
+    {
+        return  _isError;
+    }
+
+    const Trace & getTrace() const { return _trace; }
+
+    const ConfigKey _key;
+    const ConfigValue _value;
+    bool _isUpdated;
+    bool _fillCalled;
+    bool _valid;
+    const ConfigState _state;
+    vespalib::string _errorMessage;
+    int _errorCode;
+    bool _isError;
+    Trace _trace;
+
+
+/**
+    MyConfigResponse(const ConfigKey & key, const ConfigValue & value, bool isUpdated, bool valid,
+                     int64_t timestamp, const vespalib::string & md5, int64_t prevTimestamp, const vespalib::string &prevMd5,
+                     const std::string & errorMsg, int errorC0de, bool iserror)
+*/
+    static ConfigResponse::UP createOKResponse(const ConfigKey & key, const ConfigValue & value)
+    {
+        return ConfigResponse::UP(new MyConfigResponse(key, value, true, true, 10, "a", "", 0, false));
+    }
+
+    static ConfigResponse::UP createServerErrorResponse(const ConfigKey & key, const ConfigValue & value)
+    {
+        return ConfigResponse::UP(new MyConfigResponse(key, value, false, true, 10, "a", "whinewhine", 2, true));
+    }
+
+    static ConfigResponse::UP createConfigErrorResponse(const ConfigKey & key, const ConfigValue & value)
+    {
+        return ConfigResponse::UP(new MyConfigResponse(key, value, false, false, 10, "a", "", 0, false));
+    }
+};
+
+class MyHolder : public IConfigHolder
+{
+public:
+    MyHolder()
+        : _update()
+    {
+    }
+
+    std::unique_ptr<ConfigUpdate> provide()
+    {
+        return std::move(_update);
+    }
+
+    bool wait(uint64_t timeout)
+    {
+        (void) timeout;
+        return true;
+    }
+
+    void handle(std::unique_ptr<ConfigUpdate> update)
+    {
+        _update = std::move(update);
+    }
+
+    bool poll() { return true; }
+    void interrupt() { }
+private:
+    std::unique_ptr<ConfigUpdate> _update;
+};
+
+
+ConfigValue createValue(const std::string & myField, const std::string & md5)
+{
+    std::vector< vespalib::string > lines;
+    lines.push_back("myField \"" + myField + "\"");
+    return ConfigValue(lines, md5);
+}
+
+static TimingValues testTimingValues(
+        2000,  // successTimeout
+        500,  // errorTimeout
+        500,   // initialTimeout
+        4000,  // subscribeTimeout
+        0,     // fixedDelay
+        250,   // successDelay
+        250,   // unconfiguredDelay
+        500,   // configuredErrorDelay
+        5,
+        1000,
+        2000);    // maxDelayMultiplier
+
+TEST("require that agent returns correct values") {
+    FRTConfigAgent handler(IConfigHolder::SP(new MyHolder()), testTimingValues);
+    ASSERT_EQUAL(500u, handler.getTimeout());
+    ASSERT_EQUAL(0u, handler.getWaitTime());
+    ConfigState cs;
+    ASSERT_EQUAL(cs.md5, handler.getConfigState().md5);
+    ASSERT_EQUAL(cs.generation, handler.getConfigState().generation);
+}
+
+TEST("require that successful request is delivered to holder") {
+    const ConfigKey testKey(ConfigKey::create<MyConfig>("mykey"));
+    const ConfigValue testValue(createValue("l33t", "a"));
+    IConfigHolder::SP latch(new MyHolder());
+
+    FRTConfigAgent handler(latch, testTimingValues);
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createOKResponse(testKey, testValue));
+    ASSERT_TRUE(latch->poll());
+    ConfigUpdate::UP update(latch->provide());
+    ASSERT_TRUE(update.get() != NULL);
+    ASSERT_TRUE(update->hasChanged());
+    MyConfig cfg(update->getValue());
+    ASSERT_EQUAL("l33t", cfg.myField);
+}
+
+TEST("require that successful request sets correct wait time") {
+    const ConfigKey testKey(ConfigKey::create<MyConfig>("mykey"));
+    const ConfigValue testValue(createValue("l33t", "a"));
+    IConfigHolder::SP latch(new MyHolder());
+    FRTConfigAgent handler(latch, testTimingValues);
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createOKResponse(testKey, testValue));
+    ASSERT_EQUAL(250u, handler.getWaitTime());
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createOKResponse(testKey, testValue));
+    ASSERT_EQUAL(250u, handler.getWaitTime());
+}
+
+TEST("require that bad config response returns false") {
+    const ConfigKey testKey(ConfigKey::create<MyConfig>("mykey"));
+    const ConfigValue testValue(createValue("myval", "a"));
+    IConfigHolder::SP latch(new MyHolder());
+    FRTConfigAgent handler(latch, testTimingValues);
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createConfigErrorResponse(testKey, testValue));
+    ASSERT_EQUAL(250u, handler.getWaitTime());
+    ASSERT_EQUAL(500u, handler.getTimeout());
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createConfigErrorResponse(testKey, testValue));
+    ASSERT_EQUAL(500u, handler.getWaitTime());
+    ASSERT_EQUAL(500u, handler.getTimeout());
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createConfigErrorResponse(testKey, testValue));
+    ASSERT_EQUAL(750u, handler.getWaitTime());
+    ASSERT_EQUAL(500u, handler.getTimeout());
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createConfigErrorResponse(testKey, testValue));
+    ASSERT_EQUAL(1000u, handler.getWaitTime());
+    ASSERT_EQUAL(500u, handler.getTimeout());
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createConfigErrorResponse(testKey, testValue));
+    ASSERT_EQUAL(1250u, handler.getWaitTime());
+    ASSERT_EQUAL(500u, handler.getTimeout());
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createConfigErrorResponse(testKey, testValue));
+    ASSERT_EQUAL(1250u, handler.getWaitTime());
+    ASSERT_EQUAL(500u, handler.getTimeout());
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createOKResponse(testKey, testValue));
+    ASSERT_EQUAL(250u, handler.getWaitTime());
+    ASSERT_EQUAL(2000u, handler.getTimeout());
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createConfigErrorResponse(testKey, testValue));
+    ASSERT_EQUAL(500u, handler.getWaitTime());
+    ASSERT_EQUAL(500u, handler.getTimeout());
+}
+
+TEST("require that bad response returns false") {
+    const ConfigKey testKey(ConfigKey::create<MyConfig>("mykey"));
+    std::vector<vespalib::string> lines;
+    const ConfigValue testValue(lines, "a");
+
+    IConfigHolder::SP latch(new MyHolder());
+    FRTConfigAgent handler(latch, testTimingValues);
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createServerErrorResponse(testKey, testValue));
+    ASSERT_EQUAL(250u, handler.getWaitTime());
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createServerErrorResponse(testKey, testValue));
+    ASSERT_EQUAL(500u, handler.getWaitTime());
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createServerErrorResponse(testKey, testValue));
+    ASSERT_EQUAL(750u, handler.getWaitTime());
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createServerErrorResponse(testKey, testValue));
+    ASSERT_EQUAL(1000u, handler.getWaitTime());
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createServerErrorResponse(testKey, testValue));
+    ASSERT_EQUAL(1250u, handler.getWaitTime());
+
+    handler.handleResponse(MyConfigRequest(testKey), MyConfigResponse::createServerErrorResponse(testKey, testValue));
+    ASSERT_EQUAL(1250u, handler.getWaitTime());
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/configeventqueue/.gitignore b/config/src/tests/configeventqueue/.gitignore
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/tests/configeventqueue/.gitignore
diff --git a/config/src/tests/configfetcher/.gitignore b/config/src/tests/configfetcher/.gitignore
new file mode 100644
index 00000000000..459ea6bbcfa
--- /dev/null
+++ b/config/src/tests/configfetcher/.gitignore
@@ -0,0 +1,3 @@
+/config-my.cpp
+/config-my.h
+config_configfetcher_test_app
diff --git a/config/src/tests/configfetcher/CMakeLists.txt b/config/src/tests/configfetcher/CMakeLists.txt
new file mode 100644
index 00000000000..58598815f7d
--- /dev/null
+++ b/config/src/tests/configfetcher/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_configfetcher_test_app
+    SOURCES
+    configfetcher.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_configfetcher_test_app COMMAND config_configfetcher_test_app)
+vespa_generate_config(config_configfetcher_test_app ../../test/resources/configdefinitions/my.def)
diff --git a/config/src/tests/configfetcher/configfetcher.cpp b/config/src/tests/configfetcher/configfetcher.cpp
new file mode 100644
index 00000000000..6d319fdff67
--- /dev/null
+++ b/config/src/tests/configfetcher/configfetcher.cpp
@@ -0,0 +1,158 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/helper/configfetcher.h>
+#include <fstream>
+#include "config-my.h"
+#include <atomic>
+
+using namespace config;
+
+
+class MyCallback : public IFetcherCallback<MyConfig>
+{
+public:
+    MyCallback(const std::string & badConfig="") : _config(), _configured(false), _badConfig(badConfig) { }
+    void configure(std::unique_ptr<MyConfig> config)
+    {
+        _config = std::move(config);
+        _configured = true;
+        if (_config->myField.compare(_badConfig) == 0) {
+            throw vespalib::Exception("Buhu");
+        }
+    }
+    std::unique_ptr<MyConfig> _config;
+    std::atomic<bool> _configured;
+    std::string _badConfig;
+};
+
+TEST("requireThatConfigIsAvailableOnConstruction") {
+    RawSpec spec("myField \"foo\"\n");
+    MyCallback cb;
+
+    {
+        ConfigFetcher fetcher(spec);
+        fetcher.subscribe<MyConfig>("myid", &cb);
+        fetcher.start();
+        ASSERT_TRUE(cb._config.get() != NULL);
+        ASSERT_EQUAL("my", cb._config->defName());
+        ASSERT_EQUAL("foo", cb._config->myField);
+    }
+}
+
+#if 0
+TEST("requireThatConfigUpdatesArePerformed") {
+    writeFile("test1.cfg", "foo");
+    FileSpec spec("test1.cfg");
+    MyCallback cb;
+    cb._configured = false;
+    vespalib::ThreadStackExecutor executor(1, 128 * 1024);
+
+    {
+        ConfigFetcher fetcher(500);
+        fetcher.subscribe<MyConfig>("test1", &cb, spec);
+        fetcher.start();
+        ASSERT_TRUE(cb._configured);
+        ASSERT_TRUE(cb._config.get() != NULL);
+        ASSERT_EQUAL("my", cb._config->defName());
+        ASSERT_EQUAL("foo", cb._config->myField);
+
+        sleep(2);
+        writeFile("test1.cfg", "bar");
+
+        cb._configured = false;
+        FastOS_Time timer;
+        timer.SetNow();
+        while (!cb._configured && timer.MilliSecsToNow() < 20000.0) {
+            if (cb._configured)
+                break;
+            FastOS_Thread::Sleep(1000);
+        }
+        ASSERT_TRUE(cb._configured);
+        ASSERT_TRUE(cb._config.get() != NULL);
+        ASSERT_EQUAL("my", cb._config->defName());
+        ASSERT_EQUAL("bar", cb._config->myField);
+    }
+}
+#endif
+
+TEST("requireThatFetcherCanHandleMultipleConfigs") {
+    MyConfigBuilder b1, b2;
+    b1.myField = "foo";
+    b2.myField = "bar";
+    ConfigSet set;
+    set.addBuilder("test1", &b1);
+    set.addBuilder("test2", &b2);
+    MyCallback cb1;
+    MyCallback cb2;
+
+    {
+        ConfigFetcher fetcher(set);
+        fetcher.subscribe<MyConfig>("test1", &cb1);
+        fetcher.subscribe<MyConfig>("test2", &cb2);
+        fetcher.start();
+
+        ASSERT_TRUE(cb1._configured);
+        ASSERT_TRUE(cb2._configured);
+        ASSERT_TRUE(cb1._config.get() != NULL);
+        ASSERT_TRUE(cb2._config.get() != NULL);
+        ASSERT_EQUAL("my", cb1._config->defName());
+        ASSERT_EQUAL("foo", cb1._config->myField);
+        ASSERT_EQUAL("my", cb2._config->defName());
+        ASSERT_EQUAL("bar", cb2._config->myField);
+    }
+}
+
+TEST("verify that exceptions in callback is thrown on initial subscribe") {
+    MyConfigBuilder b1;
+    b1.myField = "foo";
+    ConfigSet set;
+    set.addBuilder("test1", &b1);
+    MyCallback cb("foo");
+    {
+        ConfigFetcher fetcher(set);
+        fetcher.subscribe<MyConfig>("test1", &cb);
+        ASSERT_EXCEPTION(fetcher.start(), vespalib::Exception, "Buhu");
+    }
+}
+
+namespace {
+
+struct ConfigFixture {
+    MyConfigBuilder builder;
+    ConfigSet set;
+    ConfigContext::SP context;
+    ConfigFixture() : builder(), set(), context() {
+        set.addBuilder("cfgid", &builder);
+        context.reset(new ConfigContext(set));
+    }
+};
+
+} // namespace <unnamed>
+
+TEST_F("verify that config generation can be obtained from config fetcher", ConfigFixture) {
+    f1.builder.myField = "foo";
+    MyCallback cb;
+    {
+        ConfigFetcher fetcher(f1.context);
+        fetcher.subscribe<MyConfig>("cfgid", &cb);
+        fetcher.start();
+        EXPECT_EQUAL("foo", cb._config.get()->myField);
+        EXPECT_EQUAL(1, fetcher.getGeneration());
+        f1.builder.myField = "bar";
+        cb._configured = false;
+        f1.context->reload();
+        FastOS_Time timer;
+        timer.SetNow();
+        while (timer.MilliSecsToNow() < 120000) {
+            if (cb._configured) {
+                break;
+            }
+            FastOS_Thread::Sleep(10);
+        }
+        EXPECT_EQUAL(2, fetcher.getGeneration());
+        EXPECT_EQUAL("bar", cb._config.get()->myField);
+    }
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/configformat/.gitignore b/config/src/tests/configformat/.gitignore
new file mode 100644
index 00000000000..fe015963e1c
--- /dev/null
+++ b/config/src/tests/configformat/.gitignore
@@ -0,0 +1,3 @@
+/config-my.cpp
+/config-my.h
+config_configformat_test_app
diff --git a/config/src/tests/configformat/CMakeLists.txt b/config/src/tests/configformat/CMakeLists.txt
new file mode 100644
index 00000000000..f17215bc66c
--- /dev/null
+++ b/config/src/tests/configformat/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_configformat_test_app
+    SOURCES
+    configformat.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_configformat_test_app COMMAND config_configformat_test_app)
+vespa_generate_config(config_configformat_test_app ../../test/resources/configdefinitions/my.def)
diff --git a/config/src/tests/configformat/configformat.cpp b/config/src/tests/configformat/configformat.cpp
new file mode 100644
index 00000000000..5ed10b81023
--- /dev/null
+++ b/config/src/tests/configformat/configformat.cpp
@@ -0,0 +1,23 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/config.h>
+#include <vespa/config/print/fileconfigformatter.h>
+#include <vespa/vespalib/data/slime/slime.h>
+
+using namespace config;
+using namespace vespalib::slime::convenience;
+
+TEST("requireThatConfigIsFormatted") {
+    ConfigDataBuffer buffer;
+    vespalib::Slime & slime(buffer.slimeObject());
+    Cursor &c = slime.setObject().setObject("configPayload").setObject("myField");
+    c.setString("type", "string");
+    c.setString("value", "foo");
+
+    FileConfigFormatter formatter;
+    formatter.encode(buffer);
+    EXPECT_EQUAL(std::string("myField \"foo\"\n"), buffer.getEncodedString());
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/configgen/.gitignore b/config/src/tests/configgen/.gitignore
new file mode 100644
index 00000000000..e021b74ec3f
--- /dev/null
+++ b/config/src/tests/configgen/.gitignore
@@ -0,0 +1,6 @@
+/config-motd.cpp
+/config-motd.h
+config_configgen_test_app
+config_map_inserter_test_app
+config_value_converter_test_app
+config_vector_inserter_test_app
diff --git a/config/src/tests/configgen/CMakeLists.txt b/config/src/tests/configgen/CMakeLists.txt
new file mode 100644
index 00000000000..8a71b737919
--- /dev/null
+++ b/config/src/tests/configgen/CMakeLists.txt
@@ -0,0 +1,31 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_configgen_test_app
+    SOURCES
+    configgen.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_configgen_test_app COMMAND config_configgen_test_app)
+vespa_generate_config(config_configgen_test_app ../../test/resources/configdefinitions/motd.def)
+vespa_add_executable(config_vector_inserter_test_app
+    SOURCES
+    vector_inserter.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_vector_inserter_test_app COMMAND config_vector_inserter_test_app)
+vespa_add_executable(config_map_inserter_test_app
+    SOURCES
+    map_inserter.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_map_inserter_test_app COMMAND config_map_inserter_test_app)
+vespa_add_executable(config_value_converter_test_app
+    SOURCES
+    value_converter.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_value_converter_test_app COMMAND config_value_converter_test_app)
+vespa_generate_config(config_value_converter_test_app ../../test/resources/configdefinitions/motd.def)
diff --git a/config/src/tests/configgen/configgen.cpp b/config/src/tests/configgen/configgen.cpp
new file mode 100644
index 00000000000..786268e7287
--- /dev/null
+++ b/config/src/tests/configgen/configgen.cpp
@@ -0,0 +1,15 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP("configgen");
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/config.h>
+#include "config-motd.h"
+
+using namespace config;
+
+TEST("require that config type can be compiled") {
+    std::unique_ptr<MotdConfig> cfg = ConfigGetter<MotdConfig>::getConfig("motd", FileSpec("motd.cfg"));
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/configgen/map_inserter.cpp b/config/src/tests/configgen/map_inserter.cpp
new file mode 100644
index 00000000000..5f37a4fdb4f
--- /dev/null
+++ b/config/src/tests/configgen/map_inserter.cpp
@@ -0,0 +1,118 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP("map_inserter");
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/configgen/map_inserter.h>
+
+using namespace config;
+using namespace config::internal;
+using namespace vespalib;
+using namespace vespalib::slime;
+
+struct MyType{
+    MyType() : foo(0), bar(0) {}
+    MyType(const ConfigPayload & payload)
+    {
+        foo = payload.get()["foo"].asLong();
+        bar = payload.get()["bar"].asLong();
+    }
+    int foo;
+    int bar;
+};
+
+TEST("require that map of ints can be inserted") {
+    std::map<vespalib::string, int32_t> map;
+    Slime slime;
+    Cursor & root = slime.setObject();
+    root.setLong("foo", 3);
+    root.setLong("bar", 2);
+    root.setLong("baz", 6);
+    MapInserter<int32_t> inserter(map);
+    root.traverse(inserter);
+    ASSERT_EQUAL(3u, map.size());
+    ASSERT_EQUAL(3, map["foo"]);
+    ASSERT_EQUAL(2, map["bar"]);
+    ASSERT_EQUAL(6, map["baz"]);
+}
+
+TEST("require that map of struct can be inserted") {
+    std::map<vespalib::string, MyType> map;
+    Slime slime;
+    Cursor & root = slime.setObject();
+    Cursor & one = root.setObject("foo");
+    one.setLong("foo", 3);
+    one.setLong("bar", 4);
+    Cursor & two = root.setObject("bar");
+    two.setLong("foo", 1);
+    two.setLong("bar", 6);
+    MapInserter<MyType> inserter(map);
+    root.traverse(inserter);
+    ASSERT_EQUAL(2u, map.size());
+    ASSERT_EQUAL(3, map["foo"].foo);
+    ASSERT_EQUAL(4, map["foo"].bar);
+    ASSERT_EQUAL(1, map["bar"].foo);
+    ASSERT_EQUAL(6, map["bar"].bar);
+}
+
+TEST("require that map of long can be inserted") {
+    std::map<vespalib::string, int64_t> map;
+    Slime slime;
+    Cursor & root = slime.setObject();
+    root.setLong("foo", 3);
+    root.setLong("bar", 2);
+    root.setLong("baz", 6);
+    MapInserter<int64_t> inserter(map);
+    root.traverse(inserter);
+    ASSERT_EQUAL(3u, map.size());
+    ASSERT_EQUAL(3, map["foo"]);
+    ASSERT_EQUAL(2, map["bar"]);
+    ASSERT_EQUAL(6, map["baz"]);
+}
+
+TEST("require that map of double can be inserted") {
+    std::map<vespalib::string, double> map;
+    Slime slime;
+    Cursor & root = slime.setObject();
+    root.setDouble("foo", 3.1);
+    root.setDouble("bar", 2.4);
+    root.setDouble("baz", 6.6);
+    MapInserter<double> inserter(map);
+    root.traverse(inserter);
+    ASSERT_EQUAL(3u, map.size());
+    ASSERT_EQUAL(3.1, map["foo"]);
+    ASSERT_EQUAL(2.4, map["bar"]);
+    ASSERT_EQUAL(6.6, map["baz"]);
+}
+
+TEST("require that map of bool can be inserted") {
+    std::map<vespalib::string, bool> map;
+    Slime slime;
+    Cursor & root = slime.setObject();
+    root.setBool("foo", true);
+    root.setBool("bar", false);
+    root.setBool("baz", true);
+    MapInserter<bool> inserter(map);
+    root.traverse(inserter);
+    ASSERT_EQUAL(3u, map.size());
+    ASSERT_TRUE(map["foo"]);
+    ASSERT_FALSE(map["bar"]);
+    ASSERT_TRUE(map["baz"]);
+}
+
+TEST("require that map of string can be inserted") {
+    std::map<vespalib::string, vespalib::string> map;
+    Slime slime;
+    Cursor & root = slime.setObject();
+    root.setString("foo", "baz");
+    root.setString("bar", "bar");
+    root.setString("baz", "foo");
+    MapInserter<vespalib::string> inserter(map);
+    root.traverse(inserter);
+    ASSERT_EQUAL(3u, map.size());
+    ASSERT_EQUAL("foo", map["baz"]);
+    ASSERT_EQUAL("bar", map["bar"]);
+    ASSERT_EQUAL("baz", map["foo"]);
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/configgen/motd.cfg b/config/src/tests/configgen/motd.cfg
new file mode 100644
index 00000000000..3b511ce35b2
--- /dev/null
+++ b/config/src/tests/configgen/motd.cfg
@@ -0,0 +1,22 @@
+intVal 1
+longVal 1
+doubleVal 2.3
+stringVal "foo"
+stringnulldef "foo"
+enumVal FOOBAR
+refVal "refVal"
+fileVal "fileVal"
+boolVal true
+boolarr[2]
+boolarr[0] true
+boolarr[1] false
+myArray[2]
+myArray[0].stringVal[1]
+myArray[0].stringVal[0] "bla"
+myArray[0].refVal "habba"
+myArray[1].stringVal[1]
+myArray[1].stringVal[0] "blabla"
+myArray[1].refVal "nabba"
+myArray[1].anotherArray[1]
+myArray[1].anotherArray[0].foo 1337
+
diff --git a/config/src/tests/configgen/value_converter.cpp b/config/src/tests/configgen/value_converter.cpp
new file mode 100644
index 00000000000..467075354f2
--- /dev/null
+++ b/config/src/tests/configgen/value_converter.cpp
@@ -0,0 +1,105 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP("value_converter");
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/configgen/value_converter.h>
+#include <vespa/config/common/exceptions.h>
+
+using namespace config;
+using namespace config::internal;
+using namespace vespalib;
+using namespace vespalib::slime;
+
+struct MyType{
+    MyType(const ConfigPayload & payload)
+    {
+        foo = payload.get()["foo"].asLong();
+        bar = payload.get()["bar"].asLong();
+    }
+    int foo;
+    int bar;
+};
+
+TEST("that int32_ts are converted") {
+    Slime slime;
+    Cursor & root = slime.setArray();
+    root.addLong(3);
+    root.addLong(-2);
+    root.addLong(INT_MAX);
+    root.addLong(INT_MIN);
+    root.addDouble(3.14);
+    ValueConverter<int32_t> conv;
+    EXPECT_EQUAL(3, conv(root[0]));
+    EXPECT_EQUAL(-2, conv(root[1]));
+    EXPECT_EQUAL(INT_MAX, conv(root[2]));
+    EXPECT_EQUAL(INT_MIN, conv(root[3]));
+    EXPECT_EQUAL(3, conv(root[4]));
+}
+
+TEST("that int64_ts are converted") {
+    Slime slime;
+    Cursor & root = slime.setArray();
+    root.addLong(3);
+    root.addLong(-2);
+    root.addLong(LONG_MAX);
+    root.addLong(LONG_MIN);
+    root.addLong(std::numeric_limits<int64_t>::max());
+    root.addLong(std::numeric_limits<int64_t>::min());
+    root.addDouble(3.14);
+    std::string ref = "{\"val\":9223372036854775807}";
+    Slime slime2;
+    JsonFormat::decode(ref, slime2);
+    EXPECT_EQUAL(std::numeric_limits<int64_t>::max(), slime2.get()["val"].asLong());
+    ValueConverter<int64_t> conv;
+    EXPECT_EQUAL(3, conv(root[0]));
+    EXPECT_EQUAL(-2, conv(root[1]));
+    EXPECT_EQUAL(LONG_MAX, conv(root[2]));
+    EXPECT_EQUAL(LONG_MIN, conv(root[3]));
+    EXPECT_EQUAL(std::numeric_limits<int64_t>::max(), conv(root[4]));
+    EXPECT_EQUAL(std::numeric_limits<int64_t>::min(), conv(root[5]));
+    EXPECT_EQUAL(3, conv(root[6]));
+}
+
+TEST("that values can be parsed as strings") {
+    Slime slime;
+    Cursor & root = slime.setObject();
+    root.setString("intval", "1234");
+    root.setString("longval", "42949672969");
+    root.setString("boolval", "true");
+    root.setString("doubleval", "3.14");
+    ValueConverter<int32_t> intConv;
+    ValueConverter<int64_t> longConv;
+    ValueConverter<bool> boolConv;
+    ValueConverter<double> doubleConv;
+    EXPECT_EQUAL(1234, intConv(root["intval"]));
+    EXPECT_EQUAL(42949672969, longConv(root["longval"]));
+    EXPECT_EQUAL(true, boolConv(root["boolval"]));
+    EXPECT_APPROX(3.14, doubleConv(root["doubleval"]), 0.0001);
+}
+
+TEST("that incompatible types throws exceptions") {
+    Slime slime;
+    Cursor & root = slime.setObject();
+    root.setBool("intval", true);
+    root.setBool("longval", true);
+    root.setBool("doubleval", true);
+    root.setLong("boolval", 3);
+    ValueConverter<int32_t> intConv;
+    ValueConverter<int64_t> longConv;
+    ValueConverter<bool> boolConv;
+    ValueConverter<double> doubleConv;
+    EXPECT_EXCEPTION(intConv(root["intval"]), InvalidConfigException, "");
+    EXPECT_EXCEPTION(longConv(root["longval"]), InvalidConfigException, "");
+    EXPECT_EXCEPTION(doubleConv(root["doubleval"]), InvalidConfigException, "");
+    EXPECT_EXCEPTION(boolConv(root["boolval"]), InvalidConfigException, "");
+}
+
+TEST("that non-valid fields throws exception") {
+    Slime slime;
+    Cursor & root = slime.setObject();
+    ValueConverter<int64_t> conv;
+    EXPECT_EXCEPTION(conv("longval", root["longval"]), InvalidConfigException, "Value for 'longval' required but not found");
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/configgen/vector_inserter.cpp b/config/src/tests/configgen/vector_inserter.cpp
new file mode 100644
index 00000000000..e9f16f804b3
--- /dev/null
+++ b/config/src/tests/configgen/vector_inserter.cpp
@@ -0,0 +1,118 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP("vector_inserter");
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/configgen/vector_inserter.h>
+
+using namespace config;
+using namespace config::internal;
+using namespace vespalib;
+using namespace vespalib::slime;
+
+struct MyType{
+    MyType() : foo(0), bar(0) {}
+    MyType(const ConfigPayload & payload)
+    {
+        foo = payload.get()["foo"].asLong();
+        bar = payload.get()["bar"].asLong();
+    }
+    int foo;
+    int bar;
+};
+
+TEST("require that vector of ints can be inserted") {
+    std::vector<int32_t> vector;
+    Slime slime;
+    Cursor & root = slime.setArray();
+    root.addLong(3);
+    root.addLong(2);
+    root.addLong(6);
+    VectorInserter<int32_t> inserter(vector);
+    root.traverse(inserter);
+    ASSERT_EQUAL(3u, vector.size());
+    ASSERT_EQUAL(3, vector[0]);
+    ASSERT_EQUAL(2, vector[1]);
+    ASSERT_EQUAL(6, vector[2]);
+}
+
+TEST("require that vector of struct can be inserted") {
+    std::vector<MyType> typeVector;
+    Slime slime;
+    Cursor & root = slime.setArray();
+    Cursor & one = root.addObject();
+    one.setLong("foo", 3);
+    one.setLong("bar", 4);
+    Cursor & two = root.addObject();
+    two.setLong("foo", 1);
+    two.setLong("bar", 6);
+    VectorInserter<MyType> inserter(typeVector);
+    root.traverse(inserter);
+    ASSERT_EQUAL(2u, typeVector.size());
+    ASSERT_EQUAL(3, typeVector[0].foo);
+    ASSERT_EQUAL(4, typeVector[0].bar);
+    ASSERT_EQUAL(1, typeVector[1].foo);
+    ASSERT_EQUAL(6, typeVector[1].bar);
+}
+
+TEST("require that vector of long can be inserted") {
+    std::vector<int64_t> vector;
+    Slime slime;
+    Cursor & root = slime.setArray();
+    root.addLong(3);
+    root.addLong(2);
+    root.addLong(6);
+    VectorInserter<int64_t> inserter(vector);
+    root.traverse(inserter);
+    ASSERT_EQUAL(3u, vector.size());
+    ASSERT_EQUAL(3, vector[0]);
+    ASSERT_EQUAL(2, vector[1]);
+    ASSERT_EQUAL(6, vector[2]);
+}
+
+TEST("require that vector of double can be inserted") {
+    std::vector<double> vector;
+    Slime slime;
+    Cursor & root = slime.setArray();
+    root.addDouble(3.1);
+    root.addDouble(2.4);
+    root.addDouble(6.6);
+    VectorInserter<double> inserter(vector);
+    root.traverse(inserter);
+    ASSERT_EQUAL(3u, vector.size());
+    ASSERT_EQUAL(3.1, vector[0]);
+    ASSERT_EQUAL(2.4, vector[1]);
+    ASSERT_EQUAL(6.6, vector[2]);
+}
+
+TEST("require that vector of bool can be inserted") {
+    std::vector<bool> vector;
+    Slime slime;
+    Cursor & root = slime.setArray();
+    root.addBool(true);
+    root.addBool(false);
+    root.addBool(true);
+    VectorInserter<bool> inserter(vector);
+    root.traverse(inserter);
+    ASSERT_EQUAL(3u, vector.size());
+    ASSERT_TRUE(vector[0]);
+    ASSERT_FALSE(vector[1]);
+    ASSERT_TRUE(vector[2]);
+}
+
+TEST("require that vector of string can be inserted") {
+    std::vector<vespalib::string> vector;
+    Slime slime;
+    Cursor & root = slime.setArray();
+    root.addString("foo");
+    root.addString("bar");
+    root.addString("baz");
+    VectorInserter<vespalib::string> inserter(vector);
+    root.traverse(inserter);
+    ASSERT_EQUAL(3u, vector.size());
+    ASSERT_EQUAL("foo", vector[0]);
+    ASSERT_EQUAL("bar", vector[1]);
+    ASSERT_EQUAL("baz", vector[2]);
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/configholder/.gitignore b/config/src/tests/configholder/.gitignore
new file mode 100644
index 00000000000..1c0e7857e7a
--- /dev/null
+++ b/config/src/tests/configholder/.gitignore
@@ -0,0 +1 @@
+config_configholder_test_app
diff --git a/config/src/tests/configholder/CMakeLists.txt b/config/src/tests/configholder/CMakeLists.txt
new file mode 100644
index 00000000000..050160d2ad3
--- /dev/null
+++ b/config/src/tests/configholder/CMakeLists.txt
@@ -0,0 +1,8 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_configholder_test_app
+    SOURCES
+    configholder.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_configholder_test_app COMMAND config_configholder_test_app)
diff --git a/config/src/tests/configholder/configholder.cpp b/config/src/tests/configholder/configholder.cpp
new file mode 100644
index 00000000000..b11d2009ebf
--- /dev/null
+++ b/config/src/tests/configholder/configholder.cpp
@@ -0,0 +1,71 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/common/configholder.h>
+
+using namespace config;
+
+TEST("Require that element order is correct")
+{
+    ConfigValue value(std::vector<vespalib::string>(), "foo");
+    ConfigValue value2(std::vector<vespalib::string>(), "bar");
+
+    ConfigHolder holder;
+    holder.handle(ConfigUpdate::UP(new ConfigUpdate(value, true, 0)));
+    std::unique_ptr<ConfigUpdate> update = holder.provide();
+    ASSERT_TRUE(value == update->getValue());
+
+    holder.handle(ConfigUpdate::UP(new ConfigUpdate(value, false, 1)));
+    holder.handle(ConfigUpdate::UP(new ConfigUpdate(value2, false, 2)));
+    update = holder.provide();
+    ASSERT_TRUE(value2 == update->getValue());
+}
+
+TEST("Require that waiting is done")
+{
+    ConfigValue value;
+
+    ConfigHolder holder;
+    FastOS_Time timer;
+    timer.SetNow();
+    holder.wait(1000);
+    ASSERT_TRUE(timer.MilliSecsToNow() >= 1000);
+    ASSERT_TRUE(timer.MilliSecsToNow() < 60000);
+
+    timer.SetNow();
+    holder.handle(ConfigUpdate::UP(new ConfigUpdate(value, true, 0)));
+    holder.wait(100);
+    ASSERT_TRUE(timer.MilliSecsToNow() >= 100);
+}
+
+TEST("Require that polling for elements work")
+{
+    ConfigValue value;
+
+    ConfigHolder holder;
+    ASSERT_FALSE(holder.poll());
+    holder.handle(ConfigUpdate::UP(new ConfigUpdate(value, true, 0)));
+    ASSERT_TRUE(holder.poll());
+    holder.provide();
+    ASSERT_TRUE(holder.poll());
+}
+
+TEST_MT_F("Require that wait is interrupted", 2, ConfigHolder)
+{
+    if (thread_id == 0) {
+        FastOS_Time timer;
+        timer.SetNow();
+        TEST_BARRIER();
+        f.wait(1000);
+        EXPECT_TRUE(timer.MilliSecsToNow() < 60000.0);
+        EXPECT_TRUE(timer.MilliSecsToNow() > 400.0);
+        TEST_BARRIER();
+    } else {
+        TEST_BARRIER();
+        FastOS_Thread::Sleep(500);
+        f.interrupt();
+        TEST_BARRIER();
+    }
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/configmanager/.gitignore b/config/src/tests/configmanager/.gitignore
new file mode 100644
index 00000000000..0ac5d3be182
--- /dev/null
+++ b/config/src/tests/configmanager/.gitignore
@@ -0,0 +1,3 @@
+/config-my.cpp
+/config-my.h
+config_configmanager_test_app
diff --git a/config/src/tests/configmanager/CMakeLists.txt b/config/src/tests/configmanager/CMakeLists.txt
new file mode 100644
index 00000000000..87c11296dea
--- /dev/null
+++ b/config/src/tests/configmanager/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_configmanager_test_app
+    SOURCES
+    configmanager.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_configmanager_test_app COMMAND config_configmanager_test_app)
+vespa_generate_config(config_configmanager_test_app ../../test/resources/configdefinitions/my.def)
diff --git a/config/src/tests/configmanager/configmanager.cpp b/config/src/tests/configmanager/configmanager.cpp
new file mode 100644
index 00000000000..7d116477f1d
--- /dev/null
+++ b/config/src/tests/configmanager/configmanager.cpp
@@ -0,0 +1,186 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP("configmanager");
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/vespalib/util/noncopyable.hpp>
+#include <vespa/config/common/configmanager.h>
+#include <vespa/config/common/exceptions.h>
+#include <vespa/config/subscription/sourcespec.h>
+#include <vespa/config/raw/rawsource.h>
+#include "config-my.h"
+
+using namespace config;
+
+namespace {
+
+    ConfigValue createValue(const std::string & myField, const std::string & md5)
+    {
+        std::vector< vespalib::string > lines;
+        lines.push_back("myField \"" + myField + "\"");
+        return ConfigValue(lines, md5);
+    }
+
+    struct TestContext
+    {
+        int numGetConfig;
+        int numUpdate;
+        int numClose;
+        int64_t generation;
+        bool respond;
+        TestContext()
+            : numGetConfig(0), numUpdate(0), numClose(0), generation(-1), respond(true)
+        { }
+    };
+
+    class MySource : public Source
+    {
+    public:
+        MySource(TestContext * data, const IConfigHolder::SP & holder) : _holder(holder), _data(data) { }
+        void getConfig()
+        {
+            _data->numGetConfig++;
+            if (_data->respond) {
+                LOG(info, "put into holder");
+                _holder->handle(ConfigUpdate::UP(new ConfigUpdate(ConfigValue(), true, _data->generation)));
+            }
+        }
+        void reload(int64_t generation)
+        {
+            _data->numUpdate++;
+            _data->generation = generation;
+        }
+        void close()
+        {
+            _data->numClose++;
+        }
+        IConfigHolder::SP _holder;
+        TestContext * _data;
+    };
+
+    class MySourceFactory : public SourceFactory
+    {
+    public:
+        MySourceFactory(TestContext * d) : data(d) { }
+        Source::UP createSource(const IConfigHolder::SP & holder, const ConfigKey & key) const
+        {
+            (void) key;
+            return Source::UP(new MySource(data, holder));
+        }
+        TestContext * data;
+    };
+
+    class MySpec : public SourceSpec
+    {
+    public:
+        MySpec(TestContext * data)
+            : _key("foo"),
+              _data(data)
+        {
+        }
+        SourceSpecKey createKey() const { return SourceSpecKey(_key); }
+        SourceFactory::UP createSourceFactory(const TimingValues & timingValues) const {
+            (void) timingValues;
+            return SourceFactory::UP(new MySourceFactory(_data));
+        }
+        SourceSpec * clone() const { return new MySpec(*this); }
+    private:
+        const std::string _key;
+        TestContext * _data;
+    };
+
+    static TimingValues testTimingValues(
+            2000,  // successTimeout
+            500,  // errorTimeout
+            500,   // initialTimeout
+            4000,  // unsubscribeTimeout
+            0,     // fixedDelay
+            250,   // successDelay
+            250,   // unconfiguredDelay
+            500,   // configuredErrorDelay
+            5,
+            1000,
+            2000);    // maxDelayMultiplier
+
+    class ManagerTester {
+    public:
+        ConfigKey key;
+        ConfigManager _mgr;
+        ConfigSubscription::SP sub;
+
+        ManagerTester(const ConfigKey & k, const MySpec & s)
+            : key(k),
+              _mgr(s.createSourceFactory(testTimingValues), 1)
+        {
+        }
+
+        void subscribe()
+        {
+            sub = _mgr.subscribe(key, 5000);
+        }
+    };
+
+}
+
+TEST("requireThatSubscriptionTimesout") {
+    const ConfigKey key(ConfigKey::create<MyConfig>("myid"));
+    const ConfigValue testValue(createValue("l33t", "a"));
+
+    { // No valid response
+        TestContext data;
+        data.respond = false;
+
+        ManagerTester tester(ConfigKey::create<MyConfig>("myid"), MySpec(&data));
+        bool thrown = false;
+        try {
+            tester.subscribe();
+        } catch (const ConfigRuntimeException & e) {
+            thrown = true;
+        }
+        ASSERT_TRUE(thrown);
+        ASSERT_EQUAL(1, data.numGetConfig);
+    }
+}
+TEST("requireThatSourceIsAskedForRequest") {
+    TestContext data;
+    const ConfigKey key(ConfigKey::create<MyConfig>("myid"));
+    const ConfigValue testValue(createValue("l33t", "a"));
+    try {
+        ManagerTester tester(key, MySpec(&data));
+        tester.subscribe();
+        ASSERT_EQUAL(1, data.numGetConfig);
+    } catch (ConfigRuntimeException & e) {
+        ASSERT_TRUE(false);
+    }
+    ASSERT_EQUAL(1, data.numClose);
+}
+
+TEST("require that new sources are given the correct generation") {
+    TestContext data;
+    const ConfigKey key(ConfigKey::create<MyConfig>("myid"));
+    const ConfigValue testValue(createValue("l33t", "a"));
+    try {
+        ManagerTester tester(key, MySpec(&data));
+        tester._mgr.reload(30);
+        tester.subscribe();
+        ASSERT_EQUAL(30, data.generation);
+    } catch (ConfigRuntimeException & e) {
+        ASSERT_TRUE(false);
+    }
+}
+
+void waitForGet(TestContext & data, int preferred, double timeout)
+{
+    FastOS_Time timer;
+    timer.SetNow();
+    int numGet = -1;
+    while (timer.MilliSecsToNow() < timeout) {
+        numGet = data.numGetConfig;
+        if (numGet == preferred)
+            break;
+        FastOS_Thread::Sleep(50);
+    }
+    ASSERT_EQUAL(preferred, numGet);
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/configmanagerng/.gitignore b/config/src/tests/configmanagerng/.gitignore
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/tests/configmanagerng/.gitignore
diff --git a/config/src/tests/configparser/.gitignore b/config/src/tests/configparser/.gitignore
new file mode 100644
index 00000000000..6fca805f0df
--- /dev/null
+++ b/config/src/tests/configparser/.gitignore
@@ -0,0 +1,4 @@
+/config-foo.cpp
+/config-foo.h
+/foo.cfg
+config_configparser_test_app
diff --git a/config/src/tests/configparser/CMakeLists.txt b/config/src/tests/configparser/CMakeLists.txt
new file mode 100644
index 00000000000..d2bdaf09d40
--- /dev/null
+++ b/config/src/tests/configparser/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_configparser_test_app
+    SOURCES
+    configparser.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_configparser_test_app COMMAND config_configparser_test_app)
+vespa_generate_config(config_configparser_test_app ../../test/resources/configdefinitions/foo.def)
diff --git a/config/src/tests/configparser/configparser.cpp b/config/src/tests/configparser/configparser.cpp
new file mode 100644
index 00000000000..00e8929f64a
--- /dev/null
+++ b/config/src/tests/configparser/configparser.cpp
@@ -0,0 +1,145 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/config.h>
+#include <vespa/config/common/configparser.h>
+#include "config-foo.h"
+#include <fstream>
+#include <vespa/vespalib/stllike/asciistream.h>
+
+using namespace config;
+using vespalib::asciistream;
+
+namespace {
+
+    void writeFile(const vespalib::string & fileName, const vespalib::string & data)
+    {
+        std::ofstream of;
+        of.open(fileName.c_str());
+        of << data;
+        of.close();
+    }
+
+    ConfigValue readConfig(const vespalib::string & fileName)
+    {
+        asciistream is(asciistream::createFromFile(fileName));
+        return ConfigValue(is.getlines(), "");
+    }
+}
+
+TEST("require that default value exception provides error message")
+{
+    writeFile("foo.cfg", "blabla foo\n");
+    try {
+        FooConfig config(readConfig("foo.cfg"));
+        ASSERT_TRUE(false);
+    } catch (InvalidConfigException & ice) {
+        ASSERT_EQUAL("Error parsing config 'foo' in namespace 'config': Config parameter fooValue has no default value and is not specified in config", ice.getMessage());
+    }
+}
+
+TEST("require that unknown fields can exist in config payload")
+{
+    writeFile("foo.cfg", "blablabla foo\nfooValue \"hello\"\n");
+    try {
+        FooConfig config(readConfig("foo.cfg"));
+        ASSERT_EQUAL("hello", config.fooValue);
+    } catch (InvalidConfigException & ice) {
+        ASSERT_FALSE(true);
+    }
+}
+
+TEST("require that required fields will throw error with unknown fields")
+{
+    writeFile("foo.cfg", "blablabla foo\nfooValu \"hello\"\n");
+    try {
+        FooConfig config(readConfig("foo.cfg"));
+        ASSERT_TRUE(false);
+    } catch (InvalidConfigException & ice) {
+        ASSERT_TRUE(true);
+    }
+}
+
+TEST("require that array lengths does not have to be specified")
+{
+    writeFile("foo.cfg", "\nfooValue \"hello\"\nfooArray[0] 3\nfooArray[1] 9\nfooArray[2] 33\nfooStruct[0].innerStruct[0].bar 2\nfooStruct[0].innerStruct[1].bar 3\nfooStruct[1].innerStruct[0].bar 4");
+    try {
+        FooConfig config(readConfig("foo.cfg"));
+        ASSERT_EQUAL("hello", config.fooValue);
+        ASSERT_EQUAL(3u, config.fooArray.size());
+        ASSERT_EQUAL(3, config.fooArray[0]);
+        ASSERT_EQUAL(9, config.fooArray[1]);
+        ASSERT_EQUAL(33, config.fooArray[2]);
+        ASSERT_EQUAL(2u, config.fooStruct.size());
+        ASSERT_EQUAL(2u, config.fooStruct[0].innerStruct.size());
+        ASSERT_EQUAL(1u, config.fooStruct[1].innerStruct.size());
+        ASSERT_EQUAL(2, config.fooStruct[0].innerStruct[0].bar);
+        ASSERT_EQUAL(3, config.fooStruct[0].innerStruct[1].bar);
+        ASSERT_EQUAL(4, config.fooStruct[1].innerStruct[0].bar);
+    } catch (InvalidConfigException & ice) {
+        ASSERT_TRUE(false);
+    }
+}
+
+TEST("require that array lengths may be specified")
+{
+    writeFile("foo.cfg", "\nfooValue \"hello\"\nfooArray[3]\nfooArray[0] 3\nfooArray[1] 9\nfooArray[2] 33\nfooStruct[2]\nfooStruct[0].innerStruct[2]\nfooStruct[0].innerStruct[0].bar 2\nfooStruct[0].innerStruct[1].bar 3\nfooStruct[1].innerStruct[1]\nfooStruct[1].innerStruct[0].bar 4");
+    try {
+        FooConfig config(readConfig("foo.cfg"));
+        ASSERT_EQUAL("hello", config.fooValue);
+        ASSERT_EQUAL(3u, config.fooArray.size());
+        ASSERT_EQUAL(3, config.fooArray[0]);
+        ASSERT_EQUAL(9, config.fooArray[1]);
+        ASSERT_EQUAL(33, config.fooArray[2]);
+        ASSERT_EQUAL(2u, config.fooStruct[0].innerStruct.size());
+        ASSERT_EQUAL(1u, config.fooStruct[1].innerStruct.size());
+        ASSERT_EQUAL(2, config.fooStruct[0].innerStruct[0].bar);
+        ASSERT_EQUAL(3, config.fooStruct[0].innerStruct[1].bar);
+        ASSERT_EQUAL(4, config.fooStruct[1].innerStruct[0].bar);
+    } catch (InvalidConfigException & ice) {
+        ASSERT_TRUE(false);
+    }
+}
+
+TEST("require that escaped values are properly unescaped") {
+    std::vector<vespalib::string> payload;
+    payload.push_back("foo \"a\\nb\\rc\\\\d\\\"e\x42g\"");
+    vespalib::string value(ConfigParser::parse<vespalib::string>("foo", payload));
+    ASSERT_EQUAL("a\nb\rc\\d\"eBg", value);
+}
+
+TEST("verify that locale affects double parsing") {
+    std::vector<vespalib::string> payload;
+    setlocale(LC_NUMERIC, "nb_NO.UTF-8");
+    payload.push_back("foo 3.14");
+    ASSERT_EXCEPTION(ConfigParser::parse<double>("foo", payload), InvalidConfigException, "Value 3.14 is not a legal double");
+    setlocale(LC_NUMERIC, "C");
+}
+
+TEST("require that maps can be parsed")
+{
+    writeFile("foo.cfg", "\nfooValue \"a\"\nfooMap{\"foo\"} 1336\nfooMap{\"bar\"} 1337\n");
+    FooConfig config(readConfig("foo.cfg"));
+    ASSERT_EQUAL("a", config.fooValue);
+    ASSERT_EQUAL(2u, config.fooMap.size());
+    ASSERT_EQUAL(1336, config.fooMap.at("foo"));
+    ASSERT_EQUAL(1337, config.fooMap.at("bar"));
+}
+
+TEST("handles quotes for bool values") {
+    std::vector<vespalib::string> payload;
+    payload.push_back("foo \"true\"");
+    payload.push_back("bar \"123\"");
+    payload.push_back("baz \"1234\"");
+    payload.push_back("quux \"3.2\"");
+    bool b(ConfigParser::parse<bool>("foo", payload));
+    int32_t i(ConfigParser::parse<int32_t>("bar", payload));
+    int64_t l(ConfigParser::parse<int64_t>("baz", payload));
+    double d(ConfigParser::parse<double>("quux", payload));
+    EXPECT_EQUAL(true, b);
+    EXPECT_EQUAL(123, i);
+    EXPECT_EQUAL(1234, l);
+    EXPECT_APPROX(3.2, d, 0.001);
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/configretriever/.gitignore b/config/src/tests/configretriever/.gitignore
new file mode 100644
index 00000000000..a5e6241747d
--- /dev/null
+++ b/config/src/tests/configretriever/.gitignore
@@ -0,0 +1,8 @@
+/config-bar.cpp
+/config-bar.h
+/config-bootstrap.cpp
+/config-bootstrap.h
+/config-foo.cpp
+/config-foo.h
+/testsnapshot.txt
+config_configretriever_test_app
diff --git a/config/src/tests/configretriever/CMakeLists.txt b/config/src/tests/configretriever/CMakeLists.txt
new file mode 100644
index 00000000000..5c0d8152734
--- /dev/null
+++ b/config/src/tests/configretriever/CMakeLists.txt
@@ -0,0 +1,11 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_configretriever_test_app
+    SOURCES
+    configretriever.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_configretriever_test_app COMMAND config_configretriever_test_app)
+vespa_generate_config(config_configretriever_test_app ../../test/resources/configdefinitions/bootstrap.def)
+vespa_generate_config(config_configretriever_test_app ../../test/resources/configdefinitions/foo.def)
+vespa_generate_config(config_configretriever_test_app ../../test/resources/configdefinitions/bar.def)
diff --git a/config/src/tests/configretriever/configretriever.cpp b/config/src/tests/configretriever/configretriever.cpp
new file mode 100644
index 00000000000..9b191512e0e
--- /dev/null
+++ b/config/src/tests/configretriever/configretriever.cpp
@@ -0,0 +1,444 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP("configretriever");
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/vespalib/data/slime/slime.h>
+#include <vespa/config/config.h>
+#include <vespa/config/print.h>
+#include <vespa/config/retriever/configretriever.h>
+#include <vespa/config/retriever/simpleconfigretriever.h>
+#include <vespa/config/retriever/simpleconfigurer.h>
+#include <vespa/config/common/configholder.h>
+#include <vespa/config/subscription/configsubscription.h>
+#include "config-bootstrap.h"
+#include "config-foo.h"
+#include "config-bar.h"
+#include <atomic>
+
+using namespace config;
+using namespace std;
+using namespace vespalib::slime;
+using namespace vespalib;
+
+struct ComponentFixture {
+    typedef std::shared_ptr<ComponentFixture> SP;
+    FooConfigBuilder fooBuilder;
+    BarConfigBuilder barBuilder;
+};
+
+struct ConfigTestFixture {
+    const std::string configId;
+    BootstrapConfigBuilder bootstrapBuilder;
+    map<std::string, ComponentFixture::SP> componentConfig;
+    ConfigSet set;
+    IConfigContext::SP context;
+    int idcounter;
+
+    ConfigTestFixture(const std::string & id)
+        : configId(id),
+          bootstrapBuilder(),
+          componentConfig(),
+          set(),
+          context(new ConfigContext(set)),
+          idcounter(-1)
+    {
+        set.addBuilder(configId, &bootstrapBuilder);
+    }
+
+    void addComponent(const std::string & name, const std::string & fooValue, const std::string & barValue)
+    {
+        BootstrapConfigBuilder::Component component;
+        component.name = name;
+        component.configid = configId + "/" + name;
+        bootstrapBuilder.component.push_back(component);
+
+        ComponentFixture::SP fixture(new ComponentFixture());
+        fixture->fooBuilder.fooValue = fooValue;
+        fixture->barBuilder.barValue = barValue;
+        set.addBuilder(component.configid, &fixture->fooBuilder);
+        set.addBuilder(component.configid, &fixture->barBuilder);
+        componentConfig[name] = fixture;
+    }
+
+    void removeComponent(const std::string & name)
+    {
+        for (BootstrapConfigBuilder::ComponentVector::iterator it(bootstrapBuilder.component.begin()),
+                                                               mt(bootstrapBuilder.component.end()); it != mt; it++) {
+            if ((*it).name.compare(name) == 0) {
+                bootstrapBuilder.component.erase(it);
+                break;
+            }
+        }
+    }
+
+    bool configEqual(const std::string & name, const FooConfig & fooConfig) {
+        ComponentFixture::SP fixture(componentConfig[name]);
+        return (fixture->fooBuilder == fooConfig);
+    }
+
+    bool configEqual(const std::string & name, const BarConfig & barConfig) {
+        ComponentFixture::SP fixture(componentConfig[name]);
+        return (fixture->barBuilder == barConfig);
+    }
+
+    bool configEqual(const BootstrapConfig & bootstrapConfig) {
+        return (bootstrapBuilder == bootstrapConfig);
+    }
+
+    void reload() { context->reload(); }
+};
+
+struct SimpleSetup
+{
+    ConfigKeySet bootstrapKeys;
+    ConfigKeySet componentKeys;
+    std::unique_ptr<ConfigRetriever> retriever;
+    SimpleSetup(ConfigTestFixture & f1)
+        : bootstrapKeys(), componentKeys(), retriever()
+    {
+        f1.addComponent("c1", "foo1", "bar1");
+        bootstrapKeys.add<BootstrapConfig>(f1.configId);
+        retriever.reset(new ConfigRetriever(bootstrapKeys, f1.context));
+    }
+
+};
+
+struct MySource : public Source
+{
+    void getConfig() { }
+    void close() { }
+    void reload(int64_t gen) { (void) gen; }
+};
+
+struct SubscriptionFixture
+{
+    IConfigHolder::SP holder;
+    ConfigSubscription::SP sub;
+    SubscriptionFixture(const ConfigKey & key, const ConfigValue value)
+        : holder(new ConfigHolder()),
+          sub(new ConfigSubscription(0, key, holder, Source::UP(new MySource())))
+    {
+        holder->handle(ConfigUpdate::UP(new ConfigUpdate(value, 3, 3)));
+        ASSERT_TRUE(sub->nextUpdate(0, 0));
+        sub->flip();
+    }
+};
+
+
+namespace {
+
+class FixedPayload : public protocol::Payload {
+public:
+    const Inspector & getSlimePayload() const
+    {
+        return _data.get();
+    }
+
+    Slime & getData() {
+        return _data;
+    }
+private:
+    Slime _data;
+};
+
+}
+
+ConfigValue createKeyValueV2(const vespalib::string & key, const vespalib::string & value)
+{
+    FixedPayload * payload = new FixedPayload();
+    payload->getData().setObject().setString(key, Memory(value));
+    return ConfigValue(PayloadPtr(payload), "");
+}
+
+
+TEST_F("require that basic retriever usage works", ConfigTestFixture("myid")) {
+    f1.addComponent("c1", "foo1", "bar1");
+    f1.addComponent("c2", "foo2", "bar2");
+
+    ConfigKeySet keys;
+    keys.add<BootstrapConfig>(f1.configId);
+
+    ConfigRetriever ret(keys, f1.context);
+    ConfigSnapshot configs = ret.getBootstrapConfigs();
+    ASSERT_EQUAL(1u, configs.size());
+
+    std::unique_ptr<BootstrapConfig> bootstrapConfig = configs.getConfig<BootstrapConfig>(f1.configId);
+    ASSERT_TRUE(f1.configEqual(*bootstrapConfig));
+
+    {
+        ConfigKeySet componentKeys;
+        for (size_t i = 0; i < bootstrapConfig->component.size(); i++) {
+            const vespalib::string & configId(bootstrapConfig->component[i].configid);
+            componentKeys.add<FooConfig>(configId);
+        }
+        configs = ret.getConfigs(componentKeys);
+        ASSERT_EQUAL(2u, configs.size());
+        ASSERT_TRUE(f1.configEqual("c1", *configs.getConfig<FooConfig>(bootstrapConfig->component[0].configid)));
+        ASSERT_TRUE(f1.configEqual("c2", *configs.getConfig<FooConfig>(bootstrapConfig->component[1].configid)));
+    }
+    {
+        ConfigKeySet componentKeys;
+        for (size_t i = 0; i < bootstrapConfig->component.size(); i++) {
+            const vespalib::string & configId(bootstrapConfig->component[i].configid);
+            componentKeys.add<BarConfig>(configId);
+        }
+        configs = ret.getConfigs(componentKeys);
+        ASSERT_EQUAL(2u, configs.size());
+        ASSERT_TRUE(f1.configEqual("c1", *configs.getConfig<BarConfig>(bootstrapConfig->component[0].configid)));
+        ASSERT_TRUE(f1.configEqual("c2", *configs.getConfig<BarConfig>(bootstrapConfig->component[1].configid)));
+    }
+    {
+        ConfigKeySet componentKeys;
+        for (size_t i = 0; i < bootstrapConfig->component.size(); i++) {
+            const vespalib::string & configId(bootstrapConfig->component[i].configid);
+            componentKeys.add<FooConfig>(configId);
+            componentKeys.add<BarConfig>(configId);
+        }
+        configs = ret.getConfigs(componentKeys);
+
+        ASSERT_EQUAL(4u, configs.size());
+        ASSERT_TRUE(f1.configEqual("c1", *configs.getConfig<FooConfig>(bootstrapConfig->component[0].configid)));
+        ASSERT_TRUE(f1.configEqual("c1", *configs.getConfig<BarConfig>(bootstrapConfig->component[0].configid)));
+        ASSERT_TRUE(f1.configEqual("c2", *configs.getConfig<FooConfig>(bootstrapConfig->component[1].configid)));
+        ASSERT_TRUE(f1.configEqual("c2", *configs.getConfig<BarConfig>(bootstrapConfig->component[1].configid)));
+    }
+}
+
+TEST("require that SimpleConfigRetriever usage works") {
+    ConfigSet set;
+    FooConfigBuilder fooBuilder;
+    BarConfigBuilder barBuilder;
+    fooBuilder.fooValue = "barz";
+    barBuilder.barValue = "fooz";
+    set.addBuilder("id", &fooBuilder);
+    set.addBuilder("id", &barBuilder);
+    IConfigContext::SP ctx(new ConfigContext(set));
+    ConfigKeySet sub;
+    sub.add<FooConfig>("id");
+    sub.add<BarConfig>("id");
+    SimpleConfigRetriever retr(sub, ctx);
+    ConfigSnapshot snap = retr.getConfigs();
+    ASSERT_FALSE(snap.empty());
+    ASSERT_EQUAL(2u, snap.size());
+    std::unique_ptr<FooConfig> foo = snap.getConfig<FooConfig>("id");
+    std::unique_ptr<BarConfig> bar = snap.getConfig<BarConfig>("id");
+    ASSERT_EQUAL("barz", foo->fooValue);
+    ASSERT_EQUAL("fooz", bar->barValue);
+}
+
+class ConfigurableFixture : public SimpleConfigurable
+{
+public:
+    /**
+     * Note that due to some bug in gcc 5.2 this file must be compiled with
+     * -fno-tree-vrp which turns off some optimization. Or you can reorder the menbers here
+     * and put 'snap' after the atomics.
+     */
+    ConfigurableFixture() __attribute__((noinline));
+    virtual ~ConfigurableFixture() __attribute__((noinline));
+    void configure(const ConfigSnapshot & snapshot) override {
+        (void) snapshot;
+        if (throwException) {
+            throw ConfigRuntimeException("foo");
+        }
+        snap = snapshot;
+        configured = true;
+    }
+    bool waitUntilConfigured(int64_t timeoutInMillis) {
+        FastOS_Time timer;
+        timer.SetNow();
+        while (timer.MilliSecsToNow() < timeoutInMillis) {
+            if (configured) {
+                return true;
+            }
+            FastOS_Thread::Sleep(200);
+        }
+        return configured;
+    }
+
+    ConfigSnapshot snap;
+    std::atomic<bool> configured;
+    std::atomic<bool> throwException;
+};
+
+ConfigurableFixture::ConfigurableFixture() :
+    configured(false),
+    throwException(false)
+{
+}
+
+ConfigurableFixture::~ConfigurableFixture()
+{
+}
+
+TEST_F("require that SimpleConfigurer usage works", ConfigurableFixture()) {
+    ConfigSet set;
+    FooConfigBuilder fooBuilder;
+    BarConfigBuilder barBuilder;
+    fooBuilder.fooValue = "barz";
+    barBuilder.barValue = "fooz";
+    set.addBuilder("id", &fooBuilder);
+    set.addBuilder("id", &barBuilder);
+    IConfigContext::SP ctx(new ConfigContext(set));
+    ConfigKeySet sub;
+    sub.add<FooConfig>("id");
+    sub.add<BarConfig>("id");
+    SimpleConfigurer configurer(SimpleConfigRetriever::UP(new SimpleConfigRetriever(sub, ctx)), &f1);
+    configurer.start();
+    ASSERT_FALSE(f1.snap.empty());
+    ASSERT_EQUAL(2u, f1.snap.size());
+    ConfigSnapshot snap = f1.snap;
+    std::unique_ptr<FooConfig> foo = snap.getConfig<FooConfig>("id");
+    std::unique_ptr<BarConfig> bar = snap.getConfig<BarConfig>("id");
+    ASSERT_EQUAL("barz", foo->fooValue);
+    ASSERT_EQUAL("fooz", bar->barValue);
+
+    f1.configured = false;
+    fooBuilder.fooValue = "bimz";
+    ctx->reload();
+    ASSERT_TRUE(f1.waitUntilConfigured(60000));
+    snap = f1.snap;
+    foo = snap.getConfig<FooConfig>("id");
+    ASSERT_EQUAL("bimz", foo->fooValue);
+    configurer.close();
+    fooBuilder.fooValue = "bamz";
+    f1.configured = false;
+    ctx->reload();
+    ASSERT_FALSE(f1.waitUntilConfigured(2000));
+
+    SimpleConfigurer configurer2(SimpleConfigRetriever::UP(new SimpleConfigRetriever(sub, ctx)), &f1);
+    f1.throwException = true;
+    ASSERT_EXCEPTION(configurer2.start(), ConfigRuntimeException, "foo");
+    configurer2.close();
+}
+
+TEST("require that variadic templates can be used to create key sets") {
+    ConfigKeySet set;
+    set.add<FooConfig, BarConfig, BootstrapConfig>("myid");
+    ASSERT_EQUAL(3u, set.size());
+}
+
+TEST_FF("require that getBootstrapConfigs returns empty snapshot when closed", ConfigTestFixture("myid"), SimpleSetup(f1)) {
+    ConfigSnapshot configs = f2.retriever->getBootstrapConfigs();
+    ASSERT_TRUE(!configs.empty());
+    ASSERT_FALSE(f2.retriever->isClosed());
+    f2.retriever->close();
+    ASSERT_TRUE(f2.retriever->isClosed());
+    configs = f2.retriever->getBootstrapConfigs();
+    ASSERT_TRUE(configs.empty());
+}
+
+TEST_FF("require that getConfigs throws exception when closed", ConfigTestFixture("myid"), SimpleSetup(f1)) {
+    ConfigSnapshot configs = f2.retriever->getBootstrapConfigs();
+    std::unique_ptr<BootstrapConfig> bootstrapConfig = configs.getConfig<BootstrapConfig>(f1.configId);
+    ConfigKeySet componentKeys;
+    for (size_t i = 0; i < bootstrapConfig->component.size(); i++) {
+        const vespalib::string & configId(bootstrapConfig->component[i].configid);
+        componentKeys.add<FooConfig>(configId);
+        componentKeys.add<BarConfig>(configId);
+    }
+    ASSERT_FALSE(f2.retriever->isClosed());
+    f2.retriever->close();
+    ASSERT_TRUE(f2.retriever->isClosed());
+    configs = f2.retriever->getConfigs(componentKeys);
+    ASSERT_TRUE(configs.empty());
+}
+
+
+TEST_FF("require that snapshots throws exception if invalid key", ConfigTestFixture("myid"), SimpleSetup(f1)) {
+    f1.addComponent("c3", "foo3", "bar3");
+    ConfigSnapshot snap1 = f2.retriever->getBootstrapConfigs();
+    ASSERT_FALSE(snap1.hasConfig<BarConfig>("doesnotexist"));
+    ASSERT_EXCEPTION(snap1.getConfig<BarConfig>("doesnotexist"), IllegalConfigKeyException, "Unable to find config for key name=bar,namespace=config,configId=doesnotexist");
+    ASSERT_EXCEPTION(snap1.isChanged<BarConfig>("doesnotexist", 0), IllegalConfigKeyException, "Unable to find config for key name=bar,namespace=config,configId=doesnotexist");
+    ASSERT_TRUE(snap1.hasConfig<BootstrapConfig>("myid"));
+}
+
+TEST_FF("require that snapshots can be ignored", ConfigTestFixture("myid"), SimpleSetup(f1)) {
+    f1.addComponent("c3", "foo3", "bar3");
+    ConfigSnapshot snap1 = f2.retriever->getBootstrapConfigs();
+    int64_t lastGen = snap1.getGeneration();
+    f1.reload();
+    ASSERT_EQUAL(lastGen, snap1.getGeneration());
+    ConfigSnapshot snap2 = f2.retriever->getBootstrapConfigs();
+    ASSERT_EQUAL(snap2.getGeneration(), 2);
+    ASSERT_TRUE(snap2.isChanged<BootstrapConfig>("myid", lastGen));
+    ASSERT_FALSE(snap2.isChanged<BootstrapConfig>("myid", lastGen + 1));
+    f1.reload();
+    ConfigSnapshot snap3 = f2.retriever->getBootstrapConfigs();
+    ASSERT_TRUE(snap3.isChanged<BootstrapConfig>("myid", lastGen));
+    ASSERT_FALSE(snap3.isChanged<BootstrapConfig>("myid", lastGen + 1));
+}
+
+TEST_FFF("require that snapshots can produce subsets", SubscriptionFixture(ConfigKey::create<FooConfig>("id"), createKeyValueV2("fooValue", "bar")),
+                                                       SubscriptionFixture(ConfigKey::create<BarConfig>("id"), createKeyValueV2("barValue", "foo")),
+                                                       ConfigSnapshot::SubscriptionList()) {
+    f3.push_back(f1.sub);
+    f3.push_back(f2.sub);
+    ConfigSnapshot parent(f3, 3);
+    ASSERT_FALSE(parent.empty());
+    ASSERT_EQUAL(3, parent.getGeneration());
+    ASSERT_EQUAL(2u, parent.size());
+
+    ConfigSnapshot subset1(parent.subset(ConfigKeySet().add<FooConfig>("id")));
+    ASSERT_FALSE(subset1.empty());
+    ASSERT_EQUAL(3, subset1.getGeneration());
+    ASSERT_EQUAL(1u, subset1.size());
+    std::unique_ptr<FooConfig> cfg1(subset1.getConfig<FooConfig>("id"));
+    ASSERT_TRUE(cfg1.get() != NULL);
+
+    ConfigSnapshot subset2(parent.subset(ConfigKeySet().add<BarConfig>("id")));
+    ASSERT_FALSE(subset2.empty());
+    ASSERT_EQUAL(3, subset2.getGeneration());
+    ASSERT_EQUAL(1u, subset2.size());
+    std::unique_ptr<BarConfig> cfg2(subset2.getConfig<BarConfig>("id"));
+    ASSERT_TRUE(cfg2.get() != NULL);
+
+    ConfigSnapshot subset3(parent.subset(ConfigKeySet().add<BarConfig>("doesnotexist")));
+    ASSERT_TRUE(subset3.empty());
+    ASSERT_EQUAL(3, subset3.getGeneration());
+    ASSERT_EQUAL(0u, subset3.size());
+
+    ConfigSnapshot subset4(parent.subset(ConfigKeySet().add<BarConfig>("doesnotexist").add<FooConfig>("id").add<FooConfig>("nosuchthing").add<BarConfig>("id").add<BarConfig>("nothere")));
+    ASSERT_FALSE(subset4.empty());
+    ASSERT_EQUAL(3, subset4.getGeneration());
+    ASSERT_EQUAL(2u, subset4.size());
+    cfg1 = subset4.getConfig<FooConfig>("id");
+    ASSERT_TRUE(cfg1.get() != NULL);
+    cfg2 = subset4.getConfig<BarConfig>("id");
+    ASSERT_TRUE(cfg2.get() != NULL);
+}
+
+TEST_FFF("require that snapshots can be serialized", SubscriptionFixture(ConfigKey::create<FooConfig>("id"), createKeyValueV2("fooValue", "bar")),
+                                                     SubscriptionFixture(ConfigKey::create<BarConfig>("id"), createKeyValueV2("barValue", "foo")),
+                                                     ConfigSnapshot::SubscriptionList()) {
+    f3.push_back(f1.sub);
+    f3.push_back(f2.sub);
+    ConfigSnapshot parent(f3, 3);
+
+    typedef std::shared_ptr<ConfigSnapshotWriter> WSP;
+    typedef std::shared_ptr<ConfigSnapshotReader> RSP;
+    typedef std::pair<WSP, RSP> SerializePair;
+    typedef std::vector<SerializePair> Vec;
+    Vec vec;
+    vespalib::asciistream ss;
+    vec.push_back(SerializePair(WSP(new FileConfigSnapshotWriter("testsnapshot.txt")),
+                                RSP(new FileConfigSnapshotReader("testsnapshot.txt"))));
+    vec.push_back(SerializePair(WSP(new AsciiConfigSnapshotWriter(ss)),
+                                RSP(new AsciiConfigSnapshotReader(ss))));
+    for (Vec::iterator it(vec.begin()), mt(vec.end()); it != mt; it++) {
+        ASSERT_TRUE(it->first->write(parent));
+        ConfigSnapshot deser(it->second->read());
+        ASSERT_EQUAL(parent.getGeneration(), deser.getGeneration());
+        ASSERT_EQUAL(parent.size(), deser.size());
+        ASSERT_TRUE(deser.hasConfig<FooConfig>("id"));
+        ASSERT_TRUE(deser.hasConfig<BarConfig>("id"));
+        std::unique_ptr<FooConfig> foo = deser.getConfig<FooConfig>("id");
+        std::unique_ptr<BarConfig> bar = deser.getConfig<BarConfig>("id");
+        ASSERT_EQUAL("bar", foo->fooValue);
+        ASSERT_EQUAL("foo", bar->barValue);
+    }
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/configuri/.gitignore b/config/src/tests/configuri/.gitignore
new file mode 100644
index 00000000000..87df7752465
--- /dev/null
+++ b/config/src/tests/configuri/.gitignore
@@ -0,0 +1,3 @@
+/config-my.cpp
+/config-my.h
+config_configuri_test_app
diff --git a/config/src/tests/configuri/CMakeLists.txt b/config/src/tests/configuri/CMakeLists.txt
new file mode 100644
index 00000000000..10fcac86c76
--- /dev/null
+++ b/config/src/tests/configuri/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_configuri_test_app
+    SOURCES
+    configuri_test.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_configuri_test_app COMMAND config_configuri_test_app)
+vespa_generate_config(config_configuri_test_app ../../test/resources/configdefinitions/my.def)
diff --git a/config/src/tests/configuri/configuri_test.cpp b/config/src/tests/configuri/configuri_test.cpp
new file mode 100644
index 00000000000..83b99542ce4
--- /dev/null
+++ b/config/src/tests/configuri/configuri_test.cpp
@@ -0,0 +1,58 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/config.h>
+#include "config-my.h"
+
+using namespace config;
+
+namespace {
+
+void assertConfigId(const std::string & expected, const ConfigUri & uri) {
+    ASSERT_EQUAL(expected, uri.getConfigId());
+}
+
+}
+TEST("Require that URI can be created from const char *") {
+    assertConfigId("foo/bar", ConfigUri("foo/bar"));
+    assertConfigId("myfile", ConfigUri("file:myfile.cfg"));
+    assertConfigId("", ConfigUri("raw:myraw"));
+    assertConfigId("", ConfigUri("dir:."));
+}
+
+TEST("Require that URI can be created from std::string") {
+    assertConfigId("foo/bar", ConfigUri(std::string("foo/bar")));
+    assertConfigId("myfile", ConfigUri(std::string("file:myfile.cfg")));
+    assertConfigId("", ConfigUri(std::string("raw:myraw")));
+    assertConfigId("", ConfigUri(std::string("dir:.")));
+}
+
+TEST("Require that URI can be created from vespalib::string") {
+    assertConfigId("foo/bar", ConfigUri(vespalib::string("foo/bar")));
+    assertConfigId("myfile", ConfigUri(vespalib::string("file:myfile.cfg")));
+    assertConfigId("", ConfigUri(vespalib::string("raw:myraw")));
+    assertConfigId("", ConfigUri(vespalib::string("dir:.")));
+}
+
+TEST("Require that URI can be created from  instance") {
+    MyConfigBuilder b;
+    b.myField = "rabarbra";
+    ConfigUri uri(ConfigUri::createFromInstance(b));
+    ConfigSubscriber subscriber(uri.getContext());
+    ConfigHandle<MyConfig>::UP handle =
+        subscriber.subscribe<MyConfig>(uri.getConfigId());
+    ASSERT_TRUE(subscriber.nextConfig(0));
+    ASSERT_TRUE(handle->isChanged());
+    std::unique_ptr<MyConfig> cfg = handle->getConfig();
+    ASSERT_EQUAL(b.myField, cfg->myField);
+
+}
+
+TEST_F("Require that URI can be \"forked\"", IConfigContext::SP(new ConfigContext())) {
+    assertConfigId("baz", ConfigUri("foo/bar").createWithNewId("baz"));
+    ConfigUri parent("foo", f1);
+    ConfigUri child = parent.createWithNewId("baz");
+    ASSERT_TRUE(parent.getContext().get() == child.getContext().get());
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/failover/.gitignore b/config/src/tests/failover/.gitignore
new file mode 100644
index 00000000000..8e4e371539f
--- /dev/null
+++ b/config/src/tests/failover/.gitignore
@@ -0,0 +1,3 @@
+/config-my.cpp
+/config-my.h
+config_failover_test_app
diff --git a/config/src/tests/failover/CMakeLists.txt b/config/src/tests/failover/CMakeLists.txt
new file mode 100644
index 00000000000..aa5ab803bc5
--- /dev/null
+++ b/config/src/tests/failover/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_failover_test_app
+    SOURCES
+    failover.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_failover_test_app COMMAND config_failover_test_app)
+vespa_generate_config(config_failover_test_app ../../test/resources/configdefinitions/my.def)
diff --git a/config/src/tests/failover/failover.cpp b/config/src/tests/failover/failover.cpp
new file mode 100644
index 00000000000..baaae8ba19a
--- /dev/null
+++ b/config/src/tests/failover/failover.cpp
@@ -0,0 +1,356 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP("failover");
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/common/misc.h>
+#include <vespa/config/frt/protocol.h>
+#include <vespa/config/config.h>
+#include <vespa/fnet/frt/frt.h>
+#include "config-my.h"
+#include <vespa/vespalib/data/slime/slime.h>
+
+using namespace config;
+using vespalib::Barrier;
+using namespace config::protocol::v2;
+using namespace vespalib::slime;
+using namespace vespalib;
+
+namespace {
+
+int get_port(const vespalib::string &spec) {
+    const char *port = (spec.data() + spec.size());
+    while ((port > spec.data()) && (port[-1] >= '0') && (port[-1] <= '9')) {
+        --port;
+    }
+    return atoi(port);
+}
+
+const vespalib::string requestTypes = "s";
+const vespalib::string responseTypes = "sx";
+
+struct RPCServer : public FRT_Invokable {
+    FRT_Supervisor * supervisor;
+    vespalib::Barrier barrier;
+    int64_t gen;
+
+    RPCServer() : supervisor(NULL), barrier(2), gen(1) { }
+
+    void init(FRT_Supervisor * s) {
+        FRT_ReflectionBuilder rb(s);
+        rb.DefineMethod("config.v3.getConfig", requestTypes.c_str(), responseTypes.c_str(), true,
+                        FRT_METHOD(RPCServer::getConfig), this);
+    }
+
+    void getConfig(FRT_RPCRequest * req)
+    {
+        Slime slime;
+        Cursor & root(slime.setObject());
+        root.setLong(RESPONSE_VERSION, 3);
+        root.setString(RESPONSE_DEF_NAME, Memory(MyConfig::CONFIG_DEF_NAME));
+        root.setString(RESPONSE_DEF_NAMESPACE, Memory(MyConfig::CONFIG_DEF_NAMESPACE));
+        root.setString(RESPONSE_DEF_MD5, Memory(MyConfig::CONFIG_DEF_MD5));
+        Cursor &info = root.setObject("compressionInfo");
+        info.setString("compressionType", "UNCOMPRESSED");
+        info.setString("uncompressedSize", "0");
+        root.setString(RESPONSE_CONFIGID, "myId");
+        root.setString(RESPONSE_CLIENT_HOSTNAME, "myhost");
+        root.setString(RESPONSE_CONFIG_MD5, "md5");
+        root.setLong(RESPONSE_CONFIG_GENERATION, gen);
+        root.setObject(RESPONSE_TRACE);
+        Slime payload;
+        payload.setObject().setString("myField", "myval");
+
+        FRT_Values & ret = *req->GetReturn();
+        SimpleBuffer buf;
+        JsonFormat::encode(slime, buf, false);
+        ret.AddString(buf.get().make_string().c_str());
+
+        SimpleBuffer pbuf;
+        JsonFormat::encode(payload, pbuf, false);
+        vespalib::string d = pbuf.get().make_string();
+        ret.AddData(d.c_str(), d.size());
+        LOG(info, "Answering...");
+    }
+    void wait() {
+        barrier.await();
+    }
+    void reload() { gen++; }
+};
+
+
+void verifyConfig(std::unique_ptr<MyConfig> config)
+{
+    ASSERT_TRUE(config.get() != NULL);
+    ASSERT_EQUAL("myval", config->myField);
+}
+
+struct ServerFixture {
+    typedef vespalib::LinkedPtr<ServerFixture> LP;
+    FRT_Supervisor * supervisor;
+    RPCServer server;
+    Barrier b;
+    const vespalib::string listenSpec;
+    ServerFixture(const vespalib::string & ls)
+        : supervisor(NULL),
+          server(),
+          b(2),
+          listenSpec(ls)
+    {
+    }
+
+    void wait()
+    {
+        b.await();
+    }
+
+    void start()
+    {
+        supervisor = new FRT_Supervisor();
+        server.init(supervisor);
+        supervisor->Listen(get_port(listenSpec));
+        wait(); // Wait until test runner signals we can start
+        supervisor->Main();
+        wait(); // Signalling that we have shut down
+        wait(); // Wait for signal saying that supervisor is deleted
+    }
+
+    void stop()
+    {
+        if (supervisor != NULL) {
+            supervisor->ShutDown(true);
+            wait(); // Wait for supervisor to shut down
+            delete supervisor;
+            supervisor = NULL;
+            wait(); // Signal that we are done and start can return.
+        }
+    }
+
+    ~ServerFixture() { stop(); }
+};
+
+struct NetworkFixture {
+    std::vector<ServerFixture::LP> serverList;
+    ServerSpec spec;
+    bool running;
+    NetworkFixture(const std::vector<vespalib::string> & serverSpecs)
+        : spec(serverSpecs), running(true)
+    {
+        for (size_t i = 0; i < serverSpecs.size(); i++) {
+            serverList.push_back(ServerFixture::LP(new ServerFixture(serverSpecs[i])));
+        }
+    }
+    void start(size_t i) {
+        serverList[i]->start();
+    }
+    void wait(size_t i) {
+        serverList[i]->wait();
+    }
+    void waitAll() {
+        for (size_t i = 0; i < serverList.size(); i++) {
+            serverList[i]->wait();
+        }
+    }
+    void run(size_t i) {
+        while (running) {
+            serverList[i]->start();
+        }
+    }
+    void stopAll() {
+        running = false;
+        for (size_t i = 0; i < serverList.size(); i++) {
+            serverList[i]->stop();
+        }
+    }
+    void stop(size_t i) {
+        serverList[i]->stop();
+    }
+    void reload() {
+        for (size_t i = 0; i < serverList.size(); i++) {
+            serverList[i]->server.reload();
+        }
+    }
+};
+
+
+TimingValues testTimingValues(
+    500,  // successTimeout
+    500,  // errorTimeout
+    500,   // initialTimeout
+    400,  // unsubscribeTimeout
+    0,     // fixedDelay
+    250,   // successDelay
+    250,   // unconfiguredDelay
+    500,   // configuredErrorDelay
+    1,      // maxDelayMultiplier
+    600,  // transientDelay
+    1200); // fatalDelay
+
+struct ConfigCheckFixture {
+    IConfigContext::SP ctx;
+    NetworkFixture & nf;
+
+    ConfigCheckFixture(NetworkFixture & f2)
+        : ctx(new ConfigContext(testTimingValues, f2.spec)),
+          nf(f2)
+    {
+    }
+    void checkSubscribe()
+    {
+        ConfigSubscriber s(ctx);
+        ConfigHandle<MyConfig>::UP handle = s.subscribe<MyConfig>("myId");
+        ASSERT_TRUE(s.nextConfig());
+    }
+    void verifySubscribeFailover(size_t index)
+    {
+        nf.stop(index);
+        checkSubscribe();
+        nf.wait(index);
+    }
+
+    void verifySubscribeFailover(size_t indexA, size_t indexB)
+    {
+        nf.stop(indexA);
+        nf.stop(indexB);
+        checkSubscribe();
+        nf.wait(indexA);
+        nf.wait(indexB);
+    }
+};
+
+struct ConfigReloadFixture {
+    IConfigContext::SP ctx;
+    NetworkFixture & nf;
+    ConfigSubscriber s;
+    ConfigHandle<MyConfig>::UP handle;
+
+    ConfigReloadFixture(NetworkFixture & f2)
+        : ctx(new ConfigContext(testTimingValues, f2.spec)),
+          nf(f2),
+          s(ctx),
+          handle(s.subscribe<MyConfig>("myId"))
+    {
+    }
+
+    void verifyReload()
+    {
+        nf.reload();
+        ASSERT_TRUE(s.nextGeneration());
+        verifyConfig(handle->getConfig());
+    }
+
+    void verifyReloadFailover(size_t index)
+    {
+        nf.stop(index);
+        verifyReload();
+        nf.wait(index);
+    }
+
+    void verifyReloadFailover(size_t indexA, size_t indexB)
+    {
+        nf.stop(indexA);
+        nf.stop(indexB);
+        verifyReload();
+        nf.wait(indexA);
+        nf.wait(indexB);
+    }
+};
+
+struct ThreeServersFixture {
+    std::vector<vespalib::string> specs;
+    ThreeServersFixture() : specs() {
+        specs.push_back("tcp/localhost:18590");
+        specs.push_back("tcp/localhost:18592");
+        specs.push_back("tcp/localhost:18594");
+    }
+};
+
+struct OneServerFixture {
+    std::vector<vespalib::string> specs;
+    OneServerFixture() : specs() {
+        specs.push_back("tcp/localhost:18590");
+    }
+};
+
+}
+
+TEST_MT_FF("require that any node can be down when subscribing",
+             4,
+             ThreeServersFixture(),
+             NetworkFixture(f1.specs))
+{
+    if (thread_id == 0) {
+        ConfigCheckFixture ccf(f2);
+        f2.waitAll();
+        ccf.checkSubscribe();
+        ccf.verifySubscribeFailover(0);
+        ccf.verifySubscribeFailover(1);
+        ccf.verifySubscribeFailover(2);
+        f2.stopAll();
+        TEST_BARRIER();
+    } else {
+        f2.run(thread_id - 1);
+        TEST_BARRIER();
+    }
+}
+/*
+TEST_MT_FF("require that two out of three nodes can be down when subscribing",
+             4,
+             ThreeServersFixture(),
+             NetworkFixture(f1.specs))
+{
+    if (thread_id == 0) {
+        ConfigCheckFixture ccf(f2);
+        f2.waitAll();
+        ccf.checkSubscribe();
+        ccf.verifySubscribeFailover(0, 1);
+        ccf.verifySubscribeFailover(1, 2);
+        ccf.verifySubscribeFailover(0, 2);
+        f2.stopAll();
+        TEST_BARRIER();
+    } else {
+        f2.run(thread_id - 1);
+        TEST_BARRIER();
+    }
+}
+
+TEST_MT_FF("require that any node can be down when waiting for next generation",
+             4,
+             ThreeServersFixture(),
+             NetworkFixture(f1.specs))
+{
+    if (thread_id == 0) {
+        f2.waitAll();
+        ConfigReloadFixture crf(f2);
+        crf.verifyReload();
+        crf.verifyReloadFailover(0);
+        crf.verifyReloadFailover(1);
+        crf.verifyReloadFailover(2);
+        f2.stopAll();
+        TEST_BARRIER();
+    } else { f2.run(thread_id - 1); TEST_BARRIER();
+    }
+}
+
+TEST_MT_FF("require that two out of three nodes can be down when waiting for next generation",
+             4,
+             ThreeServersFixture(),
+             NetworkFixture(f1.specs))
+{
+    if (thread_id == 0) {
+        f2.waitAll();
+        ConfigReloadFixture crf(f2);
+        crf.verifyReload();
+        crf.verifyReloadFailover(0, 1);
+        crf.verifyReloadFailover(1, 2);
+        crf.verifyReloadFailover(0, 2);
+        f2.stopAll();
+        TEST_BARRIER();
+    } else {
+        f2.run(thread_id - 1);
+        TEST_BARRIER();
+    }
+}
+*/
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/file_subscription/.gitignore b/config/src/tests/file_subscription/.gitignore
new file mode 100644
index 00000000000..7dd29b02329
--- /dev/null
+++ b/config/src/tests/file_subscription/.gitignore
@@ -0,0 +1,11 @@
+/config-my.cpp
+/config-my.h
+/config-bar.cpp
+/config-bar.h
+/config-foo.cpp
+/config-foo.h
+/config-foobar.cpp
+/config-foobar.h
+/config-foodefault.cpp
+/config-foodefault.h
+config_file_subscription_test_app
diff --git a/config/src/tests/file_subscription/CMakeLists.txt b/config/src/tests/file_subscription/CMakeLists.txt
new file mode 100644
index 00000000000..f582732ffb2
--- /dev/null
+++ b/config/src/tests/file_subscription/CMakeLists.txt
@@ -0,0 +1,13 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_file_subscription_test_app
+    SOURCES
+    file_subscription.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_file_subscription_test_app COMMAND config_file_subscription_test_app)
+vespa_generate_config(config_file_subscription_test_app ../../test/resources/configdefinitions/my.def)
+vespa_generate_config(config_file_subscription_test_app ../../test/resources/configdefinitions/foo.def)
+vespa_generate_config(config_file_subscription_test_app ../../test/resources/configdefinitions/bar.def)
+vespa_generate_config(config_file_subscription_test_app ../../test/resources/configdefinitions/foobar.def)
+vespa_generate_config(config_file_subscription_test_app ../../test/resources/configdefinitions/foodefault.def)
diff --git a/config/src/tests/file_subscription/cfgdir/bar.cfg b/config/src/tests/file_subscription/cfgdir/bar.cfg
new file mode 100644
index 00000000000..cd7ce3a73ec
--- /dev/null
+++ b/config/src/tests/file_subscription/cfgdir/bar.cfg
@@ -0,0 +1 @@
+barValue "barbar"
diff --git a/config/src/tests/file_subscription/cfgdir/foo.cfg b/config/src/tests/file_subscription/cfgdir/foo.cfg
new file mode 100644
index 00000000000..288a1571758
--- /dev/null
+++ b/config/src/tests/file_subscription/cfgdir/foo.cfg
@@ -0,0 +1 @@
+fooValue "foofoo"
diff --git a/config/src/tests/file_subscription/cfgdir2/bar.cfg b/config/src/tests/file_subscription/cfgdir2/bar.cfg
new file mode 100644
index 00000000000..cd7ce3a73ec
--- /dev/null
+++ b/config/src/tests/file_subscription/cfgdir2/bar.cfg
@@ -0,0 +1 @@
+barValue "barbar"
diff --git a/config/src/tests/file_subscription/cfgdir2/foobar.cfg b/config/src/tests/file_subscription/cfgdir2/foobar.cfg
new file mode 100644
index 00000000000..e938175a509
--- /dev/null
+++ b/config/src/tests/file_subscription/cfgdir2/foobar.cfg
@@ -0,0 +1 @@
+fooBarValue "foobarlol"
diff --git a/config/src/tests/file_subscription/cfgdir3/bar.bar.cfg b/config/src/tests/file_subscription/cfgdir3/bar.bar.cfg
new file mode 100644
index 00000000000..5246bbb392d
--- /dev/null
+++ b/config/src/tests/file_subscription/cfgdir3/bar.bar.cfg
@@ -0,0 +1 @@
+barValue "foobarlol"
diff --git a/config/src/tests/file_subscription/cfgdir3/bar.foo.cfg b/config/src/tests/file_subscription/cfgdir3/bar.foo.cfg
new file mode 100644
index 00000000000..cd7ce3a73ec
--- /dev/null
+++ b/config/src/tests/file_subscription/cfgdir3/bar.foo.cfg
@@ -0,0 +1 @@
+barValue "barbar"
diff --git a/config/src/tests/file_subscription/cfgemptyfile/bar.cfg b/config/src/tests/file_subscription/cfgemptyfile/bar.cfg
new file mode 100644
index 00000000000..cd7ce3a73ec
--- /dev/null
+++ b/config/src/tests/file_subscription/cfgemptyfile/bar.cfg
@@ -0,0 +1 @@
+barValue "barbar"
diff --git a/config/src/tests/file_subscription/cfgemptyfile/foodefault.cfg b/config/src/tests/file_subscription/cfgemptyfile/foodefault.cfg
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/tests/file_subscription/cfgemptyfile/foodefault.cfg
diff --git a/config/src/tests/file_subscription/cfgnonexistingfile/bar.cfg b/config/src/tests/file_subscription/cfgnonexistingfile/bar.cfg
new file mode 100644
index 00000000000..cd7ce3a73ec
--- /dev/null
+++ b/config/src/tests/file_subscription/cfgnonexistingfile/bar.cfg
@@ -0,0 +1 @@
+barValue "barbar"
diff --git a/config/src/tests/file_subscription/file_subscription.cpp b/config/src/tests/file_subscription/file_subscription.cpp
new file mode 100644
index 00000000000..4b2c84281e9
--- /dev/null
+++ b/config/src/tests/file_subscription/file_subscription.cpp
@@ -0,0 +1,205 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/config.h>
+#include <vespa/config/common/configholder.h>
+#include <vespa/config/file/filesource.h>
+#include <vespa/vespalib/util/sync.h>
+#include <fstream>
+#include <config-my.h>
+#include <config-foo.h>
+#include <config-foodefault.h>
+#include <config-bar.h>
+#include <config-foobar.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".filesubscription_test");
+
+using namespace config;
+
+namespace {
+
+    void writeFile(const std::string & fileName, const std::string & myFieldVal)
+    {
+        std::ofstream of;
+        of.open(fileName.c_str());
+        of << "myField \"" << myFieldVal << "\"\n";
+        of.close();
+    }
+}
+
+TEST("requireThatFileSpecGivesCorrectKey") {
+    std::string str("/home/my/config.cfg");
+    FileSpec spec(str);
+    bool thrown = false;
+    try {
+        FileSpec s1("fb");
+        FileSpec s2("fb.cfh");
+        FileSpec s3("fb.dch");
+        FileSpec s4("fbcfg");
+        FileSpec s5(".cfg");
+    } catch (const InvalidConfigSourceException & e) {
+        thrown = true;
+    }
+    ASSERT_TRUE(thrown);
+
+    thrown = false;
+    try {
+        FileSpec s1("fb.cfg");
+        FileSpec s2("a.cfg");
+        FileSpec s3("fljdlfjsalf.cfg");
+    } catch (const InvalidConfigSourceException & e) {
+        thrown = true;
+    }
+    ASSERT_FALSE(thrown);
+}
+
+TEST("requireThatFileSpecGivesCorrectSource") {
+    writeFile("my.cfg", "foobar");
+    FileSpec spec("my.cfg");
+
+    SourceFactory::UP factory(spec.createSourceFactory(TimingValues()));
+    ASSERT_TRUE(factory.get() != NULL);
+    IConfigHolder::SP holder(new ConfigHolder());
+    Source::UP src = factory->createSource(holder, ConfigKey("my", "my", "bar", "foo"));
+    ASSERT_TRUE(src.get() != NULL);
+
+    src->getConfig();
+    ASSERT_TRUE(holder->poll());
+    ConfigUpdate::UP update(holder->provide());
+    ASSERT_TRUE(update.get() != NULL);
+    const ConfigValue & value(update->getValue());
+    ASSERT_EQUAL(1u, value.numLines());
+    ASSERT_EQUAL("myField \"foobar\"", value.getLine(0));
+}
+
+TEST("requireThatFileSubscriptionReturnsCorrectConfig") {
+    writeFile("my.cfg", "foobar");
+    ConfigSubscriber s(FileSpec("my.cfg"));
+    std::unique_ptr<ConfigHandle<MyConfig> > handle = s.subscribe<MyConfig>("my");
+    s.nextConfig(0);
+    std::unique_ptr<MyConfig> cfg = handle->getConfig();
+    ASSERT_TRUE(cfg.get() != NULL);
+    ASSERT_EQUAL("foobar", cfg->myField);
+    ASSERT_EQUAL("my", cfg->defName());
+    ASSERT_FALSE(s.nextConfig(100));
+}
+
+TEST("requireThatReconfigIsCalledWhenConfigChanges") {
+    writeFile("my.cfg", "foo");
+    {
+        IConfigContext::SP context(new ConfigContext(FileSpec("my.cfg")));
+        ConfigSubscriber s(context);
+        std::unique_ptr<ConfigHandle<MyConfig> > handle = s.subscribe<MyConfig>("");
+        s.nextConfig(0);
+        std::unique_ptr<MyConfig> cfg = handle->getConfig();
+        ASSERT_TRUE(cfg.get() != NULL);
+        ASSERT_EQUAL("foo", cfg->myField);
+        ASSERT_EQUAL("my", cfg->defName());
+        ASSERT_FALSE(s.nextConfig(3000));
+        writeFile("my.cfg", "bar");
+        context->reload();
+        bool correctValue = false;
+        FastOS_Time timer;
+        timer.SetNow();
+        while (!correctValue && timer.MilliSecsToNow() < 20000.0) {
+            LOG(info, "Testing value...");
+            if (s.nextConfig(1000)) {
+                break;
+            }
+        }
+        cfg = handle->getConfig();
+        ASSERT_TRUE(cfg.get() != NULL);
+        ASSERT_EQUAL("bar", cfg->myField);
+        ASSERT_EQUAL("my", cfg->defName());
+        ASSERT_FALSE(s.nextConfig(1000));
+    }
+}
+
+TEST("requireThatMultipleSubscribersCanSubscribeToSameFile") {
+    writeFile("my.cfg", "foobar");
+    FileSpec spec("my.cfg");
+    {
+        ConfigSubscriber s1(spec);
+        std::unique_ptr<ConfigHandle<MyConfig> > h1 = s1.subscribe<MyConfig>("");
+        ASSERT_TRUE(s1.nextConfig(0));
+        ConfigSubscriber s2(spec);
+        std::unique_ptr<ConfigHandle<MyConfig> > h2 = s2.subscribe<MyConfig>("");
+        ASSERT_TRUE(s2.nextConfig(0));
+    }
+}
+
+TEST("requireThatCanSubscribeToDirectory") {
+    DirSpec spec("cfgdir");
+    ConfigSubscriber s(spec);
+    ConfigHandle<FooConfig>::UP fooHandle = s.subscribe<FooConfig>("");
+    ConfigHandle<BarConfig>::UP barHandle = s.subscribe<BarConfig>("");
+    ASSERT_TRUE(s.nextConfig(0));
+    ASSERT_TRUE(fooHandle->isChanged());
+    ASSERT_TRUE(barHandle->isChanged());
+    std::unique_ptr<FooConfig> fooCfg = fooHandle->getConfig();
+    std::unique_ptr<BarConfig> barCfg = barHandle->getConfig();
+    ASSERT_TRUE(fooCfg.get() != NULL);
+    ASSERT_TRUE(barCfg.get() != NULL);
+    ASSERT_EQUAL("foofoo", fooCfg->fooValue);
+    ASSERT_EQUAL("barbar", barCfg->barValue);
+}
+
+TEST("requireThatCanSubscribeToDirectoryWithEmptyCfgFile") {
+    DirSpec spec("cfgemptyfile");
+    ConfigSubscriber s(spec);
+    ConfigHandle<FoodefaultConfig>::UP fooHandle = s.subscribe<FoodefaultConfig>("");
+    ConfigHandle<BarConfig>::UP barHandle = s.subscribe<BarConfig>("");
+    ASSERT_TRUE(s.nextConfig(0));
+    ASSERT_TRUE(fooHandle->isChanged());
+    ASSERT_TRUE(barHandle->isChanged());
+    std::unique_ptr<FoodefaultConfig> fooCfg = fooHandle->getConfig();
+    std::unique_ptr<BarConfig> barCfg = barHandle->getConfig();
+    ASSERT_TRUE(fooCfg.get() != NULL);
+    ASSERT_TRUE(barCfg.get() != NULL);
+    ASSERT_EQUAL("per", fooCfg->fooValue);
+    ASSERT_EQUAL("barbar", barCfg->barValue);
+}
+
+TEST("requireThatCanSubscribeToDirectoryWithNonExistingCfgFile") {
+    DirSpec spec("cfgnonexistingfile");
+    ConfigSubscriber s(spec);
+    ConfigHandle<FoodefaultConfig>::UP fooHandle = s.subscribe<FoodefaultConfig>("");
+    ConfigHandle<BarConfig>::UP barHandle = s.subscribe<BarConfig>("");
+    ASSERT_TRUE(s.nextConfig(0));
+    ASSERT_TRUE(fooHandle->isChanged());
+    ASSERT_TRUE(barHandle->isChanged());
+    std::unique_ptr<FoodefaultConfig> fooCfg = fooHandle->getConfig();
+    std::unique_ptr<BarConfig> barCfg = barHandle->getConfig();
+    ASSERT_TRUE(fooCfg.get() != NULL);
+    ASSERT_TRUE(barCfg.get() != NULL);
+    ASSERT_EQUAL("per", fooCfg->fooValue);
+    ASSERT_EQUAL("barbar", barCfg->barValue);
+}
+
+TEST_F("requireThatDirSpecDoesNotMixNames", DirSpec("cfgdir2")) {
+    ConfigSubscriber s(f);
+    ConfigHandle<BarConfig>::UP barHandle = s.subscribe<BarConfig>("");
+    ConfigHandle<FoobarConfig>::UP foobarHandle = s.subscribe<FoobarConfig>("");
+    s.nextConfig(0);
+    std::unique_ptr<BarConfig> bar = barHandle->getConfig();
+    std::unique_ptr<FoobarConfig> foobar = foobarHandle->getConfig();
+    ASSERT_TRUE(bar.get() != NULL);
+    ASSERT_TRUE(foobar.get() != NULL);
+    ASSERT_EQUAL("barbar", bar->barValue);
+    ASSERT_EQUAL("foobarlol", foobar->fooBarValue);
+}
+
+TEST_F("require that can subscribe multiple config ids of same config", DirSpec("cfgdir3")) {
+    ConfigSubscriber s(f1);
+    ConfigHandle<BarConfig>::UP fooHandle = s.subscribe<BarConfig>("foo");
+    ConfigHandle<BarConfig>::UP barHandle = s.subscribe<BarConfig>("bar");
+    s.nextConfig(0);
+    std::unique_ptr<BarConfig> bar1 = fooHandle->getConfig();
+    std::unique_ptr<BarConfig> bar2 = barHandle->getConfig();
+    ASSERT_TRUE(bar1.get() != NULL);
+    ASSERT_TRUE(bar2.get() != NULL);
+    ASSERT_EQUAL("barbar", bar1->barValue);
+    ASSERT_EQUAL("foobarlol", bar2->barValue);
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/file_subscription/my.cfg b/config/src/tests/file_subscription/my.cfg
new file mode 100644
index 00000000000..6172609bdff
--- /dev/null
+++ b/config/src/tests/file_subscription/my.cfg
@@ -0,0 +1 @@
+myField "foobar"
diff --git a/config/src/tests/file_subscription/test1.cfg b/config/src/tests/file_subscription/test1.cfg
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/tests/file_subscription/test1.cfg
diff --git a/config/src/tests/frt/.gitignore b/config/src/tests/frt/.gitignore
new file mode 100644
index 00000000000..1a2e9c8eb78
--- /dev/null
+++ b/config/src/tests/frt/.gitignore
@@ -0,0 +1,5 @@
+/config-my.cpp
+/config-my.h
+/config-bar.cpp
+/config-bar.h
+config_frt_test_app
diff --git a/config/src/tests/frt/CMakeLists.txt b/config/src/tests/frt/CMakeLists.txt
new file mode 100644
index 00000000000..96f0fbb0076
--- /dev/null
+++ b/config/src/tests/frt/CMakeLists.txt
@@ -0,0 +1,10 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_frt_test_app
+    SOURCES
+    frt.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_frt_test_app COMMAND config_frt_test_app)
+vespa_generate_config(config_frt_test_app ../../test/resources/configdefinitions/my.def)
+vespa_generate_config(config_frt_test_app ../../test/resources/configdefinitions/bar.def)
diff --git a/config/src/tests/frt/frt.cpp b/config/src/tests/frt/frt.cpp
new file mode 100644
index 00000000000..c8d367d1558
--- /dev/null
+++ b/config/src/tests/frt/frt.cpp
@@ -0,0 +1,590 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP("frt");
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/common/iconfigholder.h>
+#include <vespa/config/common/trace.h>
+#include <vespa/config/common/configdefinition.h>
+#include <vespa/config/frt/connection.h>
+#include <vespa/config/frt/frtsource.h>
+#include <vespa/config/frt/frtconfigresponse.h>
+#include <vespa/config/frt/frtconfigrequest.h>
+#include <vespa/config/frt/frtconfigrequestv2.h>
+#include <vespa/config/frt/frtconfigresponsev2.h>
+#include <vespa/config/frt/frtconfigrequestv3.h>
+#include <vespa/config/frt/frtconfigresponsev3.h>
+#include <vespa/vespalib/data/slime/slime.h>
+#include <vespa/vespalib/data/slime/json_format.h>
+#include <vespa/fnet/fnet.h>
+#include <vespa/fnet/frt/frt.h>
+#include <vespa/fnet/frt/error.h>
+#include <vespa/config/frt/protocol.h>
+#include <lz4.h>
+#include "config-my.h"
+#include "config-bar.h"
+
+
+using namespace config;
+using namespace vespalib;
+using namespace vespalib::slime;
+using namespace config::protocol;
+using namespace config::protocol::v2;
+using namespace config::protocol::v3;
+
+namespace {
+
+    struct UpdateFixture : public IConfigHolder {
+        ConfigUpdate::UP update;
+        bool notified;
+
+        UpdateFixture()
+            : update(),
+              notified(false)
+        { }
+        ConfigUpdate::UP provide() { return ConfigUpdate::UP(); }
+        void handle(ConfigUpdate::UP u) { update = std::move(u); }
+        bool wait(int timeoutInMillis) { (void) timeoutInMillis; return notified; }
+        bool poll() { return notified; }
+        void interrupt() { }
+
+        bool waitUntilResponse(int timeoutInMillis)
+        {
+            FastOS_Time timer;
+            timer.SetNow();
+            while (timer.MilliSecsToNow() < timeoutInMillis) {
+                if (notified)
+                    break;
+                FastOS_Thread::Sleep(100);
+            }
+            return notified;
+        }
+    };
+
+    struct RPCFixture
+    {
+        std::vector<FRT_RPCRequest *> requests;
+        FRT_RPCRequest * createEmptyRequest() {
+            FRT_RPCRequest * req = new FRT_RPCRequest();
+            req->SetError(FRTE_NO_ERROR);
+            requests.push_back(req);
+            return req;
+        }
+        FRT_RPCRequest * createErrorRequest() {
+            FRT_RPCRequest * req = new FRT_RPCRequest();
+            req->SetError(FRTE_RPC_ABORT);
+            requests.push_back(req);
+            return req;
+        }
+        FRT_RPCRequest * createOKResponse(const vespalib::string & defName="",
+                                          const vespalib::string & defMd5="",
+                                          const vespalib::string & configId="",
+                                          const vespalib::string & configMd5="",
+                                          int changed=0,
+                                          long generation=0,
+                                          const std::vector<vespalib::string> & payload = std::vector<vespalib::string>(),
+                                          const vespalib::string & ns = "")
+        {
+            FRT_RPCRequest * req = new FRT_RPCRequest();
+            FRT_Values & ret = *req->GetReturn();
+
+            ret.AddString(defName.c_str());
+            ret.AddString("");
+            ret.AddString(defMd5.c_str());
+            ret.AddString(configId.c_str());
+            ret.AddString(configMd5.c_str());
+            ret.AddInt32(changed);
+            ret.AddInt64(generation);
+            FRT_StringValue * payload_arr = ret.AddStringArray(payload.size());
+            for (uint32_t i = 0; i < payload.size(); i++) {
+                ret.SetString(&payload_arr[i], payload[i].c_str());
+            }
+            if (!ns.empty())
+                ret.AddString(ns.c_str());
+            req->SetError(FRTE_NO_ERROR);
+            requests.push_back(req);
+            return req;
+        }
+
+        ~RPCFixture() {
+            for (size_t i = 0; i < requests.size(); i++) {
+                requests[i]->SubRef();
+            }
+        }
+    };
+
+
+    struct MyAbortHandler : public FRT_IAbortHandler
+    {
+        bool aborted;
+        MyAbortHandler() : aborted(false) { }
+        bool HandleAbort() { aborted = true; return true; }
+    };
+
+    struct ConnectionMock : public Connection {
+        int errorCode;
+        int timeout;
+        FRT_RPCRequest * ans;
+        FRT_Supervisor supervisor;
+        FNET_Scheduler scheduler;
+        vespalib::string address;
+        ConnectionMock(FRT_RPCRequest * answer = NULL)
+            : errorCode(0),
+              timeout(0),
+              ans(answer),
+              supervisor(),
+              address()
+        { }
+        FRT_RPCRequest * allocRPCRequest() { return supervisor.AllocRPCRequest(); }
+        void setError(int ec) { errorCode = ec; }
+        void invoke(FRT_RPCRequest * req, double t, FRT_IRequestWait * waiter)
+        {
+            timeout = static_cast<int>(t);
+            if (ans != NULL)
+                waiter->RequestDone(ans);
+            else
+                waiter->RequestDone(req);
+        }
+        const vespalib::string & getAddress() const { return address; }
+        void setTransientDelay(int64_t delay) { (void) delay; }
+    };
+
+    struct FactoryMock : public ConnectionFactory {
+        ConnectionMock * current;
+        FactoryMock(ConnectionMock * c) : current(c) { }
+        Connection * getCurrent() {
+            return current;
+        }
+        FNET_Scheduler * getScheduler() { return &current->scheduler; }
+        void syncTransport() { }
+    };
+
+
+    struct AgentResultFixture
+    {
+        bool notified;
+        uint64_t waitTime;
+        uint64_t timeout;
+        ConfigState state;
+        AgentResultFixture(uint64_t w, uint64_t t)
+            : notified(false),
+              waitTime(w),
+              timeout(t),
+              state()
+        { }
+    };
+
+    struct AgentFixture : public ConfigAgent
+    {
+        AgentResultFixture * result;
+
+        AgentFixture(AgentResultFixture * r)
+            : result(r)
+        {
+        }
+
+        const ConfigState & getConfigState() const { return result->state; }
+        uint64_t getWaitTime () const { return result->waitTime; }
+        uint64_t getTimeout() const { return result->timeout; }
+        void handleResponse(const ConfigRequest & request, ConfigResponse::UP response)
+        {
+            (void) request;
+            (void) response;
+            result->notified = true;
+        }
+        void handleRequest(ConfigRequest::UP request)
+        {
+            (void) request;
+        }
+        bool abort() { return true; }
+    };
+
+    struct SourceFixture {
+        RPCFixture rpc;
+        ConnectionMock conn;
+        ConfigKey key;
+        SourceFixture()
+            : rpc(),
+              conn(rpc.createOKResponse("foo", "baz", "4", "boo")),
+              key("foo", "bar", "4", "boo")
+        { }
+
+    };
+
+    struct FRTFixture
+    {
+        AgentResultFixture result;
+        FRTConfigRequestFactory requestFactory;
+        FRTSource src;
+
+        FRTFixture(SourceFixture & f1)
+            : result(2000, 10000),
+              requestFactory(1, 3, VespaVersion::fromString("1.2.3"), CompressionType::UNCOMPRESSED),
+              src(ConnectionFactory::SP(new FactoryMock(&f1.conn)),
+                  requestFactory,
+                  ConfigAgent::UP(new AgentFixture(&result)),
+                  f1.key)
+        { }
+    };
+}
+
+
+TEST_F("require that empty config response does not validate", RPCFixture()) {
+    FRTConfigResponseV1 fail1(f1.createEmptyRequest());
+    ASSERT_FALSE(fail1.validateResponse());
+    ASSERT_FALSE(fail1.hasValidResponse());
+    ASSERT_TRUE(fail1.isError());
+}
+
+TEST_F("require that response containing errors does not validate", RPCFixture()) {
+    FRTConfigResponseV1 fail1(f1.createErrorRequest());
+    ASSERT_FALSE(fail1.validateResponse());
+    ASSERT_FALSE(fail1.hasValidResponse());
+    ASSERT_TRUE(fail1.isError());
+    ASSERT_TRUE(fail1.errorCode() != 0);
+}
+
+TEST_F("require that valid response validates", RPCFixture()) {
+    std::vector<vespalib::string> vec;
+    vec.push_back("bar \"foo\"");
+    FRTConfigResponseV1 ok(f1.createOKResponse("foo", "baz", "bim", "boo", 12, 15, vec, "mn"));
+    ASSERT_TRUE(ok.validateResponse());
+    ASSERT_TRUE(ok.hasValidResponse());
+}
+
+TEST_F("require that response contains all values", RPCFixture()) {
+    FRTConfigResponseV1 ok(f1.createOKResponse("foo", "baz", "bim", "boo", 12, 15));
+    ASSERT_FALSE(ok.validateResponse());
+    ASSERT_FALSE(ok.hasValidResponse());
+}
+
+TEST_F("require that valid response returns values after fill", RPCFixture()) {
+    std::vector<vespalib::string> vec;
+    vec.push_back("bar \"foo\"");
+    FRTConfigResponseV1 ok(f1.createOKResponse("foo", "baz", "bim", "boo", 12, 15, vec, "mn"));
+    ASSERT_TRUE(ok.validateResponse());
+    ASSERT_TRUE(ok.hasValidResponse());
+
+    // Should not be valid
+    ASSERT_TRUE(ConfigKey() == ok.getKey());
+    ASSERT_TRUE(ConfigValue() == ok.getValue());
+
+    ok.fill();
+    ConfigKey key(ok.getKey());
+    ASSERT_EQUAL("foo", key.getDefName());
+    ASSERT_EQUAL("baz", key.getDefMd5());
+    ASSERT_EQUAL("bim", key.getConfigId());
+    ASSERT_EQUAL("mn", key.getDefNamespace());
+
+    ConfigValue value(ok.getValue());
+    ASSERT_TRUE(vec == value.getLines());
+}
+
+TEST("require that request parameters are correctly initialized") {
+    ConnectionMock conn;
+    std::vector<vespalib::string> schema;
+    schema.push_back("foo");
+    schema.push_back("bar");
+    ConfigKey key("foo", "bar", "bim", "boo", schema);
+    FRTConfigRequestV1 frtReq(key, &conn, "mymd5", 1337, 8);
+
+    FRT_RPCRequest * req = frtReq.getRequest();
+    FRT_Values & params(*req->GetParams());
+    ASSERT_EQUAL("bar", std::string(params[0]._string._str));
+    ASSERT_EQUAL("", std::string(params[1]._string._str));
+    ASSERT_EQUAL("boo", std::string(params[2]._string._str));
+    ASSERT_EQUAL("foo", std::string(params[3]._string._str));
+    ASSERT_EQUAL("mymd5", std::string(params[4]._string._str));
+    ASSERT_EQUAL(1337u, params[5]._intval64);
+    ASSERT_EQUAL(8u, params[6]._intval64);
+    ASSERT_EQUAL("bim", std::string(params[7]._string._str));
+    ASSERT_EQUAL(2u, params[8]._string_array._len);
+    ASSERT_EQUAL("foo", std::string(params[8]._string_array._pt[0]._str));
+    ASSERT_EQUAL("bar", std::string(params[8]._string_array._pt[1]._str));
+    ASSERT_EQUAL(1u, params[9]._intval32);
+}
+
+TEST("require that request is aborted") {
+    MyAbortHandler handler;
+    ConnectionMock conn;
+    ConfigKey key("foo", "bar", "bim", "boo");
+    FRTConfigRequestV1 frtReq(key, &conn, "mymd5", 1337, 8);
+    frtReq.getRequest()->SetAbortHandler(&handler);
+    ASSERT_FALSE(frtReq.isAborted());
+    ASSERT_TRUE(frtReq.abort());
+}
+
+TEST_FF("require that request is invoked", SourceFixture(),
+                                           FRTFixture(f1))
+{
+    f2.result.state = ConfigState("foo", 3);
+    f2.src.getConfig();
+    ASSERT_TRUE(f2.src.getCurrentRequest().verifyKey(f1.key));
+    ASSERT_FALSE(f2.src.getCurrentRequest().verifyKey(ConfigKey("foo", "bal", "bim", "boo", std::vector<vespalib::string>())));
+    ASSERT_FALSE(f2.src.getCurrentRequest().verifyState(ConfigState("foo", 0)));
+    ASSERT_FALSE(f2.src.getCurrentRequest().verifyState(ConfigState("foo", 1)));
+    ASSERT_FALSE(f2.src.getCurrentRequest().verifyState(ConfigState("bar", 1)));
+    ASSERT_TRUE(f2.src.getCurrentRequest().verifyState(ConfigState("foo", 3)));
+    ASSERT_TRUE(f2.result.notified);
+    f2.src.close();
+}
+
+TEST_FF("require that request is config task is scheduled", SourceFixture(),
+                                                            FRTFixture(f1))
+{
+    f2.src.getConfig();
+    ASSERT_TRUE(f2.result.notified);
+    f2.result.notified = false;
+    FastOS_Time timer;
+    timer.SetNow();
+    while (timer.MilliSecsToNow() < 10000) {
+        f1.conn.scheduler.CheckTasks();
+        if (f2.result.notified)
+            break;
+        FastOS_Thread::Sleep(500);
+    }
+    ASSERT_TRUE(f2.result.notified);
+    f2.src.close();
+}
+
+TEST("require that v2 request is correctly initialized") {
+    ConnectionMock conn;
+    ConfigKey key = ConfigKey::create<MyConfig>("foobi");
+    vespalib::string md5 = "mymd5";
+    int64_t currentGeneration = 3;
+    int64_t wantedGeneration = 4;
+    vespalib::string hostName = "myhost";
+    int64_t timeout = 3000;
+    Trace traceIn(3);
+    traceIn.trace(2, "Hei");
+    FRTConfigRequestV2 v2req(&conn, key, md5, currentGeneration, wantedGeneration, hostName, timeout, traceIn);
+    ConfigDefinition origDef(MyConfig::CONFIG_DEF_SCHEMA);
+
+    FRT_RPCRequest * req = v2req.getRequest();
+    ASSERT_TRUE(req != NULL);
+    FRT_Values & params(*req->GetParams());
+    std::string json(params[0]._string._str);
+    Slime slime;
+    JsonFormat::decode(Memory(json), slime);
+    Inspector & root(slime.get());
+    EXPECT_EQUAL(2, root[REQUEST_VERSION].asLong());
+    EXPECT_EQUAL(key.getDefName(), root[REQUEST_DEF_NAME].asString().make_string());
+    EXPECT_EQUAL(key.getDefNamespace(), root[REQUEST_DEF_NAMESPACE].asString().make_string());
+    EXPECT_EQUAL(key.getDefMd5(), root[REQUEST_DEF_MD5].asString().make_string());
+    EXPECT_EQUAL(key.getConfigId(), root[REQUEST_CLIENT_CONFIGID].asString().make_string());
+    EXPECT_EQUAL(hostName, root[REQUEST_CLIENT_HOSTNAME].asString().make_string());
+    EXPECT_EQUAL(currentGeneration, root[REQUEST_CURRENT_GENERATION].asLong());
+    EXPECT_EQUAL(wantedGeneration, root[REQUEST_WANTED_GENERATION].asLong());
+    EXPECT_EQUAL(md5, root[REQUEST_CONFIG_MD5].asString().make_string());
+    EXPECT_EQUAL(timeout, root[REQUEST_TIMEOUT].asLong());
+    Trace trace;
+    trace.deserialize(root[REQUEST_TRACE]);
+    EXPECT_TRUE(trace.shouldTrace(2));
+    EXPECT_TRUE(trace.shouldTrace(3));
+    EXPECT_FALSE(trace.shouldTrace(4));
+    EXPECT_EQUAL(timeout, root[REQUEST_TIMEOUT].asLong());
+    ConfigDefinition def;
+    def.deserialize(root[REQUEST_DEF_CONTENT]);
+    EXPECT_EQUAL(origDef.asString(), def.asString());
+    ConfigResponse::UP response(v2req.createResponse(req));
+    req->GetReturn()->AddString("foobar");
+    EXPECT_TRUE(response->validateResponse());
+}
+
+TEST("require that v2 reponse is correctly initialized") {
+    ConnectionMock conn;
+    Slime slime;
+    ConfigKey key = ConfigKey::create<MyConfig>("foobi");
+    vespalib::string md5 = "mymd5";
+    int64_t generation = 3;
+    vespalib::string hostname = "myhhost";
+    Trace traceIn(3);
+    traceIn.trace(2, "Hei!");
+    Cursor & root(slime.setObject());
+    root.setLong(RESPONSE_VERSION, 2ul);
+    root.setString(RESPONSE_DEF_NAME, Memory(key.getDefName()));
+    root.setString(RESPONSE_DEF_NAMESPACE, Memory(key.getDefNamespace()));
+    root.setString(RESPONSE_DEF_MD5, Memory(key.getDefMd5()));
+    root.setString(RESPONSE_CONFIGID, Memory(key.getConfigId()));
+    root.setString(RESPONSE_CLIENT_HOSTNAME, Memory(hostname));
+    root.setString(RESPONSE_CONFIG_MD5, Memory(md5));
+    root.setLong(RESPONSE_CONFIG_GENERATION, generation);
+    traceIn.serialize(root.setObject(RESPONSE_TRACE));
+    Cursor & payload(root.setObject(RESPONSE_PAYLOAD));
+    payload.setString("myField", "foobiar");
+    SimpleBuffer buf;
+    JsonFormat::encode(slime, buf, true);
+    FRT_RPCRequest * req = conn.allocRPCRequest();
+    req->GetReturn()->AddString(buf.get().make_string().c_str());
+    FRTConfigResponseV2 response(req);
+    ASSERT_TRUE(response.validateResponse());
+    response.fill();
+    Trace trace(response.getTrace());
+    EXPECT_TRUE(trace.shouldTrace(3));
+    EXPECT_FALSE(trace.shouldTrace(4));
+    ConfigKey responseKey(response.getKey());
+    EXPECT_EQUAL(key.getDefName(), responseKey.getDefName());
+    EXPECT_EQUAL(key.getDefNamespace(), responseKey.getDefNamespace());
+    EXPECT_EQUAL(key.getDefMd5(), responseKey.getDefMd5());
+    EXPECT_EQUAL(key.getConfigId(), responseKey.getConfigId());
+    EXPECT_EQUAL(hostname, response.getHostName());
+    ConfigState state(response.getConfigState());
+    EXPECT_EQUAL(md5, state.md5);
+    EXPECT_EQUAL(generation, state.generation);
+    ConfigValue value(response.getValue());
+    MyConfig::UP config(value.newInstance<MyConfig>());
+    EXPECT_EQUAL("foobiar", config->myField);
+    req->SubRef();
+}
+
+TEST("require that v3 request is correctly initialized") {
+    ConnectionMock conn;
+    ConfigKey key = ConfigKey::create<MyConfig>("foobi");
+    vespalib::string md5 = "mymd5";
+    int64_t currentGeneration = 3;
+    int64_t wantedGeneration = 4;
+    vespalib::string hostName = "myhost";
+    int64_t timeout = 3000;
+    Trace traceIn(3);
+    traceIn.trace(2, "Hei");
+    FRTConfigRequestV3 v3req(&conn, key, md5, currentGeneration, wantedGeneration, hostName, timeout, traceIn, VespaVersion::fromString("1.2.3"), CompressionType::LZ4);
+    ConfigDefinition origDef(MyConfig::CONFIG_DEF_SCHEMA);
+
+    FRT_RPCRequest * req = v3req.getRequest();
+    ASSERT_TRUE(req != NULL);
+    FRT_Values & params(*req->GetParams());
+    std::string json(params[0]._string._str);
+    Slime slime;
+    JsonFormat::decode(Memory(json), slime);
+    Inspector & root(slime.get());
+    EXPECT_EQUAL(3, root[REQUEST_VERSION].asLong());
+    EXPECT_EQUAL(key.getDefName(), root[REQUEST_DEF_NAME].asString().make_string());
+    EXPECT_EQUAL(key.getDefNamespace(), root[REQUEST_DEF_NAMESPACE].asString().make_string());
+    EXPECT_EQUAL(key.getDefMd5(), root[REQUEST_DEF_MD5].asString().make_string());
+    EXPECT_EQUAL(key.getConfigId(), root[REQUEST_CLIENT_CONFIGID].asString().make_string());
+    EXPECT_EQUAL(hostName, root[REQUEST_CLIENT_HOSTNAME].asString().make_string());
+    EXPECT_EQUAL(currentGeneration, root[REQUEST_CURRENT_GENERATION].asLong());
+    EXPECT_EQUAL(wantedGeneration, root[REQUEST_WANTED_GENERATION].asLong());
+    EXPECT_EQUAL(md5, root[REQUEST_CONFIG_MD5].asString().make_string());
+    EXPECT_EQUAL(timeout, root[REQUEST_TIMEOUT].asLong());
+    EXPECT_EQUAL("LZ4", root[REQUEST_COMPRESSION_TYPE].asString().make_string());
+    EXPECT_EQUAL(root[REQUEST_VESPA_VERSION].asString().make_string(), "1.2.3");
+    Trace trace;
+    trace.deserialize(root[REQUEST_TRACE]);
+    EXPECT_TRUE(trace.shouldTrace(2));
+    EXPECT_TRUE(trace.shouldTrace(3));
+    EXPECT_FALSE(trace.shouldTrace(4));
+    EXPECT_EQUAL(timeout, root[REQUEST_TIMEOUT].asLong());
+    ConfigDefinition def;
+    def.deserialize(root[REQUEST_DEF_CONTENT]);
+    EXPECT_EQUAL(origDef.asString(), def.asString());
+    ConfigResponse::UP response(v3req.createResponse(req));
+    req->GetReturn()->AddString("foobar");
+    req->GetReturn()->AddData("foo", 3);
+    EXPECT_TRUE(response->validateResponse());
+}
+
+struct V3RequestFixture {
+    ConnectionMock conn;
+    Slime slime;
+    Cursor & root;
+    FRT_RPCRequest * req;
+    ConfigKey key;
+    vespalib::string md5;
+    int64_t generation;
+    vespalib::string hostname;
+    Trace traceIn;
+
+    V3RequestFixture()
+        : conn(),
+          slime(),
+          root(slime.setObject()),
+          req(conn.allocRPCRequest()), 
+          key(ConfigKey::create<BarConfig>("foobi")),
+          md5("mymd5"),
+          generation(3),
+          hostname("myhhost"),
+          traceIn(3)
+    {
+        traceIn.trace(2, "Hei!");
+        root.setLong(RESPONSE_VERSION, 3ul);
+        root.setString(RESPONSE_DEF_NAME, Memory(key.getDefName()));
+        root.setString(RESPONSE_DEF_NAMESPACE, Memory(key.getDefNamespace()));
+        root.setString(RESPONSE_DEF_MD5, Memory(key.getDefMd5()));
+        root.setString(RESPONSE_CONFIGID, Memory(key.getConfigId()));
+        root.setString(RESPONSE_CLIENT_HOSTNAME, Memory(hostname));
+        root.setString(RESPONSE_CONFIG_MD5, Memory(md5));
+        root.setLong(RESPONSE_CONFIG_GENERATION, generation);
+        traceIn.serialize(root.setObject(RESPONSE_TRACE));
+    }
+
+    ~V3RequestFixture() {
+        req->SubRef();
+    }
+
+    void encodePayload(const char * payload, uint32_t payloadSize, uint32_t uncompressedSize, const CompressionType & compressionType) {
+        Cursor & compressionInfo(root.setObject(RESPONSE_COMPRESSION_INFO));
+        compressionInfo.setString("compressionType", Memory(compressionTypeToString(compressionType)));
+        compressionInfo.setLong("uncompressedSize", uncompressedSize);
+        SimpleBuffer buf;
+        JsonFormat::encode(slime, buf, true);
+        req->GetReturn()->AddString(buf.get().make_string().c_str());
+        req->GetReturn()->AddData(payload, payloadSize);
+    }
+
+    FRTConfigResponseV3 * createResponse() {
+        return new FRTConfigResponseV3(req);
+    }
+
+    void assertResponse(const FRTConfigResponseV3 & response, const char *expectedValue) {
+        Trace trace(response.getTrace());
+        EXPECT_TRUE(trace.shouldTrace(3));
+        EXPECT_FALSE(trace.shouldTrace(4));
+        ConfigKey responseKey(response.getKey());
+        EXPECT_EQUAL(key.getDefName(), responseKey.getDefName());
+        EXPECT_EQUAL(key.getDefNamespace(), responseKey.getDefNamespace());
+        EXPECT_EQUAL(key.getDefMd5(), responseKey.getDefMd5());
+        EXPECT_EQUAL(key.getConfigId(), responseKey.getConfigId());
+        EXPECT_EQUAL(hostname, response.getHostName());
+        ConfigState state(response.getConfigState());
+        EXPECT_EQUAL(md5, state.md5);
+        EXPECT_EQUAL(generation, state.generation);
+        ConfigValue value(response.getValue());
+        BarConfig::UP config(value.newInstance<BarConfig>());
+        EXPECT_EQUAL(expectedValue, config->barValue);
+    }
+};
+
+TEST_F("require that v3 uncompressed reponse is correctly initialized", V3RequestFixture()) {
+    const char *payload = "{\"barValue\":\"foobiar\"}";
+    f1.encodePayload(payload, strlen(payload), strlen(payload), CompressionType::UNCOMPRESSED);
+    std::unique_ptr<FRTConfigResponseV3> response(f1.createResponse());
+    ASSERT_TRUE(response->validateResponse());
+    response->fill();
+    f1.assertResponse(*response, "foobiar");
+}
+
+TEST_F("require that v3 compressed reponse is correctly initialized", V3RequestFixture()) {
+    const char *payload = "{\"barValue\":\"foobiar\"}";
+    int maxSize = LZ4_compressBound(strlen(payload));
+    char *output = (char *)malloc(maxSize);
+    int sz = LZ4_compress(payload, output, strlen(payload));
+
+    f1.encodePayload(output, sz, strlen(payload), CompressionType::LZ4);
+    std::unique_ptr<FRTConfigResponseV3> response(f1.createResponse());
+    ASSERT_TRUE(response->validateResponse());
+    response->fill();
+    f1.assertResponse(*response, "foobiar");
+    free(output);
+}
+
+TEST_F("require that empty v3 reponse is correctly initialized", V3RequestFixture()) {
+    const char *payload = "";
+    f1.encodePayload(payload, strlen(payload), strlen(payload), CompressionType::UNCOMPRESSED);
+    std::unique_ptr<FRTConfigResponseV3> response(f1.createResponse());
+    ASSERT_TRUE(response->validateResponse());
+    response->fill();
+    f1.assertResponse(*response, "defaultBar");
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/frtconnectionpool/.gitignore b/config/src/tests/frtconnectionpool/.gitignore
new file mode 100644
index 00000000000..8c5f46e1254
--- /dev/null
+++ b/config/src/tests/frtconnectionpool/.gitignore
@@ -0,0 +1,4 @@
+.depend
+Makefile
+frtconnectionpool_test
+config_frtconnectionpool_test_app
diff --git a/config/src/tests/frtconnectionpool/CMakeLists.txt b/config/src/tests/frtconnectionpool/CMakeLists.txt
new file mode 100644
index 00000000000..1979577f5fb
--- /dev/null
+++ b/config/src/tests/frtconnectionpool/CMakeLists.txt
@@ -0,0 +1,8 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_frtconnectionpool_test_app
+    SOURCES
+    frtconnectionpool.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_frtconnectionpool_test_app COMMAND config_frtconnectionpool_test_app)
diff --git a/config/src/tests/frtconnectionpool/DESC b/config/src/tests/frtconnectionpool/DESC
new file mode 100644
index 00000000000..141c067238f
--- /dev/null
+++ b/config/src/tests/frtconnectionpool/DESC
@@ -0,0 +1 @@
+frtconnectionpool test. Take a look at frtconnectionpool.cpp for details.
diff --git a/config/src/tests/frtconnectionpool/FILES b/config/src/tests/frtconnectionpool/FILES
new file mode 100644
index 00000000000..d0bcc084a30
--- /dev/null
+++ b/config/src/tests/frtconnectionpool/FILES
@@ -0,0 +1 @@
+frtconnectionpool.cpp
diff --git a/config/src/tests/frtconnectionpool/frtconnectionpool.cpp b/config/src/tests/frtconnectionpool/frtconnectionpool.cpp
new file mode 100644
index 00000000000..93163065eae
--- /dev/null
+++ b/config/src/tests/frtconnectionpool/frtconnectionpool.cpp
@@ -0,0 +1,247 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP("frtconnectionpool_test");
+#include <vespa/vespalib/testkit/testapp.h>
+#include <vespa/config/frt/frtconnectionpool.h>
+#include <vespa/fnet/frt/error.h>
+#include <sstream>
+#include <set>
+
+using namespace config;
+
+class Test : public vespalib::TestApp {
+private:
+    static ServerSpec::HostSpecList _sources;
+    void verifyAllSourcesInRotation(FRTConnectionPool& sourcePool);
+public:
+    int Main();
+    void testBasicRoundRobin();
+    void testBasicHashBasedSelection();
+    void testSetErrorRoundRobin();
+    void testSetErrorAllRoundRobin();
+    void testSetErrorHashBased();
+    void testSetErrorAllHashBased();
+    void testSuspensionTimeout();
+    void testManySources();
+};
+
+TEST_APPHOOK(Test);
+
+ServerSpec::HostSpecList Test::_sources;
+TimingValues timingValues;
+
+int Test::Main() {
+    TEST_INIT("frtconnectionpool_test");
+
+    _sources.push_back("host0");
+    _sources.push_back("host1");
+    _sources.push_back("host2");
+
+    testBasicRoundRobin();
+    TEST_FLUSH();
+
+    testBasicHashBasedSelection();
+    TEST_FLUSH();
+
+    testSetErrorRoundRobin();
+    TEST_FLUSH();
+
+    testSetErrorAllRoundRobin();
+    TEST_FLUSH();
+
+    testSetErrorHashBased();
+    TEST_FLUSH();
+
+    testSetErrorAllHashBased();
+    TEST_FLUSH();
+
+    testSuspensionTimeout();
+    TEST_FLUSH();
+
+    testManySources();
+    TEST_FLUSH();
+
+    TEST_DONE();
+    return 0;
+}
+
+void Test::verifyAllSourcesInRotation(FRTConnectionPool& sourcePool) {
+    std::set<std::string> completeSet(_sources.begin(), _sources.end());
+    std::set<std::string> foundSet;
+    for (int i = 0; i < (int)_sources.size(); i++) {
+        foundSet.insert(sourcePool.getNextRoundRobin()->getAddress());
+    }
+    EXPECT_EQUAL(true, completeSet == foundSet);
+}
+
+/**
+ * Tests that basic round robin selection through the list works.
+ */
+void Test::testBasicRoundRobin() {
+    const ServerSpec spec(_sources);
+    FRTConnectionPool sourcePool(spec, timingValues);
+    for (int i = 0; i < 9; i++) {
+        int j = i % _sources.size();
+        std::stringstream s;
+        s << "host" << j;
+        EXPECT_EQUAL(s.str(), sourcePool.getNextRoundRobin()->getAddress());
+    }
+}
+
+/**
+ * Tests that hash-based selection through the list works.
+ */
+void Test::testBasicHashBasedSelection() {
+    const ServerSpec spec(_sources);
+    FRTConnectionPool sourcePool(spec, timingValues);
+    sourcePool.setHostname("a.b.com");
+    for (int i = 0; i < 9; i++) {
+        EXPECT_EQUAL("host1", sourcePool.getNextHashBased()->getAddress());
+    }
+    sourcePool.setHostname("host98");
+    for (int i = 0; i < 9; i++) {
+        EXPECT_EQUAL("host0", sourcePool.getNextHashBased()->getAddress());
+    }
+
+    ServerSpec::HostSpecList hostnames;
+    hostnames.push_back("sutter-01.example.yahoo.com");
+    hostnames.push_back("stroustrup-02.example.yahoo.com");
+    hostnames.push_back("alexandrescu-03.example.yahoo.com");
+    const ServerSpec spec2(hostnames);
+    FRTConnectionPool sourcePool2(spec2, timingValues);
+    sourcePool2.setHostname("sutter-01.example.yahoo.com");
+    EXPECT_EQUAL("stroustrup-02.example.yahoo.com", sourcePool2.getNextHashBased()->getAddress());
+    sourcePool2.setHostname("stroustrup-02.example.yahoo.com");
+    EXPECT_EQUAL("sutter-01.example.yahoo.com", sourcePool2.getNextHashBased()->getAddress());
+    sourcePool2.setHostname("alexandrescu-03.example.yahoo.com");
+    EXPECT_EQUAL("alexandrescu-03.example.yahoo.com", sourcePool2.getNextHashBased()->getAddress());
+}
+
+/**
+ * Tests that a source is taken out of rotation when an error is reported,
+ * and that it is taken back in when a success is reported.
+ */
+void Test::testSetErrorRoundRobin() {
+    const ServerSpec spec(_sources);
+    FRTConnectionPool sourcePool(spec, timingValues);
+    FRTConnection* source = sourcePool.getNextRoundRobin();
+    source->setError(FRTE_RPC_CONNECTION);
+    for (int i = 0; i < 9; i++) {
+        EXPECT_NOT_EQUAL(source->getAddress(), sourcePool.getCurrent()->getAddress());
+    }
+    source->setSuccess();
+    verifyAllSourcesInRotation(sourcePool);
+}
+
+/**
+ * Tests that all sources are in rotation when all sources have errors set.
+ */
+void Test::testSetErrorAllRoundRobin() {
+    const ServerSpec spec(_sources);
+    FRTConnectionPool sourcePool(spec, timingValues);
+    for (int i = 0; i < (int)_sources.size(); i++) {
+        FRTConnection* source = sourcePool.getNextRoundRobin();
+        source->setError(FRTE_RPC_CONNECTION);
+    }
+    verifyAllSourcesInRotation(sourcePool);
+}
+
+/**
+ * Tests that a source is not used when an error is reported,
+ * and that the same source is used when a success is reported.
+ */
+void Test::testSetErrorHashBased() {
+    const ServerSpec spec(_sources);
+    FRTConnectionPool sourcePool(spec, timingValues);
+    FRTConnection* source = sourcePool.getNextHashBased();
+    source->setError(FRTE_RPC_CONNECTION);
+    for (int i = 0; i < (int)_sources.size(); i++) {
+        EXPECT_NOT_EQUAL(source->getAddress(), sourcePool.getNextHashBased()->getAddress());
+    }
+    source->setSuccess();
+    EXPECT_EQUAL(source->getAddress(), sourcePool.getNextHashBased()->getAddress());
+}
+
+/**
+ * Tests that the same source is used when all sources have errors set.
+ */
+void Test::testSetErrorAllHashBased() {
+    const ServerSpec spec(_sources);
+    FRTConnectionPool sourcePool(spec, timingValues);
+    FRTConnection* firstSource = sourcePool.getNextHashBased();
+    std::vector<FRTConnection*> readySources;
+    sourcePool.getReadySources(readySources);
+    for (int i = 0; i < (int)readySources.size(); i++) {
+        readySources[i]->setError(FRTE_RPC_CONNECTION);
+    }
+    std::vector<FRTConnection*> tmpSources;
+    EXPECT_EQUAL((int)sourcePool.getReadySources(tmpSources).size(), 0);
+    EXPECT_EQUAL((int)sourcePool.getSuspendedSources(tmpSources).size(), 3);
+
+    // should get the same source now, since all are suspended
+    EXPECT_EQUAL(firstSource->getAddress(), sourcePool.getNextHashBased()->getAddress());
+
+    // set all except firstSource to OK
+    for (int i = 0; i < (int)readySources.size(); i++) {
+        if (readySources[i]->getAddress() != firstSource->getAddress()) {
+            readySources[i]->setSuccess();
+        }
+    }
+
+    EXPECT_EQUAL((int)sourcePool.getReadySources(tmpSources).size(), 2);
+    EXPECT_EQUAL((int)sourcePool.getSuspendedSources(tmpSources).size(), 1);
+
+    // should not get the same source now, since original source is
+    // suspended, while the rest are OK
+    EXPECT_NOT_EQUAL(firstSource->getAddress(), sourcePool.getNextHashBased()->getAddress());
+}
+
+/**
+ * Tests that the source is put back into rotation when the suspension times out.
+ */
+void Test::testSuspensionTimeout() {
+    const ServerSpec spec(_sources);
+    FRTConnectionPool sourcePool(spec, timingValues);
+    Connection* source = sourcePool.getCurrent();
+    source->setTransientDelay(1000);
+    source->setError(FRTE_RPC_CONNECTION);
+    for (int i = 0; i < 9; i++) {
+        EXPECT_NOT_EQUAL(source->getAddress(), sourcePool.getCurrent()->getAddress());
+    }
+    sleep(2);
+    verifyAllSourcesInRotation(sourcePool);
+}
+
+/**
+ * Tests that when there are two sources and several clients
+ * the sources will be chosen with equal probability.
+ */
+void Test::testManySources() {
+    std::vector<std::string> hostnames;
+    for (int i = 0; i < 20; ++i) {
+        hostnames.push_back("host-" + std::to_string(i) + ".example.yahoo.com");
+    }
+
+    std::map<std::string, int> timesUsed;
+    ServerSpec::HostSpecList twoSources;
+
+    twoSources.push_back("host0");
+    twoSources.push_back("host1");
+
+    const ServerSpec spec(twoSources);
+    FRTConnectionPool sourcePool(spec, timingValues);
+
+    for (int i = 0; i < (int)hostnames.size(); i++) {
+        sourcePool.setHostname(hostnames[i]);
+        std::string address = sourcePool.getNextHashBased()->getAddress();
+        if (timesUsed.find(address) != timesUsed.end()) {
+            int times = timesUsed[address];
+            timesUsed[address] = times + 1;
+        } else {
+            timesUsed[address] = 1;
+        }
+    }
+    EXPECT_EQUAL(timesUsed["host0"], (int)hostnames.size() / 2);
+    EXPECT_EQUAL(timesUsed["host1"], (int)hostnames.size() / 2);
+}
diff --git a/config/src/tests/functiontest/.gitignore b/config/src/tests/functiontest/.gitignore
new file mode 100644
index 00000000000..44d74bb5ec7
--- /dev/null
+++ b/config/src/tests/functiontest/.gitignore
@@ -0,0 +1,6 @@
+.depend
+Makefile
+functiontesttest_test
+/config-function-test.cpp
+/config-function-test.h
+config_functiontest_test_app
diff --git a/config/src/tests/functiontest/CMakeLists.txt b/config/src/tests/functiontest/CMakeLists.txt
new file mode 100644
index 00000000000..d798ad53de4
--- /dev/null
+++ b/config/src/tests/functiontest/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_functiontest_test_app
+    SOURCES
+    functiontest.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_functiontest_test_app COMMAND config_functiontest_test_app)
+vespa_generate_config(config_functiontest_test_app ../../test/resources/configdefinitions/function-test.def)
diff --git a/config/src/tests/functiontest/defaultvalues.xml b/config/src/tests/functiontest/defaultvalues.xml
new file mode 100644
index 00000000000..80644c2fdb1
--- /dev/null
+++ b/config/src/tests/functiontest/defaultvalues.xml
@@ -0,0 +1,62 @@
+<?xml version="1.0" encoding="utf-8" ?>
+<!-- Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root. -->
+<config name="function-test">
+  <bool_val>false</bool_val>
+  <int_val>5</int_val>
+  <long_val>1234567890123</long_val>
+  <double_val>41.23</double_val>
+  <string_val>foo</string_val>
+  <enum_val>FOOBAR</enum_val>
+  <refval>:parent:</refval>
+  <fileVal>vespa.log</fileVal>
+
+  <boolarr index="0">false</boolarr>
+  <doublearr index="0">2344</doublearr>
+  <doublearr index="1">123</doublearr>
+  <stringarr index="0">bar</stringarr>
+  <enumarr index="0">VALUES</enumarr>
+
+  <basicStruct>
+    <bar>3</bar>
+    <intArr index="0">10</intArr>
+  </basicStruct>
+
+  <rootStruct>
+    <inner0>
+      <index>11</index>
+    </inner0>
+    <inner1>
+      <index>12</index>
+    </inner1>
+    <innerArr index="0">
+      <stringVal>deep</stringVal>
+    </innerArr>
+  </rootStruct>
+
+  <myarray index="0">
+    <stringval index="0">baah</stringval>
+    <stringval index="1">yikes</stringval>
+    <refval>:parent:</refval>
+    <fileVal>command.com</fileVal>
+    <anotherarray index="0">
+      <foo>7</foo>
+    </anotherarray>
+    <myStruct>
+      <a>1</a>
+    </myStruct>
+  </myarray>
+  <myarray index="1">
+    <refval>:parent:</refval>
+    <fileVal>display.sys</fileVal>
+    <anotherarray index="0">
+      <foo>1</foo>
+    </anotherarray>
+    <anotherarray index="1">
+      <foo>2</foo>
+    </anotherarray>
+    <myStruct>
+      <a>-1</a>
+    </myStruct>
+  </myarray>
+
+</config>
diff --git a/config/src/tests/functiontest/defaultvalues/function-test.cfg b/config/src/tests/functiontest/defaultvalues/function-test.cfg
new file mode 100644
index 00000000000..854d2a5a1cb
--- /dev/null
+++ b/config/src/tests/functiontest/defaultvalues/function-test.cfg
@@ -0,0 +1,46 @@
+bool_val false
+int_val 5
+long_val 1234567890123
+double_val 41.23
+string_val "foo"
+enum_val FOOBAR
+refval :parent:
+fileVal "vespa.log"
+boolarr[1]
+boolarr[0] false
+intarr[0]
+longarr[0]
+doublearr[2]
+doublearr[0] 2344
+doublearr[1] 123
+stringarr[1]
+stringarr[0] "bar"
+enumarr[1]
+enumarr[0] VALUES
+refarr[0]
+fileArr[0]
+
+basicStruct.bar 3
+basicStruct.intArr[1]
+basicStruct.intArr[0] 10
+rootStruct.inner0.index 11
+rootStruct.inner1.index 12
+rootStruct.innerArr[1]
+rootStruct.innerArr[0].stringVal "deep"
+
+myarray[2]
+myarray[0].stringval[2]
+myarray[0].stringval[0] "baah"
+myarray[0].stringval[1] "yikes"
+myarray[0].refval ":parent:"
+myarray[0].fileVal "command.com"
+myarray[0].anotherarray[1]
+myarray[0].anotherarray[0].foo 7
+myarray[0].myStruct.a 1
+myarray[1].stringval[0]
+myarray[1].refval ":parent:"
+myarray[1].fileVal "display.sys"
+myarray[1].anotherarray[2]
+myarray[1].anotherarray[0].foo 1
+myarray[1].anotherarray[1].foo 2
+myarray[1].myStruct.a -1
diff --git a/config/src/tests/functiontest/errorval_double/function-test.cfg b/config/src/tests/functiontest/errorval_double/function-test.cfg
new file mode 100644
index 00000000000..d6fff604406
--- /dev/null
+++ b/config/src/tests/functiontest/errorval_double/function-test.cfg
@@ -0,0 +1,67 @@
+bool_val false
+bool_with_def true
+int_val 5
+int_with_def -14
+long_val 12345678901
+long_with_def -9876543210
+double_val 41.23jf
+double_with_def -12
+string_val "foo"
+stringwithdef "bar"
+enum_val FOOBAR
+enumwithdef BAR2
+refval :parent:
+refwithdef ":parent:"
+fileVal "etc"
+boolarr[1]
+boolarr[0] false
+intarr[0]
+longarr[2]
+longarr[0] 9223372036854775807
+longarr[1] -9223372036854775808
+doublearr[2]
+doublearr[0] 2344
+doublearr[1] 123
+stringarr[1]
+stringarr[0] "bar"
+enumarr[1]
+enumarr[0] VALUES
+refarr[3]
+refarr[0] ":parent:"
+refarr[1] ":parent"
+refarr[2] "parent:"
+fileArr[1]
+fileArr[0] "bin"
+
+basicStruct.foo "basicFoo"
+basicStruct.bar 3
+basicStruct.intArr[1]
+basicStruct.intArr[0] 310
+rootStruct.inner0.index 11
+rootStruct.inner1.index 12
+rootStruct.innerArr[1]
+rootStruct.innerArr[0].boolVal true
+rootStruct.innerArr[0].stringVal "deep"
+
+myarray[2]
+myarray[0].intval -5
+myarray[0].stringval[2]
+myarray[0].stringval[0] "baah"
+myarray[0].stringval[1] "yikes"
+myarray[0].enumval INNER
+myarray[0].refval :parent:
+myarray[0].fileVal "file0"
+myarray[0].anotherarray[1]
+myarray[0].anotherarray[0].foo 7
+myarray[0].myStruct.a 1
+myarray[0].myStruct.b 2
+myarray[1].intval 5
+myarray[1].stringval[0]
+myarray[1].enumval INNER
+myarray[1].refval ":parent:"
+myarray[1].fileVal "file1"
+myarray[1].anotherarray[2]
+myarray[1].anotherarray[0].foo 1
+myarray[1].anotherarray[1].foo 2
+myarray[1].myStruct.a -1
+myarray[1].myStruct.b -2
diff --git a/config/src/tests/functiontest/errorval_int/function-test.cfg b/config/src/tests/functiontest/errorval_int/function-test.cfg
new file mode 100644
index 00000000000..7f3eba1ba55
--- /dev/null
+++ b/config/src/tests/functiontest/errorval_int/function-test.cfg
@@ -0,0 +1,67 @@
+bool_val false
+bool_with_def true
+int_val 5foo
+int_with_def -14
+long_val 12345678901
+long_with_def -9876543210
+double_val 41.23
+double_with_def -12
+string_val "foo"
+stringwithdef "bar"
+enum_val FOOBAR
+enumwithdef BAR2
+refval :parent:
+refwithdef ":parent:"
+fileVal "etc"
+boolarr[1]
+boolarr[0] false
+intarr[0]
+longarr[2]
+longarr[0] 9223372036854775807
+longarr[1] -9223372036854775808
+doublearr[2]
+doublearr[0] 2344
+doublearr[1] 123
+stringarr[1]
+stringarr[0] "bar"
+enumarr[1]
+enumarr[0] VALUES
+refarr[3]
+refarr[0] ":parent:"
+refarr[1] ":parent"
+refarr[2] "parent:"
+fileArr[1]
+fileArr[0] "bin"
+
+basicStruct.foo "basicFoo"
+basicStruct.bar 3
+basicStruct.intArr[1]
+basicStruct.intArr[0] 310
+rootStruct.inner0.index 11
+rootStruct.inner1.index 12
+rootStruct.innerArr[1]
+rootStruct.innerArr[0].boolVal true
+rootStruct.innerArr[0].stringVal "deep"
+
+myarray[2]
+myarray[0].intval -5
+myarray[0].stringval[2]
+myarray[0].stringval[0] "baah"
+myarray[0].stringval[1] "yikes"
+myarray[0].enumval INNER
+myarray[0].refval :parent:
+myarray[0].fileVal "file0"
+myarray[0].anotherarray[1]
+myarray[0].anotherarray[0].foo 7
+myarray[0].myStruct.a 1
+myarray[0].myStruct.b 2
+myarray[1].intval 5
+myarray[1].stringval[0]
+myarray[1].enumval INNER
+myarray[1].refval ":parent:"
+myarray[1].fileVal "file1"
+myarray[1].anotherarray[2]
+myarray[1].anotherarray[0].foo 1
+myarray[1].anotherarray[1].foo 2
+myarray[1].myStruct.a -1
+myarray[1].myStruct.b -2
diff --git a/config/src/tests/functiontest/errorval_long/function-test.cfg b/config/src/tests/functiontest/errorval_long/function-test.cfg
new file mode 100644
index 00000000000..ab14a1a9e5a
--- /dev/null
+++ b/config/src/tests/functiontest/errorval_long/function-test.cfg
@@ -0,0 +1,67 @@
+bool_val false
+bool_with_def true
+int_val 5
+int_with_def -14
+long_val 12345678901foo
+long_with_def -9876543210
+double_val 41.23
+double_with_def -12
+string_val "foo"
+stringwithdef "bar"
+enum_val FOOBAR
+enumwithdef BAR2
+refval :parent:
+refwithdef ":parent:"
+fileVal "etc"
+boolarr[1]
+boolarr[0] false
+intarr[0]
+longarr[2]
+longarr[0] 9223372036854775807
+longarr[1] -9223372036854775808
+doublearr[2]
+doublearr[0] 2344
+doublearr[1] 123
+stringarr[1]
+stringarr[0] "bar"
+enumarr[1]
+enumarr[0] VALUES
+refarr[3]
+refarr[0] ":parent:"
+refarr[1] ":parent"
+refarr[2] "parent:"
+fileArr[1]
+fileArr[0] "bin"
+
+basicStruct.foo "basicFoo"
+basicStruct.bar 3
+basicStruct.intArr[1]
+basicStruct.intArr[0] 310
+rootStruct.inner0.index 11
+rootStruct.inner1.index 12
+rootStruct.innerArr[1]
+rootStruct.innerArr[0].boolVal true
+rootStruct.innerArr[0].stringVal "deep"
+
+myarray[2]
+myarray[0].intval -5
+myarray[0].stringval[2]
+myarray[0].stringval[0] "baah"
+myarray[0].stringval[1] "yikes"
+myarray[0].enumval INNER
+myarray[0].refval :parent:
+myarray[0].fileVal "file0"
+myarray[0].anotherarray[1]
+myarray[0].anotherarray[0].foo 7
+myarray[0].myStruct.a 1
+myarray[0].myStruct.b 2
+myarray[1].intval 5
+myarray[1].stringval[0]
+myarray[1].enumval INNER
+myarray[1].refval ":parent:"
+myarray[1].fileVal "file1"
+myarray[1].anotherarray[2]
+myarray[1].anotherarray[0].foo 1
+myarray[1].anotherarray[1].foo 2
+myarray[1].myStruct.a -1
+myarray[1].myStruct.b -2
diff --git a/config/src/tests/functiontest/functiontest.cpp b/config/src/tests/functiontest/functiontest.cpp
new file mode 100644
index 00000000000..6541e76e06a
--- /dev/null
+++ b/config/src/tests/functiontest/functiontest.cpp
@@ -0,0 +1,304 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/fastos/fastos.h>
+#include <vespa/config/config.h>
+#include "config-function-test.h"
+
+#include <fstream>
+#include <vespa/log/log.h>
+#include <vespa/vespalib/testkit/testapp.h>
+#include <vespa/vespalib/data/slime/slime.h>
+
+LOG_SETUP("functiontest_test");
+
+using namespace config;
+
+namespace {
+
+void
+checkVariableAccess(const FunctionTestConfig & config)
+{
+    EXPECT_EQUAL(false, config.boolVal);
+    EXPECT_EQUAL(true, config.boolWithDef);
+    EXPECT_EQUAL(5, config.intVal);
+    EXPECT_EQUAL(-14, config.intWithDef);
+    EXPECT_EQUAL(12345678901LL, config.longVal);
+    EXPECT_EQUAL(-9876543210LL, config.longWithDef);
+    EXPECT_APPROX(41.23, config.doubleVal, 0.000001);
+    EXPECT_APPROX(-12, config.doubleWithDef, 0.000001);
+    EXPECT_EQUAL("foo", config.stringVal);
+    EXPECT_EQUAL("bar", config.stringwithdef);
+    EXPECT_EQUAL("FOOBAR", FunctionTestConfig::getEnumValName(config.enumVal));
+    EXPECT_EQUAL("BAR2",
+               FunctionTestConfig::getEnumwithdefName(config.enumwithdef));
+    EXPECT_EQUAL(":parent:", config.refval);
+    EXPECT_EQUAL(":parent:", config.refwithdef);
+    EXPECT_EQUAL("etc", config.fileVal);
+    EXPECT_EQUAL(1u, config.boolarr.size());
+    EXPECT_EQUAL(0u, config.intarr.size());
+    EXPECT_EQUAL(2u, config.longarr.size());
+    LOG(error, "0: %" PRId64, config.longarr[0]);
+    LOG(error, "1: %" PRId64, config.longarr[1]);
+    EXPECT_EQUAL(std::numeric_limits<int64_t>::max(), config.longarr[0]);
+    EXPECT_EQUAL(std::numeric_limits<int64_t>::min(), config.longarr[1]);
+    EXPECT_EQUAL(2u, config.doublearr.size());
+    EXPECT_EQUAL(1u, config.stringarr.size());
+    EXPECT_EQUAL(1u, config.enumarr.size());
+    EXPECT_EQUAL(3u, config.refarr.size());
+    EXPECT_EQUAL(1u, config.fileArr.size());
+    EXPECT_EQUAL("bin", config.fileArr[0]);
+
+    EXPECT_EQUAL("basicFoo", config.basicStruct.foo);
+    EXPECT_EQUAL(3, config.basicStruct.bar);
+    EXPECT_EQUAL(1u, config.basicStruct.intArr.size());
+    EXPECT_EQUAL(310, config.basicStruct.intArr[0]);
+    EXPECT_EQUAL("inner0", config.rootStruct.inner0.name);
+    EXPECT_EQUAL(11, config.rootStruct.inner0.index);
+    EXPECT_EQUAL("inner1", config.rootStruct.inner1.name);
+    EXPECT_EQUAL(12, config.rootStruct.inner1.index);
+    EXPECT_EQUAL(1u, config.rootStruct.innerArr.size());
+    EXPECT_EQUAL(true, config.rootStruct.innerArr[0].boolVal);
+    EXPECT_EQUAL("deep", config.rootStruct.innerArr[0].stringVal);
+
+    // TODO: replace ':parent:' with 'configId' when references are handled properly also in C++.
+    EXPECT_EQUAL(2u, config.myarray.size());
+    EXPECT_EQUAL(":parent:", config.myarray[0].refval);
+    EXPECT_EQUAL("file0", config.myarray[0].fileVal);
+    EXPECT_EQUAL(1, config.myarray[0].myStruct.a);
+    EXPECT_EQUAL(2, config.myarray[0].myStruct.b);
+    EXPECT_EQUAL(":parent:", config.myarray[1].refval);
+    EXPECT_EQUAL("file1", config.myarray[1].fileVal);
+    EXPECT_EQUAL(-1, config.myarray[1].myStruct.a);
+    EXPECT_EQUAL(-2, config.myarray[1].myStruct.b);
+}
+
+std::string
+readFile(const std::string & fileName)
+{
+    std::ifstream f(fileName.c_str());
+    ASSERT_FALSE(f.fail());
+    std::string content;
+    std::string line;
+    while (getline(f, line)) {
+        content += line;
+    }
+    return content;
+}
+
+}
+
+struct LazyTestFixture
+{
+    const DirSpec _spec;
+    ConfigSubscriber _subscriber;
+    ConfigHandle<FunctionTestConfig>::UP _handle;
+    std::unique_ptr<FunctionTestConfig> _config;
+
+    LazyTestFixture(const std::string & dirName)
+        : _spec(dirName),
+          _subscriber(_spec),
+          _handle(_subscriber.subscribe<FunctionTestConfig>(""))
+    {
+    }
+};
+
+struct TestFixture : public LazyTestFixture
+{
+    TestFixture(const std::string & dirName)
+        : LazyTestFixture(dirName)
+    {
+        ASSERT_TRUE(_subscriber.nextConfig(0));
+        _config = _handle->getConfig();
+    }
+};
+
+struct ErrorFixture
+{
+    LazyTestFixture & f;
+    ErrorFixture(LazyTestFixture & f1) : f(f1) { }
+    void run() {
+        f._subscriber.nextConfig(0);
+        bool thrown = false;
+        try {
+            f._handle->getConfig();
+        } catch (const InvalidConfigException & e) {
+            thrown = true;
+            LOG(info, "Error: %s", e.getMessage().c_str());
+        }
+        ASSERT_TRUE(thrown);
+    }
+};
+
+void attemptLacking(const std::string& param, bool isArray) {
+    std::ifstream in("defaultvalues/function-test.cfg", std::ios_base::in);
+    std::ostringstream config;
+    std::string s;
+    while (std::getline(in, s)) {
+        if (s.size() > param.size() &&
+            s.substr(0, param.size()) == param &&
+            (s[param.size()] == ' ' || s[param.size()] == '['))
+        {
+            // Ignore values matched
+        } else {
+            config << s << "\n";
+
+        }
+    }
+    //std::cerr << "Config lacking " << param << "\n"
+    //          << config.str() << "\n";
+    try{
+        RawSpec spec(config.str());
+        ConfigSubscriber subscriber(spec);
+        ConfigHandle<FunctionTestConfig>::UP handle = subscriber.subscribe<FunctionTestConfig>("foo");
+        ASSERT_TRUE(subscriber.nextConfig(0));
+        std::unique_ptr<FunctionTestConfig> cfg = handle->getConfig();
+        if (isArray) {
+            // Arrays are empty by default
+            return;
+        }
+        TEST_FATAL(("Expected to fail when not specifying value " + param
+                + " without default").c_str());
+    } catch (InvalidConfigException& e) {
+        if (isArray) {
+            TEST_FATAL("Arrays should be empty by default.");
+        }
+    }
+}
+
+TEST_F("testVariableAccess", TestFixture("variableaccess")) {
+    checkVariableAccess(*f._config);
+}
+
+
+TEST("test variable access from slime") {
+    vespalib::Slime slime;
+    std::string json(readFile("slime-payload.json"));
+    vespalib::slime::JsonFormat::decode(json, slime);
+    FunctionTestConfig config(config::ConfigPayload(slime.get()));
+    checkVariableAccess(config);
+}
+
+TEST_F("testDefaultValues", TestFixture("defaultvalues")) {
+    EXPECT_EQUAL(false, f._config->boolVal);
+    EXPECT_EQUAL(false, f._config->boolWithDef);
+    EXPECT_EQUAL(5, f._config->intVal);
+    EXPECT_EQUAL(-545, f._config->intWithDef);
+    EXPECT_EQUAL(1234567890123LL, f._config->longVal);
+    EXPECT_EQUAL(-50000000000LL, f._config->longWithDef);
+    EXPECT_APPROX(41.23, f._config->doubleVal, 0.000001);
+    EXPECT_APPROX(-6.43, f._config->doubleWithDef, 0.000001);
+    EXPECT_EQUAL("foo", f._config->stringVal);
+    EXPECT_EQUAL("foobar", f._config->stringwithdef);
+    EXPECT_EQUAL("FOOBAR", FunctionTestConfig::getEnumValName(f._config->enumVal));
+    EXPECT_EQUAL("BAR2",
+               FunctionTestConfig::getEnumwithdefName(f._config->enumwithdef));
+    EXPECT_EQUAL(":parent:", f._config->refval);
+    EXPECT_EQUAL(":parent:", f._config->refwithdef);
+    EXPECT_EQUAL("vespa.log", f._config->fileVal);
+    EXPECT_EQUAL(1u, f._config->boolarr.size());
+    EXPECT_EQUAL(0u, f._config->intarr.size());
+    EXPECT_EQUAL(0u, f._config->longarr.size());
+    EXPECT_EQUAL(2u, f._config->doublearr.size());
+    EXPECT_EQUAL(1u, f._config->stringarr.size());
+    EXPECT_EQUAL(1u, f._config->enumarr.size());
+    EXPECT_EQUAL(0u, f._config->refarr.size());
+    EXPECT_EQUAL(0u, f._config->fileArr.size());
+
+    EXPECT_EQUAL(3, f._config->basicStruct.bar);
+    EXPECT_EQUAL(1u, f._config->basicStruct.intArr.size());
+    EXPECT_EQUAL(10, f._config->basicStruct.intArr[0]);
+    EXPECT_EQUAL(11, f._config->rootStruct.inner0.index);
+    EXPECT_EQUAL(12, f._config->rootStruct.inner1.index);
+    EXPECT_EQUAL(1u, f._config->rootStruct.innerArr.size());
+    EXPECT_EQUAL("deep", f._config->rootStruct.innerArr[0].stringVal);
+
+    EXPECT_EQUAL(2u, f._config->myarray.size());
+    EXPECT_EQUAL(1, f._config->myarray[0].myStruct.a);
+    EXPECT_EQUAL(-1, f._config->myarray[1].myStruct.a);
+    EXPECT_EQUAL("command.com", f._config->myarray[0].fileVal);
+    EXPECT_EQUAL("display.sys", f._config->myarray[1].fileVal);
+}
+
+TEST("testLackingDefaults") {
+    attemptLacking("bool_val", false);
+    attemptLacking("int_val", false);
+    attemptLacking("long_val", false);
+    attemptLacking("double_val", false);
+    attemptLacking("string_val", false);
+    attemptLacking("enum_val", false);
+    attemptLacking("refval", false);
+    attemptLacking("fileVal", false);
+
+    attemptLacking("boolarr", true);
+    attemptLacking("intarr", true);
+    attemptLacking("longarr", true);
+    attemptLacking("doublearr", true);
+    attemptLacking("enumarr", true);
+    attemptLacking("stringarr", true);
+    attemptLacking("refarr", true);
+    attemptLacking("fileArr", true);
+    attemptLacking("myarray", true);
+
+    attemptLacking("basicStruct.bar", false);
+    attemptLacking("rootStruct.inner0.index", false);
+    attemptLacking("rootStruct.inner1.index", false);
+
+    // NOTE: When this line is lacking in C++, the array will be empty, and no exception is thrown. In Java, the array
+    //       is initialized to length 1 (by the preceeding line 'rootStruct.innerArr[1]'), and an exception is thrown
+    //       when the value is lacking.
+    attemptLacking("rootStruct.innerArr[0].stringVal", true);
+
+    attemptLacking("myarray[0].stringval", true);
+    attemptLacking("myarray[0].refval", false);
+    attemptLacking("myarray[0].anotherarray", true);
+    attemptLacking("myarray[0].anotherarray", true);
+    attemptLacking("myarray[0].myStruct.a", false);
+}
+
+TEST_F("testRandomOrder", TestFixture("randomorder")) {
+    EXPECT_EQUAL(false, f._config->boolVal);
+    EXPECT_EQUAL(true, f._config->boolWithDef);
+    EXPECT_EQUAL(5, f._config->intVal);
+    EXPECT_EQUAL(-14, f._config->intWithDef);
+    EXPECT_EQUAL(666000666000LL, f._config->longVal);
+    EXPECT_EQUAL(-333000333000LL, f._config->longWithDef);
+    EXPECT_APPROX(41.23, f._config->doubleVal, 0.000001);
+    EXPECT_APPROX(-12, f._config->doubleWithDef, 0.000001);
+    EXPECT_EQUAL("foo", f._config->stringVal);
+    EXPECT_EQUAL("bar", f._config->stringwithdef);
+    EXPECT_EQUAL("FOOBAR", FunctionTestConfig::getEnumValName(f._config->enumVal));
+    EXPECT_EQUAL("BAR2",
+    FunctionTestConfig::getEnumwithdefName(f._config->enumwithdef));
+    EXPECT_EQUAL(":parent:", f._config->refval);
+    EXPECT_EQUAL(":parent:", f._config->refwithdef);
+    EXPECT_EQUAL("autoexec.bat", f._config->fileVal);
+    EXPECT_EQUAL(1u, f._config->boolarr.size());
+    EXPECT_EQUAL(0u, f._config->intarr.size());
+    EXPECT_EQUAL(0u, f._config->longarr.size());
+    EXPECT_EQUAL(2u, f._config->doublearr.size());
+    EXPECT_EQUAL(1u, f._config->stringarr.size());
+    EXPECT_EQUAL(1u, f._config->enumarr.size());
+    EXPECT_EQUAL(0u, f._config->refarr.size());
+    EXPECT_EQUAL(0u, f._config->fileArr.size());
+    EXPECT_EQUAL(2u, f._config->myarray.size());
+}
+
+TEST_FF("testErrorRangeInt32", LazyTestFixture("errorval_int"), ErrorFixture(f1)) { f2.run(); }
+TEST_FF("testErrorRangeInt64", LazyTestFixture("errorval_long"), ErrorFixture(f1)) { f2.run(); }
+TEST_FF("testErrorRangeDouble", LazyTestFixture("errorval_double"), ErrorFixture(f1)) { f2.run(); }
+
+#if 0
+TEST_F("testEquality", TestFixture("variableaccess")) {
+    FunctionTestConfig myconfig(*f._config);
+    EXPECT_EQUAL(_config, myconfig);
+    myconfig.intVal = 2;
+    EXPECT_TRUE(_config != myconfig);
+    EXPECT_TRUE(_config.myarray == myconfig.myarray);
+    myconfig.myarray[1].anotherarray[1].foo = 5;
+    EXPECT_TRUE(_config.myarray != myconfig.myarray);
+    EXPECT_EQUAL(_config.myarray[0], myconfig.myarray[0]);
+    EXPECT_EQUAL(_config.myarray[1].refval, myconfig.myarray[1].refval);
+}
+#endif
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/functiontest/missingvalue/function-test.cfg b/config/src/tests/functiontest/missingvalue/function-test.cfg
new file mode 100644
index 00000000000..9616ac3d27b
--- /dev/null
+++ b/config/src/tests/functiontest/missingvalue/function-test.cfg
@@ -0,0 +1,39 @@
+bool_val false
+long_val 123
+double_val 41.23
+string_val "foo"
+enum_val FOOBAR
+refval ":parent:"
+fileVal "msdos.sys"
+boolarr[1]
+boolarr[0] false
+intarr[0]
+longarr[0]
+doublearr[2]
+doublearr[0] 2344
+doublearr[1] 123
+stringarr[1]
+stringarr[0] "bar"
+enumarr[1]
+enumarr[0] VALUES
+refarr[0]
+basicStruct.bar 3
+rootStruct.inner0.index 11
+rootStruct.inner1.index 12
+rootStruct.innerArr[0]
+myarray[2]
+myarray[0].stringval[2]
+myarray[0].stringval[0] "baah"
+myarray[0].stringval[1] "yikes"
+myarray[0].refval ":parent:"
+myarray[0].fileVal "command.com"
+myarray[0].anotherarray[1]
+myarray[0].anotherarray[0].foo 7
+myarray[0].myStruct.a 1
+myarray[1].stringval[0]
+myarray[1].refval ":parent:"
+myarray[1].fileVal "display.sys"
+myarray[1].anotherarray[2]
+myarray[1].anotherarray[0].foo 1
+myarray[1].anotherarray[1].foo 2
+myarray[1].myStruct.a 1
diff --git a/config/src/tests/functiontest/randomorder/function-test.cfg b/config/src/tests/functiontest/randomorder/function-test.cfg
new file mode 100644
index 00000000000..d3ec59491d2
--- /dev/null
+++ b/config/src/tests/functiontest/randomorder/function-test.cfg
@@ -0,0 +1,55 @@
+boolarr[1]
+boolarr[0] false
+int_with_def -14
+double_val 41.23
+double_with_def -12
+enumwithdef BAR2
+refval ":parent:"
+refwithdef ":parent:"
+intarr[0]
+basicStruct.intArr[1]
+basicStruct.intArr[0] 10
+doublearr[2]
+doublearr[0] 2344
+doublearr[1] 123
+string_val "foo"
+stringwithdef "bar"
+enum_val FOOBAR
+stringarr[1]
+stringarr[0] "bar"
+basicStruct.bar 3
+long_with_def -333000333000
+enumarr[1]
+enumarr[0] VALUES
+refarr[0]
+rootStruct.innerArr[1]
+rootStruct.innerArr[0].stringVal "deep"
+fileVal "autoexec.bat"
+myarray[2]
+myarray[0].intval -5
+myarray[0].myStruct.a 1
+myarray[0].enumval INNER
+myarray[0].refval ":parent:"
+myarray[0].anotherarray[1]
+myarray[0].anotherarray[0].foo 7
+myarray[0].stringval[2]
+myarray[0].stringval[0] "baah"
+myarray[0].stringval[1] "yikes"
+myarray[0].fileVal "file0"
+myarray[1].stringval[0]
+myarray[1].enumval INNER
+myarray[1].anotherarray[2]
+myarray[1].anotherarray[0].foo 1
+myarray[1].anotherarray[1].foo 2
+myarray[1].myStruct.a -1
+myarray[1].refval ":parent:"
+myarray[1].intval 5
+myarray[1].fileVal "file1"
+bool_val false
+bool_with_def true
+longarr[0]
+rootStruct.inner1.index 12
+int_val 5
+rootStruct.inner0.index 11
+long_val 666000666000
+fileArr[0]
diff --git a/config/src/tests/functiontest/slime-payload.json b/config/src/tests/functiontest/slime-payload.json
new file mode 100644
index 00000000000..7e3a16e69eb
--- /dev/null
+++ b/config/src/tests/functiontest/slime-payload.json
@@ -0,0 +1,103 @@
+{
+    "bool_val": false,
+    "bool_with_def": true,
+    "int_val": 5,
+    "int_with_def": -14,
+    "long_val": 12345678901,
+    "long_with_def": -9876543210,
+    "double_val": 41.23,
+    "double_with_def": -12,
+    "string_val": "foo",
+    "stringwithdef": "bar",
+    "enum_val": "FOOBAR",
+    "enumwithdef": "BAR2",
+    "refval": ":parent:",
+    "refwithdef": ":parent:",
+    "fileVal": "etc",
+    "boolarr": [
+        false
+    ],
+    "intarr": [],
+    "longarr": [
+        9223372036854775807,
+        -9223372036854775808
+    ],
+    "doublearr": [
+        2344,
+        123
+    ],
+    "stringarr": [
+        "bar"
+    ],
+    "enumarr": [
+        "VALUES"
+    ],
+    "refarr": [
+        ":parent:",
+        ":parent:",
+        ":parent:"
+    ],
+    "fileArr": [
+        "bin"
+    ],
+    "basicStruct": {
+        "foo": "basicFoo",
+        "bar": 3,
+        "intArr": [
+            310
+        ]
+    },
+    "rootStruct": {
+        "inner0": {
+            "index": 11
+        },
+        "inner1": {
+            "index": 12
+        },
+        "innerArr": [
+            {
+                "boolVal": true,
+                "stringVal": "deep"
+            }
+        ]
+    },
+    "myarray": [
+        {
+            "intval": -5,
+            "stringval": [
+                "baah",
+                "yikes"
+            ],
+            "enumval": "INNER",
+            "refval": ":parent:",
+            "fileVal": "file0",
+            "anotherarray": [
+                {
+                    "foo": 7
+                }
+            ],
+            "myStruct": {
+                "a": 1,
+                "b": 2
+            }
+        },
+        {
+            "intval": 5,
+            "enumval": "INNER",
+            "refval": ":parent:",
+            "fileVal": "file1",
+            "anotherarray": [
+                {
+                    "foo": 1
+                },
+                {
+                    "foo": 2
+                }
+            ],
+            "myStruct": {
+                "a": -1,
+                "b": -2
+            }
+        }
+    ]
+}
diff --git a/config/src/tests/functiontest/variableaccess/function-test.cfg b/config/src/tests/functiontest/variableaccess/function-test.cfg
new file mode 100644
index 00000000000..d15bae0b764
--- /dev/null
+++ b/config/src/tests/functiontest/variableaccess/function-test.cfg
@@ -0,0 +1,67 @@
+bool_val false
+bool_with_def true
+int_val 5
+int_with_def -14
+long_val 12345678901
+long_with_def -9876543210
+double_val 41.23
+double_with_def -12
+string_val "foo"
+stringwithdef "bar"
+enum_val FOOBAR
+enumwithdef BAR2
+refval :parent:
+refwithdef ":parent:"
+fileVal "etc"
+boolarr[1]
+boolarr[0] false
+intarr[0]
+longarr[2]
+longarr[0] 9223372036854775807
+longarr[1] -9223372036854775808
+doublearr[2]
+doublearr[0] 2344
+doublearr[1] 123
+stringarr[1]
+stringarr[0] "bar"
+enumarr[1]
+enumarr[0] VALUES
+refarr[3]
+refarr[0] ":parent:"
+refarr[1] ":parent"
+refarr[2] "parent:"
+fileArr[1]
+fileArr[0] "bin"
+
+basicStruct.foo "basicFoo"
+basicStruct.bar 3
+basicStruct.intArr[1]
+basicStruct.intArr[0] 310
+rootStruct.inner0.index 11
+rootStruct.inner1.index 12
+rootStruct.innerArr[1]
+rootStruct.innerArr[0].boolVal true
+rootStruct.innerArr[0].stringVal "deep"
+
+myarray[2]
+myarray[0].intval -5
+myarray[0].stringval[2]
+myarray[0].stringval[0] "baah"
+myarray[0].stringval[1] "yikes"
+myarray[0].enumval INNER
+myarray[0].refval :parent:
+myarray[0].fileVal "file0"
+myarray[0].anotherarray[1]
+myarray[0].anotherarray[0].foo 7
+myarray[0].myStruct.a 1
+myarray[0].myStruct.b 2
+myarray[1].intval 5
+myarray[1].stringval[0]
+myarray[1].enumval INNER
+myarray[1].refval ":parent:"
+myarray[1].fileVal "file1"
+myarray[1].anotherarray[2]
+myarray[1].anotherarray[0].foo 1
+myarray[1].anotherarray[1].foo 2
+myarray[1].myStruct.a -1
+myarray[1].myStruct.b -2
diff --git a/config/src/tests/functiontestng/defaultvalues/.gitignore b/config/src/tests/functiontestng/defaultvalues/.gitignore
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/tests/functiontestng/defaultvalues/.gitignore
diff --git a/config/src/tests/functiontestng/errorval_double/.gitignore b/config/src/tests/functiontestng/errorval_double/.gitignore
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/tests/functiontestng/errorval_double/.gitignore
diff --git a/config/src/tests/functiontestng/errorval_int/.gitignore b/config/src/tests/functiontestng/errorval_int/.gitignore
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/tests/functiontestng/errorval_int/.gitignore
diff --git a/config/src/tests/functiontestng/errorval_long/.gitignore b/config/src/tests/functiontestng/errorval_long/.gitignore
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/tests/functiontestng/errorval_long/.gitignore
diff --git a/config/src/tests/functiontestng/missingvalue/.gitignore b/config/src/tests/functiontestng/missingvalue/.gitignore
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/tests/functiontestng/missingvalue/.gitignore
diff --git a/config/src/tests/functiontestng/randomorder/.gitignore b/config/src/tests/functiontestng/randomorder/.gitignore
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/tests/functiontestng/randomorder/.gitignore
diff --git a/config/src/tests/functiontestng/variableaccess/.gitignore b/config/src/tests/functiontestng/variableaccess/.gitignore
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/tests/functiontestng/variableaccess/.gitignore
diff --git a/config/src/tests/getconfig/.gitignore b/config/src/tests/getconfig/.gitignore
new file mode 100644
index 00000000000..c1760471d5d
--- /dev/null
+++ b/config/src/tests/getconfig/.gitignore
@@ -0,0 +1,3 @@
+/config-my.cpp
+/config-my.h
+config_getconfig_test_app
diff --git a/config/src/tests/getconfig/CMakeLists.txt b/config/src/tests/getconfig/CMakeLists.txt
new file mode 100644
index 00000000000..f8ad5c2c7ed
--- /dev/null
+++ b/config/src/tests/getconfig/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_getconfig_test_app
+    SOURCES
+    getconfig.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_getconfig_test_app COMMAND config_getconfig_test_app)
+vespa_generate_config(config_getconfig_test_app ../../test/resources/configdefinitions/my.def)
diff --git a/config/src/tests/getconfig/getconfig.cpp b/config/src/tests/getconfig/getconfig.cpp
new file mode 100644
index 00000000000..ec350e3140b
--- /dev/null
+++ b/config/src/tests/getconfig/getconfig.cpp
@@ -0,0 +1,70 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/config.h>
+#include <vespa/config/raw/rawsource.h>
+#include "config-my.h"
+
+using namespace config;
+
+namespace {
+
+struct ConfigFixture {
+    MyConfigBuilder builder;
+    ConfigSet set;
+    ConfigContext::SP context;
+    ConfigFixture() : builder(), set(), context() {
+        set.addBuilder("cfgid", &builder);
+        context.reset(new ConfigContext(set));
+    }
+};
+
+} // namespace <unnamed>
+
+TEST("requireThatGetConfigReturnsCorrectConfig")
+{
+    RawSpec spec("myField \"foo\"\n");
+
+    std::unique_ptr<MyConfig> cfg = ConfigGetter<MyConfig>::getConfig("myid", spec);
+    ASSERT_TRUE(cfg.get() != NULL);
+    ASSERT_EQUAL("my", cfg->defName());
+    ASSERT_EQUAL("foo", cfg->myField);
+}
+
+
+TEST("requireThatGetConfigReturnsCorrectConfig")
+{
+    FileSpec spec("my.cfg");
+    std::unique_ptr<MyConfig> cfg = ConfigGetter<MyConfig>::getConfig("", spec);
+    ASSERT_TRUE(cfg.get() != NULL);
+    ASSERT_EQUAL("my", cfg->defName());
+    ASSERT_EQUAL("foobar", cfg->myField);
+}
+
+TEST_F("require that ConfigGetter can be used to obtain config generation", ConfigFixture) {
+    f1.builder.myField = "foo";
+    {
+        int64_t gen1;
+        int64_t gen2;
+        std::unique_ptr<MyConfig> cfg1 = ConfigGetter<MyConfig>::getConfig(gen1, "cfgid", f1.set);
+        std::unique_ptr<MyConfig> cfg2 = ConfigGetter<MyConfig>::getConfig(gen2, "cfgid", f1.context);
+        EXPECT_EQUAL(1, gen1);
+        EXPECT_EQUAL(1, gen2);
+        EXPECT_EQUAL("foo", cfg1.get()->myField);
+        EXPECT_EQUAL("foo", cfg2.get()->myField);
+    }
+    f1.builder.myField = "bar";
+    f1.context->reload();
+    {
+        int64_t gen1;
+        int64_t gen2;
+        std::unique_ptr<MyConfig> cfg1 = ConfigGetter<MyConfig>::getConfig(gen1, "cfgid", f1.set);
+        std::unique_ptr<MyConfig> cfg2 = ConfigGetter<MyConfig>::getConfig(gen2, "cfgid", f1.context);
+        EXPECT_EQUAL(1, gen1); // <-- NB: generation will not increase when using the builder set directly
+        EXPECT_EQUAL(2, gen2);
+        EXPECT_EQUAL("bar", cfg1.get()->myField);
+        EXPECT_EQUAL("bar", cfg2.get()->myField);
+    }
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/getconfig/my.cfg b/config/src/tests/getconfig/my.cfg
new file mode 100644
index 00000000000..6172609bdff
--- /dev/null
+++ b/config/src/tests/getconfig/my.cfg
@@ -0,0 +1 @@
+myField "foobar"
diff --git a/config/src/tests/getconfig/test1.cfg b/config/src/tests/getconfig/test1.cfg
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/tests/getconfig/test1.cfg
diff --git a/config/src/tests/legacysubscriber/.gitignore b/config/src/tests/legacysubscriber/.gitignore
new file mode 100644
index 00000000000..336ddd89dd5
--- /dev/null
+++ b/config/src/tests/legacysubscriber/.gitignore
@@ -0,0 +1,7 @@
+/config-bar.cpp
+/config-bar.h
+/config-foo.cpp
+/config-foo.h
+/config-my.cpp
+/config-my.h
+config_legacysubscriber_test_app
diff --git a/config/src/tests/legacysubscriber/CMakeLists.txt b/config/src/tests/legacysubscriber/CMakeLists.txt
new file mode 100644
index 00000000000..66022e31007
--- /dev/null
+++ b/config/src/tests/legacysubscriber/CMakeLists.txt
@@ -0,0 +1,11 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_legacysubscriber_test_app
+    SOURCES
+    legacysubscriber.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_legacysubscriber_test_app COMMAND config_legacysubscriber_test_app)
+vespa_generate_config(config_legacysubscriber_test_app ../../test/resources/configdefinitions/foo.def)
+vespa_generate_config(config_legacysubscriber_test_app ../../test/resources/configdefinitions/bar.def)
+vespa_generate_config(config_legacysubscriber_test_app ../../test/resources/configdefinitions/my.def)
diff --git a/config/src/tests/legacysubscriber/legacysubscriber.cpp b/config/src/tests/legacysubscriber/legacysubscriber.cpp
new file mode 100644
index 00000000000..966e12a0b82
--- /dev/null
+++ b/config/src/tests/legacysubscriber/legacysubscriber.cpp
@@ -0,0 +1,86 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/helper/legacysubscriber.h>
+#include <fstream>
+#include <config-my.h>
+#include <config-foo.h>
+#include <config-bar.h>
+
+using namespace config;
+
+template <typename ConfigType>
+class MyCallback : public IFetcherCallback<ConfigType>
+{
+public:
+    MyCallback() : _config(), _configured(false) { }
+    void configure(std::unique_ptr<ConfigType> config)
+    {
+        _configured = true;
+        _config = std::move(config);
+    }
+    std::unique_ptr<ConfigType> _config;
+    bool _configured;
+};
+
+TEST("requireThatFileLegacyWorks") {
+    LegacySubscriber s;
+    MyCallback<MyConfig> cb;
+    s.subscribe<MyConfig>("file:test1.cfg", &cb);
+    ASSERT_TRUE(cb._configured);
+    ASSERT_TRUE(cb._config.get() != NULL);
+    ASSERT_EQUAL("bar", cb._config->myField);
+}
+
+TEST("requireThatDirLegacyWorks") {
+    LegacySubscriber s;
+    MyCallback<MyConfig> cb;
+    s.subscribe<MyConfig>("dir:testdir", &cb);
+    ASSERT_TRUE(cb._configured);
+    ASSERT_TRUE(cb._config.get() != NULL);
+    ASSERT_EQUAL("bar", cb._config->myField);
+}
+
+
+TEST("requireThatDirMultiFileLegacyWorks") {
+    MyCallback<FooConfig> cb1;
+    MyCallback<BarConfig> cb2;
+
+    LegacySubscriber s1, s2;
+    s1.subscribe<FooConfig>("dir:testdir/foobar", &cb1);
+    s2.subscribe<BarConfig>("dir:testdir/foobar", &cb2);
+
+    ASSERT_TRUE(cb1._configured);
+    ASSERT_TRUE(cb1._config.get() != NULL);
+    ASSERT_EQUAL("bar", cb1._config->fooValue);
+
+    ASSERT_TRUE(cb2._configured);
+    ASSERT_TRUE(cb2._config.get() != NULL);
+    ASSERT_EQUAL("foo", cb2._config->barValue);
+}
+
+TEST("requireThatFileLegacyWorksMultipleTimes") {
+    LegacySubscriber s;
+    MyCallback<MyConfig> cb;
+    s.subscribe<MyConfig>("file:test1.cfg", &cb);
+    ASSERT_TRUE(cb._configured);
+    ASSERT_TRUE(cb._config.get() != NULL);
+    ASSERT_EQUAL("bar", cb._config->myField);
+    cb._configured = false;
+    LegacySubscriber s2;
+    s2.subscribe<MyConfig>("file:test1.cfg", &cb);
+    ASSERT_TRUE(cb._configured);
+    ASSERT_TRUE(cb._config.get() != NULL);
+    ASSERT_EQUAL("bar", cb._config->myField);
+}
+
+TEST("requireThatRawLegacyWorks") {
+    LegacySubscriber s;
+    MyCallback<MyConfig> cb;
+    s.subscribe<MyConfig>("raw:myField \"bar\"\n", &cb);
+    ASSERT_TRUE(cb._configured);
+    ASSERT_TRUE(cb._config.get() != NULL);
+    ASSERT_EQUAL("bar", cb._config->myField);
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/legacysubscriber/test1.cfg b/config/src/tests/legacysubscriber/test1.cfg
new file mode 100644
index 00000000000..4b0bbd13c83
--- /dev/null
+++ b/config/src/tests/legacysubscriber/test1.cfg
@@ -0,0 +1 @@
+myField "bar"
diff --git a/config/src/tests/legacysubscriber/testdir/foobar/bar.cfg b/config/src/tests/legacysubscriber/testdir/foobar/bar.cfg
new file mode 100644
index 00000000000..80d5b6f10b4
--- /dev/null
+++ b/config/src/tests/legacysubscriber/testdir/foobar/bar.cfg
@@ -0,0 +1 @@
+barValue "foo"
diff --git a/config/src/tests/legacysubscriber/testdir/foobar/foo.cfg b/config/src/tests/legacysubscriber/testdir/foobar/foo.cfg
new file mode 100644
index 00000000000..6ec74b85d6a
--- /dev/null
+++ b/config/src/tests/legacysubscriber/testdir/foobar/foo.cfg
@@ -0,0 +1 @@
+fooValue "bar"
diff --git a/config/src/tests/legacysubscriber/testdir/foobar/nothing.txt b/config/src/tests/legacysubscriber/testdir/foobar/nothing.txt
new file mode 100644
index 00000000000..e69de29bb2d
--- /dev/null
+++ b/config/src/tests/legacysubscriber/testdir/foobar/nothing.txt
diff --git a/config/src/tests/legacysubscriber/testdir/my.cfg b/config/src/tests/legacysubscriber/testdir/my.cfg
new file mode 100644
index 00000000000..4b0bbd13c83
--- /dev/null
+++ b/config/src/tests/legacysubscriber/testdir/my.cfg
@@ -0,0 +1 @@
+myField "bar"
diff --git a/config/src/tests/misc/.gitignore b/config/src/tests/misc/.gitignore
new file mode 100644
index 00000000000..d6c1f6760a4
--- /dev/null
+++ b/config/src/tests/misc/.gitignore
@@ -0,0 +1 @@
+config_misc_test_app
diff --git a/config/src/tests/misc/CMakeLists.txt b/config/src/tests/misc/CMakeLists.txt
new file mode 100644
index 00000000000..a37f6411e0b
--- /dev/null
+++ b/config/src/tests/misc/CMakeLists.txt
@@ -0,0 +1,8 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_misc_test_app
+    SOURCES
+    misc.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_misc_test_app COMMAND config_misc_test_app)
diff --git a/config/src/tests/misc/misc.cpp b/config/src/tests/misc/misc.cpp
new file mode 100644
index 00000000000..b2595599125
--- /dev/null
+++ b/config/src/tests/misc/misc.cpp
@@ -0,0 +1,194 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/common/configupdate.h>
+#include <vespa/config/common/misc.h>
+#include <vespa/config/common/configvalue.h>
+#include <vespa/config/common/errorcode.h>
+#include <vespa/config/common/vespa_version.h>
+#include <vespa/config/subscription/sourcespec.h>
+#include <vespa/vespalib/stllike/hash_map.h>
+#include <map>
+
+using namespace config;
+
+TEST("requireThatConfigUpdateWorks") {
+    std::vector<vespalib::string> lines;
+    lines.push_back("foo");
+
+    ConfigUpdate up(ConfigValue(lines, "mymd5"), true, 1337);
+    ASSERT_EQUAL(1337, up.getGeneration());
+    ASSERT_TRUE(up.hasChanged());
+
+    ConfigUpdate up2(ConfigValue(lines, "mymd52"), false, 1338);
+    ASSERT_EQUAL(1338, up2.getGeneration());
+    ASSERT_FALSE(up2.hasChanged());
+}
+
+TEST("requireThatConfigValueWorks") {
+    std::vector<vespalib::string> lines;
+    lines.push_back("myFooField \"bar\"");
+    ConfigValue v1(lines, calculateContentMd5(lines));
+    ConfigValue v2(lines, calculateContentMd5(lines));
+    ConfigValue v3(lines, calculateContentMd5(lines));
+    lines.push_back("myFooField \"bar2\"");
+    ConfigValue v4(lines, calculateContentMd5(lines));
+    ASSERT_TRUE(v1 == v2);
+    ASSERT_TRUE(v1 == v3);
+}
+
+TEST("requireThatConfigKeyWorks") {
+    ConfigKey key1("id1", "def1", "namespace1", "md51");
+    ConfigKey key2("id1", "def1", "namespace1", "md51");
+    ConfigKey key3("id2", "def1", "namespace1", "md51");
+    ConfigKey key4("id1", "def2", "namespace1", "md51");
+    ConfigKey key5("id1", "def1", "namespace2", "md51");
+    ConfigKey key6("id1", "def1", "namespace1", "md52"); // Special case. Md5 does not matter, so should be qual to key1 and key2
+
+    ASSERT_TRUE(key1 == key2);
+
+    ASSERT_TRUE(key1 == key1);
+    ASSERT_TRUE(key1 == key2);
+    ASSERT_TRUE(key1 < key3);
+    ASSERT_TRUE(key1 < key4);
+    ASSERT_TRUE(key1 < key5);
+    ASSERT_TRUE(key1 == key6);
+
+    ASSERT_TRUE(key2 == key1);
+    ASSERT_TRUE(key2 == key2);
+    ASSERT_TRUE(key2 < key3);
+    ASSERT_TRUE(key2 < key4);
+    ASSERT_TRUE(key2 < key5);
+    ASSERT_TRUE(key2 == key6);
+
+    ASSERT_TRUE(key3 > key1);
+    ASSERT_TRUE(key3 > key2);
+    ASSERT_TRUE(key3 == key3);
+    ASSERT_TRUE(key3 > key4);
+    ASSERT_TRUE(key3 > key5);
+    ASSERT_TRUE(key3 > key6);
+
+    ASSERT_TRUE(key4 > key1);
+    ASSERT_TRUE(key4 > key2);
+    ASSERT_TRUE(key4 < key3);
+    ASSERT_TRUE(key4 == key4);
+    ASSERT_TRUE(key4 > key5);
+    ASSERT_TRUE(key4 > key6);
+
+    ASSERT_TRUE(key5 > key1);
+    ASSERT_TRUE(key5 > key2);
+    ASSERT_TRUE(key5 < key3);
+    ASSERT_TRUE(key5 < key4);
+    ASSERT_TRUE(key5 == key5);
+    ASSERT_TRUE(key5 > key6);
+
+    ASSERT_TRUE(key6 == key1);
+    ASSERT_TRUE(key6 == key2); 
+    ASSERT_TRUE(key6 < key3);
+    ASSERT_TRUE(key6 < key4);
+    ASSERT_TRUE(key6 < key5);
+    ASSERT_TRUE(key6 == key6);
+
+    std::map<ConfigKey, int> keymap;
+    keymap[key1] = 1;
+    keymap[key2] = 2;
+    keymap[key3] = 3;
+    keymap[key4] = 4;
+    keymap[key5] = 5;
+
+    ASSERT_EQUAL(2, keymap[key1]);
+    ASSERT_EQUAL(2, keymap[key2]);
+    ASSERT_EQUAL(3, keymap[key3]);
+    ASSERT_EQUAL(4, keymap[key4]);
+    ASSERT_EQUAL(5, keymap[key5]);
+    keymap[key6] = 6;
+    ASSERT_EQUAL(6, keymap[key1]);
+    ASSERT_EQUAL(6, keymap[key2]);
+    ASSERT_EQUAL(6, keymap[key6]);
+}
+
+TEST("require that config key initializes schema")
+{
+    std::vector<vespalib::string> schema;
+    schema.push_back("foo");
+    schema.push_back("bar");
+    ConfigKey key("id1", "def1", "namespace1", "md51", schema);
+    const std::vector<vespalib::string> &vref(key.getDefSchema());
+    for (size_t i = 0; i < schema.size(); i++) {
+        ASSERT_EQUAL(schema[i], vref[i]);
+    }
+}
+
+TEST("require that error codes are correctly translated to strings") {
+#define ASSERT_CONFIG(name) ASSERT_EQUAL(#name, ErrorCode::getName(ErrorCode::name))
+    ASSERT_CONFIG(UNKNOWN_CONFIG);
+    ASSERT_CONFIG(UNKNOWN_DEFINITION);
+    ASSERT_CONFIG(UNKNOWN_VERSION);
+    ASSERT_CONFIG(UNKNOWN_CONFIGID);
+    ASSERT_CONFIG(UNKNOWN_DEF_MD5);
+    ASSERT_CONFIG(UNKNOWN_VESPA_VERSION);
+    ASSERT_CONFIG(ILLEGAL_NAME);
+    ASSERT_CONFIG(ILLEGAL_VERSION);
+    ASSERT_CONFIG(ILLEGAL_CONFIGID);
+    ASSERT_CONFIG(ILLEGAL_DEF_MD5);
+    ASSERT_CONFIG(ILLEGAL_CONFIG_MD5);
+    ASSERT_CONFIG(ILLEGAL_TIMEOUT);
+    ASSERT_CONFIG(ILLEGAL_TIMESTAMP);
+    ASSERT_CONFIG(ILLEGAL_NAME_SPACE);
+    ASSERT_CONFIG(ILLEGAL_PROTOCOL_VERSION);
+    ASSERT_CONFIG(ILLEGAL_CLIENT_HOSTNAME);
+    ASSERT_CONFIG(OUTDATED_CONFIG);
+    ASSERT_CONFIG(INTERNAL_ERROR);
+    ASSERT_CONFIG(APPLICATION_NOT_LOADED);
+    ASSERT_CONFIG(INCONSISTENT_CONFIG_MD5);
+    ASSERT_EQUAL("Unknown error", ErrorCode::getName(13434));
+#undef ASSERT_CONFIG
+}
+
+TEST("require that source spec parses protocol version") {
+    const char * envName = "VESPA_CONFIG_PROTOCOL_VERSION";
+    EXPECT_EQUAL(3, ServerSpec().protocolVersion());
+    setenv(envName, "2", 1);
+    EXPECT_EQUAL(2, ServerSpec().protocolVersion());
+    setenv(envName, "3", 1);
+    EXPECT_EQUAL(3, ServerSpec().protocolVersion());
+    setenv(envName, "4", 1);
+    EXPECT_EQUAL(3, ServerSpec().protocolVersion());
+    setenv(envName, "illegal", 1);
+    EXPECT_EQUAL(3, ServerSpec().protocolVersion());
+    setenv(envName, "1", 1);
+    EXPECT_EQUAL(1, ServerSpec().protocolVersion());
+    unsetenv(envName);
+}
+
+TEST("require that source spec parses trace level") {
+    const char * envName = "VESPA_CONFIG_PROTOCOL_TRACELEVEL";
+    EXPECT_EQUAL(0, ServerSpec().traceLevel());
+    setenv(envName, "3", 1);
+    EXPECT_EQUAL(3, ServerSpec().traceLevel());
+    setenv(envName, "illegal", 1);
+    EXPECT_EQUAL(0, ServerSpec().traceLevel());
+    unsetenv(envName);
+}
+
+TEST("require that source spec parses compression type") {
+    const char * envName = "VESPA_CONFIG_PROTOCOL_COMPRESSION";
+    EXPECT_TRUE(CompressionType::LZ4 == ServerSpec().compressionType());
+    setenv(envName, "UNCOMPRESSED", 1);
+    EXPECT_TRUE(CompressionType::UNCOMPRESSED == ServerSpec().compressionType());
+    setenv(envName, "illegal", 1);
+    EXPECT_TRUE(CompressionType::LZ4 == ServerSpec().compressionType());
+    setenv(envName, "LZ4", 1);
+    EXPECT_TRUE(CompressionType::LZ4 == ServerSpec().compressionType());
+    unsetenv(envName);
+}
+
+TEST("require that vespa version is set") {
+    VespaVersion vespaVersion = VespaVersion::getCurrentVersion();
+    vespalib::string str = vespaVersion.toString();
+
+    EXPECT_TRUE(str.length() > 0);
+}
+
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/payload_converter/.gitignore b/config/src/tests/payload_converter/.gitignore
new file mode 100644
index 00000000000..94504539459
--- /dev/null
+++ b/config/src/tests/payload_converter/.gitignore
@@ -0,0 +1 @@
+config_payload_converter_test_app
diff --git a/config/src/tests/payload_converter/CMakeLists.txt b/config/src/tests/payload_converter/CMakeLists.txt
new file mode 100644
index 00000000000..743486e7164
--- /dev/null
+++ b/config/src/tests/payload_converter/CMakeLists.txt
@@ -0,0 +1,8 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_payload_converter_test_app
+    SOURCES
+    payload_converter.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_payload_converter_test_app COMMAND config_payload_converter_test_app)
diff --git a/config/src/tests/payload_converter/payload_converter.cpp b/config/src/tests/payload_converter/payload_converter.cpp
new file mode 100644
index 00000000000..664683b651f
--- /dev/null
+++ b/config/src/tests/payload_converter/payload_converter.cpp
@@ -0,0 +1,81 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP("payload_converter");
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/common/payload_converter.h>
+
+using namespace config;
+using namespace vespalib;
+using namespace vespalib::slime;
+
+TEST("require that v2 payload leaf values can be converted to cfg format") {
+    Slime slime;
+    Cursor & root(slime.setObject());
+    root.setString("foo", "bar");
+    root.setLong("bar", 8);
+    root.setDouble("baz", 3.1);
+    root.setBool("quux", true);
+    PayloadConverter converter(root);
+    std::vector<vespalib::string> lines(converter.convert());
+    std::sort(lines.begin(), lines.end());
+    
+    ASSERT_EQUAL(4u, lines.size());
+    EXPECT_EQUAL("bar 8", lines[0]);
+    EXPECT_EQUAL("baz 3.1", lines[1]);
+    EXPECT_EQUAL("foo \"bar\"", lines[2]);
+    EXPECT_EQUAL("quux true", lines[3]);
+}
+
+TEST("require that v2 payload struct values can be converted to cfg format") {
+    Slime slime;
+    Cursor & root(slime.setObject());
+    Cursor & inner(root.setObject("obj"));
+    inner.setString("foo", "bar");
+    inner.setLong("bar", 8);
+    PayloadConverter converter(root);
+    std::vector<vespalib::string> lines(converter.convert());
+    std::sort(lines.begin(), lines.end());
+
+    ASSERT_EQUAL(2u, lines.size());
+    EXPECT_EQUAL("obj.bar 8", lines[0]);
+    EXPECT_EQUAL("obj.foo \"bar\"", lines[1]);
+}
+
+TEST("require that v2 payload array values can be converted to cfg format") {
+    Slime slime;
+    Cursor & root(slime.setObject());
+    Cursor & inner(root.setArray("arr"));
+    inner.addString("foo");
+    inner.addLong(8);
+    PayloadConverter converter(root);
+    std::vector<vespalib::string> lines(converter.convert());
+    ASSERT_EQUAL(2u, lines.size());
+    EXPECT_EQUAL("arr[0] \"foo\"", lines[0]);
+    EXPECT_EQUAL("arr[1] 8", lines[1]);
+}
+
+
+TEST("require that v2 payload nested structures can be converted to cfg format") {
+    Slime slime;
+    Cursor & root(slime.setObject());
+    Cursor & inner(root.setArray("arr"));
+    Cursor & obj1(inner.addObject());
+    Cursor & obj2(inner.addObject());
+    obj1.setString("foo", "bar");
+    obj2.setLong("bar", 5);
+    Cursor & inner2(root.setObject("obj"));
+    Cursor & innerArr(inner2.setArray("arr"));
+    Cursor & innerobj(innerArr.addObject());
+    Cursor & innerArr2(innerobj.setArray("arr2"));
+    innerArr2.addString("muhaha");
+    PayloadConverter converter(root);
+    std::vector<vespalib::string> lines(converter.convert());
+    std::sort(lines.begin(), lines.end());
+    ASSERT_EQUAL(3u, lines.size());
+    EXPECT_EQUAL("arr[0].foo \"bar\"", lines[0]);
+    EXPECT_EQUAL("arr[1].bar 5", lines[1]);
+    EXPECT_EQUAL("obj.arr[0].arr2[0] \"muhaha\"", lines[2]);
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/print/.gitignore b/config/src/tests/print/.gitignore
new file mode 100644
index 00000000000..662c2639f41
--- /dev/null
+++ b/config/src/tests/print/.gitignore
@@ -0,0 +1,12 @@
+/config-motd.cpp
+/config-motd.h
+/config-my.cpp
+/config-my.h
+/motd2.cfg
+/motd2.json
+/test_1.cfg
+/test_2.cfg
+/test_3.cfg
+/test_1.json
+/test_2.json
+config_print_test_app
diff --git a/config/src/tests/print/CMakeLists.txt b/config/src/tests/print/CMakeLists.txt
new file mode 100644
index 00000000000..7af3b842c50
--- /dev/null
+++ b/config/src/tests/print/CMakeLists.txt
@@ -0,0 +1,10 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_print_test_app
+    SOURCES
+    print.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_print_test_app COMMAND config_print_test_app)
+vespa_generate_config(config_print_test_app ../../test/resources/configdefinitions/my.def)
+vespa_generate_config(config_print_test_app ../../test/resources/configdefinitions/motd.def)
diff --git a/config/src/tests/print/motd.cfg b/config/src/tests/print/motd.cfg
new file mode 100644
index 00000000000..e7c8a0db095
--- /dev/null
+++ b/config/src/tests/print/motd.cfg
@@ -0,0 +1,23 @@
+intVal 1
+longVal 1
+doubleVal 2.3
+stringVal "foo"
+stringnulldef "foo"
+enumVal FOOBAR
+refVal "refVal"
+fileVal "fileVal"
+boolVal true
+boolarr[0] true
+boolarr[1] false
+myArray[2]
+myArray[0].stringVal[1]
+myArray[0].stringVal[0] "bla"
+myArray[0].refVal "habba"
+myArray[1].stringVal[1]
+myArray[1].stringVal[0] "blabla"
+myArray[1].refVal "nabba"
+myArray[1].anotherArray[1]
+myArray[1].anotherArray[0].foo 1337
+stringmap{"foo"} "bar"
+structmap{"foo"}.foo 3
+mapmap{"foo"}.map{"baz"}.bar 32
diff --git a/config/src/tests/print/print.cpp b/config/src/tests/print/print.cpp
new file mode 100644
index 00000000000..7faae087e74
--- /dev/null
+++ b/config/src/tests/print/print.cpp
@@ -0,0 +1,98 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/config.h>
+#include <vespa/config/print.h>
+#include <vespa/config/print/fileconfigreader.h>
+#include <vespa/config/print/istreamconfigreader.h>
+#include "config-my.h"
+#include "config-motd.h"
+
+using namespace config;
+
+template <typename T>
+struct RawFixture {
+    RawSpec spec;
+    std::unique_ptr<T> cfg;
+    RawFixture()
+        : spec("myField \"foo\"\n"),
+          cfg(ConfigGetter<T>::getConfig("test", spec))
+    { }
+};
+
+
+TEST_F("requireThatConfigIsWrittenToFile", RawFixture<MyConfig>) {
+    FileConfigWriter writer("test_1.json");
+    ASSERT_TRUE(writer.write(*f.cfg, JsonConfigFormatter()));
+    struct stat st;
+    int ret = stat("test_1.json", &st);
+    ASSERT_EQUAL(0, ret);
+    ASSERT_TRUE(st.st_size > 0);
+}
+
+TEST_F("requireThatCanPrintAsJson", RawFixture<MyConfig>) {
+    FileConfigWriter writer("test_2.json");
+    ASSERT_TRUE(writer.write(*f.cfg, JsonConfigFormatter()));
+    FileConfigReader<MyConfig> reader("test_2.json");
+    std::unique_ptr<MyConfig> cfg2 = reader.read(JsonConfigFormatter());
+    ASSERT_TRUE(*cfg2 == *f.cfg);
+}
+
+TEST_F("requireThatCanPrintToOstream", RawFixture<MyConfig>) {
+    std::ostringstream ss;
+    OstreamConfigWriter writer(ss);
+    ASSERT_TRUE(writer.write(*f.cfg));
+    ASSERT_EQUAL("myField \"foo\"\n", ss.str());
+}
+
+TEST_F("requireThatCanReadFromIstream", RawFixture<MyConfig>) {
+    std::stringstream ss;
+    ss << "myField \"foo\"\n";
+    IstreamConfigReader<MyConfig> reader(ss);
+    std::unique_ptr<MyConfig> cfg = reader.read();
+    ASSERT_EQUAL(std::string("foo"), cfg->myField);
+}
+
+TEST_F("requireThatCanPrintToAscii", RawFixture<MyConfig>) {
+    vespalib::asciistream ss;
+    AsciiConfigWriter writer(ss);
+    ASSERT_TRUE(writer.write(*f.cfg));
+    ASSERT_EQUAL("myField \"foo\"\n", ss.str());
+}
+
+TEST_F("requireThatCanPrintAsConfigFormat", RawFixture<MyConfig>) {
+    FileConfigWriter writer("test_3.cfg");
+    ASSERT_TRUE(writer.write(*f.cfg));
+    FileConfigReader<MyConfig> reader("test_3.cfg");
+    std::unique_ptr<MyConfig> cfg2 = reader.read();
+    ASSERT_TRUE(*cfg2 == *f.cfg);
+}
+
+TEST_F("require that invalid file throws exception", RawFixture<MyConfig>) {
+    FileConfigReader<MyConfig> reader("nonexistant.cfg");
+    EXPECT_EXCEPTION(reader.read(), vespalib::IllegalArgumentException, "Unable to open file");
+
+}
+
+TEST_F("requireThatCanLoadWrittenWithConfigFormat", RawFixture<MyConfig>) {
+    FileConfigWriter writer("test_3.cfg");
+    ASSERT_TRUE(writer.write(*f.cfg));
+    std::unique_ptr<MyConfig> cfg2 = ConfigGetter<MyConfig>::getConfig("test_3", FileSpec("test_3.cfg"));
+    ASSERT_TRUE(*cfg2 == *f.cfg);
+}
+
+TEST("requireThatAllFieldsArePrintedCorrectly") {
+    std::unique_ptr<MotdConfig> cfg = ConfigGetter<MotdConfig>::getConfig("motd", FileSpec("motd.cfg"));
+    FileConfigWriter writer("motd2.cfg");
+    ASSERT_TRUE(writer.write(*cfg, FileConfigFormatter()));
+    std::unique_ptr<MotdConfig> cfg2 = ConfigGetter<MotdConfig>::getConfig("motd2", FileSpec("motd2.cfg"));
+    ASSERT_TRUE(*cfg2 == *cfg);
+}
+
+TEST("require that reading cfg format throws exception") {
+    FileConfigReader<MyConfig> reader("test_1.json");
+    EXPECT_EXCEPTION(reader.read(FileConfigFormatter()), vespalib::IllegalArgumentException, "Reading cfg format is not supported");
+}
+
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/raw_subscription/.gitignore b/config/src/tests/raw_subscription/.gitignore
new file mode 100644
index 00000000000..bed4d45f522
--- /dev/null
+++ b/config/src/tests/raw_subscription/.gitignore
@@ -0,0 +1,3 @@
+/config-my.cpp
+/config-my.h
+config_raw_subscription_test_app
diff --git a/config/src/tests/raw_subscription/CMakeLists.txt b/config/src/tests/raw_subscription/CMakeLists.txt
new file mode 100644
index 00000000000..8f1431006e0
--- /dev/null
+++ b/config/src/tests/raw_subscription/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_raw_subscription_test_app
+    SOURCES
+    raw_subscription.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_raw_subscription_test_app COMMAND config_raw_subscription_test_app)
+vespa_generate_config(config_raw_subscription_test_app ../../test/resources/configdefinitions/my.def)
diff --git a/config/src/tests/raw_subscription/raw_subscription.cpp b/config/src/tests/raw_subscription/raw_subscription.cpp
new file mode 100644
index 00000000000..69cdaa3f0d3
--- /dev/null
+++ b/config/src/tests/raw_subscription/raw_subscription.cpp
@@ -0,0 +1,41 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/config.h>
+#include <vespa/config/common/configholder.h>
+#include <vespa/config/raw/rawsource.h>
+#include "config-my.h"
+
+using namespace config;
+
+TEST("require that raw spec can create source factory")
+{
+    RawSpec spec("myField \"foo\"\n");
+    SourceFactory::UP raw = spec.createSourceFactory(TimingValues());
+    ASSERT_TRUE(raw.get() != NULL);
+    IConfigHolder::SP holder(new ConfigHolder());
+    Source::UP src = raw->createSource(holder, ConfigKey("myid", "my", "bar", "foo"));
+    ASSERT_TRUE(src.get() != NULL);
+
+    src->getConfig();
+    ASSERT_TRUE(holder->poll());
+    ConfigUpdate::UP update(holder->provide());
+    ASSERT_TRUE(update.get() != NULL);
+    const ConfigValue & value(update->getValue());
+    ASSERT_EQUAL(1u, value.numLines());
+    ASSERT_EQUAL("myField \"foo\"", value.getLine(0));
+}
+
+TEST("requireThatRawSubscriptionReturnsCorrectConfig")
+{
+    RawSpec spec("myField \"foo\"\n");
+    ConfigSubscriber s(spec);
+    std::unique_ptr<ConfigHandle<MyConfig> > handle = s.subscribe<MyConfig>("myid");
+    s.nextConfig(0);
+    std::unique_ptr<MyConfig> cfg = handle->getConfig();
+    ASSERT_TRUE(cfg.get() != NULL);
+    ASSERT_EQUAL("foo", cfg->myField);
+    ASSERT_EQUAL("my", cfg->defName());
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/subscriber/.gitignore b/config/src/tests/subscriber/.gitignore
new file mode 100644
index 00000000000..1b93a34021a
--- /dev/null
+++ b/config/src/tests/subscriber/.gitignore
@@ -0,0 +1,7 @@
+/config-bar.cpp
+/config-bar.h
+/config-foo.cpp
+/config-foo.h
+/config-baz.cpp
+/config-baz.h
+config_subscriber_test_app
diff --git a/config/src/tests/subscriber/CMakeLists.txt b/config/src/tests/subscriber/CMakeLists.txt
new file mode 100644
index 00000000000..1b1673a2512
--- /dev/null
+++ b/config/src/tests/subscriber/CMakeLists.txt
@@ -0,0 +1,11 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_subscriber_test_app
+    SOURCES
+    subscriber.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_subscriber_test_app COMMAND config_subscriber_test_app)
+vespa_generate_config(config_subscriber_test_app ../../test/resources/configdefinitions/foo.def)
+vespa_generate_config(config_subscriber_test_app ../../test/resources/configdefinitions/bar.def)
+vespa_generate_config(config_subscriber_test_app ../../test/resources/configdefinitions/baz.def)
diff --git a/config/src/tests/subscriber/subscriber.cpp b/config/src/tests/subscriber/subscriber.cpp
new file mode 100644
index 00000000000..0d5d2698b42
--- /dev/null
+++ b/config/src/tests/subscriber/subscriber.cpp
@@ -0,0 +1,525 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/config.h>
+#include <vespa/config/common/misc.h>
+#include <vespa/config/common/configholder.h>
+#include <vespa/config/subscription/configsubscription.h>
+#include <fstream>
+#include "config-foo.h"
+#include "config-bar.h"
+#include "config-baz.h"
+
+using namespace config;
+using namespace vespalib;
+
+namespace {
+
+    ConfigValue createValue(const std::string & value)
+    {
+        std::vector< vespalib::string > lines;
+        lines.push_back(value);
+        return ConfigValue(lines, calculateContentMd5(lines));
+    }
+
+    ConfigValue createFooValue(const std::string & value)
+    {
+        return createValue("fooValue \"" + value + "\"");
+    }
+
+    ConfigValue createBarValue(const std::string & value)
+    {
+        return createValue("barValue \"" + value + "\"");
+    }
+
+    ConfigValue createBazValue(const std::string & value)
+    {
+        return createValue("bazValue \"" + value + "\"");
+    }
+
+    void verifyConfig(const std::string & expected, std::unique_ptr<FooConfig> cfg)
+    {
+        ASSERT_TRUE(cfg.get() != NULL);
+        ASSERT_EQUAL(expected, cfg->fooValue);
+    }
+
+    void verifyConfig(const std::string & expected, std::unique_ptr<BarConfig> cfg)
+    {
+        ASSERT_TRUE(cfg.get() != NULL);
+        ASSERT_EQUAL(expected, cfg->barValue);
+    }
+
+    void verifyConfig(const std::string & expected, std::unique_ptr<BazConfig> cfg)
+    {
+        ASSERT_TRUE(cfg.get() != NULL);
+        ASSERT_EQUAL(expected, cfg->bazValue);
+    }
+
+    class MySource : public Source
+    {
+        void getConfig() { }
+        void close() { }
+        void reload(int64_t gen) { (void) gen; }
+    };
+
+    class MyManager : public IConfigManager
+    {
+    public:
+
+        void unsubscribeAll()  { }
+        size_t numSubscribers() const { return 0; }
+
+
+        SubscriptionId idCounter;
+        std::vector<IConfigHolder::SP> _holders;
+        int numCancel;
+
+
+        MyManager() : idCounter(0), numCancel(0) { }
+
+        ConfigSubscription::SP subscribe(const ConfigKey & key, uint64_t timeoutInMillis) {
+            (void) timeoutInMillis;
+            IConfigHolder::SP holder(new ConfigHolder());
+            _holders.push_back(holder);
+
+            ConfigSubscription::SP s(new ConfigSubscription(0, key, holder, Source::UP(new MySource())));
+            return s;
+        }
+        void unsubscribe(const ConfigSubscription::SP & subscription) {
+            (void) subscription;
+            numCancel++;
+        }
+
+        void updateValue(size_t index, const ConfigValue & value, int64_t generation) {
+            ASSERT_TRUE(index < _holders.size());
+            _holders[index]->handle(ConfigUpdate::UP(new ConfigUpdate(value, true, generation)));
+        }
+
+        void updateGeneration(size_t index, int64_t generation) {
+            ASSERT_TRUE(index < _holders.size());
+            ConfigValue value;
+            // Give previous value just as API.
+            if (_holders[index]->poll()) {
+                value = _holders[index]->provide()->getValue();
+            }
+            _holders[index]->handle(ConfigUpdate::UP(new ConfigUpdate(value, false, generation)));
+        }
+
+        void reload(int64_t generation)
+        {
+            (void) generation;
+        }
+
+    };
+
+    class APIFixture : public IConfigContext
+    {
+    public:
+        MyManager & _m;
+        APIFixture(MyManager & m)
+            : _m(m)
+        {
+        }
+
+        APIFixture(const APIFixture & rhs)
+            : IConfigContext(rhs),
+              _m(rhs._m)
+        { }
+
+        IConfigManager & getManagerInstance() {
+            return _m;
+        }
+
+        IConfigManager & getManagerInstance(const SourceSpec & spec) {
+            (void) spec;
+            return getManagerInstance();
+        }
+
+        void reload() { }
+    };
+
+    struct StandardFixture {
+        MyManager & f1;
+        ConfigSubscriber s;
+        ConfigHandle<FooConfig>::UP h1;
+        ConfigHandle<BarConfig>::UP h2;
+
+        StandardFixture(MyManager & F1, APIFixture & F2) : f1(F1), s(IConfigContext::SP(new APIFixture(F2)))
+        {
+            h1 = s.subscribe<FooConfig>("myid");
+            h2 = s.subscribe<BarConfig>("myid");
+            f1.updateValue(0, createFooValue("foo"), 1);
+            f1.updateValue(1, createBarValue("bar"), 1);
+            ASSERT_TRUE(s.nextConfig(0));
+            verifyConfig("foo", h1->getConfig());
+            verifyConfig("bar", h2->getConfig());
+        }
+    };
+
+    struct SimpleFixture {
+        ConfigSet set;
+        FooConfigBuilder fooBuilder;
+        BarConfigBuilder barBuilder;
+        SimpleFixture() {
+            fooBuilder.fooValue = "bar";
+            barBuilder.barValue = "foo";
+            set.addBuilder("myid", &fooBuilder);
+            set.addBuilder("myid", &barBuilder);
+        }
+    };
+}
+
+TEST_F("requireThatSubscriberCanGetMultipleTypes", SimpleFixture()) {
+    ConfigSubscriber s(f.set);
+    ConfigHandle<FooConfig>::UP h1 = s.subscribe<FooConfig>("myid");
+    ConfigHandle<BarConfig>::UP h2 = s.subscribe<BarConfig>("myid");
+    ASSERT_TRUE(s.nextConfig(0));
+    std::unique_ptr<FooConfig> foo = h1->getConfig();
+    std::unique_ptr<BarConfig> bar = h2->getConfig();
+    ASSERT_EQUAL("bar", foo->fooValue);
+    ASSERT_EQUAL("foo", bar->barValue);
+}
+
+TEST_F("requireThatNextConfigMustBeCalled", SimpleFixture()) {
+    ConfigSubscriber s(f.set);
+    ConfigHandle<FooConfig>::UP h1 = s.subscribe<FooConfig>("myid");
+    bool thrown = false;
+    try {
+        std::unique_ptr<FooConfig> foo = h1->getConfig();
+    } catch (const ConfigRuntimeException & e) {
+        thrown = true;
+    }
+    ASSERT_TRUE(thrown);
+}
+
+TEST_F("requireThatSubscriptionsCannotBeAddedWhenFrozen", SimpleFixture()) {
+    ConfigSubscriber s(f.set);
+    ConfigHandle<FooConfig>::UP h1 = s.subscribe<FooConfig>("myid");
+    ASSERT_TRUE(s.nextConfig(0));
+    bool thrown = false;
+    try {
+        ConfigHandle<BarConfig>::UP h2 = s.subscribe<BarConfig>("myid");
+    } catch (const ConfigRuntimeException & e) {
+        thrown = true;
+    }
+    ASSERT_TRUE(thrown);
+}
+
+TEST_FF("requireThatNextConfigReturnsFalseUntilSubscriptionHasSucceeded", MyManager, APIFixture(f1)) {
+    ConfigSubscriber s(IConfigContext::SP(new APIFixture(f2)));
+    ConfigHandle<FooConfig>::UP h1 = s.subscribe<FooConfig>("myid");
+    ConfigHandle<BarConfig>::UP h2 = s.subscribe<BarConfig>("myid");
+    ASSERT_FALSE(s.nextConfig(0));
+    ASSERT_FALSE(s.nextConfig(100));
+    f1.updateValue(0, createFooValue("foo"), 1);
+    ASSERT_FALSE(s.nextConfig(100));
+    f1.updateValue(1, createBarValue("bar"), 1);
+    ASSERT_TRUE(s.nextConfig(100));
+}
+
+TEST_FFF("requireThatNewGenerationIsFetchedOnReload", MyManager, APIFixture(f1), StandardFixture(f1, f2)) {
+    verifyConfig("foo", f3.h1->getConfig());
+    verifyConfig("bar", f3.h2->getConfig());
+
+    ASSERT_FALSE(f3.s.nextConfig(1000));
+
+    verifyConfig("foo", f3.h1->getConfig());
+    verifyConfig("bar", f3.h2->getConfig());
+
+    f1.updateValue(0, createFooValue("foo2"), 3);
+    f1.updateValue(1, createBarValue("bar2"), 3);
+
+    ASSERT_TRUE(f3.s.nextConfig(1000));
+
+    verifyConfig("foo2", f3.h1->getConfig());
+    verifyConfig("bar2", f3.h2->getConfig());
+}
+
+TEST_FFF("requireThatAllConfigsMustGetTimestampUpdate", MyManager, APIFixture(f1), StandardFixture(f1, f2)) {
+    f1.updateValue(0, createFooValue("foo2"), 2);
+    ASSERT_FALSE(f3.s.nextConfig(100));
+    verifyConfig("foo", f3.h1->getConfig());
+    verifyConfig("bar", f3.h2->getConfig());
+
+    f1.updateValue(0, createFooValue("foo2"), 3);
+    f1.updateGeneration(1, 3);
+
+    ASSERT_TRUE(f3.s.nextConfig(0));
+    verifyConfig("foo2", f3.h1->getConfig());
+    verifyConfig("bar", f3.h2->getConfig());
+}
+
+TEST_FFF("requireThatNextConfigMaySucceedIfInTheMiddleOfConfigUpdate", MyManager, APIFixture(f1), StandardFixture(f1, f2)) {
+    f1.updateValue(0, createFooValue("foo2"), 2);
+    ASSERT_FALSE(f3.s.nextConfig(1000));
+    verifyConfig("foo", f3.h1->getConfig());
+    verifyConfig("bar", f3.h2->getConfig());
+
+    f1.updateGeneration(1, 2);
+    ASSERT_TRUE(f3.s.nextConfig(0));
+    verifyConfig("foo2", f3.h1->getConfig());
+    verifyConfig("bar", f3.h2->getConfig());
+}
+
+TEST_FFF("requireThatCorrectConfigIsReturnedAfterTimestampUpdate", MyManager, APIFixture(f1), StandardFixture(f1, f2)) {
+    f1.updateGeneration(0, 2);
+    f1.updateGeneration(1, 2);
+    ASSERT_FALSE(f3.s.nextConfig(1000));
+    verifyConfig("foo", f3.h1->getConfig());
+    verifyConfig("bar", f3.h2->getConfig());
+    ASSERT_TRUE(f3.s.nextGeneration(0));
+    verifyConfig("foo", f3.h1->getConfig());
+    verifyConfig("bar", f3.h2->getConfig());
+}
+
+TEST_MT_FFF("requireThatConfigIsReturnedWhenUpdatedDuringNextConfig", 2, MyManager, APIFixture(f1), StandardFixture(f1, f2)) {
+    if (thread_id == 0) {
+        FastOS_Time timer;
+        timer.SetNow();
+        ASSERT_TRUE(f3.s.nextConfig(10000));
+        ASSERT_TRUE(timer.MilliSecsToNow() > 250);
+        ASSERT_TRUE(timer.MilliSecsToNow() <= 5000);
+        verifyConfig("foo2", f3.h1->getConfig());
+        verifyConfig("bar", f3.h2->getConfig());
+    } else {
+        FastOS_Thread::Sleep(300);
+        f1.updateValue(0, createFooValue("foo2"), 2);
+        FastOS_Thread::Sleep(300);
+        f1.updateGeneration(1, 2);
+    }
+}
+
+TEST_FFF("requireThatConfigIsReturnedWhenUpdatedBeforeNextConfig", MyManager, APIFixture(f1), StandardFixture(f1, f2)) {
+    FastOS_Time timer;
+    timer.SetNow();
+    ASSERT_FALSE(f3.s.nextConfig(1000));
+    ASSERT_TRUE(timer.MilliSecsToNow() > 850);
+    f1.updateGeneration(0, 2);
+    f1.updateGeneration(1, 2);
+    timer.SetNow();
+    ASSERT_TRUE(f3.s.nextGeneration(10000));
+    ASSERT_TRUE(timer.MilliSecsToNow() <= 5000);
+    verifyConfig("foo", f3.h1->getConfig());
+    verifyConfig("bar", f3.h2->getConfig());
+}
+
+TEST_FFF("requireThatSubscriptionsAreUnsubscribedOnClose", MyManager, APIFixture(f1), StandardFixture(f1, f2)) {
+    ASSERT_FALSE(f3.s.isClosed());
+    f3.s.close();
+    ASSERT_TRUE(f3.s.isClosed());
+    ASSERT_EQUAL(2, f1.numCancel);
+}
+
+TEST_FFF("requireThatNothingCanBeCalledAfterClose", MyManager, APIFixture(f1), StandardFixture(f1, f2)) {
+    ASSERT_FALSE(f3.s.isClosed());
+    f3.s.close();
+    ASSERT_TRUE(f3.s.isClosed());
+    ASSERT_FALSE(f3.s.nextConfig(100));
+    bool thrown = false;
+    try {
+        f3.h1->getConfig();
+    } catch (const ConfigRuntimeException & e) {
+        thrown = true;
+    }
+    ASSERT_TRUE(thrown);
+}
+
+TEST_MT_FFF("requireThatNextConfigIsInterruptedOnClose", 2, MyManager, APIFixture(f1), StandardFixture(f1, f2)) {
+    if (thread_id == 0) {
+        FastOS_Time timer;
+        timer.SetNow();
+        ASSERT_FALSE(f3.s.nextConfig(5000));
+        ASSERT_TRUE(timer.MilliSecsToNow() >= 500.0);
+        ASSERT_TRUE(timer.MilliSecsToNow() < 60000.0);
+    } else {
+        FastOS_Thread::Sleep(1000);
+        f3.s.close();
+    }
+}
+
+TEST_FF("requireThatHandlesAreMarkedAsChanged", MyManager, APIFixture(f1)) {
+    ConfigSubscriber s(IConfigContext::SP(new APIFixture(f2)));
+    ConfigHandle<FooConfig>::UP h1 = s.subscribe<FooConfig>("myid2");
+    ConfigHandle<BarConfig>::UP h2 = s.subscribe<BarConfig>("myid2");
+    ASSERT_FALSE(s.nextConfig(0));
+
+    f1.updateValue(0, createFooValue("foo"), 1);
+    f1.updateValue(1, createFooValue("bar"), 1);
+    ASSERT_TRUE(s.nextConfig(100));
+    ASSERT_TRUE(h1->isChanged());
+    ASSERT_TRUE(h2->isChanged());
+
+    ASSERT_FALSE(s.nextConfig(100));
+    ASSERT_FALSE(h1->isChanged());
+    ASSERT_FALSE(h2->isChanged());
+    f1.updateValue(0, createFooValue("bar"), 2);
+    f1.updateGeneration(1, 2);
+    ASSERT_TRUE(s.nextConfig(100));
+    ASSERT_TRUE(h1->isChanged());
+    ASSERT_FALSE(h2->isChanged());
+}
+
+TEST_FF("requireThatNextGenerationMarksChanged", MyManager, APIFixture(f1)) {
+    ConfigSubscriber s(IConfigContext::SP(new APIFixture(f2)));
+    ConfigHandle<FooConfig>::UP h1 = s.subscribe<FooConfig>("myid2");
+    ConfigHandle<BarConfig>::UP h2 = s.subscribe<BarConfig>("myid2");
+    f1.updateValue(0, createFooValue("foo"), 1);
+    f1.updateValue(1, createFooValue("bar"), 1);
+    ASSERT_TRUE(s.nextGeneration(0));
+    ASSERT_TRUE(h1->isChanged());
+    ASSERT_TRUE(h2->isChanged());
+
+    f1.updateValue(0, createFooValue("bar"), 2);
+    f1.updateGeneration(1, 2);
+    ASSERT_TRUE(s.nextGeneration(0));
+    ASSERT_TRUE(h1->isChanged());
+    ASSERT_FALSE(h2->isChanged());
+
+    f1.updateGeneration(0, 3);
+    f1.updateGeneration(1, 3);
+    ASSERT_TRUE(s.nextGeneration(0));
+    ASSERT_FALSE(h1->isChanged());
+    ASSERT_FALSE(h2->isChanged());
+}
+
+TEST_FF("requireThatgetGenerationIsSet", MyManager, APIFixture(f1)) {
+    ConfigSubscriber s(IConfigContext::SP(new APIFixture(f2)));
+    ConfigHandle<FooConfig>::UP h1 = s.subscribe<FooConfig>("myid2");
+    ConfigHandle<BarConfig>::UP h2 = s.subscribe<BarConfig>("myid2");
+    f1.updateValue(0, createFooValue("foo"), 1);
+    f1.updateValue(1, createFooValue("bar"), 1);
+    ASSERT_TRUE(s.nextGeneration(0));
+    ASSERT_EQUAL(1, s.getGeneration());
+    ASSERT_TRUE(h1->isChanged());
+    ASSERT_TRUE(h2->isChanged());
+    ASSERT_FALSE(s.nextGeneration(0));
+    f1.updateGeneration(1, 2);
+    ASSERT_FALSE(s.nextGeneration(0));
+    ASSERT_EQUAL(1, s.getGeneration());
+    f1.updateGeneration(0, 2);
+    ASSERT_TRUE(s.nextGeneration(0));
+    ASSERT_EQUAL(2, s.getGeneration());
+}
+
+TEST_FFF("requireThatConfigHandleStillHasConfigOnTimestampUpdate", MyManager, APIFixture(f1), StandardFixture(f1, f2)) {
+    f1.updateGeneration(0, 2);
+    f1.updateGeneration(1, 2);
+    ASSERT_TRUE(f3.s.nextGeneration(0));
+    verifyConfig("foo", f3.h1->getConfig());
+    verifyConfig("bar", f3.h2->getConfig());
+}
+
+TEST_FF("requireThatTimeStamp0Works", MyManager, APIFixture(f1)) {
+    ConfigSubscriber s(IConfigContext::SP(new APIFixture(f2)));
+    ConfigHandle<BarConfig>::UP h2 = s.subscribe<BarConfig>("myid");
+    ConfigHandle<FooConfig>::UP h1 = s.subscribe<FooConfig>("myid");
+    ConfigHandle<BazConfig>::UP h3 = s.subscribe<BazConfig>("myid");
+    f1.updateValue(0, createBarValue("bar"), 0);
+    f1.updateValue(1, createFooValue("foo"), 0);
+    f1.updateValue(2, createBazValue("baz"), 0);
+    ASSERT_TRUE(s.nextConfig(0));
+    verifyConfig("bar", h2->getConfig());
+    verifyConfig("foo", h1->getConfig());
+    verifyConfig("baz", h3->getConfig());
+}
+
+TEST_FF("requireThatNextGenerationWorksWithManyConfigs", MyManager, APIFixture(f1)) {
+    ConfigSubscriber s(IConfigContext::SP(new APIFixture(f2)));
+    ConfigHandle<BarConfig>::UP h2 = s.subscribe<BarConfig>("myid");
+    ConfigHandle<FooConfig>::UP h1 = s.subscribe<FooConfig>("myid");
+    ConfigHandle<BazConfig>::UP h3 = s.subscribe<BazConfig>("myid");
+    f1.updateValue(0, createBarValue("bar"), 1);
+    f1.updateValue(1, createFooValue("foo"), 1);
+    f1.updateValue(2, createBazValue("baz"), 1);
+    ASSERT_TRUE(s.nextGeneration(100));
+    verifyConfig("bar", h2->getConfig());
+    verifyConfig("foo", h1->getConfig());
+    verifyConfig("baz", h3->getConfig());
+    int generation = 2;
+
+    f1.updateGeneration(0, generation);
+    ASSERT_FALSE(s.nextGeneration(0));
+    f1.updateGeneration(1, generation);
+    ASSERT_FALSE(s.nextGeneration(0));
+    f1.updateGeneration(2, generation);
+    ASSERT_TRUE(s.nextGeneration(100));
+
+    generation++;
+    f1.updateGeneration(0, generation);
+    ASSERT_FALSE(s.nextGeneration(0));
+    f1.updateGeneration(2, generation);
+    ASSERT_FALSE(s.nextGeneration(0));
+    f1.updateGeneration(1, generation);
+    ASSERT_TRUE(s.nextGeneration(100));
+
+    generation++;
+    f1.updateGeneration(1, generation);
+    ASSERT_FALSE(s.nextGeneration(0));
+    f1.updateGeneration(0, generation);
+    ASSERT_FALSE(s.nextGeneration(0));
+    f1.updateGeneration(2, generation);
+    ASSERT_TRUE(s.nextGeneration(100));
+
+    generation++;
+    f1.updateGeneration(1, generation);
+    ASSERT_FALSE(s.nextGeneration(0));
+    f1.updateGeneration(2, generation);
+    ASSERT_FALSE(s.nextGeneration(0));
+    f1.updateGeneration(0, generation);
+    ASSERT_TRUE(s.nextGeneration(100));
+
+    generation++;
+    f1.updateGeneration(2, generation);
+    ASSERT_FALSE(s.nextGeneration(0));
+    f1.updateGeneration(0, generation);
+    ASSERT_FALSE(s.nextGeneration(0));
+    f1.updateGeneration(1, generation);
+    ASSERT_TRUE(s.nextGeneration(100));
+
+    generation++;
+    f1.updateGeneration(2, generation);
+    ASSERT_FALSE(s.nextGeneration(0));
+    f1.updateGeneration(1, generation);
+    ASSERT_FALSE(s.nextGeneration(0));
+    f1.updateGeneration(0, generation);
+    ASSERT_TRUE(s.nextGeneration(100));
+}
+
+TEST_FF("requireThatConfigSubscriberHandlesProxyCache", MyManager, APIFixture(f1)) {
+    ConfigSubscriber s(IConfigContext::SP(new APIFixture(f2)));
+    ConfigHandle<FooConfig>::UP h1 = s.subscribe<FooConfig>("myid");
+    f1.updateValue(0, createFooValue("foo"), 1);
+    f1.updateGeneration(0, 2);
+    ASSERT_TRUE(s.nextConfig(0));
+    ASSERT_EQUAL(2, s.getGeneration());
+    ASSERT_TRUE(h1->isChanged());
+    verifyConfig("foo", h1->getConfig());
+
+    f1.updateGeneration(0, 3);
+    ASSERT_TRUE(s.nextGeneration(0));
+    ASSERT_EQUAL(3, s.getGeneration());
+    ASSERT_FALSE(h1->isChanged());
+    verifyConfig("foo", h1->getConfig());
+}
+
+TEST_MT_FF("requireThatConfigSubscriberWaitsUntilNextConfigSucceeds", 2, MyManager, APIFixture(f1)) {
+    if (thread_id == 0) {
+        ConfigSubscriber s(IConfigContext::SP(new APIFixture(f2)));
+        ConfigHandle<FooConfig>::UP h1 = s.subscribe<FooConfig>("myid");
+        f1.updateValue(0, createFooValue("foo"), 1);
+        ASSERT_TRUE(s.nextConfig(0));
+        f1.updateGeneration(0, 2);
+        ASSERT_FALSE(s.nextConfig(1000));
+        TEST_BARRIER();
+        ASSERT_TRUE(s.nextConfig(2000));
+        verifyConfig("foo2", h1->getConfig()); // First update is skipped
+    } else {
+        TEST_BARRIER();
+        FastOS_Thread::Sleep(1000);
+        f1.updateValue(0, createFooValue("foo2"), 3);
+    }
+}
+
+TEST_MAIN() {
+    TEST_RUN_ALL();
+}
diff --git a/config/src/tests/subscription/.gitignore b/config/src/tests/subscription/.gitignore
new file mode 100644
index 00000000000..65556950180
--- /dev/null
+++ b/config/src/tests/subscription/.gitignore
@@ -0,0 +1,3 @@
+/config-my.cpp
+/config-my.h
+config_subscription_test_app
diff --git a/config/src/tests/subscription/CMakeLists.txt b/config/src/tests/subscription/CMakeLists.txt
new file mode 100644
index 00000000000..bbc3546c1da
--- /dev/null
+++ b/config/src/tests/subscription/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_subscription_test_app
+    SOURCES
+    subscription.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_subscription_test_app COMMAND config_subscription_test_app)
+vespa_generate_config(config_subscription_test_app ../../test/resources/configdefinitions/my.def)
diff --git a/config/src/tests/subscription/subscription.cpp b/config/src/tests/subscription/subscription.cpp
new file mode 100644
index 00000000000..69cba9707fe
--- /dev/null
+++ b/config/src/tests/subscription/subscription.cpp
@@ -0,0 +1,119 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/common/misc.h>
+#include <vespa/config/common/configholder.h>
+#include <vespa/config/subscription/configsubscription.h>
+#include <config-my.h>
+
+using namespace config;
+
+namespace {
+
+    struct SourceFixture
+    {
+        int numClose;
+        int numGetConfig;
+        int numReload;
+        SourceFixture()
+            : numClose(0),
+              numGetConfig(0),
+              numReload(0)
+        { }
+    };
+
+    struct MySource : public Source
+    {
+        MySource(SourceFixture * src)
+            : source(src)
+        {}
+
+        void getConfig() { source->numGetConfig++; }
+        void close() { source->numClose++; }
+        void reload(int64_t gen) { (void) gen; source->numReload++; }
+
+        SourceFixture * source;
+    };
+
+    struct SubscriptionFixture
+    {
+        IConfigHolder::SP holder;
+        ConfigSubscription sub;
+        SourceFixture src;
+        SubscriptionFixture(const ConfigKey & key)
+            : holder(new ConfigHolder()),
+              sub(0, key, holder, Source::UP(new MySource(&src)))
+        {
+        }
+    };
+}
+
+TEST_FF("requireThatKeyIsReturned", ConfigKey("foo", "bar", "bim", "boo"), SubscriptionFixture(f1))
+{
+    ASSERT_TRUE(f1 == f2.sub.getKey());
+}
+
+TEST_F("requireThatUpdateReturns", SubscriptionFixture(ConfigKey::create<MyConfig>("myid")))
+{
+    f1.holder->handle(ConfigUpdate::UP(new ConfigUpdate(ConfigValue(), 1, 1)));
+    ASSERT_TRUE(f1.sub.nextUpdate(0, 0));
+    ASSERT_TRUE(f1.sub.hasChanged());
+    ASSERT_EQUAL(1, f1.sub.getGeneration());
+}
+
+TEST_F("requireThatNextUpdateBlocks", SubscriptionFixture(ConfigKey::create<MyConfig>("myid")))
+{
+    ASSERT_FALSE(f1.sub.nextUpdate(0, 0));
+    f1.holder->handle(ConfigUpdate::UP(new ConfigUpdate(ConfigValue(), 1, 1)));
+    FastOS_Time timer;
+    timer.SetNow();
+    ASSERT_FALSE(f1.sub.nextUpdate(1, 500));
+    ASSERT_TRUE(timer.MilliSecsToNow() > 400.0);
+}
+
+TEST_MT_F("requireThatNextUpdateReturnsWhenNotified", 2, SubscriptionFixture(ConfigKey::create<MyConfig>("myid")))
+{
+    if (thread_id == 0) {
+        FastOS_Time timer;
+        timer.SetNow();
+        f1.holder->handle(ConfigUpdate::UP(new ConfigUpdate(ConfigValue(), 1, 1)));
+        ASSERT_TRUE(f1.sub.nextUpdate(2, 5000));
+        ASSERT_TRUE(timer.MilliSecsToNow() > 200.0);
+    } else {
+        FastOS_Thread::Sleep(500);
+        f1.holder->handle(ConfigUpdate::UP(new ConfigUpdate(ConfigValue(), 1, 1)));
+    }
+}
+
+
+TEST_MT_F("requireThatNextUpdateReturnsInterrupted", 2, SubscriptionFixture(ConfigKey::create<MyConfig>("myid")))
+{
+    if (thread_id == 0) {
+        FastOS_Time timer;
+        timer.SetNow();
+        f1.holder->handle(ConfigUpdate::UP(new ConfigUpdate(ConfigValue(), 1, 1)));
+        ASSERT_TRUE(f1.sub.nextUpdate(1, 5000));
+        ASSERT_TRUE(timer.MilliSecsToNow() > 300.0);
+    } else {
+        FastOS_Thread::Sleep(500);
+        f1.sub.close();
+    }
+}
+
+TEST_F("Require that isChanged takes generation into account", SubscriptionFixture(ConfigKey::create<MyConfig>("myid")))
+{
+    f1.holder->handle(ConfigUpdate::UP(new ConfigUpdate(ConfigValue(), true, 1)));
+    ASSERT_TRUE(f1.sub.nextUpdate(0, 0));
+    f1.sub.flip();
+    ASSERT_EQUAL(1, f1.sub.getLastGenerationChanged());
+    f1.holder->handle(ConfigUpdate::UP(new ConfigUpdate(ConfigValue(), true, 2)));
+    ASSERT_TRUE(f1.sub.nextUpdate(1, 0));
+    f1.sub.flip();
+    ASSERT_EQUAL(2, f1.sub.getLastGenerationChanged());
+    f1.holder->handle(ConfigUpdate::UP(new ConfigUpdate(ConfigValue(), false, 3)));
+    ASSERT_TRUE(f1.sub.nextUpdate(2, 0));
+    f1.sub.flip();
+    ASSERT_EQUAL(2, f1.sub.getLastGenerationChanged());
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/trace/.gitignore b/config/src/tests/trace/.gitignore
new file mode 100644
index 00000000000..d87470776bf
--- /dev/null
+++ b/config/src/tests/trace/.gitignore
@@ -0,0 +1 @@
+config_trace_test_app
diff --git a/config/src/tests/trace/CMakeLists.txt b/config/src/tests/trace/CMakeLists.txt
new file mode 100644
index 00000000000..b328f61abdc
--- /dev/null
+++ b/config/src/tests/trace/CMakeLists.txt
@@ -0,0 +1,8 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_trace_test_app
+    SOURCES
+    trace.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_trace_test_app COMMAND config_trace_test_app)
diff --git a/config/src/tests/trace/trace.cpp b/config/src/tests/trace/trace.cpp
new file mode 100644
index 00000000000..9945acae485
--- /dev/null
+++ b/config/src/tests/trace/trace.cpp
@@ -0,0 +1,70 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP("frt");
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/common/trace.h>
+#include <vespa/vespalib/trace/tracenode.h>
+
+
+using namespace config;
+using namespace vespalib;
+using namespace vespalib::slime;
+
+struct FixedClock : public Clock
+{
+    FixedClock() : currentTime(0) { }
+    int64_t currentTime;
+    int64_t currentTimeMillis() const { return currentTime; }
+};
+
+TEST("that trace can be serialized and deserialized") {
+    Trace trace(4);
+    trace.trace(4, "foo");
+    trace.trace(3, "bar");
+    trace.trace(5, "baz");
+
+    Slime slime;
+    Cursor & cursor(slime.setObject());
+    trace.serialize(cursor);
+
+    Trace trace2;
+    trace2.deserialize(slime.get());
+
+    Slime slime2;
+    trace2.serialize(slime2.setObject());
+    Trace trace3;
+    trace3.deserialize(slime2.get());
+
+    EXPECT_EQUAL(trace.toString(), trace3.toString());
+}
+
+TEST_F("that trace level is taken into account", FixedClock) {
+    f1.currentTime = 3;
+    Trace trace(4, f1);
+    trace.trace(4, "foo");
+    trace.trace(5, "bar");
+    EXPECT_EQUAL("[\n"
+"    {\n"
+"        \"timestamp\": 3,\n"
+"        \"payload\": \"foo\"\n"
+"    }\n"
+"]\n", trace.toString());
+}
+
+TEST("that trace can be copied") {
+    Trace trace(3);
+    trace.trace(2, "foo");
+    trace.trace(3, "bar");
+    Trace trace2(trace);
+    EXPECT_EQUAL(trace.toString(), trace2.toString());
+}
+
+TEST("ensure that system clock is used by default") {
+    Trace trace(2);
+    trace.trace(1, "foo");
+    TraceNode child(trace.getRoot().getChild(0));
+    EXPECT_TRUE(child.getTimestamp() > 0);
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/tests/unittest/.gitignore b/config/src/tests/unittest/.gitignore
new file mode 100644
index 00000000000..d44770410b1
--- /dev/null
+++ b/config/src/tests/unittest/.gitignore
@@ -0,0 +1,7 @@
+/config-bar.cpp
+/config-bar.h
+/config-foo.cpp
+/config-foo.h
+/config-my.cpp
+/config-my.h
+config_unittest_test_app
diff --git a/config/src/tests/unittest/CMakeLists.txt b/config/src/tests/unittest/CMakeLists.txt
new file mode 100644
index 00000000000..9eeb5c761d1
--- /dev/null
+++ b/config/src/tests/unittest/CMakeLists.txt
@@ -0,0 +1,11 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_executable(config_unittest_test_app
+    SOURCES
+    unittest.cpp
+    DEPENDS
+    config_cloudconfig
+)
+vespa_add_test(NAME config_unittest_test_app COMMAND config_unittest_test_app)
+vespa_generate_config(config_unittest_test_app ../../test/resources/configdefinitions/my.def)
+vespa_generate_config(config_unittest_test_app ../../test/resources/configdefinitions/foo.def)
+vespa_generate_config(config_unittest_test_app ../../test/resources/configdefinitions/bar.def)
diff --git a/config/src/tests/unittest/unittest.cpp b/config/src/tests/unittest/unittest.cpp
new file mode 100644
index 00000000000..ca83dfee486
--- /dev/null
+++ b/config/src/tests/unittest/unittest.cpp
@@ -0,0 +1,94 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP("unittest");
+#include <vespa/vespalib/testkit/test_kit.h>
+#include <vespa/config/config.h>
+#include "config-my.h"
+#include "config-foo.h"
+#include "config-bar.h"
+
+using namespace config;
+
+namespace {
+    void verifyConfig(const std::string & expected, std::unique_ptr<FooConfig> cfg)
+    {
+        ASSERT_TRUE(cfg.get() != NULL);
+        ASSERT_EQUAL(expected, cfg->fooValue);
+    }
+
+    void verifyConfig(const std::string & expected, std::unique_ptr<BarConfig> cfg)
+    {
+        ASSERT_TRUE(cfg.get() != NULL);
+        ASSERT_EQUAL(expected, cfg->barValue);
+    }
+}
+#if 0
+TEST("requireThatUnitTestsCanBeCreated") {
+    MyConfigBuilder builder;
+    builder.myField = "myval";
+    ConfigSet set;
+    set.addBuilder("myid", &builder);
+    std::unique_ptr<MyConfig> cfg = ConfigGetter<MyConfig>::getConfig("myid", set);
+}
+#endif
+
+TEST("requireThatConfigCanBeReloaded") {
+    ConfigSet set;
+    ConfigContext::SP ctx(new ConfigContext(set));
+    MyConfigBuilder builder;
+    builder.myField = "myfoo";
+    set.addBuilder("myid", &builder);
+    ConfigSubscriber subscriber(ctx);
+
+    ConfigHandle<MyConfig>::UP handle = subscriber.subscribe<MyConfig>("myid");
+    ASSERT_TRUE(subscriber.nextConfig(0));
+    std::unique_ptr<MyConfig> cfg(handle->getConfig());
+    ASSERT_TRUE(cfg.get() != NULL);
+    ASSERT_EQUAL("myfoo", cfg->myField);
+    ctx->reload();
+    ASSERT_FALSE(subscriber.nextConfig(1000));
+    builder.myField = "foobar";
+    ctx->reload();
+    ASSERT_TRUE(subscriber.nextConfig(10000));
+    cfg = handle->getConfig();
+    ASSERT_TRUE(cfg.get() != NULL);
+    ASSERT_EQUAL("foobar", cfg->myField);
+}
+
+TEST("requireThatCanSubscribeWithSameIdToDifferentDefs") {
+    ConfigSet set;
+    ConfigContext::SP ctx(new ConfigContext(set));
+    FooConfigBuilder fooBuilder;
+    BarConfigBuilder barBuilder;
+
+    fooBuilder.fooValue = "myfoo";
+    barBuilder.barValue = "mybar";
+
+    set.addBuilder("fooid", &fooBuilder);
+    set.addBuilder("fooid", &barBuilder);
+
+    ConfigSubscriber subscriber(ctx);
+    ConfigHandle<FooConfig>::UP h1 = subscriber.subscribe<FooConfig>("fooid");
+    ConfigHandle<BarConfig>::UP h2 = subscriber.subscribe<BarConfig>("fooid");
+
+    ASSERT_TRUE(subscriber.nextConfig(0));
+    verifyConfig("myfoo", h1->getConfig());
+    verifyConfig("mybar", h2->getConfig());
+    ctx->reload();
+    ASSERT_FALSE(subscriber.nextConfig(100));
+
+    fooBuilder.fooValue = "blabla";
+    ctx->reload();
+    ASSERT_TRUE(subscriber.nextConfig(5000));
+    verifyConfig("blabla", h1->getConfig());
+    verifyConfig("mybar", h2->getConfig());
+
+    barBuilder.barValue = "blabar";
+    ctx->reload();
+    ASSERT_TRUE(subscriber.nextConfig(5000));
+    verifyConfig("blabla", h1->getConfig());
+    verifyConfig("blabar", h2->getConfig());
+}
+
+TEST_MAIN() { TEST_RUN_ALL(); }
diff --git a/config/src/vespa/config/.gitignore b/config/src/vespa/config/.gitignore
new file mode 100644
index 00000000000..929512da880
--- /dev/null
+++ b/config/src/vespa/config/.gitignore
@@ -0,0 +1,4 @@
+/.depend
+/Makefile
+/libconfig.so.5.1
+/libcloudconfig.so.5.1
diff --git a/config/src/vespa/config/CMakeLists.txt b/config/src/vespa/config/CMakeLists.txt
new file mode 100644
index 00000000000..6781d09aef1
--- /dev/null
+++ b/config/src/vespa/config/CMakeLists.txt
@@ -0,0 +1,16 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_library(config_cloudconfig
+    SOURCES
+    $<TARGET_OBJECTS:config_common>
+    $<TARGET_OBJECTS:config_subscription>
+    $<TARGET_OBJECTS:config_configgen>
+    $<TARGET_OBJECTS:config_raw>
+    $<TARGET_OBJECTS:config_file>
+    $<TARGET_OBJECTS:config_frt>
+    $<TARGET_OBJECTS:config_helper>
+    $<TARGET_OBJECTS:config_print>
+    $<TARGET_OBJECTS:config_set>
+    $<TARGET_OBJECTS:config_retriever>
+    INSTALL lib64
+    DEPENDS
+)
diff --git a/config/src/vespa/config/common/.gitignore b/config/src/vespa/config/common/.gitignore
new file mode 100644
index 00000000000..cd4bc99c04f
--- /dev/null
+++ b/config/src/vespa/config/common/.gitignore
@@ -0,0 +1,2 @@
+/Makefile
+/.depend
diff --git a/config/src/vespa/config/common/CMakeLists.txt b/config/src/vespa/config/common/CMakeLists.txt
new file mode 100644
index 00000000000..81a81456906
--- /dev/null
+++ b/config/src/vespa/config/common/CMakeLists.txt
@@ -0,0 +1,21 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_library(config_common OBJECT
+    SOURCES
+    configmanager.cpp
+    misc.cpp
+    configparser.cpp
+    errorcode.cpp
+    timingvalues.cpp
+    configupdate.cpp
+    configholder.cpp
+    configcontext.cpp
+    configkey.cpp
+    configvalue.cpp
+    trace.cpp
+    payload_converter.cpp
+    configdefinition.cpp
+    compressiontype.cpp
+    vespa_version.cpp
+    exceptions.cpp
+    DEPENDS
+)
diff --git a/config/src/vespa/config/common/cancelhandler.h b/config/src/vespa/config/common/cancelhandler.h
new file mode 100644
index 00000000000..10bdd9d7775
--- /dev/null
+++ b/config/src/vespa/config/common/cancelhandler.h
@@ -0,0 +1,22 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+namespace config {
+
+class ConfigSubscription;
+
+struct CancelHandler
+{
+    /**
+     * Cancels this subscription. Once this operation is done, the handler
+     * should have no knowledge of the subscription representing this id.
+     *
+     * @param subscription ConfigSubscription to cancel
+     */
+    virtual void unsubscribe(const ConfigSubscription::SP & subscription) = 0;
+
+    virtual ~CancelHandler() { }
+};
+
+}
+
diff --git a/config/src/vespa/config/common/compressiontype.cpp b/config/src/vespa/config/common/compressiontype.cpp
new file mode 100644
index 00000000000..5ee8d75b631
--- /dev/null
+++ b/config/src/vespa/config/common/compressiontype.cpp
@@ -0,0 +1,27 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include "compressiontype.h"
+
+namespace config {
+
+vespalib::string
+compressionTypeToString(const CompressionType & compressionType)
+{
+    switch (compressionType) {
+        case CompressionType::UNCOMPRESSED:
+            return "UNCOMPRESSED";
+        default:
+            return "LZ4";
+    }
+}
+
+CompressionType
+stringToCompressionType(const vespalib::string & type)
+{
+    if (type.compare("UNCOMPRESSED") == 0) {
+        return CompressionType::UNCOMPRESSED;
+    } else {
+        return CompressionType::LZ4;
+    }
+}
+
+}
diff --git a/config/src/vespa/config/common/compressiontype.h b/config/src/vespa/config/common/compressiontype.h
new file mode 100644
index 00000000000..d923c9c5e07
--- /dev/null
+++ b/config/src/vespa/config/common/compressiontype.h
@@ -0,0 +1,13 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+
+namespace config {
+
+enum class CompressionType {UNCOMPRESSED, LZ4};
+vespalib::string compressionTypeToString(const CompressionType & compressionType);
+CompressionType stringToCompressionType(const vespalib::string & type);
+
+}
+
diff --git a/config/src/vespa/config/common/configcontext.cpp b/config/src/vespa/config/common/configcontext.cpp
new file mode 100644
index 00000000000..d770c5f1371
--- /dev/null
+++ b/config/src/vespa/config/common/configcontext.cpp
@@ -0,0 +1,39 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.common.configcontext");
+#include "configcontext.h"
+#include "configmanager.h"
+#include "exceptions.h"
+
+namespace config {
+
+ConfigContext::ConfigContext(const SourceSpec & spec)
+    : _timingValues(),
+      _generation(1),
+      _manager(spec.createSourceFactory(_timingValues), _generation)
+{
+}
+
+ConfigContext::ConfigContext(const TimingValues & timingValues, const SourceSpec & spec)
+    : _timingValues(timingValues),
+      _generation(1),
+      _manager(spec.createSourceFactory(_timingValues), _generation)
+{
+}
+
+IConfigManager &
+ConfigContext::getManagerInstance()
+{
+    return _manager;
+}
+
+void
+ConfigContext::reload()
+{
+    _generation++;
+    _manager.reload(_generation);
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/common/configcontext.h b/config/src/vespa/config/common/configcontext.h
new file mode 100644
index 00000000000..6ada928fd5f
--- /dev/null
+++ b/config/src/vespa/config/common/configcontext.h
@@ -0,0 +1,53 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/util/sync.h>
+#include <vespa/vespalib/stllike/hash_map.h>
+#include "timingvalues.h"
+#include "configmanager.h"
+#include <vespa/config/subscription/sourcespec.h>
+
+namespace config {
+
+/**
+ * A ConfigContext is a context object that can be used to consolidate
+ * multiple ConfigSubscribers to use the same resources. It also gives the
+ * ability to reload config for unit testing or if using file configs.
+ */
+class IConfigContext
+{
+public:
+    typedef std::shared_ptr<IConfigContext> SP;
+
+    /**
+     * Get an instance of the config manager.
+     *
+     * @return reference to a manager instance.
+     */
+    virtual IConfigManager & getManagerInstance() = 0;
+
+    /**
+     * Reload config for source provided by this context.
+     */
+    virtual void reload() = 0;
+
+    virtual ~IConfigContext() { }
+};
+
+class ConfigContext : public IConfigContext
+{
+public:
+    ConfigContext(const SourceSpec & spec = ServerSpec());
+    ConfigContext(const TimingValues & timingValues, const SourceSpec & spec = ServerSpec());
+    IConfigManager & getManagerInstance();
+    void reload();
+
+private:
+    TimingValues _timingValues;
+    int64_t _generation;
+    ConfigManager _manager;
+};
+
+
+} // namespace
+
diff --git a/config/src/vespa/config/common/configdefinition.cpp b/config/src/vespa/config/common/configdefinition.cpp
new file mode 100644
index 00000000000..4784a86ede9
--- /dev/null
+++ b/config/src/vespa/config/common/configdefinition.cpp
@@ -0,0 +1,45 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include "configdefinition.h"
+#include <vespa/vespalib/stllike/asciistream.h>
+
+using namespace vespalib;
+using namespace vespalib::slime;
+
+namespace config {
+
+ConfigDefinition::ConfigDefinition()
+    : _schema()
+{}
+
+ConfigDefinition::ConfigDefinition(const std::vector<vespalib::string> & schema)
+    : _schema(schema)
+{}
+
+void
+ConfigDefinition::serialize(Cursor & cursor) const
+{
+    for (auto it(_schema.begin()), mt(_schema.end()); it != mt; it++) {
+        cursor.addString(Memory(*it));
+    }
+}
+
+void
+ConfigDefinition::deserialize(const Inspector & inspector)
+{
+    for (size_t i(0); i < inspector.entries(); i++) {
+        _schema.push_back(inspector[i].asString().make_string());
+    }
+}
+
+vespalib::string
+ConfigDefinition::asString() const
+{
+    vespalib::asciistream as;
+    for (auto it(_schema.begin()), mt(_schema.end()); it != mt; it++) {
+        as << *it;
+    }
+    return as.str();
+}
+
+}
+
diff --git a/config/src/vespa/config/common/configdefinition.h b/config/src/vespa/config/common/configdefinition.h
new file mode 100644
index 00000000000..3c043eb6720
--- /dev/null
+++ b/config/src/vespa/config/common/configdefinition.h
@@ -0,0 +1,25 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+#include <vector>
+#include <vespa/vespalib/data/slime/slime.h>
+
+namespace config {
+
+/**
+ * Represents a config definition.
+ */
+class ConfigDefinition {
+public:
+    ConfigDefinition();
+    ConfigDefinition(const std::vector<vespalib::string> & schema);
+    void deserialize(const vespalib::slime::Inspector & inspector);
+    void serialize(vespalib::slime::Cursor & cursor) const;
+    vespalib::string asString() const;
+private:
+    std::vector<vespalib::string> _schema;
+};
+
+} //namespace config
+
diff --git a/config/src/vespa/config/common/configholder.cpp b/config/src/vespa/config/common/configholder.cpp
new file mode 100644
index 00000000000..1b0d1e0d16b
--- /dev/null
+++ b/config/src/vespa/config/common/configholder.cpp
@@ -0,0 +1,50 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "configholder.h"
+
+namespace config {
+
+ConfigHolder::ConfigHolder()
+    : _monitor(),
+      _current()
+{
+}
+
+ConfigUpdate::UP
+ConfigHolder::provide()
+{
+    vespalib::MonitorGuard guard(_monitor);
+    ConfigUpdate::UP ret(new ConfigUpdate(*_current));
+    return ret;
+}
+
+void
+ConfigHolder::handle(ConfigUpdate::UP update)
+{
+    vespalib::MonitorGuard guard(_monitor);
+    _current = std::move(update);
+    guard.broadcast();
+}
+
+bool
+ConfigHolder::wait(uint64_t timeoutInMillis)
+{
+    vespalib::MonitorGuard guard(_monitor);
+    return guard.wait(timeoutInMillis);
+}
+
+bool
+ConfigHolder::poll()
+{
+    vespalib::MonitorGuard guard(_monitor);
+    return (_current.get() != NULL);
+}
+
+void
+ConfigHolder::interrupt()
+{
+    vespalib::MonitorGuard guard(_monitor);
+    guard.broadcast();
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/common/configholder.h b/config/src/vespa/config/common/configholder.h
new file mode 100644
index 00000000000..abcc9c059cd
--- /dev/null
+++ b/config/src/vespa/config/common/configholder.h
@@ -0,0 +1,28 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "iconfigholder.h"
+#include <vespa/vespalib/util/sync.h>
+
+namespace config {
+
+/**
+ * A config holder contains the latest config object of a subscription.
+ */
+class ConfigHolder : public IConfigHolder
+{
+public:
+    ConfigHolder();
+
+    ConfigUpdate::UP provide();
+    void handle(ConfigUpdate::UP update);
+    bool wait(uint64_t timeoutInMillis);
+    bool poll();
+    void interrupt();
+public:
+    vespalib::Monitor _monitor;
+    ConfigUpdate::UP _current;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/common/configkey.cpp b/config/src/vespa/config/common/configkey.cpp
new file mode 100644
index 00000000000..c22042418c0
--- /dev/null
+++ b/config/src/vespa/config/common/configkey.cpp
@@ -0,0 +1,79 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "configkey.h"
+
+namespace config {
+
+ConfigKey::ConfigKey(const vespalib::stringref & configId,
+                     const vespalib::stringref & defName,
+                     const vespalib::stringref & defNamespace,
+                     const vespalib::stringref & defMd5)
+    : _configId(configId),
+      _defName(defName),
+      _defNamespace(defNamespace),
+      _defMd5(defMd5),
+      _defSchema(),
+      _key(_configId + _defName + _defNamespace)
+{}
+
+ConfigKey::ConfigKey(const vespalib::stringref & configId,
+                     const vespalib::stringref & defName,
+                     const vespalib::stringref & defNamespace,
+                     const vespalib::stringref & defMd5,
+                     const std::vector<vespalib::string> & defSchema)
+    : _configId(configId),
+      _defName(defName),
+      _defNamespace(defNamespace),
+      _defMd5(defMd5),
+      _defSchema(defSchema),
+      _key(_configId + _defName + _defNamespace)
+{
+}
+
+ConfigKey::ConfigKey()
+    : _configId(),
+      _defName(),
+      _defNamespace(),
+      _defMd5(),
+      _defSchema(),
+      _key()
+{}
+
+bool
+ConfigKey::operator<(const ConfigKey & rhs) const
+{
+    return _key < rhs._key;
+}
+
+bool
+ConfigKey::operator>(const ConfigKey & rhs) const
+{
+    return _key > rhs._key;
+}
+
+bool
+ConfigKey::operator==(const ConfigKey & rhs) const
+{
+    return _key.compare(rhs._key) == 0;
+}
+
+const vespalib::string & ConfigKey::getDefName() const { return _defName; }
+const vespalib::string & ConfigKey::getConfigId() const { return _configId; }
+const vespalib::string & ConfigKey::getDefNamespace() const { return _defNamespace; }
+const vespalib::string & ConfigKey::getDefMd5() const { return _defMd5; }
+const std::vector<vespalib::string> & ConfigKey::getDefSchema() const { return _defSchema; }
+
+const vespalib::string
+ConfigKey::toString() const
+{
+    vespalib::string s;
+    s.append("name=");
+    s.append(_defName);
+    s.append(",namespace=");
+    s.append(_defNamespace);
+    s.append(",configId=");
+    s.append(_configId);
+    return s;
+}
+
+}
diff --git a/config/src/vespa/config/common/configkey.h b/config/src/vespa/config/common/configkey.h
new file mode 100644
index 00000000000..f6938a4fa1b
--- /dev/null
+++ b/config/src/vespa/config/common/configkey.h
@@ -0,0 +1,54 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+#include <vector>
+
+namespace config {
+
+class ConfigKey {
+public:
+    ConfigKey(const vespalib::stringref & configId,
+              const vespalib::stringref & defName,
+              const vespalib::stringref & defNamespace,
+              const vespalib::stringref & defMd5);
+
+    ConfigKey(const vespalib::stringref & configId,
+              const vespalib::stringref & defName,
+              const vespalib::stringref & defNamespace,
+              const vespalib::stringref & defMd5,
+              const std::vector<vespalib::string> & defSchema);
+
+    ConfigKey();
+
+    bool operator<(const ConfigKey & rhs) const;
+    bool operator>(const ConfigKey & rhs) const;
+    bool operator==(const ConfigKey & rhs) const;
+
+    const vespalib::string & getDefName() const;
+    const vespalib::string & getConfigId() const;
+    const vespalib::string & getDefNamespace() const;
+    const vespalib::string & getDefMd5() const;
+    const std::vector<vespalib::string> & getDefSchema() const;
+
+    template <typename ConfigType>
+    static const ConfigKey create(const vespalib::stringref & configId)
+    {
+        return ConfigKey(configId, ConfigType::CONFIG_DEF_NAME,
+                                   ConfigType::CONFIG_DEF_NAMESPACE,
+                                   ConfigType::CONFIG_DEF_MD5,
+                                   ConfigType::CONFIG_DEF_SCHEMA);
+    }
+
+    const vespalib::string toString() const;
+private:
+    vespalib::string _configId;
+    vespalib::string _defName;
+    vespalib::string _defNamespace;
+    vespalib::string _defMd5;
+    std::vector<vespalib::string> _defSchema;
+    vespalib::string _key;
+};
+
+} //namespace config
+
diff --git a/config/src/vespa/config/common/configmanager.cpp b/config/src/vespa/config/common/configmanager.cpp
new file mode 100644
index 00000000000..e510079239f
--- /dev/null
+++ b/config/src/vespa/config/common/configmanager.cpp
@@ -0,0 +1,76 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.common.configmanager");
+#include "configmanager.h"
+#include "exceptions.h"
+#include "configholder.h"
+#include <vespa/vespalib/util/exception.h>
+#include <vespa/vespalib/util/atomic.h>
+#include <memory>
+
+namespace config {
+
+ConfigManager::ConfigManager(SourceFactory::UP sourceFactory, int64_t initialGeneration)
+    : _idGenerator(0),
+      _sourceFactory(std::move(sourceFactory)),
+      _generation(initialGeneration),
+      _subscriptionMap(),
+      _lock(),
+      _firstLock(),
+      _first(true)
+{
+}
+
+ConfigSubscription::SP
+ConfigManager::subscribe(const ConfigKey & key, uint64_t timeoutInMillis)
+{
+    LOG(debug, "subscribing on def %s, configid %s", key.getDefName().c_str(), key.getConfigId().c_str());
+
+    SubscriptionId id(vespalib::Atomic::postInc(&_idGenerator));
+
+    IConfigHolder::SP holder(new ConfigHolder());
+    Source::UP source = _sourceFactory->createSource(holder, key);
+    source->reload(_generation);
+
+    source->getConfig();
+    ConfigSubscription::SP subscription(new ConfigSubscription(id, key, holder, std::move(source)));
+
+    FastOS_Time timer;
+    timer.SetNow();
+    while (timer.MilliSecsToNow() < timeoutInMillis) {
+        if (holder->poll())
+            break;
+        FastOS_Thread::Sleep(10);
+    }
+    if (!holder->poll()) {
+        std::ostringstream oss;
+        oss << "Timed out while subscribing to '" << key.getDefNamespace() << "." << key.getDefName() << "', configid '" << key.getConfigId() << "'";
+        throw ConfigTimeoutException(oss.str());
+    }
+    LOG(debug, "done subscribing");
+    vespalib::LockGuard guard(_lock);
+    _subscriptionMap[id] = subscription;
+    return subscription;
+}
+
+void
+ConfigManager::unsubscribe(const ConfigSubscription::SP & subscription)
+{
+    vespalib::LockGuard guard(_lock);
+    const SubscriptionId id(subscription->getSubscriptionId());
+    if (_subscriptionMap.find(id) != _subscriptionMap.end())
+        _subscriptionMap.erase(id);
+}
+
+void
+ConfigManager::reload(int64_t generation)
+{
+    _generation = generation;
+    vespalib::LockGuard guard(_lock);
+    for (SubscriptionMap::iterator it(_subscriptionMap.begin()), mt(_subscriptionMap.end()); it != mt; it++) {
+        it->second->reload(_generation);
+    }
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/common/configmanager.h b/config/src/vespa/config/common/configmanager.h
new file mode 100644
index 00000000000..2c3d5cbe297
--- /dev/null
+++ b/config/src/vespa/config/common/configmanager.h
@@ -0,0 +1,48 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/subscription/configsubscription.h>
+#include "iconfigmanager.h"
+#include "sourcefactory.h"
+#include <vespa/vespalib/util/sync.h>
+#include <map>
+
+namespace config {
+
+class SourceSpec;
+struct TimingValues;
+
+/**
+ * An instance of this class represents a manager for config subscriptions, that use a common Source.
+ * Getting and/or creating a new instance is done by calling the factory method getInstance(Source).
+ *
+ * The manager holds a reference to each subscription.
+ */
+class ConfigManager : public IConfigManager
+{
+public:
+    ConfigManager(SourceFactory::UP sourceFactory, int64_t initialGeneration);
+
+    // Implements IConfigManager
+    ConfigSubscription::SP subscribe(const ConfigKey & key, uint64_t timeoutInMillis);
+
+    // Implements IConfigManager
+    void unsubscribe(const ConfigSubscription::SP & subscription);
+
+    // Implements IConfigManager
+    void reload(int64_t generation);
+
+private:
+    SubscriptionId _idGenerator;
+    SourceFactory::UP _sourceFactory;
+    int64_t _generation;
+
+    typedef std::map<SubscriptionId, ConfigSubscription::SP> SubscriptionMap;
+    SubscriptionMap _subscriptionMap;
+    vespalib::Lock _lock;
+    vespalib::Lock _firstLock;
+    bool _first;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/common/configparser.cpp b/config/src/vespa/config/common/configparser.cpp
new file mode 100644
index 00000000000..67237ef9fdc
--- /dev/null
+++ b/config/src/vespa/config/common/configparser.cpp
@@ -0,0 +1,374 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/config/common/configparser.h>
+#include <vespa/vespalib/stllike/string.h>
+#include <vespa/vespalib/stllike/asciistream.h>
+#include <stdio.h>
+#include "misc.h"
+
+namespace config {
+
+vespalib::string
+ConfigParser::deQuote(const vespalib::stringref & source)
+{
+    const char *src = source.c_str();
+    const char *s = src;
+    std::vector<char> dst(1+source.length());
+    char *d = &dst[0];
+    bool isQuoted;
+
+    if (*s == '"') {
+        isQuoted = true;
+        ++s;
+    } else {
+        isQuoted = false;
+    }
+
+    while (1) {
+        const char hexchars[] = "0123456789abcdefABCDEF";
+
+        char c = *s++;
+        if (isQuoted && c == '\\') { // Escape char only allowed in quotes
+            char escaped = *s++;
+            switch (escaped) {
+            case 'n':
+                *d++ = '\n';
+                break;
+            case 'r':
+                *d++ = '\r';
+                break;
+            case '\\':
+                *d++ = '\\';
+                break;
+            case '"':
+                *d++ = '"';
+                break;
+            case 'x':
+                // XXX we should have a utility routine for this
+                if (strchr(hexchars, s[0]) && strchr(hexchars, s[1])) {
+                    unsigned int hex = 0;
+                    sscanf(s, "%2x", &hex);
+                    s += 2;
+                    *d++ = hex;
+                } else {
+                    throwInvalid("Invalid \\x escape \\x%.2s in %s", s, src);
+                }
+                break;
+            default:
+                throwInvalid("Invalid escape character in %s: \\%c", src, escaped);
+                break;
+            }
+        } else if (!c) {
+            if (isQuoted) {
+                throwInvalid("Unterminated quotes in (len=%u) '%s'", (uint32_t)strlen(src), src);
+            }
+            break;
+        } else if (c == '"') {
+            if (!isQuoted) {
+                throwInvalid("Quote character inside unquoted string in '%s'", src);
+            }
+            if (*s) throwInvalid("string must terminate after quotes: '%s'", src);
+            break;
+        } else {
+            *d++ = c;
+        }
+    }
+    *d = 0;
+    return vespalib::string(&dst[0], d - &dst[0]);
+}
+
+namespace {
+
+bool
+getValueForKey(const vespalib::stringref & key, const vespalib::stringref & line,
+               vespalib::string& retval)
+{
+    if (line.length() <= key.length()) {
+        return false;
+    }
+
+    vespalib::stringref sub = line.substr(0, key.length());
+    if (sub != key) {
+        return false;
+    }
+
+    int pos = key.length();
+
+    if (line[pos] == ' ' || line[pos] == '.') {
+        retval = line.substr(pos + 1);
+        return true;
+    }
+    if (line[pos] == '[') {
+        retval = line.substr(pos);
+        // We don't need array declarations
+        if (retval[retval.size() - 1] == ']')
+            return false;
+        return true;
+    }
+    if (line[pos] == '{') {
+        retval = line.substr(pos);
+        // Skip empty maps
+        if (retval[retval.size() - 1] == '}')
+            return false;
+        return true;
+    }
+
+    return false;
+}
+
+}
+
+std::vector<vespalib::string>
+ConfigParser::getLinesForKey(const vespalib::stringref & key,
+                             const vsvector & lines)
+{
+    vsvector retval;
+
+    for (uint32_t i = 0; i < lines.size(); i++) {
+        vespalib::string value;
+
+        if (getValueForKey(key, lines[i], value)) {
+            retval.push_back(value);
+        }
+    }
+
+    return retval;
+}
+
+void
+ConfigParser::stripLinesForKey(const vespalib::stringref & key,
+                               std::set<vespalib::string>& config)
+{
+    vespalib::string value;
+    for (std::set<vespalib::string>::iterator it = config.begin(); it != config.end();) {
+        if (getValueForKey(key, *it, value)) {
+            std::set<vespalib::string>::iterator it2 = it++;
+            config.erase(it2);
+        } else {
+            ++it;
+        }
+    }
+}
+
+std::map<vespalib::string, ConfigParser::vsvector>
+ConfigParser::splitMap(const vsvector & config)
+{
+    std::map<vespalib::string, vsvector> items;
+
+    vespalib::string lastValue;
+
+    // First line contains item count, skip that.
+    for (uint32_t i = 0; i < config.size(); i++) {
+        size_t pos = config[i].find("}");
+
+        if (config[i].size() < 3 || config[i][0] != '{'
+            || pos == vespalib::string::npos)
+        {
+            throw InvalidConfigException(
+                    "Value '" + config[i] + "' is not a valid map "
+                    "specification.", VESPA_STRLOC);
+        }
+
+        vespalib::string key = deQuote(config[i].substr(1, pos - 1));
+        vespalib::string value = config[i].substr(pos + 1);
+
+        if (key != lastValue) {
+            items[key] = vsvector();
+            lastValue = key;
+        }
+
+        if (value[0] == '.') {
+            items[key].push_back(value.substr(1));
+        } else {
+            items[key].push_back(value);
+        }
+    }
+    return items;
+}
+
+std::vector<ConfigParser::vsvector>
+ConfigParser::splitArray(const vsvector & config)
+{
+    std::vector<vsvector> items;
+
+    vespalib::string lastValue;
+
+    // First line contains item count, skip that.
+    for (uint32_t i = 0; i < config.size(); i++) {
+        size_t pos = config[i].find("]");
+
+        if (config[i].size() < 3 || config[i][0] != '['
+            || pos == vespalib::string::npos)
+        {
+            throw InvalidConfigException(
+                    "Value '" + config[i] + "' is not a valid array "
+                    "specification.", VESPA_STRLOC);
+        }
+
+        vespalib::string key = config[i].substr(1, pos - 1);
+        vespalib::string value = config[i].substr(pos + 1);
+
+        if (key != lastValue) {
+            items.push_back(vsvector());
+            lastValue = key;
+        }
+
+        if (value[0] == '.') {
+            items.back().push_back(value.substr(1));
+        } else {
+            items.back().push_back(value);
+        }
+    }
+    return items;
+}
+
+vespalib::string
+ConfigParser::stripWhitespace(const vespalib::stringref & source)
+{
+    // Remove leading spaces and return.
+    if (source.empty()) {
+        return source;
+    }
+    size_t start = 0;
+    bool found = false;
+    while (!found && start < source.size()) {
+        switch (source[start]) {
+            case ' ':
+            case '\t':
+            case '\r':
+            case '\f':
+                ++start;
+                break;
+            default:
+                found = true;
+        }
+    }
+    size_t stop = source.size() - 1;
+    found = false;
+    while (!found && stop > start) {
+        switch (source[stop]) {
+            case ' ':
+            case '\t':
+            case '\r':
+            case '\f':
+                --stop;
+                break;
+            default:
+                found = true;
+        }
+    }
+    return source.substr(start, stop - start + 1);
+}
+
+vespalib::string
+ConfigParser::arrayToString(const vsvector & array)
+{
+    vespalib::asciistream ost;
+    if (array.size() == 0) {
+        ost << "No entries";
+    } else {
+        for (uint32_t i=0; i<array.size(); ++i) {
+            ost << array[i] << "\n";
+        }
+    }
+    return ost.str();
+}
+
+template<>
+bool
+ConfigParser::convert<bool>(const vsvector & config)
+{
+    if (config.size() != 1) {
+        throw InvalidConfigException("Expected single line with bool value, "
+                "got " + arrayToString(config), VESPA_STRLOC);
+    }
+    std::string value = stripWhitespace(deQuote(config[0]));
+
+    if (value == "true") {
+        return true;
+    } else if (value == "false") {
+        return false;
+    } else {
+        throw InvalidConfigException("Expected bool value, got " + value
+                + "instead", VESPA_STRLOC);
+    }
+}
+
+template<>
+int32_t
+ConfigParser::convert<int32_t>(const vsvector & config)
+{
+    if (config.size() != 1) {
+        throw InvalidConfigException("Expected single line with int32_t value, "
+                "got " + arrayToString(config), VESPA_STRLOC);
+    }
+    std::string value(deQuote(stripWhitespace(config[0])));
+
+    const char *startp = value.c_str();
+    char *endp;
+    errno = 0;
+    int32_t ret = strtol(startp, &endp, 0);
+    int err = errno;
+    if (err == ERANGE || err == EINVAL || (*endp != '\0'))
+        throw InvalidConfigException("Value " + value + " is not a legal int32_t.", VESPA_STRLOC);
+    return ret;
+}
+
+template<>
+int64_t
+ConfigParser::convert<int64_t>(const vsvector & config)
+{
+    if (config.size() != 1) {
+        throw InvalidConfigException("Expected single line with int64_t value, "
+                "got " + arrayToString(config), VESPA_STRLOC);
+    }
+    std::string value(deQuote(stripWhitespace(config[0])));
+
+    const char *startp = value.c_str();
+    char *endp;
+    errno = 0;
+    int64_t ret = strtoll(startp, &endp, 0);
+    int err = errno;
+    if (err == ERANGE || err == EINVAL || (*endp != '\0'))
+        throw InvalidConfigException("Value " + value + " is not a legal int64_t.", VESPA_STRLOC);
+    return ret;
+}
+
+template<>
+double
+ConfigParser::convert<double>(const vsvector & config)
+{
+    if (config.size() != 1) {
+        throw InvalidConfigException("Expected single line with double value, "
+                "got " + arrayToString(config), VESPA_STRLOC);
+    }
+    std::string value(deQuote(stripWhitespace(config[0])));
+
+    const char *startp = value.c_str();
+    char *endp;
+    errno = 0;
+    double ret = strtod(startp, &endp);
+    int err = errno;
+    if (err == ERANGE || (*endp != '\0'))
+        throw InvalidConfigException("Value " + value + " is not a legal double",
+                VESPA_STRLOC);
+    return ret;
+}
+
+template<>
+vespalib::string
+ConfigParser::convert<vespalib::string>(const vsvector & config)
+{
+    if (config.size() != 1) {
+        throw InvalidConfigException("Expected single line with string value, "
+                "got " + arrayToString(config), VESPA_STRLOC);
+    }
+
+    std::string value = stripWhitespace(config[0]);
+
+    return deQuote(value);
+}
+
+template bool ConfigParser::convert<bool>(const vsvector & config);
+
+} // config
diff --git a/config/src/vespa/config/common/configparser.h b/config/src/vespa/config/common/configparser.h
new file mode 100644
index 00000000000..3b1185a48fa
--- /dev/null
+++ b/config/src/vespa/config/common/configparser.h
@@ -0,0 +1,168 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/exceptions.h>
+#include <map>
+#include <set>
+#include <vector>
+#include <errno.h>
+#include <stdint.h>
+#include <vespa/vespalib/stllike/string.h>
+
+namespace config {
+
+/**
+ * To reduce the need for code in autogenerated config classes, these
+ * helper functions exist to help parsing.
+ */
+class ConfigParser {
+public:
+    typedef std::vector<vespalib::string> vsvector;
+private:
+    static vsvector getLinesForKey( const vespalib::stringref & key, const vsvector & config);
+
+    static std::vector<vsvector> splitArray( const vsvector & config);
+    static std::map<vespalib::string, vsvector> splitMap( const vsvector & config);
+
+    static vespalib::string deQuote(const vespalib::stringref & source);
+
+    template<typename T>
+    static T convert(const vsvector &);
+
+    static vespalib::string arrayToString(const vsvector &);
+
+    template<typename T, typename V>
+    static T parseInternal(const vespalib::stringref & key, const V & config);
+    template<typename T, typename V>
+    static T parseInternal(const vespalib::stringref & key, const V & config, T defaultValue);
+
+    template<typename T, typename V>
+    static std::vector<T> parseArrayInternal(const vespalib::stringref & key, const V & config);
+    template<typename T, typename V>
+    static std::map<vespalib::string, T> parseMapInternal(const vespalib::stringref & key, const V & config);
+    template<typename T, typename V>
+    static T parseStructInternal(const vespalib::stringref & key, const V & config);
+
+public:
+    static void stripLinesForKey(const vespalib::stringref & key,
+                                 std::set<vespalib::string>& config);
+    static vespalib::string stripWhitespace(const vespalib::stringref & source);
+
+    template<typename T>
+    static T parse(const vespalib::stringref & key, const vsvector & config) {
+        return parseInternal<T, vsvector>(key, config);
+    }
+    template<typename T>
+    static T parse(const vespalib::stringref & key, const vsvector & config, T defaultValue) {
+        return parseInternal(key, config, defaultValue);
+    }
+
+    template<typename T>
+    static std::vector<T> parseArray(const vespalib::stringref & key, const vsvector & config) {
+        return parseArrayInternal<T, vsvector>(key, config);
+    }
+
+    template<typename T>
+    static std::map<vespalib::string, T> parseMap(const vespalib::stringref & key, const vsvector & config) {
+        return parseMapInternal<T, vsvector>(key, config);
+    }
+
+    template<typename T>
+    static T parseStruct(const vespalib::stringref & key, const vsvector & config) {
+        return parseStructInternal<T, vsvector>(key, config);
+    }
+
+};
+
+template<typename T, typename V>
+T
+ConfigParser::parseInternal(const vespalib::stringref & key, const V & config)
+{
+    V lines = getLinesForKey(key, config);
+
+    if (lines.size() == 0) {
+        throw InvalidConfigException("Config parameter " + key + " has no "
+                "default value and is not specified in config", VESPA_STRLOC);
+    }
+    return convert<T>(lines);
+}
+
+template<typename T, typename V>
+T
+ConfigParser::parseInternal(const vespalib::stringref & key, const V & config, T defaultValue)
+{
+    V lines = getLinesForKey(key, config);
+
+    if (lines.size() == 0) {
+        return defaultValue;
+    }
+
+    return convert<T>(lines);
+}
+
+template<typename T>
+T
+ConfigParser::convert(const vsvector & lines) {
+    return T(lines);
+}
+
+template<typename T, typename V>
+std::map<vespalib::string, T>
+ConfigParser::parseMapInternal(const vespalib::stringref & key, const V & config)
+{
+    V lines = getLinesForKey(key, config);
+    typedef std::map<vespalib::string, V> SplittedMap;
+    SplittedMap s = splitMap(lines);
+    std::map<vespalib::string, T> retval;
+    for (typename SplittedMap::iterator it(s.begin()), mt(s.end()); it != mt; it++) {
+        retval[it->first] = convert<T>(it->second);
+    }
+    return retval;
+}
+
+template<typename T, typename V>
+std::vector<T>
+ConfigParser::parseArrayInternal(const vespalib::stringref & key, const V & config)
+{
+    V lines = getLinesForKey(key, config);
+    std::vector<V> split = splitArray(lines);
+
+    std::vector<T> retval;
+    for (uint32_t i = 0; i < split.size(); i++) {
+        retval.push_back(convert<T>(split[i]));
+    }
+
+    return retval;
+}
+
+template<typename T, typename V>
+T
+ConfigParser::parseStructInternal(const vespalib::stringref & key, const V & config)
+{
+    V lines = getLinesForKey(key, config);
+
+    return convert<T>(lines);
+}
+
+template<>
+bool
+ConfigParser::convert<bool>(const vsvector & config);
+
+template<>
+int32_t
+ConfigParser::convert<int32_t>(const vsvector & config);
+
+template<>
+int64_t
+ConfigParser::convert<int64_t>(const vsvector & config);
+
+template<>
+double
+ConfigParser::convert<double>(const vsvector & config);
+
+template<>
+vespalib::string
+ConfigParser::convert<vespalib::string>(const vsvector & config);
+
+} // config
+
diff --git a/config/src/vespa/config/common/configrequest.h b/config/src/vespa/config/common/configrequest.h
new file mode 100644
index 00000000000..94d9aa352a2
--- /dev/null
+++ b/config/src/vespa/config/common/configrequest.h
@@ -0,0 +1,45 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <memory>
+
+namespace vespalib {
+    template <typename T>
+    class LinkedPtr;
+}
+
+namespace config {
+
+class ConfigKey;
+struct ConfigState;
+
+/**
+ * Baseclass for config requests.
+ *
+ * @author <a href="gv@yahoo-inc.com">Gj&oslash;ran Voldengen</a>
+ * @version : $Id: configrequest.h 125304 2011-08-25 07:53:59Z lulf $
+ */
+
+class ConfigRequest {
+private:
+    ConfigRequest& operator=(const ConfigRequest&);
+
+public:
+    typedef vespalib::LinkedPtr<ConfigRequest> LP;
+    typedef std::unique_ptr<ConfigRequest> UP;
+
+    ConfigRequest() { }
+    virtual ~ConfigRequest() { }
+
+    virtual const ConfigKey & getKey() const = 0;
+
+    /** Abort a request. */
+    virtual bool abort() = 0;
+
+    virtual bool isAborted() const = 0;
+
+    virtual void setError(int errorCode) = 0;
+};
+
+}
+
diff --git a/config/src/vespa/config/common/configresponse.h b/config/src/vespa/config/common/configresponse.h
new file mode 100644
index 00000000000..20bc1464e16
--- /dev/null
+++ b/config/src/vespa/config/common/configresponse.h
@@ -0,0 +1,55 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+
+namespace config {
+
+class ConfigValue;
+class ConfigKey;
+class ConfigState;
+class Trace;
+
+/**
+ * Baseclass for config responses.
+ */
+class ConfigResponse {
+public:
+    typedef std::unique_ptr<ConfigResponse> UP;
+
+    virtual ~ConfigResponse() { }
+
+    virtual const ConfigKey & getKey() const = 0;
+    virtual const ConfigValue & getValue() const = 0;
+
+    virtual const ConfigState & getConfigState() const = 0;
+    virtual const Trace & getTrace() const = 0;
+
+    virtual bool hasValidResponse() const = 0;
+
+    /**
+     * Verifies that the returned response meets any criteria (decided by the implementation) to use the getters
+     * for return values. The result from this validation can be found without performing the validation
+     * again by calling {@link ConfigResponse#hasValidResponse()}.
+     *
+     * @return true if the returned response meets criteria to use the getters for return values.
+     */
+    virtual bool validateResponse() = 0;
+
+    /**
+     * Fills all data received in the response in order to be able to retrieve
+     * the config values. Should not be called before the response has been
+     * validated.
+     */
+    virtual void fill() = 0;
+
+    /** @return Error message if a request has failed, null otherwise. */
+    virtual vespalib::string errorMessage() const = 0;
+
+    virtual int errorCode() const = 0;
+
+    virtual bool isError() const = 0;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/common/configstate.h b/config/src/vespa/config/common/configstate.h
new file mode 100644
index 00000000000..39c206a8f83
--- /dev/null
+++ b/config/src/vespa/config/common/configstate.h
@@ -0,0 +1,36 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+#include "misc.h"
+
+namespace config {
+
+/**
+ * A config state represents the current state of a config instance
+ */
+struct ConfigState
+{
+public:
+    ConfigState()
+        : md5(""),
+          generation(0)
+    { }
+    ConfigState(const vespalib::string & md5sum, int64_t gen)
+        : md5(md5sum),
+          generation(gen)
+    { }
+
+    vespalib::string md5;
+    int64_t generation;
+
+    bool isNewerGenerationThan(const ConfigState & other) const {
+        return isGenerationNewer(generation, other.generation);
+    }
+
+    bool hasDifferentPayloadFrom(const ConfigState & other) const {
+        return (md5.compare(other.md5) != 0);
+    }
+};
+
+} // namespace config
diff --git a/config/src/vespa/config/common/configupdate.cpp b/config/src/vespa/config/common/configupdate.cpp
new file mode 100644
index 00000000000..87064f4e339
--- /dev/null
+++ b/config/src/vespa/config/common/configupdate.cpp
@@ -0,0 +1,17 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include "configupdate.h"
+
+namespace config {
+
+ConfigUpdate::ConfigUpdate(const ConfigValue & value, bool changed, int64_t generation)
+    : _value(value),
+      _hasChanged(changed),
+      _generation(generation)
+{
+}
+
+const ConfigValue & ConfigUpdate::getValue() const { return _value; }
+bool ConfigUpdate::hasChanged() const { return _hasChanged; }
+int64_t ConfigUpdate::getGeneration() const { return _generation; }
+
+} // namespace config
diff --git a/config/src/vespa/config/common/configupdate.h b/config/src/vespa/config/common/configupdate.h
new file mode 100644
index 00000000000..ecb66990e73
--- /dev/null
+++ b/config/src/vespa/config/common/configupdate.h
@@ -0,0 +1,29 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <memory>
+#include "configvalue.h"
+
+namespace config {
+
+/**
+ * A config update contains a config value, and metadata saying if the value is
+ * changed or not.
+ */
+class ConfigUpdate
+{
+public:
+    typedef std::unique_ptr<ConfigUpdate> UP;
+    ConfigUpdate(const ConfigValue & value, bool changed, int64_t generation);
+
+    const ConfigValue & getValue() const;
+    bool hasChanged() const;
+    int64_t getGeneration() const;
+private:
+    ConfigValue _value;
+    bool _hasChanged;
+    int64_t _generation;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/common/configvalue.cpp b/config/src/vespa/config/common/configvalue.cpp
new file mode 100644
index 00000000000..6577982dc64
--- /dev/null
+++ b/config/src/vespa/config/common/configvalue.cpp
@@ -0,0 +1,76 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include "configvalue.h"
+#include "payload_converter.h"
+#include "misc.h"
+
+namespace config {
+
+ConfigValue::ConfigValue(const std::vector<vespalib::string> & lines, const vespalib::string & md5sum)
+    : _payload(),
+      _lines(lines),
+      _md5sum(md5sum)
+{}
+
+ConfigValue::ConfigValue()
+    : _payload(),
+      _lines(),
+      _md5sum()
+{}
+
+ConfigValue::ConfigValue(const PayloadPtr & payload, const vespalib::string & md5)
+    : _payload(payload),
+      _lines(),
+      _md5sum(md5)
+{
+}
+
+int
+ConfigValue::operator==(const ConfigValue & rhs) const
+{
+    return (_md5sum.compare(rhs._md5sum) == 0);
+}
+
+int
+ConfigValue::operator!=(const ConfigValue & rhs) const
+{
+    return (!(*this == rhs));
+}
+
+std::vector<vespalib::string>
+ConfigValue::getLegacyFormat() const
+{
+    std::vector<vespalib::string> lines;
+    if (_payload) {
+        const vespalib::slime::Inspector & payload(_payload->getSlimePayload());
+        PayloadConverter converter(payload);
+        lines = converter.convert();
+    } else {
+        lines = _lines;
+    }
+    return lines;
+}
+
+const vespalib::string
+ConfigValue::asJson() const {
+    const vespalib::slime::Inspector & payload(_payload->getSlimePayload());
+    return payload.toString();
+}
+
+void
+ConfigValue::serializeV1(vespalib::slime::Cursor & cursor) const
+{
+    // TODO: Remove v1 when we can bump disk format.
+    std::vector<vespalib::string> lines(getLegacyFormat());
+    for (size_t i = 0; i < lines.size(); i++) {
+        cursor.addString(vespalib::slime::Memory(lines[i]));
+    }
+}
+
+void
+ConfigValue::serializeV2(vespalib::slime::Cursor & cursor) const
+{
+    copySlimeObject(_payload->getSlimePayload(), cursor);
+}
+
+}
+
diff --git a/config/src/vespa/config/common/configvalue.h b/config/src/vespa/config/common/configvalue.h
new file mode 100644
index 00000000000..b6315c51081
--- /dev/null
+++ b/config/src/vespa/config/common/configvalue.h
@@ -0,0 +1,51 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+#include <vector>
+#include <memory>
+#include <vespa/vespalib/data/slime/slime.h>
+#include <vespa/config/frt/protocol.h>
+#include <vespa/config/configgen/configpayload.h>
+
+namespace config {
+
+typedef std::shared_ptr<const protocol::Payload> PayloadPtr;
+
+/**
+ * Internal representation of a config value. DO NOT USE THIS!!!!! Use readers
+ * if you want to instantiate config objects directly.
+ */
+class ConfigValue {
+public:
+    typedef std::unique_ptr<ConfigValue> UP;
+    ConfigValue(const std::vector<vespalib::string> & lines, const vespalib::string & md5sum);
+    ConfigValue(const PayloadPtr & data, const vespalib::string & md5sum);
+    ConfigValue();
+
+    int operator==(const ConfigValue & rhs) const;
+    int operator!=(const ConfigValue & rhs) const;
+
+    size_t numLines() const { return _lines.size();  }
+    const vespalib::string & getLine(int i) const { return _lines.at(i);  }
+    const std::vector<vespalib::string> & getLines() const { return _lines;  }
+    std::vector<vespalib::string> getLegacyFormat() const;
+    const vespalib::string asJson() const;
+    const vespalib::string getMd5() const { return _md5sum; }
+
+    void serializeV1(::vespalib::slime::Cursor & cursor) const;
+    void serializeV2(::vespalib::slime::Cursor & cursor) const;
+
+    template <typename ConfigType>
+    std::unique_ptr<ConfigType> newInstance() const;
+
+private:
+    PayloadPtr _payload;
+    std::vector<vespalib::string> _lines;
+    vespalib::string _md5sum;
+};
+
+} //namespace config
+
+#include "configvalue.hpp"
+
diff --git a/config/src/vespa/config/common/configvalue.hpp b/config/src/vespa/config/common/configvalue.hpp
new file mode 100644
index 00000000000..f464b1ddee3
--- /dev/null
+++ b/config/src/vespa/config/common/configvalue.hpp
@@ -0,0 +1,17 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+namespace config {
+
+template <typename ConfigType>
+std::unique_ptr<ConfigType>
+ConfigValue::newInstance() const
+{
+    if (_payload) {
+        const vespalib::slime::Inspector & payload(_payload->getSlimePayload());
+        return std::unique_ptr<ConfigType>(new ConfigType(config::ConfigPayload(payload)));
+    } else {
+        return std::unique_ptr<ConfigType>(new ConfigType(*this));
+    }
+}
+
+}
diff --git a/config/src/vespa/config/common/errorcode.cpp b/config/src/vespa/config/common/errorcode.cpp
new file mode 100644
index 00000000000..07907650f50
--- /dev/null
+++ b/config/src/vespa/config/common/errorcode.cpp
@@ -0,0 +1,39 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+/**
+ * @author  Gunnar Gauslaa Bergem
+ * @date    2008-05-22
+ * @version $Id: errorcode.cpp 119439 2011-04-19 09:32:27Z arnej $
+ */
+
+#include <vespa/fastos/fastos.h>
+#include "errorcode.h"
+
+namespace config {
+
+vespalib::string ErrorCode::getName(int error) {
+    switch(error) {
+    case UNKNOWN_CONFIG:            return "UNKNOWN_CONFIG";
+    case UNKNOWN_DEFINITION:        return "UNKNOWN_DEFINITION";
+    case UNKNOWN_VERSION:           return "UNKNOWN_VERSION";
+    case UNKNOWN_CONFIGID:          return "UNKNOWN_CONFIGID";
+    case UNKNOWN_DEF_MD5:           return "UNKNOWN_DEF_MD5";
+    case UNKNOWN_VESPA_VERSION:     return "UNKNOWN_VESPA_VERSION";
+    case ILLEGAL_NAME:              return "ILLEGAL_NAME";
+    case ILLEGAL_VERSION:           return "ILLEGAL_VERSION";
+    case ILLEGAL_CONFIGID:          return "ILLEGAL_CONFIGID";
+    case ILLEGAL_DEF_MD5:           return "ILLEGAL_DEF_MD5";
+    case ILLEGAL_CONFIG_MD5:        return "ILLEGAL_CONFIG_MD5";
+    case ILLEGAL_TIMEOUT:           return "ILLEGAL_TIMEOUT";
+    case ILLEGAL_TIMESTAMP:         return "ILLEGAL_TIMESTAMP";
+    case ILLEGAL_NAME_SPACE:        return "ILLEGAL_NAME_SPACE";
+    case ILLEGAL_PROTOCOL_VERSION:  return "ILLEGAL_PROTOCOL_VERSION";
+    case ILLEGAL_CLIENT_HOSTNAME:   return "ILLEGAL_CLIENT_HOSTNAME";
+    case OUTDATED_CONFIG:           return "OUTDATED_CONFIG";
+    case INTERNAL_ERROR:            return "INTERNAL_ERROR";
+    case APPLICATION_NOT_LOADED:    return "APPLICATION_NOT_LOADED";
+    case INCONSISTENT_CONFIG_MD5:   return "INCONSISTENT_CONFIG_MD5";
+    default:                        return "Unknown error";
+    }
+}
+
+}
diff --git a/config/src/vespa/config/common/errorcode.h b/config/src/vespa/config/common/errorcode.h
new file mode 100644
index 00000000000..401e68358a6
--- /dev/null
+++ b/config/src/vespa/config/common/errorcode.h
@@ -0,0 +1,52 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+/**
+ * @author  Gunnar Gauslaa Bergem
+ * @date    2008-05-22
+ * @version $Id: errorcode.h 119465 2011-04-20 15:21:46Z arnej $
+ */
+
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+
+namespace config {
+
+class ErrorCode {
+private:
+    ErrorCode();
+    ErrorCode(const ErrorCode &);
+
+public:
+    static const int UNKNOWN_CONFIG = 100000;
+    static const int UNKNOWN_DEFINITION = UNKNOWN_CONFIG + 1;
+    static const int UNKNOWN_VERSION = UNKNOWN_CONFIG + 2;
+    static const int UNKNOWN_CONFIGID = UNKNOWN_CONFIG + 3;
+    static const int UNKNOWN_DEF_MD5 = UNKNOWN_CONFIG + 4;
+    static const int UNKNOWN_VESPA_VERSION = UNKNOWN_CONFIG + 5;
+
+    static const int ILLEGAL_NAME = UNKNOWN_CONFIG + 100;
+    static const int ILLEGAL_VERSION = UNKNOWN_CONFIG + 101;
+    static const int ILLEGAL_CONFIGID = UNKNOWN_CONFIG + 102;
+    static const int ILLEGAL_DEF_MD5 = UNKNOWN_CONFIG + 103;
+    static const int ILLEGAL_CONFIG_MD5 = UNKNOWN_CONFIG + 104;
+    static const int ILLEGAL_TIMEOUT = UNKNOWN_CONFIG + 105;
+    static const int ILLEGAL_TIMESTAMP = UNKNOWN_CONFIG + 106;
+
+    static const int ILLEGAL_NAME_SPACE = UNKNOWN_CONFIG + 108;
+    static const int ILLEGAL_PROTOCOL_VERSION = UNKNOWN_CONFIG + 109;
+    static const int ILLEGAL_CLIENT_HOSTNAME = UNKNOWN_CONFIG + 110;
+
+    // hasUpdatedConfig() is true, but timestamp says the config is older than previous config
+    static const int OUTDATED_CONFIG = UNKNOWN_CONFIG + 150;
+
+    static const int INTERNAL_ERROR = UNKNOWN_CONFIG + 200;
+
+    static const int APPLICATION_NOT_LOADED = UNKNOWN_CONFIG + 300;
+
+    static const int INCONSISTENT_CONFIG_MD5 = UNKNOWN_CONFIG + 400;
+
+    static vespalib::string getName(int error);
+};
+
+}
+
diff --git a/config/src/vespa/config/common/exceptions.cpp b/config/src/vespa/config/common/exceptions.cpp
new file mode 100644
index 00000000000..d19c27b5999
--- /dev/null
+++ b/config/src/vespa/config/common/exceptions.cpp
@@ -0,0 +1,22 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "exceptions.h"
+
+namespace config {
+
+VESPA_IMPLEMENT_EXCEPTION(InvalidConfigException, vespalib::Exception);
+
+VESPA_IMPLEMENT_EXCEPTION(IllegalConfigKeyException, vespalib::Exception);
+
+VESPA_IMPLEMENT_EXCEPTION(ConfigRuntimeException, vespalib::Exception);
+
+VESPA_IMPLEMENT_EXCEPTION(InvalidConfigSourceException, vespalib::Exception);
+
+VESPA_IMPLEMENT_EXCEPTION(ConfigWriteException, vespalib::Exception);
+
+VESPA_IMPLEMENT_EXCEPTION(ConfigReadException, vespalib::Exception);
+
+VESPA_IMPLEMENT_EXCEPTION(ConfigTimeoutException, ConfigRuntimeException);
+
+}
+
diff --git a/config/src/vespa/config/common/exceptions.h b/config/src/vespa/config/common/exceptions.h
new file mode 100644
index 00000000000..c3fafab1287
--- /dev/null
+++ b/config/src/vespa/config/common/exceptions.h
@@ -0,0 +1,25 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <string>
+#include <stdexcept>
+#include <vespa/vespalib/util/exception.h>
+
+namespace config {
+
+VESPA_DEFINE_EXCEPTION(InvalidConfigException, vespalib::Exception);
+
+VESPA_DEFINE_EXCEPTION(IllegalConfigKeyException, vespalib::Exception);
+
+VESPA_DEFINE_EXCEPTION(ConfigRuntimeException, vespalib::Exception);
+
+VESPA_DEFINE_EXCEPTION(InvalidConfigSourceException, vespalib::Exception);
+
+VESPA_DEFINE_EXCEPTION(ConfigWriteException, vespalib::Exception);
+
+VESPA_DEFINE_EXCEPTION(ConfigReadException, vespalib::Exception);
+
+VESPA_DEFINE_EXCEPTION(ConfigTimeoutException, ConfigRuntimeException);
+
+}
+
diff --git a/config/src/vespa/config/common/handler.h b/config/src/vespa/config/common/handler.h
new file mode 100644
index 00000000000..ecd6351b882
--- /dev/null
+++ b/config/src/vespa/config/common/handler.h
@@ -0,0 +1,23 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#pragma once
+
+#include <memory>
+#include "configupdate.h"
+
+namespace config {
+
+/**
+ * A Handler is a component to whom you can pass an object.
+ **/
+template <typename T>
+struct Handler
+{
+    virtual void handle(std::unique_ptr<T> obj) = 0;
+    virtual ~Handler() {}
+};
+
+typedef Handler<ConfigUpdate> ConfigHandler;
+
+} // namespace config
+
diff --git a/config/src/vespa/config/common/iconfigholder.h b/config/src/vespa/config/common/iconfigholder.h
new file mode 100644
index 00000000000..b455dd9cd01
--- /dev/null
+++ b/config/src/vespa/config/common/iconfigholder.h
@@ -0,0 +1,25 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/handler.h>
+#include <vespa/config/common/provider.h>
+#include <vespa/config/common/waitable.h>
+#include <vespa/config/common/pollable.h>
+#include <vespa/config/common/interruptable.h>
+#include <vespa/config/common/configupdate.h>
+
+namespace config {
+
+class IConfigHolder : public ConfigHandler,
+                      public Provider<ConfigUpdate>,
+                      public Waitable,
+                      public Pollable,
+                      public Interruptable
+{
+public:
+    typedef std::shared_ptr<IConfigHolder> SP;
+    virtual ~IConfigHolder() { }
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/common/iconfigmanager.h b/config/src/vespa/config/common/iconfigmanager.h
new file mode 100644
index 00000000000..15ddd0f251a
--- /dev/null
+++ b/config/src/vespa/config/common/iconfigmanager.h
@@ -0,0 +1,19 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/subscribehandler.h>
+#include <vespa/config/common/cancelhandler.h>
+#include <vespa/config/common/reloadhandler.h>
+
+namespace config {
+
+class IConfigManager : public SubscribeHandler,
+                       public CancelHandler,
+                       public ReloadHandler
+{
+public:
+    virtual ~IConfigManager() { }
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/common/interruptable.h b/config/src/vespa/config/common/interruptable.h
new file mode 100644
index 00000000000..32af06c1d06
--- /dev/null
+++ b/config/src/vespa/config/common/interruptable.h
@@ -0,0 +1,19 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#pragma once
+
+#include <memory>
+
+namespace config {
+
+/**
+ * An Interruptable is a component that can be notified that it should abort its current activities.
+ */
+struct Interruptable
+{
+    virtual void interrupt() = 0;
+    virtual ~Interruptable() {}
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/common/misc.cpp b/config/src/vespa/config/common/misc.cpp
new file mode 100644
index 00000000000..fb226a9734d
--- /dev/null
+++ b/config/src/vespa/config/common/misc.cpp
@@ -0,0 +1,160 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/fastos/fastos.h>
+#include "misc.h"
+#include <vespa/vespalib/util/md5.h>
+#include <vespa/vespalib/stllike/asciistream.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.common.misc");
+
+namespace config {
+
+vespalib::string
+calculateContentMd5(const std::vector<vespalib::string> & fileContents)
+{
+    vespalib::string normalizedLines;
+    int compact_md5size = 16;
+    unsigned char md5sum[compact_md5size];
+    vespalib::asciistream s;
+
+    // remove comments, trailing spaces and empty lines
+    // TODO: Remove multiple spaces and space before comma, like in Java
+    for (int i = 0; i < (int)fileContents.size(); i++) {
+        std::string line = fileContents[i];
+        line = line.erase(line.find_last_not_of("#") + 1);
+        line = line.erase(line.find_last_not_of(" ") + 1);
+        if (line.size() > 0) {
+            line += "\n";
+            normalizedLines += line;
+        }
+    }
+    fastc_md5sum((const unsigned char*)normalizedLines.c_str(), normalizedLines.size(), md5sum);
+
+    // convert to 32 character hex string
+    for (int i = 0; i < compact_md5size; i++) {
+        if (md5sum[i] < 16) {
+            s << "0";
+        }
+        s << std::hex << (int)md5sum[i];
+    }
+    return s.str();
+}
+
+bool
+isGenerationNewer(int64_t newGen, int64_t oldGen)
+{
+    return (newGen > oldGen) || (newGen == 0);
+}
+
+void
+throwInvalid(const char *format, ...)
+    throw(InvalidConfigException)
+{
+    char buf[4000];
+    va_list args;
+
+    va_start(args, format);
+    vsnprintf(buf, sizeof buf, format, args);
+    va_end(args);
+    LOG(warning, "Error in configuration: %s", buf);
+
+    throw InvalidConfigException(buf);
+}
+
+using namespace vespalib::slime;
+
+void copySlimeArray(const Inspector & src, Cursor & dest);
+
+class CopyObjectTraverser : public ObjectTraverser
+{
+private:
+    Cursor & _dest;
+public:
+    CopyObjectTraverser(Cursor & dest) : _dest(dest) {}
+    void field(const Memory & symbol, const Inspector & inspector) {
+        switch(inspector.type().getId()) {
+            case NIX::ID:
+                _dest.addNix();
+                break;
+            case BOOL::ID:
+                _dest.setBool(symbol, inspector.asBool());
+                break;
+            case LONG::ID:
+                _dest.setLong(symbol, inspector.asLong());
+                break;
+            case DOUBLE::ID:
+                _dest.setDouble(symbol, inspector.asDouble());
+                break;
+            case STRING::ID:
+                _dest.setString(symbol, inspector.asString());
+                break;
+            case DATA::ID:
+                _dest.setData(symbol, inspector.asData());
+                break;
+            case ARRAY::ID:
+                copySlimeArray(inspector, _dest.setArray(symbol));
+                break;
+            case OBJECT::ID:
+                copySlimeObject(inspector, _dest.setObject(symbol));
+                break;
+        }
+    }
+};
+
+class CopyArrayTraverser : public ArrayTraverser
+{
+private:
+    Cursor & _dest;
+public:
+    CopyArrayTraverser(Cursor & dest) : _dest(dest) {}
+    void entry(size_t idx, const Inspector & inspector) {
+        (void) idx;
+        switch(inspector.type().getId()) {
+            case NIX::ID:
+                _dest.addNix();
+                break;
+            case BOOL::ID:
+                _dest.addBool(inspector.asBool());
+                break;
+            case LONG::ID:
+                _dest.addLong(inspector.asLong());
+                break;
+            case DOUBLE::ID:
+                _dest.addDouble(inspector.asDouble());
+                break;
+            case STRING::ID:
+                _dest.addString(inspector.asString());
+                break;
+            case DATA::ID:
+                _dest.addData(inspector.asData());
+                break;
+            case ARRAY::ID:
+                copySlimeArray(inspector, _dest.addArray());
+                break;
+            case OBJECT::ID:
+                copySlimeObject(inspector, _dest.addObject());
+                break;
+        }
+    }
+};
+
+void copySlimeArray(const Inspector & src, Cursor & dest)
+{
+    if (src.type().getId() != ARRAY::ID) {
+        throw vespalib::IllegalArgumentException("Source inspector is not of type array");
+    }
+    CopyArrayTraverser traverser(dest);
+    src.traverse(traverser);
+}
+
+
+void copySlimeObject(const Inspector & src, Cursor & dest)
+{
+    if (src.type().getId() != OBJECT::ID) {
+        throw vespalib::IllegalArgumentException("Source inspector is not of type object");
+    }
+    CopyObjectTraverser traverser(dest);
+    src.traverse(traverser);
+}
+
+}
diff --git a/config/src/vespa/config/common/misc.h b/config/src/vespa/config/common/misc.h
new file mode 100644
index 00000000000..0a9d6182299
--- /dev/null
+++ b/config/src/vespa/config/common/misc.h
@@ -0,0 +1,31 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+#include <vespa/vespalib/data/slime/slime.h>
+#include <vector>
+#include "exceptions.h"
+#include "configkey.h"
+
+namespace config {
+
+/**
+ * Miscellaneous utility functions specific to config.
+ */
+vespalib::string calculateContentMd5(const std::vector<vespalib::string> & fileContents);
+
+bool isGenerationNewer(int64_t newGen, int64_t oldGen);
+
+// Helper for throwing invalid config exception
+void throwInvalid(const char *fmt, ...) throw (InvalidConfigException)
+    __attribute__((format(printf, 1, 2))) __attribute__((noreturn));
+
+typedef std::shared_ptr<const vespalib::Slime> SlimePtr;
+
+/**
+ * Copy slime objects from under src to dest, recursively.
+ */
+void copySlimeObject(const vespalib::slime::Inspector & src, vespalib::slime::Cursor & dest);
+
+} // namespace config
+
diff --git a/config/src/vespa/config/common/payload_converter.cpp b/config/src/vespa/config/common/payload_converter.cpp
new file mode 100644
index 00000000000..2f7feb6a1b0
--- /dev/null
+++ b/config/src/vespa/config/common/payload_converter.cpp
@@ -0,0 +1,147 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include "payload_converter.h"
+
+using namespace vespalib::slime;
+
+namespace config {
+
+PayloadConverter::PayloadConverter(const Inspector & inspector)
+    : _inspector(inspector),
+      _lines()
+{}
+
+const std::vector<vespalib::string> &
+PayloadConverter::convert()
+{
+    _lines.clear();
+    ObjectTraverser & traverser(*this);
+    _inspector.traverse(traverser);
+    return _lines;
+}
+
+void
+PayloadConverter::encodeObject(const Memory & symbol, const Inspector & object)
+{
+    _nodeStack.push_back(Node(symbol.make_string()));
+    ObjectTraverser & traverser(*this);
+    object.traverse(traverser);
+    _nodeStack.pop_back();
+}
+
+void
+PayloadConverter::encodeArray(const Memory & symbol, const Inspector & array)
+{
+    _nodeStack.push_back(Node(symbol.make_string()));
+    ArrayTraverser & traverser(*this);
+    array.traverse(traverser);
+    _nodeStack.pop_back();
+}
+
+void
+PayloadConverter::encode(const Inspector & inspector)
+{
+    ObjectTraverser & traverser(*this);
+    switch (inspector.type().getId()) {
+        case OBJECT::ID:
+            inspector.traverse(traverser);
+            break;
+        default:
+            encodeValue(inspector);
+            break;
+    }
+}
+
+void
+PayloadConverter::encode(const Memory & symbol, const Inspector & inspector)
+{
+    switch (inspector.type().getId()) {
+        case OBJECT::ID:
+            encodeObject(symbol, inspector);
+            break;
+        case ARRAY::ID:
+            encodeArray(symbol, inspector);
+            break;
+        default:
+            _nodeStack.push_back(Node(symbol.make_string()));
+            encodeValue(inspector);
+            _nodeStack.pop_back();
+            break;
+    }
+}
+
+void
+PayloadConverter::field(const Memory& symbol, const Inspector & inspector)
+{
+    encode(symbol, inspector);
+}
+
+void
+PayloadConverter::entry(size_t idx, const Inspector & inspector)
+{
+    _nodeStack.push_back(Node(idx));
+    encode(inspector);
+    _nodeStack.pop_back();
+}
+
+void
+PayloadConverter::printPrefix()
+{
+    for (size_t i = 0; i < _nodeStack.size(); i++) {
+        bool first = (i == 0);
+        Node & node(_nodeStack[i]);
+        if (node.arrayIndex >= 0) {
+            encodeString("[");
+            encodeLong(node.arrayIndex);
+            encodeString("]");
+        } else {
+            if (!first) {
+                encodeString(".");
+            }
+            encodeString(node.name);
+        }
+    }
+    encodeString(" ");
+}
+
+void
+PayloadConverter::encodeValue(const Inspector & value)
+{
+    printPrefix();
+    switch (value.type().getId()) {
+        case STRING::ID:
+            encodeQuotedString(value.asString().make_string());
+            break;
+        case LONG::ID:
+            encodeLong(value.asLong());
+            break;
+        case DOUBLE::ID:
+            encodeDouble(value.asDouble());
+            break;
+        case BOOL::ID:
+            encodeBool(value.asBool());
+            break;
+    }
+    _lines.push_back(_buf.str());
+    _buf.clear();
+}
+
+void
+PayloadConverter::encodeString(const vespalib::string & value)
+{
+    _buf << value;
+}
+
+void PayloadConverter::encodeLong(long value) { _buf << value; }
+void PayloadConverter::encodeDouble(double value) { _buf << value; }
+void PayloadConverter::encodeBool(bool value) { _buf << (value ? "true" : "false"); }
+
+void
+PayloadConverter::encodeQuotedString(const vespalib::string & value)
+{
+    encodeString("\"");
+    encodeString(value);
+    encodeString("\"");
+}
+
+
+} // namespace config
diff --git a/config/src/vespa/config/common/payload_converter.h b/config/src/vespa/config/common/payload_converter.h
new file mode 100644
index 00000000000..e53705fc633
--- /dev/null
+++ b/config/src/vespa/config/common/payload_converter.h
@@ -0,0 +1,47 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/data/slime/slime.h>
+#include <vespa/vespalib/stllike/string.h>
+#include <vespa/vespalib/stllike/asciistream.h>
+
+namespace config {
+
+/**
+ * Converts slime payload to cfg format.
+ * XXX: Maps are not supported by this converter.
+ */
+class PayloadConverter : public vespalib::slime::ObjectTraverser, public vespalib::slime::ArrayTraverser {
+public:
+    PayloadConverter(const vespalib::slime::Inspector & inspector);
+    const std::vector<vespalib::string> & convert();
+    void field(const vespalib::slime::Memory & symbol, const vespalib::slime::Inspector & inspector);
+    void entry(size_t idx, const vespalib::slime::Inspector & inspector);
+private:
+    void printPrefix();
+    void encode(const vespalib::slime::Inspector & inspector);
+    void encode(const vespalib::slime::Memory & symbol, const vespalib::slime::Inspector & inspector);
+    void encodeObject(const vespalib::slime::Memory & symbol, const vespalib::slime::Inspector & object);
+    void encodeArray(const vespalib::slime::Memory & symbol, const vespalib::slime::Inspector & object);
+    void encodeValue(const vespalib::slime::Inspector & value);
+    void encodeString(const vespalib::string & value);
+    void encodeQuotedString(const vespalib::string & value);
+    void encodeLong(long value);
+    void encodeDouble(double value);
+    void encodeBool(bool value);
+    struct Node {
+        vespalib::string name;
+        int arrayIndex;
+        Node(const vespalib::string & nm, int idx) : name(nm), arrayIndex(idx) {}
+        Node(int idx) : name(""), arrayIndex(idx) {}
+        Node(const vespalib::string & nm) : name(nm), arrayIndex(-1) {}
+    };
+    const vespalib::slime::Inspector & _inspector;
+    std::vector<vespalib::string> _lines;
+    typedef std::vector<Node> NodeStack;
+    NodeStack _nodeStack;
+    vespalib::asciistream _buf;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/common/pollable.h b/config/src/vespa/config/common/pollable.h
new file mode 100644
index 00000000000..8814a3a77ac
--- /dev/null
+++ b/config/src/vespa/config/common/pollable.h
@@ -0,0 +1,20 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#pragma once
+
+#include <memory>
+
+namespace config {
+
+/**
+ * A Pollable is a component that can be polled, and returns either true or
+ * false.
+ */
+struct Pollable
+{
+    virtual bool poll() = 0;
+    virtual ~Pollable() {}
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/common/provider.h b/config/src/vespa/config/common/provider.h
new file mode 100644
index 00000000000..5eebcc614f4
--- /dev/null
+++ b/config/src/vespa/config/common/provider.h
@@ -0,0 +1,20 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#pragma once
+
+#include <memory>
+
+namespace config {
+
+/**
+ * A Provider is a component from which you can request an object.
+ **/
+template <typename T>
+struct Provider
+{
+    virtual std::unique_ptr<T> provide() = 0;
+    virtual ~Provider() {}
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/common/reloadhandler.h b/config/src/vespa/config/common/reloadhandler.h
new file mode 100644
index 00000000000..e64264fb2c0
--- /dev/null
+++ b/config/src/vespa/config/common/reloadhandler.h
@@ -0,0 +1,16 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+namespace config {
+
+struct ReloadHandler
+{
+    /**
+     * Reload any configs with a given generation.
+     */
+    virtual void reload(int64_t generation) = 0;
+    virtual ~ReloadHandler() { }
+};
+
+}
+
diff --git a/config/src/vespa/config/common/source.h b/config/src/vespa/config/common/source.h
new file mode 100644
index 00000000000..a1c0633d47b
--- /dev/null
+++ b/config/src/vespa/config/common/source.h
@@ -0,0 +1,25 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/fastos/fastos.h>
+#include <memory>
+
+namespace config {
+
+/*
+ * Class representing a source from which constructs config requests and request
+ * handlers.
+ */
+class Source {
+public:
+    typedef std::unique_ptr<Source> UP;
+
+    virtual void getConfig() = 0;
+    virtual void reload(int64_t generation) = 0;
+    virtual void close() = 0;
+
+    virtual ~Source() { }
+};
+
+} // namespace common
+
diff --git a/config/src/vespa/config/common/sourcefactory.h b/config/src/vespa/config/common/sourcefactory.h
new file mode 100644
index 00000000000..bfa009f287f
--- /dev/null
+++ b/config/src/vespa/config/common/sourcefactory.h
@@ -0,0 +1,22 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <memory>
+#include "source.h"
+#include "configkey.h"
+#include "iconfigholder.h"
+
+namespace config {
+
+/*
+ * Source factory, creating possible config sources.
+ */
+class SourceFactory {
+public:
+    typedef std::unique_ptr<SourceFactory> UP;
+    virtual Source::UP createSource(const IConfigHolder::SP & holder, const ConfigKey & key) const = 0;
+    virtual ~SourceFactory() { }
+};
+
+} // namespace common
+
diff --git a/config/src/vespa/config/common/subscribehandler.h b/config/src/vespa/config/common/subscribehandler.h
new file mode 100644
index 00000000000..4177ffd2b3c
--- /dev/null
+++ b/config/src/vespa/config/common/subscribehandler.h
@@ -0,0 +1,25 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/subscription/configsubscription.h>
+#include <vespa/config/common/configkey.h>
+
+namespace config {
+
+struct SubscribeHandler
+{
+    /**
+     * Subscribes to a spesific config given by a subscription.
+     * If the subscribe call is successful, the callback handler will be called
+     * with the new config.
+     *
+     * @param key the subscription key to subscribe to.
+     * @param timeoutInMillis the timeout of the subscribe call.
+     * @return subscription object containing data relevant to client
+     */
+    virtual ConfigSubscription::SP subscribe(const ConfigKey & key, uint64_t timeoutInMillis) = 0;
+    virtual ~SubscribeHandler() { }
+};
+
+}
+
diff --git a/config/src/vespa/config/common/timingvalues.cpp b/config/src/vespa/config/common/timingvalues.cpp
new file mode 100644
index 00000000000..13844bcdfe9
--- /dev/null
+++ b/config/src/vespa/config/common/timingvalues.cpp
@@ -0,0 +1,54 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+/**
+ * @author  Gunnar Gauslaa Bergem
+ * @date    2008-05-22
+ * @version $Id: timingvalues.cpp 119439 2011-04-19 09:32:27Z arnej $
+ */
+
+#include <vespa/fastos/fastos.h>
+#include "timingvalues.h"
+
+namespace config {
+
+TimingValues::TimingValues()
+    : successTimeout(600000),
+      errorTimeout(25000),
+      initialTimeout(15000),
+      subscribeTimeout(DEFAULT_SUBSCRIBE_TIMEOUT),
+      fixedDelay(5000),
+      successDelay(250),
+      unconfiguredDelay(1000),
+      configuredErrorDelay(15000),
+      maxDelayMultiplier(10),
+      transientDelay(10000),
+      fatalDelay(60000)
+{
+}
+
+
+TimingValues::TimingValues(uint64_t initSuccessTimeout,
+                           uint64_t initErrorTimeout,
+                           uint64_t initInitialTimeout,
+                           uint64_t initSubscribeTimeout,
+                           uint64_t initFixedDelay,
+                           uint64_t initSuccessDelay,
+                           uint64_t initUnconfiguredDelay,
+                           uint64_t initConfiguredErrorDelay,
+                           unsigned int initMaxDelayMultiplier,
+                           uint64_t initTransientDelay,
+                           uint64_t initFatalDelay)
+    : successTimeout(initSuccessTimeout),
+      errorTimeout(initErrorTimeout),
+      initialTimeout(initInitialTimeout),
+      subscribeTimeout(initSubscribeTimeout),
+      fixedDelay(initFixedDelay),
+      successDelay(initSuccessDelay),
+      unconfiguredDelay(initUnconfiguredDelay),
+      configuredErrorDelay(initConfiguredErrorDelay),
+      maxDelayMultiplier(initMaxDelayMultiplier),
+      transientDelay(initTransientDelay),
+      fatalDelay(initFatalDelay)
+{
+}
+
+}
diff --git a/config/src/vespa/config/common/timingvalues.h b/config/src/vespa/config/common/timingvalues.h
new file mode 100644
index 00000000000..78a64050a22
--- /dev/null
+++ b/config/src/vespa/config/common/timingvalues.h
@@ -0,0 +1,50 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+/**
+ * @author  Gunnar Gauslaa Bergem
+ * @date    2008-05-22
+ * @version $Id: timingvalues.h 119465 2011-04-20 15:21:46Z arnej $
+ */
+
+#pragma once
+
+#include <vespa/fastos/fastos.h>
+
+namespace config {
+
+static const uint64_t DEFAULT_NEXTCONFIG_TIMEOUT = 55000;
+static const uint64_t DEFAULT_SUBSCRIBE_TIMEOUT = 55000;
+static const uint64_t DEFAULT_GETCONFIGS_TIMEOUT = 55000;
+
+
+struct TimingValues
+{
+    uint64_t successTimeout;        // Timeout when previous config request was a success.
+    uint64_t errorTimeout;          // Timeout when previous config request was an error.
+    uint64_t initialTimeout;        // Timeout used when requesting config for the first time.
+    uint64_t subscribeTimeout;    // Timeout used to find out when to give up unsubscribe.
+
+    uint64_t fixedDelay;            // Fixed delay between config requests.
+    uint64_t successDelay;          // Delay if until next request after successful getConfig.
+    uint64_t unconfiguredDelay;     // Delay if failed and client not yet configured.
+    uint64_t configuredErrorDelay;  // Delay if failed but client has gotten config for the first time earlier.
+    unsigned int maxDelayMultiplier;        // Max multiplier when trying to get config.
+
+    uint64_t transientDelay;        // Delay between connection reuse if transient error.
+    uint64_t fatalDelay;            // Delay between connection reuse if fatal error.
+
+    TimingValues();
+    TimingValues(uint64_t initSuccessTimeout,
+                 uint64_t initerrorTimeout,
+                 uint64_t initInitialTimeout,
+                 uint64_t initSubscribeTimeout,
+                 uint64_t initFixedDelay,
+                 uint64_t initSuccessDelay,
+                 uint64_t initUnconfiguredDelay,
+                 uint64_t initConfiguredErrorDelay,
+                 unsigned int initMaxDelayMultiplier,
+                 uint64_t initTransientDelay,
+                 uint64_t initFatalDelay);
+};
+
+}
+
diff --git a/config/src/vespa/config/common/trace.cpp b/config/src/vespa/config/common/trace.cpp
new file mode 100644
index 00000000000..70f5ddb85a2
--- /dev/null
+++ b/config/src/vespa/config/common/trace.cpp
@@ -0,0 +1,109 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include "trace.h"
+#include <vespa/vespalib/trace/slime_trace_serializer.h>
+#include <vespa/vespalib/trace/slime_trace_deserializer.h>
+
+using namespace vespalib;
+using namespace vespalib::slime;
+
+namespace config {
+
+struct SystemClock : public Clock
+{
+    int64_t currentTimeMillis() const {
+        fastos::TimeStamp ts(fastos::ClockSystem::now());
+        return ts.ms();
+    }
+};
+
+static SystemClock systemClock;
+
+const Memory Trace::TRACELOG("traceLog");
+const Memory Trace::TRACELEVEL("traceLevel");
+
+Trace::Trace(const Trace & other)
+    : _root(other._root),
+      _traceLevel(other._traceLevel),
+      _clock(other._clock)
+{
+}
+
+Trace::Trace()
+    : _root(),
+      _traceLevel(0),
+      _clock(systemClock)
+{
+}
+
+
+Trace::Trace(uint32_t traceLevel)
+    : _traceLevel(traceLevel),
+      _clock(systemClock)
+{
+}
+
+
+Trace::Trace(uint32_t traceLevel, const Clock & clock)
+    : _traceLevel(traceLevel),
+      _clock(clock)
+{
+}
+
+void
+Trace::deserialize(const Inspector & inspector)
+{
+    _traceLevel = inspector[TRACELEVEL].asLong();
+    deserializeTraceLog(inspector[TRACELOG]);
+}
+
+void
+Trace::deserializeTraceLog(const Inspector & root)
+{
+    SlimeTraceDeserializer deserializer(root);
+    _root = deserializer.deserialize();
+}
+
+bool
+Trace::shouldTrace(uint32_t level) const
+{
+    return (level <= _traceLevel);
+}
+
+void
+Trace::trace(uint32_t level, const vespalib::string & message)
+{
+    if (shouldTrace(level)) {
+        _root.addChild(message, _clock.currentTimeMillis());
+    }
+}
+
+void
+Trace::serialize(Cursor & cursor) const
+{
+    cursor.setLong(TRACELEVEL, _traceLevel);
+    SlimeTraceSerializer serializer(cursor.setObject(TRACELOG));
+    _root.accept(serializer);
+}
+
+void
+Trace::serializeTraceLog(Cursor & array) const
+{
+    for (uint32_t i(0); i < _root.getNumChildren(); i++) {
+        SlimeTraceSerializer serializer(array.addObject());
+        _root.getChild(i).accept(serializer);
+    }
+}
+
+vespalib::string
+Trace::toString() const
+{
+    Slime slime;
+    serializeTraceLog(slime.setArray());
+    SimpleBuffer buf;
+    JsonFormat::encode(slime.get(), buf, false);
+    return buf.get().make_string();
+}
+
+
+} // namespace config
diff --git a/config/src/vespa/config/common/trace.h b/config/src/vespa/config/common/trace.h
new file mode 100644
index 00000000000..268d46d0de6
--- /dev/null
+++ b/config/src/vespa/config/common/trace.h
@@ -0,0 +1,50 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/data/slime/slime.h>
+#include <vespa/vespalib/trace/tracenode.h>
+#include <vespa/vespalib/stllike/string.h>
+#include <memory>
+
+namespace config {
+
+/**
+ * Clock interface for acquiring time.
+ */
+struct Clock {
+    virtual int64_t currentTimeMillis() const = 0;
+    virtual ~Clock() {}
+};
+
+/**
+ * A simple trace interface which can be used to create a serial trace log of events. Each entry is given a timestamp. The trace
+ * can be serialized to/constructed from slime. Is not thread safe.
+ */
+class Trace
+{
+public:
+    Trace(const Trace & other);
+    Trace();
+    Trace(uint32_t traceLevel);
+    Trace(uint32_t traceLevel, const Clock & clock);
+
+    bool shouldTrace(uint32_t level) const;
+    void trace(uint32_t level, const vespalib::string & message);
+
+    void serialize(vespalib::slime::Cursor & cursor) const;
+    void deserialize(const vespalib::slime::Inspector & inspector);
+    const vespalib::TraceNode & getRoot() const { return _root; }
+
+    vespalib::string toString() const;
+private:
+    void serializeTraceLog(vespalib::slime::Cursor & array) const;
+    void deserializeTraceLog(const vespalib::slime::Inspector & inspector);
+    static const vespalib::slime::Memory TRACELOG;
+    static const vespalib::slime::Memory TRACELEVEL;
+    vespalib::TraceNode _root;
+    uint32_t _traceLevel;
+    const Clock & _clock;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/common/vespa_version.cpp b/config/src/vespa/config/common/vespa_version.cpp
new file mode 100644
index 00000000000..595f4dfd23b
--- /dev/null
+++ b/config/src/vespa/config/common/vespa_version.cpp
@@ -0,0 +1,41 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "vespa_version.h"
+
+#ifndef V_TAG_COMPONENT
+#define V_TAG_COMPONENT "1.0.0"
+#endif
+
+namespace config {
+
+const VespaVersion currentVersion(VespaVersion::fromString(vespalib::string(V_TAG_COMPONENT)));
+
+
+VespaVersion::VespaVersion(const VespaVersion & vespaVersion)
+    : _versionString(vespaVersion._versionString)
+{
+}
+
+VespaVersion::VespaVersion(const vespalib::string & versionString)
+    : _versionString(versionString)
+{
+}
+
+VespaVersion
+VespaVersion::fromString(const vespalib::string & versionString)
+{
+    return VespaVersion(versionString);
+}
+
+const VespaVersion &
+VespaVersion::getCurrentVersion() {
+    return currentVersion;
+}
+
+const vespalib::string &
+VespaVersion::toString() const
+{
+    return _versionString;
+}
+
+}
diff --git a/config/src/vespa/config/common/vespa_version.h b/config/src/vespa/config/common/vespa_version.h
new file mode 100644
index 00000000000..eca173793d1
--- /dev/null
+++ b/config/src/vespa/config/common/vespa_version.h
@@ -0,0 +1,24 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+
+namespace config {
+
+/**
+ * Represents a version used in config protocol
+ **/
+struct VespaVersion
+{
+public:
+    static VespaVersion fromString(const vespalib::string & versionString);
+    static const VespaVersion & getCurrentVersion();
+    VespaVersion(const VespaVersion & version);
+    const vespalib::string & toString() const;
+private:
+    VespaVersion(const vespalib::string & versionString);
+    vespalib::string _versionString;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/common/waitable.h b/config/src/vespa/config/common/waitable.h
new file mode 100644
index 00000000000..0a306d572f8
--- /dev/null
+++ b/config/src/vespa/config/common/waitable.h
@@ -0,0 +1,19 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#pragma once
+
+#include <memory>
+
+namespace config {
+
+/**
+ * A Waitable is a component that can be used to wait for some event to happen.
+ */
+struct Waitable
+{
+    virtual bool wait(uint64_t timeoutInMillis) = 0;
+    virtual ~Waitable() {}
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/config.h b/config/src/vespa/config/config.h
new file mode 100644
index 00000000000..b7331a04d9a
--- /dev/null
+++ b/config/src/vespa/config/config.h
@@ -0,0 +1,28 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/subscription/configsubscriber.h>
+#include <vespa/config/subscription/confighandle.h>
+#include <vespa/config/subscription/sourcespec.h>
+#include <vespa/config/subscription/configuri.h>
+#include <vespa/config/helper/configgetter.h>
+#include <vespa/config/helper/configfetcher.h>
+#include <vespa/config/common/exceptions.h>
+#include <vespa/config/common/misc.h>
+#include <vespa/config/retriever/configretriever.h>
+
+/*! \mainpage Cloud Config API for C++
+ *
+ * /section Introduction
+ *
+ * This document is provided as an API reference to use when developing with the
+ * C++ config API.
+ */
+
+/**
+ * @section DESCRIPTION
+ *
+ * This file contains all necessary includes as well as functions used to
+ * subscribe to and retrieve config.
+ */
+
diff --git a/config/src/vespa/config/configgen/.gitignore b/config/src/vespa/config/configgen/.gitignore
new file mode 100644
index 00000000000..7e7c0fe7fae
--- /dev/null
+++ b/config/src/vespa/config/configgen/.gitignore
@@ -0,0 +1,2 @@
+/.depend
+/Makefile
diff --git a/config/src/vespa/config/configgen/CMakeLists.txt b/config/src/vespa/config/configgen/CMakeLists.txt
new file mode 100644
index 00000000000..487c7293240
--- /dev/null
+++ b/config/src/vespa/config/configgen/CMakeLists.txt
@@ -0,0 +1,6 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_library(config_configgen OBJECT
+    SOURCES
+    value_converter.cpp
+    DEPENDS
+)
diff --git a/config/src/vespa/config/configgen/configinstance.h b/config/src/vespa/config/configgen/configinstance.h
new file mode 100644
index 00000000000..1e0d796c005
--- /dev/null
+++ b/config/src/vespa/config/configgen/configinstance.h
@@ -0,0 +1,29 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <memory>
+#include <vespa/vespalib/stllike/string.h>
+
+namespace config {
+
+class ConfigDataBuffer;
+
+/**
+ * Interface implemented by all generated config objects.
+ */
+class ConfigInstance {
+public:
+    typedef std::unique_ptr<ConfigInstance> UP;
+    typedef std::shared_ptr<ConfigInstance> SP;
+    // Static for this instance's type
+    virtual const vespalib::string & defName() const = 0;
+    virtual const vespalib::string & defMd5() const = 0;
+    virtual const vespalib::string & defNamespace() const = 0;
+
+    virtual void serialize(ConfigDataBuffer & buffer) const = 0;
+
+    virtual ~ConfigInstance() { }
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/configgen/configpayload.h b/config/src/vespa/config/configgen/configpayload.h
new file mode 100644
index 00000000000..411fdc0d443
--- /dev/null
+++ b/config/src/vespa/config/configgen/configpayload.h
@@ -0,0 +1,19 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/data/slime/slime.h>
+
+namespace config {
+
+class ConfigPayload {
+public:
+    ConfigPayload(const ::vespalib::slime::Inspector & inspector)
+        : _inspector(inspector)
+    {}
+    const ::vespalib::slime::Inspector & get() const { return _inspector; }
+private:
+    const ::vespalib::slime::Inspector & _inspector;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/configgen/map_inserter.h b/config/src/vespa/config/configgen/map_inserter.h
new file mode 100644
index 00000000000..d03cf4eb6cd
--- /dev/null
+++ b/config/src/vespa/config/configgen/map_inserter.h
@@ -0,0 +1,28 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <memory>
+#include <vespa/vespalib/stllike/string.h>
+#include <vespa/vespalib/data/slime/slime.h>
+#include "value_converter.h"
+#include <map>
+
+namespace config {
+
+namespace internal {
+
+template<typename T, typename Converter = config::internal::ValueConverter<T> >
+class MapInserter : public ::vespalib::slime::ObjectTraverser {
+public:
+    MapInserter(std::map<vespalib::string, T> & map);
+    void field(const ::vespalib::slime::Memory & symbol, const ::vespalib::slime::Inspector & inspector);
+private:
+    std::map<vespalib::string, T> & _map;
+};
+
+} // namespace internal
+
+} // namespace config
+
+#include "map_inserter.hpp"
+
diff --git a/config/src/vespa/config/configgen/map_inserter.hpp b/config/src/vespa/config/configgen/map_inserter.hpp
new file mode 100644
index 00000000000..cf1f7150041
--- /dev/null
+++ b/config/src/vespa/config/configgen/map_inserter.hpp
@@ -0,0 +1,21 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace config {
+
+namespace internal {
+
+template<typename T, typename Converter>
+MapInserter<T, Converter>::MapInserter(std::map<vespalib::string, T> & map)
+    : _map(map)
+{}
+
+template<typename T, typename Converter>
+void
+MapInserter<T, Converter>::field(const ::vespalib::slime::Memory & symbol, const ::vespalib::slime::Inspector & inspector)
+{
+    Converter converter;
+    _map[symbol.make_string()] = converter(inspector);
+}
+
+} // namespace internal
+
+}
diff --git a/config/src/vespa/config/configgen/value_converter.cpp b/config/src/vespa/config/configgen/value_converter.cpp
new file mode 100644
index 00000000000..6b7438bba02
--- /dev/null
+++ b/config/src/vespa/config/configgen/value_converter.cpp
@@ -0,0 +1,65 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/config/common/exceptions.h>
+#include "value_converter.h"
+
+using namespace vespalib;
+using namespace vespalib::slime;
+
+namespace config {
+
+namespace internal {
+
+template<>
+int32_t convertValue(const ::vespalib::slime::Inspector & __inspector) {
+    switch (__inspector.type().getId()) {
+        case LONG::ID:   return static_cast<int32_t>(__inspector.asLong());
+        case DOUBLE::ID: return static_cast<int32_t>(__inspector.asDouble());
+        case STRING::ID: return static_cast<int32_t>(strtoll(__inspector.asString().make_string().c_str(), 0, 0));
+    }
+    throw InvalidConfigException("Expected int32_t, but got incompatible config type " + __inspector.type().getId());
+}
+
+template<>
+int64_t convertValue(const ::vespalib::slime::Inspector & __inspector) {
+    switch (__inspector.type().getId()) {
+        case LONG::ID:   return static_cast<int64_t>(__inspector.asLong());
+        case DOUBLE::ID: return static_cast<int64_t>(__inspector.asDouble());
+        case STRING::ID: return static_cast<int64_t>(strtoll(__inspector.asString().make_string().c_str(), 0, 0));
+    }
+    throw InvalidConfigException("Expected int64_t, but got incompatible config type " + __inspector.type().getId());
+}
+
+template<>
+double convertValue(const ::vespalib::slime::Inspector & __inspector) {
+    switch (__inspector.type().getId()) {
+        case LONG::ID:   return static_cast<double>(__inspector.asLong());
+        case DOUBLE::ID: return static_cast<double>(__inspector.asDouble());
+        case STRING::ID: return static_cast<double>(strtod(__inspector.asString().make_string().c_str(), 0));
+    }
+    throw InvalidConfigException("Expected double, but got incompatible config type " + __inspector.type().getId());
+}
+
+template<>
+bool convertValue(const ::vespalib::slime::Inspector & __inspector) {
+    switch (__inspector.type().getId()) {
+        case BOOL::ID:   return __inspector.asBool();
+        case STRING::ID:
+            vespalib::string s(__inspector.asString().make_string());
+            return s.compare("true") == 0 ? true : false;
+    }
+    throw InvalidConfigException("Expected bool, but got incompatible config type " + __inspector.type().getId());
+}
+
+template<>
+vespalib::string convertValue(const ::vespalib::slime::Inspector & __inspector) { return __inspector.asString().make_string(); }
+
+void
+requireValid(const vespalib::string & __fieldName, const ::vespalib::slime::Inspector & __inspector) {
+    if (!__inspector.valid()) {
+        throw ::config::InvalidConfigException("Value for '" + __fieldName + "' required but not found");
+    }
+}
+
+}
+
+}
diff --git a/config/src/vespa/config/configgen/value_converter.h b/config/src/vespa/config/configgen/value_converter.h
new file mode 100644
index 00000000000..c951f558781
--- /dev/null
+++ b/config/src/vespa/config/configgen/value_converter.h
@@ -0,0 +1,48 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+#include "configpayload.h"
+
+namespace config {
+
+namespace internal {
+
+void requireValid(const vespalib::string & __fieldName, const ::vespalib::slime::Inspector & __inspector);
+
+template<typename T>
+T convertValue(const ::vespalib::slime::Inspector & __inspector) { return T(::config::ConfigPayload(__inspector)); }
+
+template<>
+int32_t convertValue(const ::vespalib::slime::Inspector & __inspector);
+
+template<>
+int64_t convertValue(const ::vespalib::slime::Inspector & __inspector);
+
+template<>
+double convertValue(const ::vespalib::slime::Inspector & __inspector);
+
+template<>
+bool convertValue(const ::vespalib::slime::Inspector & __inspector);
+
+template<>
+vespalib::string convertValue(const ::vespalib::slime::Inspector & __inspector);
+
+template<typename T>
+struct ValueConverter {
+    T operator()(const vespalib::string & __fieldName, const ::vespalib::slime::Inspector & __inspector) {
+        requireValid(__fieldName, __inspector);
+        return convertValue<T>(__inspector);
+    }
+    T operator()(const ::vespalib::slime::Inspector & __inspector) {
+        return __inspector.valid() ? convertValue<T>(__inspector) : T();
+    }
+    T operator()(const ::vespalib::slime::Inspector & __inspector, T __t) {
+        return __inspector.valid() ? convertValue<T>(__inspector) : __t;
+    }
+};
+
+} // namespace internal
+
+} // namespace config
+
diff --git a/config/src/vespa/config/configgen/vector_inserter.h b/config/src/vespa/config/configgen/vector_inserter.h
new file mode 100644
index 00000000000..36d324f3555
--- /dev/null
+++ b/config/src/vespa/config/configgen/vector_inserter.h
@@ -0,0 +1,27 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <memory>
+#include <vespa/vespalib/stllike/string.h>
+#include <vespa/vespalib/data/slime/slime.h>
+#include "value_converter.h"
+
+namespace config {
+
+namespace internal {
+
+template<typename T, typename Converter = ::config::internal::ValueConverter<T> >
+class VectorInserter : public ::vespalib::slime::ArrayTraverser {
+public:
+    VectorInserter(std::vector<T> & vector);
+    void entry(size_t idx, const ::vespalib::slime::Inspector & inspector);
+private:
+    std::vector<T> & _vector;
+};
+
+} // namespace internal
+
+} // namespace config
+
+#include "vector_inserter.hpp"
+
diff --git a/config/src/vespa/config/configgen/vector_inserter.hpp b/config/src/vespa/config/configgen/vector_inserter.hpp
new file mode 100644
index 00000000000..94c2b86ce65
--- /dev/null
+++ b/config/src/vespa/config/configgen/vector_inserter.hpp
@@ -0,0 +1,22 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+namespace config {
+
+namespace internal {
+
+template<typename T, typename Converter>
+VectorInserter<T, Converter>::VectorInserter(std::vector<T> & vector)
+    : _vector(vector)
+{}
+
+template<typename T, typename Converter>
+void
+VectorInserter<T, Converter>::entry(size_t idx, const ::vespalib::slime::Inspector & inspector)
+{
+    (void) idx;
+    Converter converter;
+    _vector.push_back(converter(inspector));
+}
+
+} // namespace internal
+
+}
diff --git a/config/src/vespa/config/file/.gitignore b/config/src/vespa/config/file/.gitignore
new file mode 100644
index 00000000000..7e7c0fe7fae
--- /dev/null
+++ b/config/src/vespa/config/file/.gitignore
@@ -0,0 +1,2 @@
+/.depend
+/Makefile
diff --git a/config/src/vespa/config/file/CMakeLists.txt b/config/src/vespa/config/file/CMakeLists.txt
new file mode 100644
index 00000000000..743e9ac5e74
--- /dev/null
+++ b/config/src/vespa/config/file/CMakeLists.txt
@@ -0,0 +1,7 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_library(config_file OBJECT
+    SOURCES
+    filesource.cpp
+    filesourcefactory.cpp
+    DEPENDS
+)
diff --git a/config/src/vespa/config/file/filesource.cpp b/config/src/vespa/config/file/filesource.cpp
new file mode 100644
index 00000000000..e2ee7248943
--- /dev/null
+++ b/config/src/vespa/config/file/filesource.cpp
@@ -0,0 +1,65 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.file.filesource");
+#include "filesource.h"
+#include <vespa/config/subscription/sourcespec.h>
+#include <vespa/config/common/misc.h>
+#include <vespa/vespalib/io/fileutil.h>
+#include <vespa/vespalib/stllike/asciistream.h>
+
+using vespalib::asciistream;
+
+namespace config {
+
+FileSource::FileSource(const IConfigHolder::SP & holder, const vespalib::string & fileName)
+    : _holder(holder),
+      _fileName(fileName),
+      _lastLoaded(-1),
+      _generation(1)
+{
+}
+
+void
+FileSource::getConfig()
+{
+    std::vector<vespalib::string> lines(readConfigFile(_fileName));
+    int64_t last = getLast(_fileName);
+
+    if (last > _lastLoaded) {
+        _holder->handle(ConfigUpdate::UP(new ConfigUpdate(ConfigValue(lines, calculateContentMd5(lines)), true, _generation)));
+        _lastLoaded = last;
+    } else {
+        _holder->handle(ConfigUpdate::UP(new ConfigUpdate(ConfigValue(lines, calculateContentMd5(lines)), false, _generation)));
+    }
+}
+
+void
+FileSource::reload(int64_t generation)
+{
+    _generation = generation;
+}
+
+int64_t
+FileSource::getLast(const vespalib::string & fileName)
+{
+    struct stat filestat;
+    memset(&filestat, 0, sizeof(filestat));
+    stat(fileName.c_str(), &filestat);
+    return filestat.st_mtime;
+}
+
+std::vector<vespalib::string>
+FileSource::readConfigFile(const vespalib::string & fileName)
+{
+    asciistream is(asciistream::createFromFile(fileName));
+    return is.getlines();
+}
+
+void
+FileSource::close()
+{
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/file/filesource.h b/config/src/vespa/config/file/filesource.h
new file mode 100644
index 00000000000..141d14faf5c
--- /dev/null
+++ b/config/src/vespa/config/file/filesource.h
@@ -0,0 +1,38 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <string>
+#include <vector>
+#include <map>
+#include <stack>
+#include <vespa/config/common/source.h>
+#include <vespa/config/common/iconfigholder.h>
+#include <vespa/vespalib/stllike/string.h>
+#include <vespa/vespalib/util/noncopyable.hpp>
+
+namespace config {
+
+class FileSpec;
+class DirSpec;
+
+class FileSource : public Source,
+                   public vespalib::noncopyable
+{
+private:
+    IConfigHolder::SP _holder;
+    const vespalib::string _fileName;
+    int64_t _lastLoaded;
+    int64_t _generation;
+
+    std::vector<vespalib::string> readConfigFile(const vespalib::string & fileName);
+    int64_t getLast(const vespalib::string & fileName);
+
+public:
+    FileSource(const IConfigHolder::SP & holder, const vespalib::string & fileName);
+    void getConfig();
+    void close();
+    void reload(int64_t generation);
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/file/filesourcefactory.cpp b/config/src/vespa/config/file/filesourcefactory.cpp
new file mode 100644
index 00000000000..ee827617368
--- /dev/null
+++ b/config/src/vespa/config/file/filesourcefactory.cpp
@@ -0,0 +1,64 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include "filesourcefactory.h"
+#include "filesource.h"
+#include <vespa/config/common/exceptions.h>
+#include <vespa/config/subscription/sourcespec.h>
+#include <vespa/vespalib/io/fileutil.h>
+#include <vespa/vespalib/stllike/asciistream.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.filesourcefactory");
+
+namespace config {
+
+DirSourceFactory::DirSourceFactory(const DirSpec & dirSpec)
+    : _dirName(dirSpec.getDirName()),
+      _fileNames()
+{
+    vespalib::DirectoryList files(vespalib::listDirectory(_dirName));
+    for (size_t i = 0; i < files.size(); i++) {
+        const vespalib::DirectoryList::value_type & fname(files[i]);
+        if (fname.length() > 4 && fname.substr(fname.length() - 4) == ".cfg") {
+            _fileNames.push_back(fname);
+        }
+    }
+}
+
+Source::UP
+DirSourceFactory::createSource(const IConfigHolder::SP & holder, const ConfigKey & key) const
+{
+    vespalib::string fileId(key.getDefName());
+    if (!key.getConfigId().empty()) {
+        fileId += "." + key.getConfigId();
+    }
+    fileId += ".cfg";
+
+    bool found(false);
+    for (const auto & fileName : _fileNames) {
+        if (fileName.compare(fileId) == 0) {
+            found = true;
+            break;
+        } 
+    }
+    if ( !found ) {
+        LOG(warning, "Filename '%s' was expected in the spec, but does not exist.", fileId.c_str());
+    }
+    vespalib::string fName = _dirName;
+    if (!fName.empty()) fName += "/";
+    fName += fileId;
+    return Source::UP(new FileSource(holder, fName));
+}
+
+FileSourceFactory::FileSourceFactory(const FileSpec & fileSpec)
+    : _fileName(fileSpec.getFileName())
+{
+}
+
+Source::UP
+FileSourceFactory::createSource(const IConfigHolder::SP & holder, const ConfigKey & key) const
+{
+    (void) key;
+    return Source::UP(new FileSource(holder, _fileName));
+}
+
+} // namespace config
+
diff --git a/config/src/vespa/config/file/filesourcefactory.h b/config/src/vespa/config/file/filesourcefactory.h
new file mode 100644
index 00000000000..c38b00aa034
--- /dev/null
+++ b/config/src/vespa/config/file/filesourcefactory.h
@@ -0,0 +1,48 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/sourcefactory.h>
+#include <vespa/vespalib/stllike/string.h>
+
+
+namespace config {
+
+class DirSpec;
+class FileSpec;
+
+/**
+ * Factory creating config payload from config instances.
+ */
+class FileSourceFactory : public SourceFactory
+{
+public:
+    FileSourceFactory(const FileSpec & fileSpec);
+
+    /**
+     * Create source handling config described by key.
+     */
+    Source::UP createSource(const IConfigHolder::SP & holder, const ConfigKey & key) const;
+private:
+    vespalib::string _fileName;
+};
+
+/**
+ * Factory creating config payload from config instances.
+ */
+class DirSourceFactory : public SourceFactory
+{
+public:
+    DirSourceFactory(const DirSpec & dirSpec);
+
+    /**
+     * Create source handling config described by key.
+     */
+    Source::UP createSource(const IConfigHolder::SP & holder, const ConfigKey & key) const;
+private:
+    vespalib::string _dirName;
+    std::vector<vespalib::string> _fileNames;
+};
+
+
+} // namespace config
+
diff --git a/config/src/vespa/config/frt/.gitignore b/config/src/vespa/config/frt/.gitignore
new file mode 100644
index 00000000000..7e7c0fe7fae
--- /dev/null
+++ b/config/src/vespa/config/frt/.gitignore
@@ -0,0 +1,2 @@
+/.depend
+/Makefile
diff --git a/config/src/vespa/config/frt/CMakeLists.txt b/config/src/vespa/config/frt/CMakeLists.txt
new file mode 100644
index 00000000000..fcc8abfa1b8
--- /dev/null
+++ b/config/src/vespa/config/frt/CMakeLists.txt
@@ -0,0 +1,21 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_library(config_frt OBJECT
+    SOURCES
+    frtsource.cpp
+    frtconnectionpool.cpp
+    frtconnection.cpp
+    frtconfigrequest.cpp
+    frtconfigresponse.cpp
+    frtsourcefactory.cpp
+    frtconfigagent.cpp
+    frtconfigrequestv2.cpp
+    frtconfigrequestfactory.cpp
+    frtconfigresponsev2.cpp
+    protocol.cpp
+    slimeconfigrequest.cpp
+    slimeconfigresponse.cpp
+    frtconfigrequestv3.cpp
+    frtconfigresponsev3.cpp
+    compressioninfo.cpp
+    DEPENDS
+)
diff --git a/config/src/vespa/config/frt/compressioninfo.cpp b/config/src/vespa/config/frt/compressioninfo.cpp
new file mode 100644
index 00000000000..270d335b7ae
--- /dev/null
+++ b/config/src/vespa/config/frt/compressioninfo.cpp
@@ -0,0 +1,24 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/config/frt/protocol.h>
+#include "compressioninfo.h"
+
+using namespace vespalib;
+using namespace vespalib::slime;
+using namespace config::protocol;
+
+namespace config {
+
+CompressionInfo::CompressionInfo()
+    : compressionType(CompressionType::UNCOMPRESSED),
+      uncompressedSize(0)
+{
+}
+
+void
+CompressionInfo::deserialize(const Inspector & inspector)
+{
+    compressionType = stringToCompressionType(inspector["compressionType"].asString().make_string());
+    uncompressedSize = inspector["uncompressedSize"].asLong();
+}
+
+}
diff --git a/config/src/vespa/config/frt/compressioninfo.h b/config/src/vespa/config/frt/compressioninfo.h
new file mode 100644
index 00000000000..2ba5d5c52c7
--- /dev/null
+++ b/config/src/vespa/config/frt/compressioninfo.h
@@ -0,0 +1,16 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/frt/protocol.h>
+
+namespace config {
+
+struct CompressionInfo {
+    CompressionInfo();
+    CompressionType compressionType;
+    uint32_t uncompressedSize;
+    void deserialize(const vespalib::slime::Inspector & inspector);
+};
+
+}
+
diff --git a/config/src/vespa/config/frt/connection.h b/config/src/vespa/config/frt/connection.h
new file mode 100644
index 00000000000..7bd8229411f
--- /dev/null
+++ b/config/src/vespa/config/frt/connection.h
@@ -0,0 +1,20 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+class FRT_RPCRequest;
+class FRT_IRequestWait;
+
+namespace config {
+
+class Connection {
+public:
+    virtual FRT_RPCRequest * allocRPCRequest() = 0;
+    virtual void setError(int errorCode) = 0;
+    virtual void invoke(FRT_RPCRequest * req, double timeout, FRT_IRequestWait * waiter) = 0;
+    virtual const vespalib::string & getAddress() const = 0;
+    virtual void setTransientDelay(int64_t delay) = 0;
+    virtual ~Connection() { }
+};
+
+}
+
diff --git a/config/src/vespa/config/frt/connectionfactory.h b/config/src/vespa/config/frt/connectionfactory.h
new file mode 100644
index 00000000000..c2c5bfe0c96
--- /dev/null
+++ b/config/src/vespa/config/frt/connectionfactory.h
@@ -0,0 +1,23 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+
+class FNET_Scheduler;
+
+namespace config {
+
+class Connection;
+
+class ConnectionFactory
+{
+public:
+    typedef std::unique_ptr <ConnectionFactory> UP;
+    typedef std::shared_ptr<ConnectionFactory> SP;
+    virtual Connection * getCurrent() = 0;
+    virtual void syncTransport() = 0;
+    virtual FNET_Scheduler * getScheduler() = 0;
+    virtual ~ConnectionFactory() { }
+};
+
+}
+
diff --git a/config/src/vespa/config/frt/frtconfigagent.cpp b/config/src/vespa/config/frt/frtconfigagent.cpp
new file mode 100644
index 00000000000..397067b85a1
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigagent.cpp
@@ -0,0 +1,102 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.frt.frtconfigagent");
+#include "frtconfigagent.h"
+#include <vespa/config/common/trace.h>
+#include <vespa/config/common/configrequest.h>
+#include <vespa/config/common/configkey.h>
+
+namespace config {
+
+FRTConfigAgent::FRTConfigAgent(const IConfigHolder::SP & holder, const TimingValues & timingValues)
+    : _holder(holder),
+      _timingValues(timingValues),
+      _configState(),
+      _latest(),
+      _waitTime(0),
+      _numConfigured(0),
+      _failedRequests(0),
+      _nextTimeout(_timingValues.initialTimeout)
+{
+}
+
+void
+FRTConfigAgent::handleResponse(const ConfigRequest & request, ConfigResponse::UP response)
+{
+    if (LOG_WOULD_LOG(spam)) {
+        const ConfigKey & key(request.getKey());
+        LOG(spam, "current state for %s: generation %" PRId64 " md5 %s", key.toString().c_str(), _configState.generation, _configState.md5.c_str());
+    }
+    if (response->validateResponse() && !response->isError()) {
+        handleOKResponse(std::move(response));
+    } else {
+        handleErrorResponse(request, std::move(response));
+    }
+}
+
+void
+FRTConfigAgent::handleOKResponse(ConfigResponse::UP response)
+{
+    _failedRequests = 0;
+    response->fill();
+    if (LOG_WOULD_LOG(spam)) {
+        LOG(spam, "trace(%s)", response->getTrace().toString().c_str());
+    }
+
+    ConfigState newState = response->getConfigState();
+    bool isNewGeneration = newState.isNewerGenerationThan(_configState);
+    if (isNewGeneration) {
+        handleUpdatedGeneration(response->getKey(), newState, response->getValue());
+    }
+    setWaitTime(_timingValues.successDelay, 1);
+    _nextTimeout = _timingValues.successTimeout;
+}
+
+void
+FRTConfigAgent::handleUpdatedGeneration(const ConfigKey & key, const ConfigState & newState, const ConfigValue & configValue)
+{
+    if (LOG_WOULD_LOG(spam)) {
+        LOG(spam, "new generation %" PRId64 " for key %s", newState.generation, key.toString().c_str());
+    }
+    _configState.generation = newState.generation;
+    bool hasDifferentPayload = newState.hasDifferentPayloadFrom(_configState);
+    if (hasDifferentPayload) {
+        if (LOG_WOULD_LOG(spam)) {
+            LOG(spam, "new payload for key %s, existing md5(%s), new md5(%s)", key.toString().c_str(), _configState.md5.c_str(), newState.md5.c_str());
+        }
+        _configState.md5 = newState.md5;
+        _latest = configValue;
+    }
+
+    if (LOG_WOULD_LOG(spam)) {
+        LOG(spam, "updating holder for key %s, payload changed: %d", key.toString().c_str(), hasDifferentPayload ? 1 : 0);
+    }
+    _holder->handle(ConfigUpdate::UP(new ConfigUpdate(_latest, hasDifferentPayload, _configState.generation)));
+    _numConfigured++;
+}
+
+void
+FRTConfigAgent::handleErrorResponse(const ConfigRequest & request, ConfigResponse::UP response)
+{
+    _failedRequests++;
+    int multiplier = std::min(_failedRequests, _timingValues.maxDelayMultiplier);
+    setWaitTime(_numConfigured > 0 ? _timingValues.configuredErrorDelay : _timingValues.unconfiguredDelay, multiplier);
+    _nextTimeout = _timingValues.errorTimeout;
+    const ConfigKey & key(request.getKey());
+    LOG(info, "Error response or no response from config server (key: %s) (errcode=%d, validresponse:%d), trying again in %" PRId64 " milliseconds", key.toString().c_str(), response->errorCode(), response->hasValidResponse() ? 1 : 0, _waitTime);
+}
+
+void
+FRTConfigAgent::setWaitTime(uint64_t delay, int multiplier)
+{
+    uint64_t prevWait = _waitTime;
+    _waitTime = _timingValues.fixedDelay + (multiplier * delay);
+    LOG(spam, "Adjusting waittime from %" PRId64 " to %" PRId64, prevWait, _waitTime);
+}
+
+uint64_t FRTConfigAgent::getTimeout() const { return _nextTimeout; }
+uint64_t FRTConfigAgent::getWaitTime() const { return _waitTime; }
+const ConfigState & FRTConfigAgent::getConfigState() const { return _configState; }
+
+}
diff --git a/config/src/vespa/config/frt/frtconfigagent.h b/config/src/vespa/config/frt/frtconfigagent.h
new file mode 100644
index 00000000000..b058d184ea0
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigagent.h
@@ -0,0 +1,50 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/configstate.h>
+#include <vespa/config/common/timingvalues.h>
+#include <vespa/config/common/iconfigholder.h>
+#include <vespa/config/common/configresponse.h>
+#include <vespa/config/common/configrequest.h>
+
+namespace config {
+
+class ConfigAgent
+{
+public:
+    typedef std::unique_ptr<ConfigAgent> UP;
+    virtual void handleResponse(const ConfigRequest & request, ConfigResponse::UP response) = 0;
+
+    virtual uint64_t getTimeout() const = 0;
+    virtual uint64_t getWaitTime() const = 0;
+    virtual const ConfigState & getConfigState() const = 0;
+
+    virtual ~ConfigAgent() { }
+};
+
+class FRTConfigAgent : public ConfigAgent
+{
+public:
+    FRTConfigAgent(const IConfigHolder::SP & holder, const TimingValues & timingValues);
+    void handleResponse(const ConfigRequest & request, ConfigResponse::UP response);
+    uint64_t getTimeout() const;
+    uint64_t getWaitTime() const;
+    const ConfigState & getConfigState() const;
+private:
+    void handleUpdatedGeneration(const ConfigKey & key, const ConfigState & newState, const ConfigValue & configValue);
+    void handleOKResponse(ConfigResponse::UP response);
+    void handleErrorResponse(const ConfigRequest & request, ConfigResponse::UP response);
+    void setWaitTime(uint64_t delay, int multiplier);
+
+    IConfigHolder::SP _holder;
+    const TimingValues _timingValues;
+    ConfigState _configState;
+    ConfigValue _latest;
+    uint64_t _waitTime;
+    uint64_t _numConfigured;
+    unsigned int _failedRequests;
+    uint64_t _nextTimeout;
+};
+
+}
+
diff --git a/config/src/vespa/config/frt/frtconfigrequest.cpp b/config/src/vespa/config/frt/frtconfigrequest.cpp
new file mode 100644
index 00000000000..0a8088a191a
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigrequest.cpp
@@ -0,0 +1,99 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.frt.frtconfigrequest");
+#include "frtconfigrequest.h"
+#include "frtconfigresponse.h"
+#include "connection.h"
+#include <vespa/fnet/frt/frt.h>
+#include <vespa/config/common/configkey.h>
+#include <vespa/config/common/configstate.h>
+
+namespace config {
+
+FRTConfigRequest::FRTConfigRequest(Connection * connection, const ConfigKey & key)
+    : _request(connection->allocRPCRequest()),
+      _parameters(*_request->GetParams()),
+      _connection(connection),
+      _key(key)
+{
+}
+
+FRTConfigRequest::~FRTConfigRequest()
+{
+    _request->SubRef();
+}
+
+bool
+FRTConfigRequest::abort()
+{
+    return _request->Abort();
+}
+
+void
+FRTConfigRequest::setError(int errorCode)
+{
+    _connection->setError(errorCode);
+}
+
+const ConfigKey &
+FRTConfigRequest::getKey() const
+{
+    return _key;
+}
+
+bool
+FRTConfigRequest::isAborted() const
+{
+    return (_request->GetErrorCode() == FRTE_RPC_ABORT);
+}
+
+const vespalib::string FRTConfigRequestV1::REQUEST_TYPES = "sssssllsSi";
+
+FRTConfigRequestV1::FRTConfigRequestV1(const ConfigKey & key,
+                                       Connection * connection,
+                                       const vespalib::string & configMd5,
+                                       int64_t generation,
+                                       int64_t serverTimeout)
+    : FRTConfigRequest(connection, key)
+{
+    _request->SetMethodName("config.v1.getConfig");
+    _parameters.AddString(key.getDefName().c_str());
+    _parameters.AddString("");
+    _parameters.AddString(key.getDefMd5().c_str());
+    _parameters.AddString(key.getConfigId().c_str());
+    _parameters.AddString(configMd5.c_str());
+    _parameters.AddInt64(generation);
+    _parameters.AddInt64(serverTimeout);
+    _parameters.AddString(key.getDefNamespace().c_str());
+    const std::vector<vespalib::string> & schema(key.getDefSchema());
+    FRT_StringValue * schemaValue = _parameters.AddStringArray(schema.size());
+    for (size_t i = 0; i < schema.size(); i++) {
+        _parameters.SetString(&schemaValue[i], schema[i].c_str());
+    }
+    _parameters.AddInt32(1);
+}
+
+bool
+FRTConfigRequestV1::verifyKey(const ConfigKey & key) const
+{
+    return (key.getDefName().compare(_parameters[0]._string._str) == 0 &&
+            key.getDefNamespace().compare(_parameters[7]._string._str) == 0 &&
+            key.getConfigId().compare(_parameters[3]._string._str) == 0 &&
+            key.getDefMd5().compare(_parameters[2]._string._str) == 0);
+}
+
+bool
+FRTConfigRequestV1::verifyState(const ConfigState & state) const
+{
+    return (state.md5.compare(_parameters[4]._string._str) == 0 &&
+            state.generation == static_cast<int64_t>(_parameters[5]._intval64));
+}
+
+ConfigResponse::UP
+FRTConfigRequestV1::createResponse(FRT_RPCRequest * request) const
+{
+    return ConfigResponse::UP(new FRTConfigResponseV1(request));
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/frt/frtconfigrequest.h b/config/src/vespa/config/frt/frtconfigrequest.h
new file mode 100644
index 00000000000..ac7f66ffba9
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigrequest.h
@@ -0,0 +1,58 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/configrequest.h>
+#include <vespa/config/common/configresponse.h>
+#include <vespa/config/common/configkey.h>
+#include <vespa/vespalib/stllike/string.h>
+
+class FRT_Values;
+class FRT_RPCRequest;
+
+namespace config {
+
+class ConfigKey;
+class Connection;
+
+/**
+ * Class representing a FRT config request.
+ */
+class FRTConfigRequest : public ConfigRequest {
+public:
+    typedef std::unique_ptr<FRTConfigRequest> UP;
+    FRTConfigRequest(Connection * connection, const ConfigKey & key);
+    virtual ~FRTConfigRequest();
+    virtual bool verifyKey(const ConfigKey & key) const = 0;
+    virtual bool verifyState(const ConfigState & state) const = 0;
+
+    bool abort();
+    bool isAborted() const;
+    void setError(int errorCode);
+    const ConfigKey & getKey() const;
+
+    FRT_RPCRequest* getRequest() { return _request; }
+    virtual ConfigResponse::UP createResponse(FRT_RPCRequest * request) const = 0;
+protected:
+    FRT_RPCRequest *_request;
+    FRT_Values & _parameters;
+private:
+    Connection * _connection;
+    const ConfigKey _key;
+};
+
+class FRTConfigRequestV1 : public FRTConfigRequest {
+public:
+    FRTConfigRequestV1(const ConfigKey & key,
+                     Connection * connection,
+                     const vespalib::string & configMd5,
+                     int64_t generation,
+                     int64_t serverTimeout);
+    bool verifyKey(const ConfigKey & key) const;
+    bool verifyState(const ConfigState & state) const;
+    ConfigResponse::UP createResponse(FRT_RPCRequest * request) const;
+private:
+    static const vespalib::string REQUEST_TYPES;
+};
+
+}
+
diff --git a/config/src/vespa/config/frt/frtconfigrequestfactory.cpp b/config/src/vespa/config/frt/frtconfigrequestfactory.cpp
new file mode 100644
index 00000000000..7565d99a8aa
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigrequestfactory.cpp
@@ -0,0 +1,38 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include "frtconfigrequestfactory.h"
+#include "frtconfigrequest.h"
+#include "frtconfigrequestv2.h"
+#include "frtconfigrequestv3.h"
+#include <vespa/config/common/trace.h>
+#include <vespa/config/common/compressiontype.h>
+#include <vespa/vespalib/util/host_name.h>
+#include <unistd.h>
+#include <limits.h>
+
+
+namespace config {
+
+/**
+ * Factory for creating config requests depending on protocol version;
+ */
+FRTConfigRequestFactory::FRTConfigRequestFactory(int protocolVersion, int traceLevel, const VespaVersion & vespaVersion, const CompressionType & compressionType)
+    : _protocolVersion(protocolVersion),
+      _traceLevel(traceLevel),
+      _vespaVersion(vespaVersion),
+      _hostName(vespalib::HostName::get()),
+      _compressionType(compressionType)
+{
+}
+
+FRTConfigRequest::UP
+FRTConfigRequestFactory::createConfigRequest(const ConfigKey & key, Connection * connection, const ConfigState & state, int64_t serverTimeout) const
+{
+    if (1 == _protocolVersion) {
+        return FRTConfigRequest::UP(new FRTConfigRequestV1(key, connection, state.md5, state.generation, serverTimeout));
+    } else if (2 == _protocolVersion) {
+        return FRTConfigRequest::UP(new FRTConfigRequestV2(connection, key, state.md5, state.generation, 0u, _hostName, serverTimeout, Trace(_traceLevel)));
+    }
+    return FRTConfigRequest::UP(new FRTConfigRequestV3(connection, key, state.md5, state.generation, 0u, _hostName, serverTimeout, Trace(_traceLevel), _vespaVersion, _compressionType));
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/frt/frtconfigrequestfactory.h b/config/src/vespa/config/frt/frtconfigrequestfactory.h
new file mode 100644
index 00000000000..98d7175a352
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigrequestfactory.h
@@ -0,0 +1,32 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/configkey.h>
+#include <vespa/config/common/configstate.h>
+#include <vespa/config/common/trace.h>
+#include <vespa/config/common/compressiontype.h>
+#include <vespa/config/common/vespa_version.h>
+#include "frtconfigrequest.h"
+#include "protocol.h"
+#include "connection.h"
+
+namespace config {
+
+/**
+ * Factory for creating config requests depending on protocol version;
+ */
+class FRTConfigRequestFactory
+{
+public:
+    FRTConfigRequestFactory(int protocolVersion, int traceLevel, const VespaVersion & vespaVersion, const CompressionType & compressionType);
+    FRTConfigRequest::UP createConfigRequest(const ConfigKey & key, Connection * connection, const ConfigState & state, int64_t serverTimeout) const;
+private:
+    const int _protocolVersion;
+    const int _traceLevel;
+    const VespaVersion _vespaVersion;
+    vespalib::string _hostName;
+    const CompressionType _compressionType;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/frt/frtconfigrequestv2.cpp b/config/src/vespa/config/frt/frtconfigrequestv2.cpp
new file mode 100644
index 00000000000..97335468a97
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigrequestv2.cpp
@@ -0,0 +1,35 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.frt.frtconfigrequestv2");
+#include "frtconfigrequestv2.h"
+#include "frtconfigresponsev2.h"
+#include "connection.h"
+#include <vespa/config/common/trace.h>
+#include <vespa/config/common/vespa_version.h>
+
+using namespace config::protocol;
+
+namespace config {
+
+FRTConfigRequestV2::FRTConfigRequestV2(Connection * connection,
+                                       const ConfigKey & key,
+                                       const vespalib::string & configMd5,
+                                       int64_t currentGeneration,
+                                       int64_t wantedGeneration,
+                                       const vespalib::string & hostName,
+                                       int64_t serverTimeout,
+                                       const Trace & trace)
+    : SlimeConfigRequest(connection, key, configMd5, currentGeneration, wantedGeneration, hostName, serverTimeout, trace, VespaVersion::getCurrentVersion(), 2, CompressionType::UNCOMPRESSED, "config.v2.getConfig")
+{
+}
+
+
+
+ConfigResponse::UP
+FRTConfigRequestV2::createResponse(FRT_RPCRequest * request) const
+{
+    return ConfigResponse::UP(new FRTConfigResponseV2(request));
+}
+
+}
diff --git a/config/src/vespa/config/frt/frtconfigrequestv2.h b/config/src/vespa/config/frt/frtconfigrequestv2.h
new file mode 100644
index 00000000000..d3ed95a26c3
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigrequestv2.h
@@ -0,0 +1,29 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "slimeconfigrequest.h"
+
+class FRT_Values;
+class FRT_RPCRequest;
+
+namespace config {
+
+class ConfigKey;
+class Connection;
+class Trace;
+
+class FRTConfigRequestV2 : public SlimeConfigRequest {
+public:
+    FRTConfigRequestV2(Connection * connection,
+                       const ConfigKey & key,
+                       const vespalib::string & configMd5,
+                       int64_t currentGeneration,
+                       int64_t wantedGeneration,
+                       const vespalib::string & hostName,
+                       int64_t serverTimeout,
+                       const Trace & trace);
+    ConfigResponse::UP createResponse(FRT_RPCRequest * request) const;
+};
+
+}
+
diff --git a/config/src/vespa/config/frt/frtconfigrequestv3.cpp b/config/src/vespa/config/frt/frtconfigrequestv3.cpp
new file mode 100644
index 00000000000..11a3496348f
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigrequestv3.cpp
@@ -0,0 +1,37 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.frt.frtconfigrequestv3");
+#include "frtconfigrequestv3.h"
+#include "frtconfigresponsev3.h"
+#include "connection.h"
+#include <vespa/config/common/trace.h>
+#include <vespa/config/common/vespa_version.h>
+
+using namespace config::protocol;
+
+namespace config {
+
+FRTConfigRequestV3::FRTConfigRequestV3(Connection * connection,
+                                       const ConfigKey & key,
+                                       const vespalib::string & configMd5,
+                                       int64_t currentGeneration,
+                                       int64_t wantedGeneration,
+                                       const vespalib::string & hostName,
+                                       int64_t serverTimeout,
+                                       const Trace & trace,
+                                       const VespaVersion & vespaVersion,
+                                       const CompressionType & compressionType)
+    : SlimeConfigRequest(connection, key, configMd5, currentGeneration, wantedGeneration, hostName, serverTimeout, trace, vespaVersion, 3, compressionType, "config.v3.getConfig")
+{
+}
+
+
+
+ConfigResponse::UP
+FRTConfigRequestV3::createResponse(FRT_RPCRequest * request) const
+{
+    return ConfigResponse::UP(new FRTConfigResponseV3(request));
+}
+
+}
diff --git a/config/src/vespa/config/frt/frtconfigrequestv3.h b/config/src/vespa/config/frt/frtconfigrequestv3.h
new file mode 100644
index 00000000000..a8f9580f232
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigrequestv3.h
@@ -0,0 +1,32 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "slimeconfigrequest.h"
+
+class FRT_Values;
+class FRT_RPCRequest;
+
+namespace config {
+
+class ConfigKey;
+class Connection;
+class Trace;
+class VespaVersion;
+
+class FRTConfigRequestV3 : public SlimeConfigRequest {
+public:
+    FRTConfigRequestV3(Connection * connection,
+                       const ConfigKey & key,
+                       const vespalib::string & configMd5,
+                       int64_t currentGeneration,
+                       int64_t wantedGeneration,
+                       const vespalib::string & hostName,
+                       int64_t serverTimeout,
+                       const Trace & trace,
+                       const VespaVersion & vespaVersion,
+                       const CompressionType & compressionType);
+    ConfigResponse::UP createResponse(FRT_RPCRequest * request) const;
+};
+
+}
+
diff --git a/config/src/vespa/config/frt/frtconfigresponse.cpp b/config/src/vespa/config/frt/frtconfigresponse.cpp
new file mode 100644
index 00000000000..d815525cb40
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigresponse.cpp
@@ -0,0 +1,98 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.frt.frtconfigresponse");
+#include "frtconfigresponse.h"
+#include <vespa/config/common/misc.h>
+#include <vespa/fnet/frt/frt.h>
+#include <vespa/vespalib/stllike/string.h>
+
+namespace config {
+
+FRTConfigResponse::FRTConfigResponse(FRT_RPCRequest * request)
+    : _request(request),
+      _responseState(EMPTY),
+      _returnValues(_request->GetReturn())
+{
+    _request->AddRef();
+}
+
+FRTConfigResponse::~FRTConfigResponse()
+{
+    _request->SubRef();
+}
+
+bool
+FRTConfigResponse::validateResponse()
+{
+    if (_request->IsError())
+        _responseState = ERROR;
+    if (_request->GetReturn()->GetNumValues() == 0)
+        _responseState = EMPTY;
+    if (_request->CheckReturnTypes(getResponseTypes().c_str())) {
+        _returnValues = _request->GetReturn();
+        _responseState = OK;
+    }
+    return (_responseState == OK);
+}
+
+bool
+FRTConfigResponse::hasValidResponse() const
+{
+    return (_responseState == OK);
+}
+
+vespalib::string FRTConfigResponse::errorMessage() const { return _request->GetErrorMessage(); }
+int FRTConfigResponse::errorCode() const { return _request->GetErrorCode(); }
+bool FRTConfigResponse::isError() const { return _request->IsError(); }
+
+//
+// V1 Implementation
+//
+const vespalib::string FRTConfigResponseV1::RESPONSE_TYPES = "sssssilSs";
+
+FRTConfigResponseV1::FRTConfigResponseV1(FRT_RPCRequest * request)
+    : FRTConfigResponse(request),
+      _key(),
+      _value()
+{
+}
+
+const vespalib::string &
+FRTConfigResponseV1::getResponseTypes() const
+{
+    return RESPONSE_TYPES;
+}
+
+void
+FRTConfigResponseV1::fill()
+{
+    const std::vector<vespalib::string> payload(getPayLoad());
+    for (size_t i = 0; i < payload.size(); i++) {
+        LOG(spam, "payload(%lu): %s", i, payload[i].c_str());
+    }
+    _value = ConfigValue(payload, calculateContentMd5(payload));
+    _key = readKey();
+    _state = ConfigState(vespalib::string((*_returnValues)[4]._string._str), (*_returnValues)[6]._intval64);
+}
+
+const ConfigKey
+FRTConfigResponseV1::readKey() const
+{
+    return ConfigKey((*_returnValues)[3]._string._str, (*_returnValues)[0]._string._str, (*_returnValues)[8]._string._str, (*_returnValues)[2]._string._str);
+}
+
+const std::vector<vespalib::string>
+FRTConfigResponseV1::getPayLoad() const
+{
+    uint32_t numStrings = (*_returnValues)[7]._string_array._len;
+    FRT_StringValue *s = (*_returnValues)[7]._string_array._pt;
+    std::vector<vespalib::string> payload;
+    payload.reserve(numStrings);
+    for (uint32_t i = 0; i < numStrings; i++) {
+        payload.push_back(vespalib::string(s[i]._str));
+    }
+    return payload;
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/frt/frtconfigresponse.h b/config/src/vespa/config/frt/frtconfigresponse.h
new file mode 100644
index 00000000000..49a7bd8ba58
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigresponse.h
@@ -0,0 +1,70 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/configresponse.h>
+#include <vespa/config/common/configkey.h>
+#include <vespa/config/common/configvalue.h>
+#include <vespa/config/common/trace.h>
+#include <vespa/config/common/configstate.h>
+
+class FRT_RPCRequest;
+class FRT_Values;
+
+namespace config {
+
+/**
+ * Baseclass for config responses.
+ */
+class FRTConfigResponse : public ConfigResponse {
+private:
+    FRTConfigResponse& operator=(const FRTConfigResponse&);
+public:
+    typedef std::unique_ptr<FRTConfigResponse> UP;
+    FRTConfigResponse(FRT_RPCRequest * request);
+    virtual ~FRTConfigResponse();
+
+    bool validateResponse();
+    bool hasValidResponse() const;
+    vespalib::string errorMessage() const;
+    int errorCode() const;
+    bool isError() const;
+    virtual const vespalib::string & getResponseTypes() const = 0;
+
+private:
+    enum ResponseState { EMPTY, OK, ERROR };
+
+    FRT_RPCRequest * _request;
+    ResponseState _responseState;
+protected:
+    FRT_Values * _returnValues;
+};
+
+class FRTConfigResponseV1 : public FRTConfigResponse {
+private:
+    FRTConfigResponseV1& operator=(const FRTConfigResponseV1&);
+public:
+    FRTConfigResponseV1(FRT_RPCRequest * request);
+
+    const ConfigKey & getKey() const { return _key; }
+    const ConfigValue & getValue() const { return _value; }
+    const Trace & getTrace() const { return _trace; }
+
+    const ConfigState & getConfigState() const { return _state; }
+
+    void fill();
+
+private:
+    static const vespalib::string RESPONSE_TYPES;
+
+    const std::vector<vespalib::string> getPayLoad() const;
+    const ConfigKey readKey() const;
+    const vespalib::string & getResponseTypes() const;
+
+    ConfigKey _key;
+    ConfigValue _value;
+    ConfigState _state;
+    Trace _trace;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/frt/frtconfigresponsev2.cpp b/config/src/vespa/config/frt/frtconfigresponsev2.cpp
new file mode 100644
index 00000000000..8de19b95145
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigresponsev2.cpp
@@ -0,0 +1,50 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.frt.frtconfigresponsev2");
+#include "frtconfigresponsev2.h"
+#include <vespa/config/common/misc.h>
+#include <vespa/fnet/frt/frt.h>
+#include <vespa/vespalib/stllike/string.h>
+
+using namespace vespalib;
+using namespace vespalib::slime;
+using namespace vespalib::slime::convenience;
+using namespace config::protocol::v2;
+
+namespace config {
+
+class V2Payload : public protocol::Payload {
+public:
+    V2Payload(const SlimePtr & data)
+        : _data(data)
+    {}
+    const Inspector & getSlimePayload() const
+    {
+        return extractPayload(*_data);
+    }
+private:
+    SlimePtr _data;
+};
+
+const vespalib::string FRTConfigResponseV2::RESPONSE_TYPES = "s";
+
+FRTConfigResponseV2::FRTConfigResponseV2(FRT_RPCRequest * request)
+    : SlimeConfigResponse(request)
+{
+}
+
+const vespalib::string &
+FRTConfigResponseV2::getResponseTypes() const
+{
+    return RESPONSE_TYPES;
+}
+
+const ConfigValue
+FRTConfigResponseV2::readConfigValue() const
+{
+    vespalib::string md5(_data->get()[RESPONSE_CONFIG_MD5].asString().make_string());
+    return ConfigValue(PayloadPtr(new V2Payload(_data)), md5);
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/frt/frtconfigresponsev2.h b/config/src/vespa/config/frt/frtconfigresponsev2.h
new file mode 100644
index 00000000000..ce370b3880d
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigresponsev2.h
@@ -0,0 +1,32 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "slimeconfigresponse.h"
+#include <vespa/config/common/configkey.h>
+#include <vespa/config/common/configvalue.h>
+#include <vespa/config/common/trace.h>
+#include <vespa/vespalib/data/slime/slime.h>
+#include "protocol.h"
+
+class FRT_RPCRequest;
+class FRT_Values;
+
+namespace config {
+
+/**
+ * Baseclass for config responses.
+ */
+class FRTConfigResponseV2 : public SlimeConfigResponse {
+private:
+    FRTConfigResponseV2& operator=(const FRTConfigResponseV2&);
+public:
+    FRTConfigResponseV2(FRT_RPCRequest * request);
+
+private:
+    static const vespalib::string RESPONSE_TYPES;
+    const vespalib::string & getResponseTypes() const;
+    const ConfigValue readConfigValue() const;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/frt/frtconfigresponsev3.cpp b/config/src/vespa/config/frt/frtconfigresponsev3.cpp
new file mode 100644
index 00000000000..5421f0cb667
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigresponsev3.cpp
@@ -0,0 +1,76 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.frt.frtconfigresponsev3");
+#include "frtconfigresponsev3.h"
+#include "compressioninfo.h"
+#include <vespa/config/common/misc.h>
+#include <vespa/fnet/frt/frt.h>
+#include <vespa/vespalib/stllike/string.h>
+
+using namespace vespalib;
+using namespace vespalib::slime;
+using namespace vespalib::slime::convenience;
+using namespace config::protocol;
+using namespace config::protocol::v2;
+using namespace config::protocol::v3;
+
+namespace config {
+
+std::string make_json(const Slime &slime, bool compact) {
+    vespalib::slime::SimpleBuffer buf;
+    vespalib::slime::JsonFormat::encode(slime, buf, compact);
+    return buf.get().make_string();
+}
+
+class V3Payload : public Payload
+{
+public:
+    V3Payload(const SlimePtr & data)
+        : _data(data)
+    {
+    }
+
+    const Inspector & getSlimePayload() const
+    {
+        return _data->get();
+    }
+private:
+    SlimePtr _data;
+};
+
+const vespalib::string FRTConfigResponseV3::RESPONSE_TYPES = "sx";
+
+FRTConfigResponseV3::FRTConfigResponseV3(FRT_RPCRequest * request)
+    : SlimeConfigResponse(request)
+{
+}
+
+const vespalib::string &
+FRTConfigResponseV3::getResponseTypes() const
+{
+    return RESPONSE_TYPES;
+}
+
+const ConfigValue
+FRTConfigResponseV3::readConfigValue() const
+{
+    vespalib::string md5(_data->get()[RESPONSE_CONFIG_MD5].asString().make_string());
+    CompressionInfo info;
+    info.deserialize(_data->get()[RESPONSE_COMPRESSION_INFO]);
+    Slime * rawData = new Slime();
+    SlimePtr payloadData(rawData);
+    DecompressedData data(decompress(((*_returnValues)[1]._data._buf), ((*_returnValues)[1]._data._len), info.compressionType, info.uncompressedSize));
+    size_t consumedSize = JsonFormat::decode(data.memRef, *rawData);
+    if (consumedSize != data.size) {
+        std::string json(make_json(*payloadData, true));
+        LOG(error, "Error decoding JSON. Consumed size: %lu, uncompressed size: %u, compression type: %s, assumed uncompressed size(%u), compressed size: %u, slime(%s)", consumedSize, data.size, compressionTypeToString(info.compressionType).c_str(), info.uncompressedSize, ((*_returnValues)[1]._data._len), json.c_str());
+        assert(false);
+    }
+    if (LOG_WOULD_LOG(spam)) {
+        LOG(spam, "read config value md5(%s), payload size: %lu", md5.c_str(), data.memRef.size);
+    }
+    return ConfigValue(PayloadPtr(new V3Payload(payloadData)), md5);
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/frt/frtconfigresponsev3.h b/config/src/vespa/config/frt/frtconfigresponsev3.h
new file mode 100644
index 00000000000..e2b9b9e5286
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconfigresponsev3.h
@@ -0,0 +1,32 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "slimeconfigresponse.h"
+#include <vespa/config/common/configkey.h>
+#include <vespa/config/common/configvalue.h>
+#include <vespa/config/common/trace.h>
+#include <vespa/vespalib/data/slime/slime.h>
+#include "protocol.h"
+
+class FRT_RPCRequest;
+class FRT_Values;
+
+namespace config {
+
+/**
+ * Baseclass for config responses.
+ */
+class FRTConfigResponseV3 : public SlimeConfigResponse {
+private:
+    FRTConfigResponseV3& operator=(const FRTConfigResponseV3&);
+public:
+    FRTConfigResponseV3(FRT_RPCRequest * request);
+
+private:
+    static const vespalib::string RESPONSE_TYPES;
+    const vespalib::string & getResponseTypes() const;
+    const ConfigValue readConfigValue() const;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/frt/frtconnection.cpp b/config/src/vespa/config/frt/frtconnection.cpp
new file mode 100644
index 00000000000..13e37f71b42
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconnection.cpp
@@ -0,0 +1,118 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <time.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.frt.frtconnection");
+#include <vespa/vespalib/util/atomic.h>
+#include <vespa/config/common/errorcode.h>
+#include "frtconnection.h"
+
+using namespace vespalib;
+
+namespace config {
+
+FRTConnection::FRTConnection(const vespalib::string& address, FRT_Supervisor& supervisor, const TimingValues & timingValues)
+    : _address(address),
+      _supervisor(supervisor),
+      _target(0),
+      _suspendedUntil(0),
+      _suspendWarned(0),
+      _transientFailures(0),
+      _fatalFailures(0),
+      _transientDelay(timingValues.transientDelay),
+      _fatalDelay(timingValues.fatalDelay)
+{
+}
+
+FRTConnection::~FRTConnection()
+{
+    if (_target != NULL) {
+        _target->SubRef();
+        _target = NULL;
+    }
+}
+
+FRT_Target *
+FRTConnection::getTarget()
+{
+    if (_target == NULL) {
+        _target = _supervisor.GetTarget(_address.c_str());
+    } else if ( ! _target->IsValid()) {
+        _target->SubRef();
+        _target = _supervisor.GetTarget(_address.c_str());
+    }
+    return _target;
+}
+
+void
+FRTConnection::invoke(FRT_RPCRequest * req, double timeout, FRT_IRequestWait * waiter)
+{
+    getTarget()->InvokeAsync(req, timeout, waiter);
+}
+
+void
+FRTConnection::setError(int errorCode)
+{
+    switch(errorCode) {
+    case FRTE_RPC_CONNECTION:
+    case FRTE_RPC_TIMEOUT:
+        calculateSuspension(TRANSIENT); break;
+    case ErrorCode::UNKNOWN_CONFIG:
+    case ErrorCode::UNKNOWN_DEFINITION:
+    case ErrorCode::UNKNOWN_VERSION:
+    case ErrorCode::UNKNOWN_CONFIGID:
+    case ErrorCode::UNKNOWN_DEF_MD5:
+    case ErrorCode::ILLEGAL_NAME:
+    case ErrorCode::ILLEGAL_VERSION:
+    case ErrorCode::ILLEGAL_CONFIGID:
+    case ErrorCode::ILLEGAL_DEF_MD5:
+    case ErrorCode::ILLEGAL_CONFIG_MD5:
+    case ErrorCode::ILLEGAL_TIMEOUT:
+    case ErrorCode::OUTDATED_CONFIG:
+    case ErrorCode::INTERNAL_ERROR:
+        calculateSuspension(FATAL); break;
+    }
+}
+
+void FRTConnection::setSuccess()
+{
+    _transientFailures = 0;
+    _fatalFailures = 0;
+    _suspendedUntil = 0;
+}
+
+void FRTConnection::calculateSuspension(ErrorType type)
+{
+    int64_t delay = 0;
+    switch(type) {
+    case TRANSIENT:
+        Atomic::postInc(&_transientFailures);
+        delay = _transientFailures * getTransientDelay();
+        if (delay > getMaxTransientDelay()) {
+            delay = getMaxTransientDelay();
+        }
+        LOG(warning, "Connection to %s failed or timed out", _address.c_str());
+        break;
+    case FATAL:
+        Atomic::postInc(&_fatalFailures);
+        delay = _fatalFailures * getFatalDelay();
+        if (delay > getMaxFatalDelay()) {
+            delay = getMaxFatalDelay();
+        }
+        break;
+    }
+    int64_t now = time(0);
+    now *= 1000;
+    _suspendedUntil = now + delay;
+    if (_suspendWarned < (now - 5000)) {
+        char date[32];
+        struct tm* timeinfo;
+        time_t suspendedSeconds = _suspendedUntil / 1000;
+        timeinfo = gmtime(&suspendedSeconds);
+        strftime(date, 32, "%Y-%m-%d %H:%M:%S %Z", timeinfo);
+        LOG(warning, "FRT Connection %s suspended until %s", _address.c_str(), date);
+        _suspendWarned = now;
+    }
+}
+
+}
diff --git a/config/src/vespa/config/frt/frtconnection.h b/config/src/vespa/config/frt/frtconnection.h
new file mode 100644
index 00000000000..a8c0b03b288
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconnection.h
@@ -0,0 +1,58 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <string>
+#include <vespa/fnet/frt/frt.h>
+#include <vespa/vespalib/util/sync.h>
+#include <vespa/vespalib/stllike/string.h>
+#include <vespa/config/common/timingvalues.h>
+#include "connection.h"
+
+namespace config {
+
+class FRTConnection : public Connection {
+
+private:
+    FRTConnection(const FRTConnection&);
+    FRTConnection& operator=(const FRTConnection&);
+
+    const vespalib::string _address;
+    FRT_Supervisor& _supervisor;
+    FRT_Target* _target;
+    int64_t _suspendedUntil;
+    int64_t _suspendWarned;
+    int _transientFailures;
+    int _fatalFailures;
+    int64_t _transientDelay;
+    int64_t _fatalDelay;
+
+    FRT_Target * getTarget();
+
+public:
+    typedef std::shared_ptr<FRTConnection> SP;
+    enum ErrorType { TRANSIENT, FATAL };
+
+    FRTConnection(const vespalib::string & address, FRT_Supervisor & supervisor, const TimingValues & timingValues);
+    ~FRTConnection();
+
+    FRT_RPCRequest * allocRPCRequest()
+    {
+        return _supervisor.AllocRPCRequest();
+    }
+
+    void invoke(FRT_RPCRequest * req, double timeout, FRT_IRequestWait * waiter);
+    const vespalib::string & getAddress() const { return _address; }
+    int64_t getSuspendedUntil() { return _suspendedUntil; }
+    void setError(int errorCode);
+    void setSuccess();
+    void calculateSuspension(ErrorType type);
+    int64_t getTransientDelay() { return _transientDelay; }
+    int64_t getMaxTransientDelay() { return getTransientDelay() * 6; }
+    void setTransientDelay(int64_t delay) { _transientDelay = delay; }
+    int64_t getFatalDelay() { return _fatalDelay; }
+    int64_t getMaxFatalDelay() { return getFatalDelay() * 6; }
+    void setFatalDelay(int64_t delay) { _fatalDelay = delay; }
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/frt/frtconnectionpool.cpp b/config/src/vespa/config/frt/frtconnectionpool.cpp
new file mode 100644
index 00000000000..09630a6b999
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconnectionpool.cpp
@@ -0,0 +1,152 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/fastos/fastos.h>
+#include <cstdlib>
+#include <vespa/vespalib/util/host_name.h>
+#include "frtconnectionpool.h"
+
+namespace config {
+
+FRTConnectionPool::FRTConnectionKey::FRTConnectionKey(int idx, const vespalib::string& hostname)
+    : _idx(idx),
+      _hostname(hostname)
+{
+
+}
+
+int
+FRTConnectionPool::FRTConnectionKey::operator<(const FRTConnectionPool::FRTConnectionKey& right) const
+{
+    return _idx < right._idx;
+}
+
+int
+FRTConnectionPool::FRTConnectionKey::operator==(const FRTConnectionKey& right) const
+{
+    return _hostname == right._hostname;
+}
+
+FRTConnectionPool::FRTConnectionPool(const ServerSpec & spec, const TimingValues & timingValues)
+    : _supervisor(),
+      _selectIdx(0),
+      _hostname("")
+{
+    for (size_t i(0); i < spec.numHosts(); i++) {
+        FRTConnectionKey key(i, spec.getHost(i));
+        _connections[key].reset(new FRTConnection(spec.getHost(i), _supervisor, timingValues));
+    }
+    setHostname();
+    _supervisor.Start();
+}
+
+FRTConnectionPool::~FRTConnectionPool()
+{
+    _supervisor.ShutDown(true);
+}
+
+void
+FRTConnectionPool::syncTransport()
+{
+    _supervisor.GetTransport()->sync();
+}
+
+Connection *
+FRTConnectionPool::getCurrent()
+{
+    if (_hostname.compare("") == 0) {
+        return getNextRoundRobin();
+    } else {
+        return getNextHashBased();
+    }
+}
+
+FRTConnection *
+FRTConnectionPool::getNextRoundRobin()
+{
+    std::vector<FRTConnection *> readySources;
+    getReadySources(readySources);
+    std::vector<FRTConnection *> suspendedSources;
+    getSuspendedSources(suspendedSources);
+    FRTConnection* nextFRTConnection = NULL;
+
+    if (!readySources.empty()) {
+        int sel = _selectIdx % (int)readySources.size();
+        _selectIdx = sel + 1;
+        nextFRTConnection = readySources[sel];
+    } else if (!suspendedSources.empty()) {
+        int sel = _selectIdx % (int)suspendedSources.size();
+        _selectIdx = sel + 1;
+        nextFRTConnection = suspendedSources[sel];
+    }
+    return nextFRTConnection;
+}
+
+FRTConnection *
+FRTConnectionPool::getNextHashBased()
+{
+    std::vector<FRTConnection*> readySources;
+    getReadySources(readySources);
+    std::vector<FRTConnection*> suspendedSources;
+    getSuspendedSources(suspendedSources);
+    FRTConnection* nextFRTConnection = NULL;
+
+    if (!readySources.empty()) {
+        int sel = abs(hashCode(_hostname) % (int)readySources.size());
+        nextFRTConnection = readySources[sel];
+    } else {
+        int sel = abs(hashCode(_hostname) % (int)suspendedSources.size());
+        nextFRTConnection = suspendedSources[sel];
+    }
+    return nextFRTConnection;
+}
+
+const std::vector<FRTConnection *> &
+FRTConnectionPool::getReadySources(std::vector<FRTConnection*> & readySources) const
+{
+    readySources.clear();
+    for (ConnectionMap::const_iterator iter = _connections.begin(); iter != _connections.end(); iter++) {
+        FRTConnection* source = iter->second.get();
+        int64_t tnow = time(0);
+        tnow *= 1000;
+        int64_t timestamp = tnow;
+        if (source->getSuspendedUntil() < timestamp) {
+            readySources.push_back(source);
+        }
+    }
+    return readySources;
+}
+
+const std::vector<FRTConnection *> &
+FRTConnectionPool::getSuspendedSources(std::vector<FRTConnection*> & suspendedSources) const
+{
+    suspendedSources.clear();
+    for (ConnectionMap::const_iterator iter = _connections.begin(); iter != _connections.end(); iter++) {
+        FRTConnection* source = iter->second.get();
+        int64_t tnow = time(0);
+        tnow *= 1000;
+        int64_t timestamp = tnow;
+        if (source->getSuspendedUntil() >= timestamp) {
+            suspendedSources.push_back(source);
+        }
+    }
+    return suspendedSources;
+}
+
+int FRTConnectionPool::hashCode(const vespalib::string & s)
+{
+    int hashval = 0;
+
+    for (int i = 0; i < (int)s.length(); i++) {
+        hashval = 31 * hashval + s[i];
+    }
+    return hashval;
+}
+
+void
+FRTConnectionPool::setHostname()
+{
+    _hostname = vespalib::HostName::get();
+}
+
+
+}
diff --git a/config/src/vespa/config/frt/frtconnectionpool.h b/config/src/vespa/config/frt/frtconnectionpool.h
new file mode 100644
index 00000000000..28f2ee83557
--- /dev/null
+++ b/config/src/vespa/config/frt/frtconnectionpool.h
@@ -0,0 +1,131 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vector>
+#include <string>
+#include <map>
+#include <vespa/fnet/frt/frt.h>
+#include "frtconnection.h"
+#include <vespa/config/subscription/sourcespec.h>
+#include "connectionfactory.h"
+
+namespace config {
+
+class FRTConnectionPool : public ConnectionFactory {
+
+private:
+    FRTConnectionPool(const FRTConnectionPool&);
+    FRTConnectionPool& operator=(const FRTConnectionPool&);
+
+    /**
+     * This class makes it possible to iterate over the entries in the
+     * connections map in the order they were inserted. Used to keep
+     * consistency with the Java version that uses LinkedHashMap.
+     */
+    class FRTConnectionKey {
+    private:
+        int _idx;
+        vespalib::string _hostname;
+    public:
+        FRTConnectionKey() : FRTConnectionKey(0, "") {}
+        FRTConnectionKey(int idx, const vespalib::string& hostname);
+        int operator<(const FRTConnectionKey& right) const;
+        int operator==(const FRTConnectionKey& right) const;
+    };
+
+    FRT_Supervisor _supervisor;
+    int _selectIdx;
+    vespalib::string _hostname;
+    typedef std::map<FRTConnectionKey, FRTConnection::SP> ConnectionMap;
+    ConnectionMap _connections;
+
+public:
+    FRTConnectionPool(const ServerSpec & spec, const TimingValues & timingValues);
+    ~FRTConnectionPool();
+
+    void syncTransport();
+
+    /**
+     * Sets the hostname to the host where this program is running.
+     */
+    void setHostname();
+
+    /**
+     * Sets the hostname.
+     *
+     * @param hostname the hostname
+     */
+    void setHostname(const vespalib::string & hostname) { _hostname = hostname; }
+
+    FNET_Scheduler * getScheduler() { return _supervisor.GetScheduler(); }
+
+    /**
+     * Gets the hostname.
+     *
+     * @return the hostname
+     */
+    vespalib::string & getHostname() { return _hostname; }
+
+    /**
+     * Trim away leading and trailing spaces.
+     *
+     * @param s the string to trim away spaces from
+     * @return string without leading or trailing spaces
+     */
+    vespalib::string trim(vespalib::string s);
+
+    /**
+     * Returns the current FRTConnection instance, taken from the list of error-free sources.
+     * If no sources are error-free, an instance from the list of sources with errors
+     * is returned.
+     *
+     * @return The next FRTConnection instance in the list.
+     */
+    Connection* getCurrent();
+
+    /**
+     * Returns the next FRTConnection instance from the list of error-free sources in a round robin
+     * fashion. If no sources are error-free, an instance from the list of sources with errors
+     * is returned.
+     *
+     * @return The next FRTConnection instance in the list.
+     */
+    FRTConnection* getNextRoundRobin();
+
+    /**
+     * Returns the current FRTConnection instance from the list of error-free sources, based on the
+     * hostname where this program is currently running. If no sources are error-free, an instance
+     * from the list of sources with errors is returned.
+     *
+     * @return The next FRTConnection instance in the list.
+     */
+    FRTConnection* getNextHashBased();
+
+    /**
+     * Gets list of sources that are not suspended.
+     *
+     * @return list of FRTConnection pointers
+     */
+    const std::vector<FRTConnection*> & getReadySources(std::vector<FRTConnection*> & readySources) const;
+
+    /**
+     * Gets list of sources that are suspended.
+     *
+     * @param suspendedSources is list of FRTConnection pointers
+     */
+    const std::vector<FRTConnection*> & getSuspendedSources(std::vector<FRTConnection*> & suspendedSources) const;
+
+    /**
+     * Implementation of the Java hashCode function for the String class.
+     *
+     * Ensures that the same hostname maps to the same configserver/proxy
+     * for both language implementations.
+     *
+     * @param s the string to compute the hash from
+     * @return the hash value
+     */
+    static int hashCode(const vespalib::string & s);
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/frt/frtsource.cpp b/config/src/vespa/config/frt/frtsource.cpp
new file mode 100644
index 00000000000..c209dc69618
--- /dev/null
+++ b/config/src/vespa/config/frt/frtsource.cpp
@@ -0,0 +1,134 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.frt.frtsource");
+#include <vespa/fnet/frt/frt.h>
+#include "frtconfigrequest.h"
+#include "frtconfigresponse.h"
+#include "frtsource.h"
+#include "connection.h"
+#include <vespa/vespalib/util/closuretask.h>
+
+using vespalib::Closure;
+using vespalib::makeClosure;
+
+namespace config {
+
+class GetConfigTask : public FNET_Task {
+public:
+    GetConfigTask(FNET_Scheduler * scheduler, FRTSource * source)
+        : FNET_Task(scheduler),
+          _source(source)
+    {
+    }
+    ~GetConfigTask()
+    {
+        Kill();
+    }
+    void PerformTask()
+    {
+        _source->getConfig();
+    }
+private:
+    FRTSource * _source;
+};
+
+FRTSource::FRTSource(const ConnectionFactory::SP & connectionFactory, const FRTConfigRequestFactory & requestFactory, ConfigAgent::UP agent, const ConfigKey & key)
+    : _connectionFactory(connectionFactory),
+      _requestFactory(requestFactory),
+      _agent(std::move(agent)),
+      _currentRequest(),
+      _key(key),
+      _task(new GetConfigTask(_connectionFactory->getScheduler(), this)),
+      _lock(),
+      _closed(false)
+{
+    LOG(spam, "New source!");
+}
+
+FRTSource::~FRTSource()
+{
+    LOG(spam, "Destructing source");
+    close();
+}
+
+void
+FRTSource::getConfig()
+{
+    int64_t serverTimeout = _agent->getTimeout();
+    double clientTimeout = (serverTimeout / 1000.0) + 5.0; // The additional 5 seconds is the time allowed for the server to respond after serverTimeout has elapsed.
+    Connection * connection = _connectionFactory->getCurrent();
+    const ConfigState & state(_agent->getConfigState());
+ //   LOG(debug, "invoking request with md5 %s, gen %" PRId64 ", servertimeout(%" PRId64 "), client(%f)", state.md5.c_str(), state.generation, serverTimeout, clientTimeout);
+
+
+    FRTConfigRequest::UP request = _requestFactory.createConfigRequest(_key, connection, state, serverTimeout);
+    FRT_RPCRequest * req = request->getRequest();
+
+    _currentRequest = std::move(request);
+    connection->invoke(req, clientTimeout, this);
+}
+
+
+void
+FRTSource::RequestDone(FRT_RPCRequest * request)
+{
+    if (request->GetErrorCode() == FRTE_RPC_ABORT) {
+        LOG(debug, "request aborted, stopping");
+        return;
+    }
+    assert(_currentRequest.get() != NULL);
+    // If this was error from FRT side and nothing to do with config, notify
+    // connection about the error.
+    if (request->IsError()) {
+        _currentRequest->setError(request->GetErrorCode());
+    }
+    _agent->handleResponse(*_currentRequest, _currentRequest->createResponse(request));
+    LOG(spam, "Calling schedule");
+    scheduleNextGetConfig();
+}
+
+void
+FRTSource::close()
+{
+    {
+        vespalib::LockGuard guard(_lock);
+        if (_closed)
+            return;
+        LOG(spam, "Killing task");
+        _task->Kill();
+    }
+    LOG(spam, "Aborting");
+    if (_currentRequest.get() != NULL)
+        _currentRequest->abort();
+    LOG(spam, "Syncing");
+    _connectionFactory->syncTransport();
+    _currentRequest.reset(0);
+    LOG(spam, "closed");
+}
+
+void
+FRTSource::scheduleNextGetConfig()
+{
+    vespalib::LockGuard guard(_lock);
+    if (_closed)
+        return;
+    double sec = _agent->getWaitTime() / 1000.0;
+    LOG(debug, "Scheduling task in %f seconds", sec);
+    _task->Schedule(sec);
+    LOG(debug, "Done scheduling task");
+}
+
+void
+FRTSource::reload(int64_t generation)
+{
+    (void) generation;
+}
+
+const FRTConfigRequest &
+FRTSource::getCurrentRequest() const
+{
+    return *_currentRequest;
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/frt/frtsource.h b/config/src/vespa/config/frt/frtsource.h
new file mode 100644
index 00000000000..2e20bbc4a1a
--- /dev/null
+++ b/config/src/vespa/config/frt/frtsource.h
@@ -0,0 +1,48 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/source.h>
+#include "connectionfactory.h"
+#include "frtconfigagent.h"
+#include <vespa/config/common/configkey.h>
+#include <vespa/config/common/configrequest.h>
+#include "frtconfigrequestfactory.h"
+
+#include <vespa/fnet/frt/frt.h>
+#include <vespa/vespalib/util/sync.h>
+
+namespace config {
+
+/**
+ * Class for sending and receiving config requests via FRT.
+ */
+class FRTSource : public Source,
+                  public FRT_IRequestWait
+{
+public:
+    FRTSource(const ConnectionFactory::SP & connectionFactory, const FRTConfigRequestFactory & requestFactory, ConfigAgent::UP agent, const ConfigKey & key);
+    ~FRTSource();
+
+    void RequestDone(FRT_RPCRequest * request);
+    void close();
+    void reload(int64_t generation);
+    void getConfig();
+
+    const FRTConfigRequest & getCurrentRequest() const;
+
+private:
+    void scheduleNextGetConfig();
+
+    ConnectionFactory::SP _connectionFactory;
+    const FRTConfigRequestFactory & _requestFactory;
+    ConfigAgent::UP _agent;
+    FRTConfigRequest::UP _currentRequest;
+    const ConfigKey _key;
+
+    std::unique_ptr<FNET_Task> _task;
+    vespalib::Lock _lock; // Protects _task and _closed
+    bool _closed;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/frt/frtsourcefactory.cpp b/config/src/vespa/config/frt/frtsourcefactory.cpp
new file mode 100644
index 00000000000..d11b5d6799c
--- /dev/null
+++ b/config/src/vespa/config/frt/frtsourcefactory.cpp
@@ -0,0 +1,23 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.frt.frtsourcefactory");
+#include "frtsourcefactory.h"
+#include "frtsource.h"
+
+namespace config {
+
+FRTSourceFactory::FRTSourceFactory(ConnectionFactory::UP connectionFactory, const TimingValues & timingValues, int protocolVersion, int traceLevel, const VespaVersion & vespaVersion, const CompressionType & compressionType)
+    : _connectionFactory(connectionFactory.release()),
+      _requestFactory(protocolVersion, traceLevel, vespaVersion, compressionType),
+      _timingValues(timingValues)
+{
+}
+
+Source::UP
+FRTSourceFactory::createSource(const IConfigHolder::SP & holder, const ConfigKey & key) const
+{
+    return Source::UP(new FRTSource(_connectionFactory, _requestFactory, ConfigAgent::UP(new FRTConfigAgent(holder, _timingValues)), key));
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/frt/frtsourcefactory.h b/config/src/vespa/config/frt/frtsourcefactory.h
new file mode 100644
index 00000000000..a16a628ee1f
--- /dev/null
+++ b/config/src/vespa/config/frt/frtsourcefactory.h
@@ -0,0 +1,31 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/sourcefactory.h>
+#include <vespa/config/common/timingvalues.h>
+#include "connectionfactory.h"
+#include "frtconfigrequestfactory.h"
+
+namespace config {
+
+/**
+ * Class for sending and receiving config requests via FRT.
+ */
+class FRTSourceFactory : public SourceFactory
+{
+public:
+    FRTSourceFactory(ConnectionFactory::UP connectionFactory, const TimingValues & timingValues, int protocolVersion, int traceLevel, const VespaVersion & vespaVersion, const CompressionType & compressionType);
+
+    /**
+     * Create source handling config described by key.
+     */
+    Source::UP createSource(const IConfigHolder::SP & holder, const ConfigKey & key) const;
+
+private:
+    ConnectionFactory::SP _connectionFactory;
+    FRTConfigRequestFactory _requestFactory;
+    const TimingValues _timingValues;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/frt/protocol.cpp b/config/src/vespa/config/frt/protocol.cpp
new file mode 100644
index 00000000000..be02bc59862
--- /dev/null
+++ b/config/src/vespa/config/frt/protocol.cpp
@@ -0,0 +1,153 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/log/log.h>
+LOG_SETUP(".config.frt.protocol");
+#include "protocol.h"
+#include <lz4.h>
+#include <vespa/vespalib/util/stringfmt.h>
+
+using namespace vespalib;
+using namespace vespalib::slime;
+
+namespace config {
+namespace protocol {
+namespace v2 {
+
+const Memory REQUEST_VERSION = "version";
+const Memory REQUEST_DEF_NAME = "defName";
+const Memory REQUEST_DEF_NAMESPACE = "defNamespace";
+const Memory REQUEST_DEF_MD5 = "defMD5";
+const Memory REQUEST_DEF_CONTENT = "defContent";
+const Memory REQUEST_CLIENT_CONFIGID = "configId";
+const Memory REQUEST_CLIENT_HOSTNAME = "clientHostname";
+const Memory REQUEST_CONFIG_MD5 = "configMD5";
+const Memory REQUEST_CURRENT_GENERATION = "currentGeneration";
+const Memory REQUEST_WANTED_GENERATION = "wantedGeneration";
+const Memory REQUEST_TIMEOUT = "timeout";
+const Memory REQUEST_TRACE = "trace";
+const Memory REQUEST_VESPA_VERSION = "vespaVersion";
+
+const Memory RESPONSE_VERSION = "version";
+const Memory RESPONSE_DEF_NAME = "defName";
+const Memory RESPONSE_DEF_NAMESPACE = "defNamespace";
+const Memory RESPONSE_DEF_MD5 = "defMD5";
+const Memory RESPONSE_CONFIGID = "configId";
+const Memory RESPONSE_CLIENT_HOSTNAME = "clientHostname";
+const Memory RESPONSE_CONFIG_MD5 = "configMD5";
+const Memory RESPONSE_CONFIG_GENERATION = "generation";
+const Memory RESPONSE_PAYLOAD = "payload";
+const Memory RESPONSE_TRACE = "trace";
+
+const Inspector &
+extractPayload(const Slime & data)
+{
+    const Inspector & payload(data.get()[RESPONSE_PAYLOAD]);
+    if (LOG_WOULD_LOG(debug)) {
+        LOG(debug, "payload: %s", payload.toString().c_str());
+    }
+    return payload;
+}
+
+}
+
+namespace v3 {
+const Memory REQUEST_COMPRESSION_TYPE = "compressionType";
+const Memory RESPONSE_COMPRESSION_INFO = "compressionInfo";
+const Memory RESPONSE_COMPRESSION_INFO_TYPE = "compressionType";
+const Memory RESPONSE_COMPRESSION_INFO_UNCOMPRESSED_SIZE = "uncompressedSize";
+
+DecompressedData
+decompress_lz4(const char * input, uint32_t inputLen, int uncompressedLength)
+{
+    DefaultAlloc::UP memory(new DefaultAlloc(uncompressedLength));
+    int sz = LZ4_decompress_safe(input, static_cast<char *>(memory->get()), inputLen, uncompressedLength);
+    if (sz >= 0 && sz != uncompressedLength) {
+        if (LOG_WOULD_LOG(debug)) {
+            LOG(debug, "Returned compressed size (%d) is not the same as uncompressed size(%d)", sz, uncompressedLength);
+        }
+        DefaultAlloc * copy = new DefaultAlloc(sz);
+        memcpy(copy->get(), memory->get(), sz);
+        memory.reset(copy);
+    }
+    assert(sz >= 0);
+    return DecompressedData(std::move(memory), static_cast<uint32_t>(sz));
+}
+
+DecompressedData
+decompress(const char * input, uint32_t len, const CompressionType & compressionType, uint32_t uncompressedLength)
+{
+    // No payload means no data
+    if (len == 0) {
+        return DecompressedData(Memory(input, len), len);
+    }
+    switch (compressionType) {
+        case CompressionType::LZ4:
+            return decompress_lz4(input, len, uncompressedLength);
+            break;
+        case CompressionType::UNCOMPRESSED:
+        default:
+            return DecompressedData(Memory(input, len), len);
+            break;
+    }
+}
+
+}
+
+const int DEFAULT_PROTOCOL_VERSION = 3;
+const int DEFAULT_TRACE_LEVEL = 0;
+
+int
+verifyProtocolVersion(int protocolVersion)
+{
+    if (1 == protocolVersion || 2 == protocolVersion || 3 == protocolVersion) {
+        return protocolVersion;
+    }
+    LOG(info, "Unknown protocol version %d, using default (%d)", protocolVersion, DEFAULT_PROTOCOL_VERSION);
+    return DEFAULT_PROTOCOL_VERSION;
+}
+
+int
+readProtocolVersion()
+{
+    int protocolVersion = DEFAULT_PROTOCOL_VERSION;
+    char *versionStringPtr = getenv("VESPA_CONFIG_PROTOCOL_VERSION");
+    if (versionStringPtr == NULL) {
+        versionStringPtr = getenv("services__config_protocol_version_override");
+    }
+    if (versionStringPtr != NULL) {
+        std::stringstream versionString(versionStringPtr);
+        versionString >> protocolVersion;
+    }
+    return verifyProtocolVersion(protocolVersion);
+}
+
+int
+readTraceLevel()
+{
+    int traceLevel = DEFAULT_TRACE_LEVEL;
+    char *traceLevelStringPtr = getenv("VESPA_CONFIG_PROTOCOL_TRACELEVEL");
+    if (traceLevelStringPtr == NULL) {
+        traceLevelStringPtr = getenv("services__config_protocol_tracelevel");
+    }
+    if (traceLevelStringPtr != NULL) {
+        std::stringstream traceLevelString(traceLevelStringPtr);
+        traceLevelString >> traceLevel;
+    }
+    return traceLevel;
+}
+
+CompressionType
+readProtocolCompressionType()
+{
+    CompressionType type = CompressionType::LZ4;
+    char *compressionTypeStringPtr = getenv("VESPA_CONFIG_PROTOCOL_COMPRESSION");
+    if (compressionTypeStringPtr == NULL) {
+        compressionTypeStringPtr = getenv("services__config_protocol_compression");
+    }
+    if (compressionTypeStringPtr != NULL) {
+        type = stringToCompressionType(vespalib::string(compressionTypeStringPtr));
+    }
+    return type;
+}
+
+}
+}
diff --git a/config/src/vespa/config/frt/protocol.h b/config/src/vespa/config/frt/protocol.h
new file mode 100644
index 00000000000..79d916bf3e7
--- /dev/null
+++ b/config/src/vespa/config/frt/protocol.h
@@ -0,0 +1,85 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/data/slime/slime.h>
+#include <vespa/vespalib/stllike/string.h>
+#include <vespa/config/common/compressiontype.h>
+#include <vespa/vespalib/util/alloc.h>
+
+namespace config {
+
+namespace protocol {
+
+int readProtocolVersion();
+int readTraceLevel();
+CompressionType readProtocolCompressionType();
+
+struct Payload {
+    virtual ~Payload() {}
+    virtual const vespalib::slime::Inspector & getSlimePayload() const = 0;
+};
+
+
+namespace v2 {
+
+extern const vespalib::slime::Memory REQUEST_VERSION;
+extern const vespalib::slime::Memory REQUEST_DEF_NAME;
+extern const vespalib::slime::Memory REQUEST_DEF_NAMESPACE;
+extern const vespalib::slime::Memory REQUEST_DEF_MD5;
+extern const vespalib::slime::Memory REQUEST_DEF_CONTENT;
+extern const vespalib::slime::Memory REQUEST_CLIENT_CONFIGID;
+extern const vespalib::slime::Memory REQUEST_CLIENT_HOSTNAME;
+extern const vespalib::slime::Memory REQUEST_CONFIG_MD5;
+extern const vespalib::slime::Memory REQUEST_CURRENT_GENERATION;
+extern const vespalib::slime::Memory REQUEST_WANTED_GENERATION;
+extern const vespalib::slime::Memory REQUEST_TIMEOUT;
+extern const vespalib::slime::Memory REQUEST_TRACE;
+extern const vespalib::slime::Memory REQUEST_VESPA_VERSION;
+
+extern const vespalib::slime::Memory RESPONSE_VERSION;
+extern const vespalib::slime::Memory RESPONSE_DEF_NAME;
+extern const vespalib::slime::Memory RESPONSE_DEF_NAMESPACE;
+extern const vespalib::slime::Memory RESPONSE_DEF_MD5;
+extern const vespalib::slime::Memory RESPONSE_CONFIGID;
+extern const vespalib::slime::Memory RESPONSE_CLIENT_HOSTNAME;
+extern const vespalib::slime::Memory RESPONSE_CONFIG_MD5;
+extern const vespalib::slime::Memory RESPONSE_CONFIG_GENERATION;
+extern const vespalib::slime::Memory RESPONSE_PAYLOAD;
+extern const vespalib::slime::Memory RESPONSE_TRACE;
+
+const vespalib::slime::Inspector & extractPayload(const vespalib::Slime & data);
+
+}
+
+namespace v3 {
+
+extern const vespalib::slime::Memory REQUEST_COMPRESSION_TYPE;
+extern const vespalib::slime::Memory RESPONSE_COMPRESSION_INFO;
+extern const vespalib::slime::Memory RESPONSE_COMPRESSION_INFO_TYPE;
+extern const vespalib::slime::Memory RESPONSE_COMPRESSION_INFO_UNCOMPRESSED_SIZE;
+
+struct DecompressedData {
+    DecompressedData(vespalib::DefaultAlloc::UP mem, uint32_t sz)
+        : memory(std::move(mem)),
+          memRef(static_cast<const char *>(memory->get()), sz),
+          size(sz)
+    { }
+    DecompressedData(const vespalib::slime::Memory & mem, uint32_t sz)
+        : memory(),
+          memRef(mem),
+          size(sz)
+    {}
+
+    vespalib::DefaultAlloc::UP memory;
+    vespalib::slime::Memory memRef;
+    uint32_t size;
+};
+
+DecompressedData decompress(const char * buf, uint32_t len, const CompressionType & compressionType, uint32_t uncompressedLength);
+
+}
+
+}
+
+}
+
diff --git a/config/src/vespa/config/frt/slimeconfigrequest.cpp b/config/src/vespa/config/frt/slimeconfigrequest.cpp
new file mode 100644
index 00000000000..0f6458d0d66
--- /dev/null
+++ b/config/src/vespa/config/frt/slimeconfigrequest.cpp
@@ -0,0 +1,99 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.frt.slimeconfigrequest");
+#include "slimeconfigrequest.h"
+#include "connection.h"
+#include <vespa/fnet/frt/frt.h>
+#include <vespa/config/common/configkey.h>
+#include <vespa/config/common/configstate.h>
+#include <vespa/config/common/configdefinition.h>
+#include <vespa/config/common/trace.h>
+#include <vespa/config/common/vespa_version.h>
+
+using namespace vespalib;
+using namespace vespalib::slime;
+using namespace vespalib::slime::convenience;
+using namespace config::protocol;
+using namespace config::protocol::v2;
+using namespace config::protocol::v3;
+
+namespace config {
+
+const vespalib::string SlimeConfigRequest::REQUEST_TYPES = "s";
+
+SlimeConfigRequest::SlimeConfigRequest(Connection * connection,
+                                       const ConfigKey & key,
+                                       const vespalib::string & configMd5,
+                                       int64_t currentGeneration,
+                                       int64_t wantedGeneration,
+                                       const vespalib::string & hostName,
+                                       int64_t serverTimeout,
+                                       const Trace & trace,
+                                       const VespaVersion & vespaVersion,
+                                       int64_t protocolVersion,
+                                       const CompressionType & compressionType,
+                                       const vespalib::string & methodName)
+    : FRTConfigRequest(connection, key),
+      _data()
+{
+    populateSlimeRequest(key, configMd5, currentGeneration, wantedGeneration, hostName, serverTimeout, trace, vespaVersion, protocolVersion, compressionType);
+    _request->SetMethodName(methodName.c_str());
+    _parameters.AddString(createJsonFromSlime(_data).c_str());
+}
+
+bool
+SlimeConfigRequest::verifyKey(const ConfigKey & key) const
+{
+    return (key.getDefName().compare(_parameters[0]._string._str) == 0 &&
+            key.getDefNamespace().compare(_parameters[7]._string._str) == 0 &&
+            key.getConfigId().compare(_parameters[3]._string._str) == 0 &&
+            key.getDefMd5().compare(_parameters[2]._string._str) == 0);
+}
+
+bool
+SlimeConfigRequest::verifyState(const ConfigState & state) const
+{
+    return (state.md5.compare(_parameters[4]._string._str) == 0 &&
+            state.generation == static_cast<int64_t>(_parameters[5]._intval64));
+}
+
+void
+SlimeConfigRequest::populateSlimeRequest(const ConfigKey & key,
+                                         const vespalib::string & configMd5,
+                                         int64_t currentGeneration,
+                                         int64_t wantedGeneration,
+                                         const vespalib::string & hostName,
+                                         int64_t serverTimeout,
+                                         const Trace & trace,
+                                         const VespaVersion & vespaVersion,
+                                         int64_t protocolVersion,
+                                         const CompressionType & compressionType)
+{
+    Cursor & root(_data.setObject());
+    root.setLong(REQUEST_VERSION, protocolVersion);
+    root.setString(REQUEST_DEF_NAME, Memory(key.getDefName()));
+    root.setString(REQUEST_DEF_NAMESPACE, Memory(key.getDefNamespace()));
+    root.setString(REQUEST_DEF_MD5, Memory(key.getDefMd5()));
+    ConfigDefinition def(key.getDefSchema());
+    def.serialize(root.setArray(REQUEST_DEF_CONTENT));
+    root.setString(REQUEST_CLIENT_CONFIGID, Memory(key.getConfigId()));
+    root.setString(REQUEST_CLIENT_HOSTNAME, Memory(hostName));
+    root.setString(REQUEST_CONFIG_MD5, Memory(configMd5));
+    root.setLong(REQUEST_CURRENT_GENERATION, currentGeneration);
+    root.setLong(REQUEST_WANTED_GENERATION, wantedGeneration);
+    root.setLong(REQUEST_TIMEOUT, serverTimeout);
+    trace.serialize(root.setObject(REQUEST_TRACE));
+    root.setString(REQUEST_COMPRESSION_TYPE, Memory(compressionTypeToString(compressionType)));
+    root.setString(REQUEST_VESPA_VERSION, Memory(vespaVersion.toString()));
+}
+
+vespalib::string
+SlimeConfigRequest::createJsonFromSlime(const Slime & data)
+{
+    SimpleBuffer buf;
+    JsonFormat::encode(data, buf, true);
+    return buf.get().make_string();
+}
+
+}
diff --git a/config/src/vespa/config/frt/slimeconfigrequest.h b/config/src/vespa/config/frt/slimeconfigrequest.h
new file mode 100644
index 00000000000..af5272597be
--- /dev/null
+++ b/config/src/vespa/config/frt/slimeconfigrequest.h
@@ -0,0 +1,53 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/data/slime/slime.h>
+#include "frtconfigrequest.h"
+#include "protocol.h"
+
+class FRT_Values;
+class FRT_RPCRequest;
+
+namespace config {
+
+class ConfigKey;
+class Connection;
+class Trace;
+class VespaVersion;
+
+class SlimeConfigRequest : public FRTConfigRequest {
+public:
+    SlimeConfigRequest(Connection * connection,
+                       const ConfigKey & key,
+                       const vespalib::string & configMd5,
+                       int64_t currentGeneration,
+                       int64_t wantedGeneration,
+                       const vespalib::string & hostName,
+                       int64_t serverTimeout,
+                       const Trace & trace,
+                       const VespaVersion & vespaVersion,
+                       int64_t protocolVersion,
+                       const CompressionType & compressionType,
+                       const vespalib::string & methodName);
+    virtual ~SlimeConfigRequest() {}
+    bool verifyKey(const ConfigKey & key) const;
+    bool verifyState(const ConfigState & state) const;
+    virtual ConfigResponse::UP createResponse(FRT_RPCRequest * request) const = 0;
+private:
+    void populateSlimeRequest(const ConfigKey & key,
+                              const vespalib::string & configMd5,
+                              int64_t currentGeneration,
+                              int64_t wantedGeneration,
+                              const vespalib::string & hostName,
+                              int64_t serverTimeout,
+                              const Trace & trace,
+                              const VespaVersion & vespaVersion,
+                              int64_t protocolVersion,
+                              const CompressionType & compressionType);
+    static vespalib::string createJsonFromSlime(const vespalib::Slime & data);
+    static const vespalib::string REQUEST_TYPES;
+    vespalib::Slime _data;
+};
+
+}
+
diff --git a/config/src/vespa/config/frt/slimeconfigresponse.cpp b/config/src/vespa/config/frt/slimeconfigresponse.cpp
new file mode 100644
index 00000000000..ac84852b256
--- /dev/null
+++ b/config/src/vespa/config/frt/slimeconfigresponse.cpp
@@ -0,0 +1,78 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.frt.slimeconfigresponse");
+#include "slimeconfigresponse.h"
+#include <vespa/config/common/misc.h>
+#include <vespa/fnet/frt/frt.h>
+#include <vespa/vespalib/stllike/string.h>
+
+using namespace vespalib;
+using namespace vespalib::slime;
+using namespace vespalib::slime::convenience;
+using namespace config::protocol::v2;
+
+namespace config {
+
+SlimeConfigResponse::SlimeConfigResponse(FRT_RPCRequest * request)
+    : FRTConfigResponse(request),
+      _key(),
+      _value(),
+      _trace(),
+      _filled(false)
+{
+}
+
+void
+SlimeConfigResponse::fill()
+{
+    if (_filled) {
+        LOG(info, "SlimeConfigResponse::fill() called twice, probably a bug");
+        return;
+    }
+    Memory json((*_returnValues)[0]._string._str);
+    Slime * data = new Slime();
+    JsonFormat::decode(json, *data);
+    _data.reset(data);
+    _key = readKey();
+    _state = readState();
+    _value = readConfigValue();
+    readTrace();
+    _filled = true;
+    if (LOG_WOULD_LOG(debug)) {
+        LOG(debug, "trace at return(%s)", _trace.toString().c_str());
+    }
+}
+
+void
+SlimeConfigResponse::readTrace()
+{
+    Inspector & root(_data->get());
+    _trace.deserialize(root[RESPONSE_TRACE]);
+}
+
+const ConfigKey
+SlimeConfigResponse::readKey() const
+{
+    Inspector & root(_data->get());
+    return ConfigKey(root[RESPONSE_CONFIGID].asString().make_string(),
+                     root[RESPONSE_DEF_NAME].asString().make_string(),
+                     root[RESPONSE_DEF_NAMESPACE].asString().make_string(),
+                     root[RESPONSE_DEF_MD5].asString().make_string());
+}
+
+const ConfigState
+SlimeConfigResponse::readState() const
+{
+    const Slime & data(*_data);
+    return ConfigState(data.get()[RESPONSE_CONFIG_MD5].asString().make_string(),  data.get()[RESPONSE_CONFIG_GENERATION].asLong());
+}
+
+vespalib::string
+SlimeConfigResponse::getHostName() const
+{
+    Inspector & root(_data->get());
+    return root[RESPONSE_CLIENT_HOSTNAME].asString().make_string();
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/frt/slimeconfigresponse.h b/config/src/vespa/config/frt/slimeconfigresponse.h
new file mode 100644
index 00000000000..4f22f0726bc
--- /dev/null
+++ b/config/src/vespa/config/frt/slimeconfigresponse.h
@@ -0,0 +1,56 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "frtconfigresponse.h"
+#include <vespa/config/common/configkey.h>
+#include <vespa/config/common/configvalue.h>
+#include <vespa/config/common/trace.h>
+#include <vespa/config/common/misc.h>
+#include <vespa/vespalib/data/slime/slime.h>
+#include "protocol.h"
+
+class FRT_RPCRequest;
+class FRT_Values;
+
+namespace config {
+
+/**
+ * Baseclass for config responses.
+ */
+class SlimeConfigResponse : public FRTConfigResponse {
+private:
+    SlimeConfigResponse& operator=(const SlimeConfigResponse&);
+public:
+    SlimeConfigResponse(FRT_RPCRequest * request);
+    virtual ~SlimeConfigResponse() {}
+
+    const ConfigKey & getKey() const { return _key; }
+    const ConfigValue & getValue() const { return _value; }
+    const ConfigState & getConfigState() const { return _state; }
+    const Trace & getTrace() const { return _trace; }
+
+    vespalib::string getHostName() const;
+    vespalib::string getConfigMd5() const;
+
+    void fill();
+
+protected:
+    virtual const ConfigValue readConfigValue() const = 0;
+
+private:
+    ConfigKey _key;
+    ConfigValue _value;
+    ConfigState _state;
+    Trace _trace;
+    bool _filled;
+
+    const ConfigKey readKey() const;
+    const ConfigState readState() const;
+    void readTrace();
+
+protected:
+    SlimePtr _data;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/helper/.gitignore b/config/src/vespa/config/helper/.gitignore
new file mode 100644
index 00000000000..7e7c0fe7fae
--- /dev/null
+++ b/config/src/vespa/config/helper/.gitignore
@@ -0,0 +1,2 @@
+/.depend
+/Makefile
diff --git a/config/src/vespa/config/helper/CMakeLists.txt b/config/src/vespa/config/helper/CMakeLists.txt
new file mode 100644
index 00000000000..bc1688364bc
--- /dev/null
+++ b/config/src/vespa/config/helper/CMakeLists.txt
@@ -0,0 +1,9 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_library(config_helper OBJECT
+    SOURCES
+    configfetcher.cpp
+    legacysubscriber.cpp
+    legacy.cpp
+    configpoller.cpp
+    DEPENDS
+)
diff --git a/config/src/vespa/config/helper/configfetcher.cpp b/config/src/vespa/config/helper/configfetcher.cpp
new file mode 100644
index 00000000000..f6e39523900
--- /dev/null
+++ b/config/src/vespa/config/helper/configfetcher.cpp
@@ -0,0 +1,53 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/log/log.h>
+LOG_SETUP(".config.helper.configfetcher");
+#include "configfetcher.h"
+
+namespace config {
+
+ConfigFetcher::ConfigFetcher(const IConfigContext::SP & context)
+    : _poller(context),
+      _thread(_poller),
+      _closed(false),
+      _started(false)
+{
+}
+
+ConfigFetcher::ConfigFetcher(const SourceSpec & spec)
+    : _poller(IConfigContext::SP(new ConfigContext(spec))),
+      _thread(_poller),
+      _closed(false),
+      _started(false)
+{
+}
+
+void
+ConfigFetcher::start()
+{
+    if (!_closed) {
+        LOG(debug, "Polling for config");
+        _poller.poll();
+        LOG(debug, "Starting fetcher thread...");
+        _thread.start();
+        _started = true;
+        LOG(debug, "Fetcher thread started");
+    }
+}
+
+ConfigFetcher::~ConfigFetcher()
+{
+    close();
+}
+
+void
+ConfigFetcher::close()
+{
+    if (!_closed) {
+        _poller.close();
+        if (_started)
+            _thread.join();
+    }
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/helper/configfetcher.h b/config/src/vespa/config/helper/configfetcher.h
new file mode 100644
index 00000000000..ad7c2a8b549
--- /dev/null
+++ b/config/src/vespa/config/helper/configfetcher.h
@@ -0,0 +1,44 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/config.h>
+#include <vespa/config/common/timingvalues.h>
+#include <vespa/vespalib/util/thread.h>
+#include "configpoller.h"
+
+#include <atomic>
+
+namespace config {
+
+/**
+ * A config fetcher subscribes to a config and notifies a callback when done
+ */
+class ConfigFetcher
+{
+public:
+    ConfigFetcher(const IConfigContext::SP & context);
+    ConfigFetcher(const SourceSpec & spec = ServerSpec());
+    ~ConfigFetcher();
+
+    template <typename ConfigType>
+    void subscribe(const std::string & configId, IFetcherCallback<ConfigType> * callback, uint64_t subscribeTimeout = DEFAULT_SUBSCRIBE_TIMEOUT);
+
+    void subscribeGenerationChanges(IGenerationCallback * callback) {
+        _poller.subscribeGenerationChanges(callback);
+    }
+
+    void start();
+    void close();
+    int64_t getGeneration() const { return _poller.getGeneration(); }
+private:
+    ConfigPoller _poller;
+    vespalib::Thread _thread;
+    std::atomic<bool> _closed;
+    std::atomic<bool> _started;
+};
+
+} // namespace config
+
+
+#include "configfetcher.hpp"
+
diff --git a/config/src/vespa/config/helper/configfetcher.hpp b/config/src/vespa/config/helper/configfetcher.hpp
new file mode 100644
index 00000000000..9567c716029
--- /dev/null
+++ b/config/src/vespa/config/helper/configfetcher.hpp
@@ -0,0 +1,12 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+namespace config {
+
+template <typename ConfigType>
+void
+ConfigFetcher::subscribe(const std::string & configId, IFetcherCallback<ConfigType> * callback, uint64_t subscribeTimeout)
+{
+    _poller.subscribe<ConfigType>(configId, callback, subscribeTimeout);
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/helper/configgetter.h b/config/src/vespa/config/helper/configgetter.h
new file mode 100644
index 00000000000..ee0cba1988c
--- /dev/null
+++ b/config/src/vespa/config/helper/configgetter.h
@@ -0,0 +1,29 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/config.h>
+#include <vespa/config/common/timingvalues.h>
+#include <vespa/config/subscription/confighandle.h>
+#include <vespa/vespalib/util/threadstackexecutor.h>
+#include "ifetchercallback.h"
+
+namespace config {
+
+/**
+ * A config fetcher subscribes to a config and notifies a callback when done
+ */
+template <typename ConfigType>
+class ConfigGetter
+{
+public:
+    static std::unique_ptr<ConfigType> getConfig(int64_t &generation, const std::string & configId, const SourceSpec & spec = ServerSpec());
+    static std::unique_ptr<ConfigType> getConfig(int64_t &generation, const std::string & configId, const IConfigContext::SP & context, uint64_t subscribeTimeout = DEFAULT_SUBSCRIBE_TIMEOUT);
+    static std::unique_ptr<ConfigType> getConfig(const std::string & configId, const SourceSpec & spec = ServerSpec());
+    static std::unique_ptr<ConfigType> getConfig(const std::string & configId, const IConfigContext::SP & context, uint64_t subscribeTimeout = DEFAULT_SUBSCRIBE_TIMEOUT);
+};
+
+} // namespace config
+
+
+#include "configgetter.hpp"
+
diff --git a/config/src/vespa/config/helper/configgetter.hpp b/config/src/vespa/config/helper/configgetter.hpp
new file mode 100644
index 00000000000..5452908a144
--- /dev/null
+++ b/config/src/vespa/config/helper/configgetter.hpp
@@ -0,0 +1,43 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+namespace config {
+
+template <typename ConfigType>
+std::unique_ptr<ConfigType>
+ConfigGetter<ConfigType>::getConfig(int64_t &generation, const std::string & configId, const SourceSpec & spec)
+{
+    ConfigSubscriber s(spec);
+    std::unique_ptr< ConfigHandle<ConfigType> > h = s.subscribe<ConfigType>(configId);
+    s.nextConfig(0);
+    generation = s.getGeneration();
+    return h->getConfig();
+}
+
+template <typename ConfigType>
+std::unique_ptr<ConfigType>
+ConfigGetter<ConfigType>::getConfig(int64_t &generation, const std::string & configId, const IConfigContext::SP & context, uint64_t subscribeTimeout)
+{
+    ConfigSubscriber s(context);
+    std::unique_ptr< ConfigHandle<ConfigType> > h = s.subscribe<ConfigType>(configId, subscribeTimeout);
+    s.nextConfig(0);
+    generation = s.getGeneration();
+    return h->getConfig();
+}
+
+template <typename ConfigType>
+std::unique_ptr<ConfigType>
+ConfigGetter<ConfigType>::getConfig(const std::string & configId, const SourceSpec & spec)
+{
+    int64_t ignoreGeneration;
+    return getConfig(ignoreGeneration, configId, spec);
+}
+
+template <typename ConfigType>
+std::unique_ptr<ConfigType>
+ConfigGetter<ConfigType>::getConfig(const std::string & configId, const IConfigContext::SP & context, uint64_t subscribeTimeout)
+{
+    int64_t ignoreGeneration;
+    return getConfig(ignoreGeneration, configId, context, subscribeTimeout);
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/helper/configpoller.cpp b/config/src/vespa/config/helper/configpoller.cpp
new file mode 100644
index 00000000000..281fe8df140
--- /dev/null
+++ b/config/src/vespa/config/helper/configpoller.cpp
@@ -0,0 +1,57 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/log/log.h>
+LOG_SETUP(".config.helper.configpoller");
+#include "configpoller.h"
+
+namespace config {
+
+ConfigPoller::ConfigPoller(const IConfigContext::SP & context)
+    : _generation(-1),
+      _subscriber(context),
+      _handleList(),
+      _callbackList(),
+      _genCallback(0)
+{
+}
+
+void
+ConfigPoller::run()
+{
+    while (!_subscriber.isClosed()) {
+        try {
+            poll();
+        } catch (const std::exception & e) {
+            LOG(fatal, "Fatal error while configuring: %s", e.what());
+        }
+    }
+}
+
+void
+ConfigPoller::poll()
+{
+    LOG(debug, "Checking for new config");
+    if (_subscriber.nextGeneration()) {
+        if (_subscriber.isClosed())
+            return;
+        LOG(debug, "Got new config, reconfiguring");
+        _generation = _subscriber.getGeneration();
+        for (size_t i = 0; i < _handleList.size(); i++) {
+            ICallback * callback(_callbackList[i]);
+            if (_handleList[i]->isChanged())
+                callback->configure(std::move(_handleList[i]->getConfig()));
+        }
+        if (_genCallback) {
+            _genCallback->notifyGenerationChange(_generation);
+        }
+    } else {
+        LOG(debug, "No new config available");
+    }
+}
+
+void
+ConfigPoller::close()
+{
+    _subscriber.close();
+}
+
+}
diff --git a/config/src/vespa/config/helper/configpoller.h b/config/src/vespa/config/helper/configpoller.h
new file mode 100644
index 00000000000..f614cab5175
--- /dev/null
+++ b/config/src/vespa/config/helper/configpoller.h
@@ -0,0 +1,39 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/subscription/configsubscriber.h>
+#include <vespa/config/common/timingvalues.h>
+#include <vespa/vespalib/util/runnable.h>
+#include "ifetchercallback.h"
+#include "ihandle.h"
+
+namespace config {
+
+/**
+ * A config poller runs a polling sequence on a set of configs that it has
+ * subscribed to.
+ */
+class ConfigPoller : public vespalib::Runnable {
+public:
+    ConfigPoller(const IConfigContext::SP & context);
+    void run();
+    template <typename ConfigType>
+    void subscribe(const std::string & configId, IFetcherCallback<ConfigType> * callback, uint64_t subscribeTimeout = DEFAULT_SUBSCRIBE_TIMEOUT);
+    void subscribeGenerationChanges(IGenerationCallback * callback) { _genCallback = callback; }
+    void poll();
+    void close();
+    int64_t getGeneration() const { return _generation; }
+private:
+    int64_t _generation;
+    ConfigSubscriber _subscriber;
+    std::vector<IHandle::UP> _handleList;
+    std::vector<ICallback *> _callbackList;
+    IGenerationCallback *_genCallback;
+};
+
+
+} // namespace config
+
+#include "configpoller.hpp"
+
+
diff --git a/config/src/vespa/config/helper/configpoller.hpp b/config/src/vespa/config/helper/configpoller.hpp
new file mode 100644
index 00000000000..96e6ea334e8
--- /dev/null
+++ b/config/src/vespa/config/helper/configpoller.hpp
@@ -0,0 +1,15 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+namespace config {
+
+template <typename ConfigType>
+void
+ConfigPoller::subscribe(const std::string & configId, IFetcherCallback<ConfigType> * callback, uint64_t subscribeTimeout)
+{
+
+    std::unique_ptr<ConfigHandle<ConfigType> > handle(_subscriber.subscribe<ConfigType>(configId, subscribeTimeout));
+    _handleList.emplace_back(std::make_unique<GenericHandle<ConfigType>>(std::move(handle)));
+    _callbackList.push_back(callback);
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/helper/ifetchercallback.h b/config/src/vespa/config/helper/ifetchercallback.h
new file mode 100644
index 00000000000..19ad4a8984b
--- /dev/null
+++ b/config/src/vespa/config/helper/ifetchercallback.h
@@ -0,0 +1,39 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/configgen/configinstance.h>
+
+namespace config {
+
+class IGenerationCallback
+{
+public:
+    virtual void notifyGenerationChange(int64_t generation) = 0;
+    virtual ~IGenerationCallback() {}
+};
+
+class ICallback
+{
+public:
+    virtual void configure(std::unique_ptr<const ConfigInstance> config) = 0;
+    virtual ~ICallback() { }
+};
+
+/**
+ * Interface for callback methods used by ConfigFetcher, ConfigPoller and
+ * LegacySubscriber.
+ */
+template <typename ConfigType>
+class IFetcherCallback : public ICallback
+{
+public:
+    virtual ~IFetcherCallback() { }
+protected:
+    virtual void configure(std::unique_ptr<const ConfigInstance> config) {
+        configure(std::unique_ptr<ConfigType>(static_cast<const ConfigType *>(config.release())));
+    }
+    virtual void configure(std::unique_ptr<ConfigType> config) = 0;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/helper/ihandle.h b/config/src/vespa/config/helper/ihandle.h
new file mode 100644
index 00000000000..d84f324487a
--- /dev/null
+++ b/config/src/vespa/config/helper/ihandle.h
@@ -0,0 +1,35 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/subscription/confighandle.h>
+
+namespace config {
+
+class IHandle
+{
+public:
+    typedef std::unique_ptr<IHandle> UP;
+    virtual std::unique_ptr<const ConfigInstance> getConfig() = 0;
+    virtual bool isChanged() = 0;
+    virtual ~IHandle() { }
+};
+
+template <typename ConfigType>
+class GenericHandle : public IHandle
+{
+public:
+    GenericHandle(std::unique_ptr<ConfigHandle<ConfigType> > handle)
+        : _handle(std::move(handle))
+    {
+    }
+
+    std::unique_ptr<const ConfigInstance> getConfig() {
+        return std::unique_ptr<const ConfigInstance>(_handle->getConfig().release());
+    }
+    bool isChanged() { return _handle->isChanged(); }
+private:
+    std::unique_ptr<ConfigHandle <ConfigType> > _handle;
+};
+
+}
+
diff --git a/config/src/vespa/config/helper/legacy.cpp b/config/src/vespa/config/helper/legacy.cpp
new file mode 100644
index 00000000000..5598769f07d
--- /dev/null
+++ b/config/src/vespa/config/helper/legacy.cpp
@@ -0,0 +1,67 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "legacy.h"
+#include <vespa/vespalib/io/fileutil.h>
+
+namespace {
+    bool isFileLegacy(const std::string & configId) {
+        return configId.compare(0, 5, "file:") == 0;
+    }
+    bool isDirLegacy(const std::string & configId) {
+        return configId.compare(0, 4, "dir:") == 0;
+    }
+    const std::string dirNameFromId(const std::string & configId) {
+        return configId.substr(4);
+    }
+    const std::string createFileSpecFromId(const std::string & configId) {
+        return configId.substr(5);
+    }
+    const std::string createBaseId(const std::string & configId) {
+        std::string::size_type end = configId.find_last_of(".");
+        return configId.substr(5, end - 5);
+    }
+    bool isRawLegacy(const std::string & configId) {
+        return configId.compare(0, 4, "raw:") == 0;
+    }
+    const std::string createRawSpecFromId(const std::string & configId) {
+        return configId.substr(4);
+    }
+}
+
+namespace config {
+
+bool
+isLegacyConfigId(const std::string & configId)
+{
+    return (isRawLegacy(configId) ||
+            isFileLegacy(configId) ||
+            isDirLegacy(configId));
+}
+
+std::unique_ptr<SourceSpec>
+legacyConfigId2Spec(const std::string & configId)
+{
+    std::unique_ptr<SourceSpec> spec(new ServerSpec());
+    if (isFileLegacy(configId)) {
+        spec.reset(new FileSpec(createFileSpecFromId(configId)));
+    } else if (isDirLegacy(configId)) {
+        spec.reset(new DirSpec(dirNameFromId(configId)));
+    } else if (isRawLegacy(configId)) {
+        spec.reset(new RawSpec(createRawSpecFromId(configId)));
+    }
+    return spec;
+}
+
+const std::string
+legacyConfigId2ConfigId(const std::string & configId)
+{
+    std::string newId(configId);
+    if (isFileLegacy(configId)) {
+        newId = createBaseId(configId);
+    } else if (isRawLegacy(configId) || isDirLegacy(configId)) {
+        newId = "";
+    }
+    return newId;
+}
+
+}
diff --git a/config/src/vespa/config/helper/legacy.h b/config/src/vespa/config/helper/legacy.h
new file mode 100644
index 00000000000..530d613bba8
--- /dev/null
+++ b/config/src/vespa/config/helper/legacy.h
@@ -0,0 +1,15 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <string>
+#include <vespa/config/subscription/sourcespec.h>
+
+namespace config {
+
+bool isLegacyConfigId(const std::string & configId);
+std::unique_ptr<SourceSpec> legacyConfigId2Spec(const std::string & configId);
+const std::string legacyConfigId2ConfigId(const std::string & configId);
+
+}
+
+
diff --git a/config/src/vespa/config/helper/legacysubscriber.cpp b/config/src/vespa/config/helper/legacysubscriber.cpp
new file mode 100644
index 00000000000..1adde34c4a7
--- /dev/null
+++ b/config/src/vespa/config/helper/legacysubscriber.cpp
@@ -0,0 +1,20 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "legacysubscriber.h"
+
+namespace config {
+
+LegacySubscriber::LegacySubscriber()
+    : _fetcher(),
+      _configId()
+{
+}
+
+void
+LegacySubscriber::close()
+{
+    if (_fetcher.get() != NULL)
+        _fetcher->close();
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/helper/legacysubscriber.h b/config/src/vespa/config/helper/legacysubscriber.h
new file mode 100644
index 00000000000..714e465572d
--- /dev/null
+++ b/config/src/vespa/config/helper/legacysubscriber.h
@@ -0,0 +1,31 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "configfetcher.h"
+#include <vespa/config/subscription/sourcespec.h>
+#include "legacy.h"
+
+namespace config {
+
+/**
+ * A LegacySubscriber subscribes for a config similar to the old config API.
+ */
+class LegacySubscriber
+{
+public:
+    LegacySubscriber();
+    const vespalib::string & id() const { return _configId; }
+
+    template <typename ConfigType>
+    void subscribe(const std::string & configId, IFetcherCallback<ConfigType> * callback);
+
+    void close();
+private:
+    std::unique_ptr<ConfigFetcher> _fetcher;
+    vespalib::string _configId;
+};
+
+} // namespace config
+
+#include "legacysubscriber.hpp"
+
diff --git a/config/src/vespa/config/helper/legacysubscriber.hpp b/config/src/vespa/config/helper/legacysubscriber.hpp
new file mode 100644
index 00000000000..fb91e79c915
--- /dev/null
+++ b/config/src/vespa/config/helper/legacysubscriber.hpp
@@ -0,0 +1,22 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+namespace config {
+
+template <typename ConfigType>
+void
+LegacySubscriber::subscribe(const std::string & configId, IFetcherCallback<ConfigType> * callback)
+{
+    if (isLegacyConfigId(configId)) {
+        std::string legacyId(legacyConfigId2ConfigId(configId));
+        std::unique_ptr<SourceSpec> spec(legacyConfigId2Spec(configId));
+        _fetcher.reset(new ConfigFetcher(IConfigContext::SP(new ConfigContext(*spec))));
+        _fetcher->subscribe<ConfigType>(legacyId, callback);
+    } else {
+        _fetcher.reset(new ConfigFetcher());
+        _fetcher->subscribe<ConfigType>(configId, callback);
+    }
+    _configId = configId;
+    _fetcher->start();
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/print.h b/config/src/vespa/config/print.h
new file mode 100644
index 00000000000..0b0471c9e13
--- /dev/null
+++ b/config/src/vespa/config/print.h
@@ -0,0 +1,23 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/print/configwriter.h>
+#include <vespa/config/print/fileconfigwriter.h>
+#include <vespa/config/print/ostreamconfigwriter.h>
+#include <vespa/config/print/asciiconfigwriter.h>
+#include <vespa/config/print/asciiconfigwriter.h>
+#include <vespa/config/print/configformatter.h>
+#include <vespa/config/print/jsonconfigformatter.h>
+#include <vespa/config/print/fileconfigformatter.h>
+#include <vespa/config/print/fileconfigsnapshotwriter.h>
+#include <vespa/config/print/fileconfigsnapshotreader.h>
+#include <vespa/config/print/asciiconfigsnapshotwriter.h>
+#include <vespa/config/print/asciiconfigsnapshotreader.h>
+
+/**
+ * @section DESCRIPTION
+ *
+ * This file contains all necessary includes as well as functions used to print
+ * config.
+ */
+
diff --git a/config/src/vespa/config/print/.gitignore b/config/src/vespa/config/print/.gitignore
new file mode 100644
index 00000000000..7e7c0fe7fae
--- /dev/null
+++ b/config/src/vespa/config/print/.gitignore
@@ -0,0 +1,2 @@
+/.depend
+/Makefile
diff --git a/config/src/vespa/config/print/CMakeLists.txt b/config/src/vespa/config/print/CMakeLists.txt
new file mode 100644
index 00000000000..469ec46f0a8
--- /dev/null
+++ b/config/src/vespa/config/print/CMakeLists.txt
@@ -0,0 +1,14 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_library(config_print OBJECT
+    SOURCES
+    fileconfigformatter.cpp
+    asciiconfigwriter.cpp
+    fileconfigwriter.cpp
+    ostreamconfigwriter.cpp
+    jsonconfigformatter.cpp
+    fileconfigsnapshotwriter.cpp
+    fileconfigsnapshotreader.cpp
+    asciiconfigsnapshotwriter.cpp
+    asciiconfigsnapshotreader.cpp
+    DEPENDS
+)
diff --git a/config/src/vespa/config/print/asciiconfigreader.h b/config/src/vespa/config/print/asciiconfigreader.h
new file mode 100644
index 00000000000..135d2d4d51f
--- /dev/null
+++ b/config/src/vespa/config/print/asciiconfigreader.h
@@ -0,0 +1,27 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/asciistream.h>
+#include "configreader.h"
+#include "configformatter.h"
+
+namespace config {
+
+/**
+ * Read a config from istream
+ */
+template <typename ConfigType>
+class AsciiConfigReader : public ConfigReader<ConfigType>
+{
+public:
+    AsciiConfigReader(vespalib::asciistream & is);
+    std::unique_ptr<ConfigType> read();
+    std::unique_ptr<ConfigType> read(const ConfigFormatter & formatter);
+private:
+    vespalib::asciistream & _is;
+};
+
+} // namespace config
+
+#include "asciiconfigreader.hpp"
+
diff --git a/config/src/vespa/config/print/asciiconfigreader.hpp b/config/src/vespa/config/print/asciiconfigreader.hpp
new file mode 100644
index 00000000000..bc73f1285e2
--- /dev/null
+++ b/config/src/vespa/config/print/asciiconfigreader.hpp
@@ -0,0 +1,33 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+namespace config {
+
+template <typename ConfigType>
+AsciiConfigReader<ConfigType>::AsciiConfigReader(vespalib::asciistream & is)
+    : _is(is)
+{
+}
+
+template <typename ConfigType>
+std::unique_ptr<ConfigType>
+AsciiConfigReader<ConfigType>::read(const ConfigFormatter & formatter)
+{
+    ConfigDataBuffer buffer;
+    buffer.setEncodedString(_is.str());
+    formatter.decode(buffer);
+    return std::unique_ptr<ConfigType>(new ConfigType(buffer));
+}
+
+template <typename ConfigType>
+std::unique_ptr<ConfigType>
+AsciiConfigReader<ConfigType>::read()
+{
+    std::vector<vespalib::string> lines;
+    vespalib::string line;
+    while (getline(_is, line)) {
+        lines.push_back(line);
+    }
+    return std::unique_ptr<ConfigType>(new ConfigType(ConfigValue(lines, calculateContentMd5(lines))));
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/print/asciiconfigsnapshotreader.cpp b/config/src/vespa/config/print/asciiconfigsnapshotreader.cpp
new file mode 100644
index 00000000000..83fc8f55cfd
--- /dev/null
+++ b/config/src/vespa/config/print/asciiconfigsnapshotreader.cpp
@@ -0,0 +1,25 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "asciiconfigsnapshotreader.h"
+#include "jsonconfigformatter.h"
+
+namespace config {
+
+AsciiConfigSnapshotReader::AsciiConfigSnapshotReader(const vespalib::asciistream & is)
+    : _is(is)
+{
+}
+
+ConfigSnapshot
+AsciiConfigSnapshotReader::read()
+{
+    ConfigDataBuffer buffer;
+    buffer.setEncodedString(_is.str());
+    JsonConfigFormatter formatter(true);
+    formatter.decode(buffer);
+    ConfigSnapshot snapshot;
+    snapshot.deserialize(buffer);
+    return snapshot;
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/print/asciiconfigsnapshotreader.h b/config/src/vespa/config/print/asciiconfigsnapshotreader.h
new file mode 100644
index 00000000000..28120b38b93
--- /dev/null
+++ b/config/src/vespa/config/print/asciiconfigsnapshotreader.h
@@ -0,0 +1,27 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/asciistream.h>
+#include "configsnapshotreader.h"
+
+namespace config {
+
+/**
+ * Read config snapshots from an ascii stream.
+ */
+class AsciiConfigSnapshotReader : public ConfigSnapshotReader {
+public:
+    AsciiConfigSnapshotReader(const vespalib::asciistream & is);
+
+    /**
+     * Read a config snapshot.
+     *
+     * @return Snapshot containing the configs.
+     */
+    ConfigSnapshot read();
+private:
+    const vespalib::asciistream & _is;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/print/asciiconfigsnapshotwriter.cpp b/config/src/vespa/config/print/asciiconfigsnapshotwriter.cpp
new file mode 100644
index 00000000000..a338e88b862
--- /dev/null
+++ b/config/src/vespa/config/print/asciiconfigsnapshotwriter.cpp
@@ -0,0 +1,24 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "asciiconfigsnapshotwriter.h"
+#include "jsonconfigformatter.h"
+
+namespace config {
+
+AsciiConfigSnapshotWriter::AsciiConfigSnapshotWriter(vespalib::asciistream & os)
+    : _os(os)
+{
+}
+
+bool
+AsciiConfigSnapshotWriter::write(const ConfigSnapshot & snapshot)
+{
+    ConfigDataBuffer buffer;
+    snapshot.serialize(buffer);
+    JsonConfigFormatter formatter(true);
+    formatter.encode(buffer);
+    _os << buffer.getEncodedString();
+    return !_os.fail();
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/print/asciiconfigsnapshotwriter.h b/config/src/vespa/config/print/asciiconfigsnapshotwriter.h
new file mode 100644
index 00000000000..f49da791477
--- /dev/null
+++ b/config/src/vespa/config/print/asciiconfigsnapshotwriter.h
@@ -0,0 +1,21 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/asciistream.h>
+#include "configsnapshotwriter.h"
+
+namespace config {
+
+/**
+ * Write a config snapshot to an ascii stream.
+ */
+class AsciiConfigSnapshotWriter : public ConfigSnapshotWriter {
+public:
+    AsciiConfigSnapshotWriter(vespalib::asciistream & os);
+    bool write(const ConfigSnapshot & snapshot);
+private:
+    vespalib::asciistream & _os;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/print/asciiconfigwriter.cpp b/config/src/vespa/config/print/asciiconfigwriter.cpp
new file mode 100644
index 00000000000..9f738fe716a
--- /dev/null
+++ b/config/src/vespa/config/print/asciiconfigwriter.cpp
@@ -0,0 +1,29 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "asciiconfigwriter.h"
+#include "fileconfigformatter.h"
+
+namespace config {
+
+AsciiConfigWriter::AsciiConfigWriter(vespalib::asciistream & os)
+    : _os(os)
+{
+}
+
+bool
+AsciiConfigWriter::write(const ConfigInstance & config)
+{
+    return write(config, FileConfigFormatter());
+}
+
+bool
+AsciiConfigWriter::write(const ConfigInstance & config, const ConfigFormatter & formatter)
+{
+    ConfigDataBuffer buffer;
+    config.serialize(buffer);
+    formatter.encode(buffer);
+    _os << buffer.getEncodedString();
+    return !_os.fail();
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/print/asciiconfigwriter.h b/config/src/vespa/config/print/asciiconfigwriter.h
new file mode 100644
index 00000000000..a22e3608855
--- /dev/null
+++ b/config/src/vespa/config/print/asciiconfigwriter.h
@@ -0,0 +1,20 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "configwriter.h"
+#include "configformatter.h"
+#include <vespa/vespalib/stllike/asciistream.h>
+
+namespace config {
+
+class AsciiConfigWriter : public ConfigWriter {
+public:
+    AsciiConfigWriter(vespalib::asciistream & os);
+    bool write(const ConfigInstance & config);
+    bool write(const ConfigInstance & config, const ConfigFormatter & formatter);
+private:
+    vespalib::asciistream & _os;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/print/configdatabuffer.h b/config/src/vespa/config/print/configdatabuffer.h
new file mode 100644
index 00000000000..ff485a19058
--- /dev/null
+++ b/config/src/vespa/config/print/configdatabuffer.h
@@ -0,0 +1,25 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/data/slime/slime.h>
+#include <vespa/vespalib/stllike/string.h>
+
+namespace config {
+
+/**
+ * Simple data container for slime object.
+ */
+class ConfigDataBuffer
+{
+public:
+    vespalib::Slime & slimeObject() { return _slime; }
+    const vespalib::Slime & slimeObject() const { return _slime; }
+    const vespalib::string & getEncodedString() const { return _encoded; }
+    void setEncodedString(const vespalib::string & encoded) { _encoded = encoded; }
+private:
+    vespalib::Slime _slime;
+    vespalib::string _encoded;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/print/configformatter.h b/config/src/vespa/config/print/configformatter.h
new file mode 100644
index 00000000000..f8fc1d8134b
--- /dev/null
+++ b/config/src/vespa/config/print/configformatter.h
@@ -0,0 +1,34 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "configdatabuffer.h"
+
+namespace config {
+
+/**
+ * Interface used by all config formatters. A config formatter is capable of
+ * encoding and decoding into any kind of format that can be put into a string.
+ */
+class ConfigFormatter {
+public:
+    /**
+     * Encode the slime object in a config data buffer, and put it into its
+     * string.
+     *
+     * @param buffer A ConfigDataBuffer containing a slime object that should be
+     *               encoded.
+     */
+    virtual void encode(ConfigDataBuffer & buffer) const = 0;
+
+    /**
+     * Decode a string in the config data buffer and populate its slime object.
+     *
+     * @param buffer A ConfigDataBuffer containing a string of the config.
+     */
+    virtual size_t decode(ConfigDataBuffer & buffer) const = 0;
+
+    virtual ~ConfigFormatter() { }
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/print/configreader.h b/config/src/vespa/config/print/configreader.h
new file mode 100644
index 00000000000..84789c1b485
--- /dev/null
+++ b/config/src/vespa/config/print/configreader.h
@@ -0,0 +1,26 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "configformatter.h"
+
+namespace config {
+
+/**
+ * Interface implemented by all classes capable of reading config of a specific
+ * type.
+ */
+template <typename ConfigType>
+class ConfigReader {
+public:
+    /**
+     * Read a config using a provided formatter, and return the correct type.
+     *
+     * @param formatter Something implementing ConfigFormatter interface.
+     * @return Instance of correct type.
+     */
+    virtual std::unique_ptr<ConfigType> read(const ConfigFormatter & formatter) = 0;
+    virtual ~ConfigReader() { }
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/print/configsnapshotreader.h b/config/src/vespa/config/print/configsnapshotreader.h
new file mode 100644
index 00000000000..c5fd416cace
--- /dev/null
+++ b/config/src/vespa/config/print/configsnapshotreader.h
@@ -0,0 +1,24 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/retriever/configsnapshot.h>
+
+namespace config {
+
+/**
+ * Interface implemented by all classes capable of reading config of a specific
+ * type.
+ */
+class ConfigSnapshotReader {
+public:
+    /**
+     * Read a config snapshot.
+     *
+     * @return Snapshot containing the configs.
+     */
+    virtual ConfigSnapshot read() = 0;
+    virtual ~ConfigSnapshotReader() { }
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/print/configsnapshotwriter.h b/config/src/vespa/config/print/configsnapshotwriter.h
new file mode 100644
index 00000000000..103668b82a8
--- /dev/null
+++ b/config/src/vespa/config/print/configsnapshotwriter.h
@@ -0,0 +1,25 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/retriever/configsnapshot.h>
+
+namespace config {
+
+/**
+ * Interface for classes capable of writing a config snapshots somewhere.
+ */
+class ConfigSnapshotWriter {
+public:
+    /**
+     * Write this config snapshot to a place decided by the implementer of this
+     * class.
+     *
+     * @param config The config snapshot to write.
+     * @return true if successful, false if not.
+     */
+    virtual bool write(const ConfigSnapshot & snapshot) = 0;
+    virtual ~ConfigSnapshotWriter() { }
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/print/configwriter.h b/config/src/vespa/config/print/configwriter.h
new file mode 100644
index 00000000000..782a1e57dab
--- /dev/null
+++ b/config/src/vespa/config/print/configwriter.h
@@ -0,0 +1,34 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/configgen/configinstance.h>
+#include "configformatter.h"
+
+namespace config {
+
+/**
+ * Interface for classes capable of writing a config instance somewhere.
+ */
+class ConfigWriter {
+public:
+    /**
+     * Write this config instance to a place decided by the implementer of this
+     * class.
+     *
+     * @param config The config instance to write.
+     */
+    virtual bool write(const ConfigInstance & config) = 0;
+
+    /**
+     * Write this config instance to a place decided by the implementer of this
+     * class. The provided formatter decides the format of the output.
+     *
+     * @param config The config instance to write.
+     * @param formatter The config formatter to use for formatting config.
+     */
+    virtual bool write(const ConfigInstance & config, const ConfigFormatter & formatter) = 0;
+    virtual ~ConfigWriter() { }
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/print/fileconfigformatter.cpp b/config/src/vespa/config/print/fileconfigformatter.cpp
new file mode 100644
index 00000000000..4c9c96f06c4
--- /dev/null
+++ b/config/src/vespa/config/print/fileconfigformatter.cpp
@@ -0,0 +1,236 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/fastos/fastos.h>
+#include <cmath>
+#include <stack>
+#include <vector>
+#include "fileconfigformatter.h"
+#include <vespa/vespalib/stllike/asciistream.h>
+#include <vespa/vespalib/util/exceptions.h>
+
+using namespace vespalib::slime::convenience;
+
+using vespalib::slime::ArrayTraverser;
+using vespalib::slime::ObjectTraverser;
+using vespalib::slime::BufferedOutput;
+using vespalib::slime::SimpleBuffer;
+using vespalib::slime::Output;
+
+namespace config {
+    void doEncode(ConfigDataBuffer & buffer, Output & output);
+}
+
+namespace {
+
+struct ConfigEncoder : public ArrayTraverser,
+                       public ObjectTraverser
+{
+    BufferedOutput &out;
+    int level;
+    bool head;
+    std::vector<std::string> prefixList;
+
+    ConfigEncoder(BufferedOutput &out_in)
+        : out(out_in), level(0), head(true) {}
+
+    void printPrefix() {
+        for (size_t i = 0; i < prefixList.size(); i++) {
+            out.printf("%s", prefixList[i].c_str());
+        }
+    }
+
+    void encodeBOOL(bool value) {
+        if (value) {
+            out.printf("true");
+        } else {
+            out.printf("false");
+        }
+    }
+    void encodeLONG(int64_t value) {
+        out.printf("%ld", value);
+    }
+    void encodeDOUBLE(double value) {
+        out.printf("%g", value);
+    }
+    void encodeSTRINGNOQUOTE(const Memory &memory) {
+        const char *hex = "0123456789ABCDEF";
+        char *p = out.reserve(memory.size * 6);
+        size_t len = 0;
+        const char *pos = memory.data;
+        const char *end = memory.data + memory.size;
+        for (; pos < end; ++pos) {
+            uint8_t c = *pos;
+            switch(c) {
+            case '"':  *p++ = '\\'; *p++ = '"';  len += 2; break;
+            case '\\': *p++ = '\\'; *p++ = '\\'; len += 2; break;
+            case '\b': *p++ = '\\'; *p++ = 'b';  len += 2; break;
+            case '\f': *p++ = '\\'; *p++ = 'f';  len += 2; break;
+            case '\n': *p++ = '\\'; *p++ = 'n';  len += 2; break;
+            case '\r': *p++ = '\\'; *p++ = 'r';  len += 2; break;
+            case '\t': *p++ = '\\'; *p++ = 't';  len += 2; break;
+            default:
+                if (c > 0x1f) {
+                    *p++ = c; ++len;
+                } else { // requires escaping according to RFC 4627
+                    *p++ = '\\'; *p++ = 'u'; *p++ = '0'; *p++ = '0';
+                    *p++ = hex[(c >> 4) & 0xf]; *p++ = hex[c & 0xf];
+                    len += 6;
+                }
+            }
+        }
+        out.commit(len);
+    }
+    void encodeSTRING(const Memory &memory) {
+        out.writeByte('\"');
+        encodeSTRINGNOQUOTE(memory);
+        out.writeByte('\"');
+    }
+    void encodeARRAY(const Inspector &inspector) {
+        ArrayTraverser &array_traverser = *this;
+        inspector.traverse(array_traverser);
+    }
+    void encodeMAP(const Inspector & inspector) {
+        for (size_t i = 0; i < inspector.children(); i++) {
+            const Inspector & child(inspector[i]);
+            vespalib::asciistream ss;
+            ss << "{\"" << child["key"].asString().make_string() << "\"}";
+            prefixList.push_back(ss.str());
+            encodeMAPEntry(child);
+            prefixList.pop_back();
+        }
+    }
+    void encodeMAPEntry(const Inspector & inspector) {
+        if (inspector["type"].valid()) {
+            std::string type(inspector["type"].asString().make_string());
+            if (type.compare("struct") == 0) {
+                prefixList.push_back(".");
+                encodeOBJECT(inspector["value"]);
+                prefixList.pop_back();
+            } else {
+                printPrefix();
+                out.writeByte(' ');
+                if (type.compare("enum") == 0) encodeSTRINGNOQUOTE(inspector["value"].asString());
+                else encodeValue(inspector["value"]);
+                out.writeByte('\n');
+            }
+        }
+    }
+    void encodeOBJECT(const Inspector &inspector) {
+        ObjectTraverser &object_traverser = *this;
+        inspector.traverse(object_traverser);
+    }
+    void encodeValue(const Inspector &inspector) {
+        switch (inspector.type().getId()) {
+        case vespalib::slime::BOOL::ID:   return encodeBOOL(inspector.asBool());
+        case vespalib::slime::LONG::ID:   return encodeLONG(inspector.asLong());
+        case vespalib::slime::DOUBLE::ID: return encodeDOUBLE(inspector.asDouble());
+        case vespalib::slime::STRING::ID: return encodeSTRING(inspector.asString());
+        case vespalib::slime::ARRAY::ID:  return encodeARRAY(inspector);
+        case vespalib::slime::OBJECT::ID: return encodeOBJECT(inspector);
+        case vespalib::slime::NIX::ID: return;
+        }
+        abort(); // should not be reached
+    }
+    virtual void entry(size_t idx, const Inspector &inspector);
+    virtual void field(const Memory &symbol_name, const Inspector &inspector);
+
+    static void encode(Inspector & root, BufferedOutput &out) {
+        ConfigEncoder encoder(out);
+        encoder.encodeValue(root);
+    }
+};
+
+void
+ConfigEncoder::entry(size_t index, const Inspector &inspector)
+{
+    if (inspector["type"].valid()) {
+        std::string type(inspector["type"].asString().make_string());
+        if (type.compare("array") == 0) {
+            vespalib::asciistream ss;
+            ss << "[" << index << "]";
+            prefixList.push_back(ss.str());
+            encodeARRAY(inspector["value"]);
+            prefixList.pop_back();
+        } else if (type.compare("struct") == 0) {
+            vespalib::asciistream ss;
+            ss << "[" << index << "].";
+            prefixList.push_back(ss.str());
+            encodeOBJECT(inspector["value"]);
+            prefixList.pop_back();
+        } else {
+            printPrefix();
+            out.writeByte('[');
+            encodeLONG(index);
+            out.writeByte(']');
+            out.writeByte(' ');
+
+            if (type.compare("enum") == 0) encodeSTRINGNOQUOTE(inspector["value"].asString());
+            else encodeValue(inspector["value"]);
+            out.writeByte('\n');
+        }
+    }
+}
+
+void
+ConfigEncoder::field(const Memory &symbol_name, const Inspector &inspector)
+{
+    if (inspector["type"].valid()) {
+        std::string type(inspector["type"].asString().make_string());
+        if (type.compare("array") == 0) {
+            size_t len = inspector["value"].children();
+            if (len > 0) {
+                prefixList.push_back(symbol_name.make_string());
+                encodeARRAY(inspector["value"]);
+                prefixList.pop_back();
+            }
+        } else if (type.compare("map") == 0) {
+            size_t len = inspector["value"].children();
+            if (len > 0) {
+                prefixList.push_back(symbol_name.make_string());
+                encodeMAP(inspector["value"]);
+                prefixList.pop_back();
+            }
+        } else if (type.compare("struct") == 0) {
+            prefixList.push_back(symbol_name.make_string() + ".");
+            encodeOBJECT(inspector["value"]);
+            prefixList.pop_back();
+        } else {
+            printPrefix();
+            encodeSTRINGNOQUOTE(symbol_name);
+            out.writeByte(' ');
+
+            if (type.compare("enum") == 0) encodeSTRINGNOQUOTE(inspector["value"].asString());
+            else encodeValue(inspector["value"]);
+            out.writeByte('\n');
+        }
+    }
+}
+
+}
+
+namespace config {
+
+void
+doEncode(ConfigDataBuffer & buffer, Output & output)
+{
+    BufferedOutput out(output);
+    ConfigEncoder::encode(buffer.slimeObject().get()["configPayload"], out);
+}
+
+void
+FileConfigFormatter::encode(ConfigDataBuffer & buffer) const
+{
+    SimpleBuffer buf;
+    doEncode(buffer, buf);
+    buffer.setEncodedString(buf.get().make_string());
+}
+
+size_t
+FileConfigFormatter::decode(ConfigDataBuffer & buffer) const
+{
+    (void) buffer;
+    throw vespalib::IllegalArgumentException("Reading cfg format is not supported");
+    return 0;
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/print/fileconfigformatter.h b/config/src/vespa/config/print/fileconfigformatter.h
new file mode 100644
index 00000000000..68476bf95b5
--- /dev/null
+++ b/config/src/vespa/config/print/fileconfigformatter.h
@@ -0,0 +1,21 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "configformatter.h"
+
+namespace config {
+
+/**
+ * Formatter capable of encoding config into old config format. Decoding is not
+ * supported.
+ */
+class FileConfigFormatter : public ConfigFormatter {
+public:
+    // Inherits ConfigFormatter
+    void encode(ConfigDataBuffer & buffer) const;
+    // Inherits ConfigFormatter
+    size_t decode(ConfigDataBuffer & buffer) const;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/print/fileconfigreader.h b/config/src/vespa/config/print/fileconfigreader.h
new file mode 100644
index 00000000000..86ab43dcfc5
--- /dev/null
+++ b/config/src/vespa/config/print/fileconfigreader.h
@@ -0,0 +1,35 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <sstream>
+#include <fstream>
+#include <vespa/vespalib/stllike/asciistream.h>
+#include <vespa/config/common/misc.h>
+#include <vespa/config/common/configvalue.h>
+#include <vespa/vespalib/util/exceptions.h>
+#include "configreader.h"
+
+namespace config {
+
+template <typename ConfigType>
+class FileConfigReader : public ConfigReader<ConfigType> {
+public:
+    FileConfigReader(const vespalib::string & fileName);
+
+    // Implements ConfigReader
+    std::unique_ptr<ConfigType> read(const ConfigFormatter & formatter);
+
+    /**
+     * Read config from this file using old config format.
+     *
+     * @return An instance of the correct type.
+     */
+    std::unique_ptr<ConfigType> read();
+private:
+    const vespalib::string _fileName;
+};
+
+} // namespace config
+
+#include "fileconfigreader.hpp"
+
diff --git a/config/src/vespa/config/print/fileconfigreader.hpp b/config/src/vespa/config/print/fileconfigreader.hpp
new file mode 100644
index 00000000000..4731b62047a
--- /dev/null
+++ b/config/src/vespa/config/print/fileconfigreader.hpp
@@ -0,0 +1,42 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+namespace config {
+
+template <typename ConfigType>
+FileConfigReader<ConfigType>::FileConfigReader(const vespalib::string & fileName)
+    : _fileName(fileName)
+{
+}
+
+template <typename ConfigType>
+std::unique_ptr<ConfigType>
+FileConfigReader<ConfigType>::read(const ConfigFormatter & formatter)
+{
+    ConfigDataBuffer buffer;
+    std::ifstream file(_fileName.c_str());
+    if (!file.is_open())
+        throw ConfigReadException("error: unable to read file '%s'", _fileName.c_str());
+
+    std::stringstream buf;
+    buf << file.rdbuf();
+    buffer.setEncodedString(buf.str());
+    formatter.decode(buffer);
+    return std::unique_ptr<ConfigType>(new ConfigType(buffer));
+}
+
+template <typename ConfigType>
+std::unique_ptr<ConfigType>
+FileConfigReader<ConfigType>::read()
+{
+    std::vector<vespalib::string> lines;
+    std::ifstream f(_fileName.c_str());
+    if (f.fail())
+        throw vespalib::IllegalArgumentException(std::string("Unable to open file ") + _fileName);
+    std::string line;
+    while (getline(f, line)) {
+        lines.push_back(line);
+    }
+    return std::unique_ptr<ConfigType>(new ConfigType(ConfigValue(lines, calculateContentMd5(lines))));
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/print/fileconfigsnapshotreader.cpp b/config/src/vespa/config/print/fileconfigsnapshotreader.cpp
new file mode 100644
index 00000000000..0cc7fe9fe38
--- /dev/null
+++ b/config/src/vespa/config/print/fileconfigsnapshotreader.cpp
@@ -0,0 +1,35 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <fstream>
+#include <sstream>
+#include "fileconfigsnapshotreader.h"
+#include "jsonconfigformatter.h"
+#include <iostream>
+
+namespace config {
+
+FileConfigSnapshotReader::FileConfigSnapshotReader(const vespalib::string & fileName)
+    : _fileName(fileName)
+{
+}
+
+ConfigSnapshot
+FileConfigSnapshotReader::read()
+{
+    std::ifstream file(_fileName.c_str());
+    if (!file.is_open())
+        throw ConfigReadException("error: unable to read file '%s'", _fileName.c_str());
+
+    std::stringstream buf;
+    buf << file.rdbuf();
+
+    ConfigDataBuffer buffer;
+    buffer.setEncodedString(buf.str());
+    JsonConfigFormatter formatter(true);
+    formatter.decode(buffer);
+    ConfigSnapshot snapshot;
+    snapshot.deserialize(buffer);
+    return snapshot;
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/print/fileconfigsnapshotreader.h b/config/src/vespa/config/print/fileconfigsnapshotreader.h
new file mode 100644
index 00000000000..fdf3dbd303c
--- /dev/null
+++ b/config/src/vespa/config/print/fileconfigsnapshotreader.h
@@ -0,0 +1,27 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+#include "configsnapshotreader.h"
+
+namespace config {
+
+/**
+ * Read config snapshots from file.
+ */
+class FileConfigSnapshotReader : public ConfigSnapshotReader {
+public:
+    FileConfigSnapshotReader(const vespalib::string & fileName);
+
+    /**
+     * Read a config snapshot.
+     *
+     * @return Snapshot containing the configs.
+     */
+    ConfigSnapshot read();
+private:
+    const vespalib::string _fileName;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/print/fileconfigsnapshotwriter.cpp b/config/src/vespa/config/print/fileconfigsnapshotwriter.cpp
new file mode 100644
index 00000000000..de5c3af065d
--- /dev/null
+++ b/config/src/vespa/config/print/fileconfigsnapshotwriter.cpp
@@ -0,0 +1,29 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <fstream>
+#include "fileconfigsnapshotwriter.h"
+#include "jsonconfigformatter.h"
+
+namespace config {
+
+FileConfigSnapshotWriter::FileConfigSnapshotWriter(const vespalib::string & fileName)
+    : _fileName(fileName)
+{
+}
+
+bool
+FileConfigSnapshotWriter::write(const ConfigSnapshot & snapshot)
+{
+    std::ofstream file(_fileName.c_str());
+    if (!file.is_open())
+        throw ConfigWriteException("error: could not open output file '%s'\n", _fileName.c_str());
+
+    ConfigDataBuffer buffer;
+    snapshot.serialize(buffer);
+    JsonConfigFormatter formatter(true);
+    formatter.encode(buffer);
+    file << buffer.getEncodedString();
+    return !file.fail();
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/print/fileconfigsnapshotwriter.h b/config/src/vespa/config/print/fileconfigsnapshotwriter.h
new file mode 100644
index 00000000000..104966827be
--- /dev/null
+++ b/config/src/vespa/config/print/fileconfigsnapshotwriter.h
@@ -0,0 +1,21 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+#include "configsnapshotwriter.h"
+
+namespace config {
+
+/**
+ * Write a config snapshot to a file.
+ */
+class FileConfigSnapshotWriter : public ConfigSnapshotWriter {
+public:
+    FileConfigSnapshotWriter(const vespalib::string & fileName);
+    bool write(const ConfigSnapshot & snapshot);
+private:
+    const vespalib::string _fileName;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/print/fileconfigwriter.cpp b/config/src/vespa/config/print/fileconfigwriter.cpp
new file mode 100644
index 00000000000..fc817f9e290
--- /dev/null
+++ b/config/src/vespa/config/print/fileconfigwriter.cpp
@@ -0,0 +1,32 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <fstream>
+#include "fileconfigwriter.h"
+#include "fileconfigformatter.h"
+#include "ostreamconfigwriter.h"
+#include <vespa/config/common/exceptions.h>
+
+namespace config {
+
+FileConfigWriter::FileConfigWriter(const vespalib::string & fileName)
+    : _fileName(fileName)
+{
+}
+
+bool
+FileConfigWriter::write(const ConfigInstance & config)
+{
+    return write(config, FileConfigFormatter());
+}
+
+bool
+FileConfigWriter::write(const ConfigInstance & config, const ConfigFormatter & formatter)
+{
+    std::ofstream file(_fileName.c_str());
+    if (!file.is_open())
+        throw ConfigWriteException("error: could not open output file: '%s'\n", _fileName.c_str());
+    OstreamConfigWriter osw(file);
+    return osw.write(config, formatter);
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/print/fileconfigwriter.h b/config/src/vespa/config/print/fileconfigwriter.h
new file mode 100644
index 00000000000..b79f7456199
--- /dev/null
+++ b/config/src/vespa/config/print/fileconfigwriter.h
@@ -0,0 +1,24 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+#include "configwriter.h"
+#include "configformatter.h"
+
+namespace config {
+
+/**
+ * Writes a config to file, optionally using a ConfigFormatter for formatting.
+ */
+class FileConfigWriter : public ConfigWriter {
+public:
+    FileConfigWriter(const vespalib::string & fileName);
+    // Implements ConfigWriter
+    bool write(const ConfigInstance & config);
+    bool write(const ConfigInstance & config, const ConfigFormatter & formatter);
+private:
+    const vespalib::string _fileName;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/print/istreamconfigreader.h b/config/src/vespa/config/print/istreamconfigreader.h
new file mode 100644
index 00000000000..b2446104419
--- /dev/null
+++ b/config/src/vespa/config/print/istreamconfigreader.h
@@ -0,0 +1,27 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <istream>
+#include "configreader.h"
+#include "configformatter.h"
+
+namespace config {
+
+/**
+ * Read a config from istream
+ */
+template <typename ConfigType>
+class IstreamConfigReader : public ConfigReader<ConfigType>
+{
+public:
+    IstreamConfigReader(std::istream & is);
+    std::unique_ptr<ConfigType> read();
+    std::unique_ptr<ConfigType> read(const ConfigFormatter & formatter);
+private:
+    std::istream & _is;
+};
+
+} // namespace config
+
+#include "istreamconfigreader.hpp"
+
diff --git a/config/src/vespa/config/print/istreamconfigreader.hpp b/config/src/vespa/config/print/istreamconfigreader.hpp
new file mode 100644
index 00000000000..2e43fd229e3
--- /dev/null
+++ b/config/src/vespa/config/print/istreamconfigreader.hpp
@@ -0,0 +1,35 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+namespace config {
+
+template <typename ConfigType>
+IstreamConfigReader<ConfigType>::IstreamConfigReader(std::istream & is)
+    : _is(is)
+{
+}
+
+template <typename ConfigType>
+std::unique_ptr<ConfigType>
+IstreamConfigReader<ConfigType>::read(const ConfigFormatter & formatter)
+{
+    ConfigDataBuffer buffer;
+    std::stringstream buf;
+    buf << _is.rdbuf();
+    buffer.setEncodedString(buf.str());
+    formatter.decode(buffer);
+    return std::unique_ptr<ConfigType>(new ConfigType(buffer));
+}
+
+template <typename ConfigType>
+std::unique_ptr<ConfigType>
+IstreamConfigReader<ConfigType>::read()
+{
+    std::vector<vespalib::string> lines;
+    std::string line;
+    while (getline(_is, line)) {
+        lines.push_back(line);
+    }
+    return std::unique_ptr<ConfigType>(new ConfigType(ConfigValue(lines, calculateContentMd5(lines))));
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/print/jsonconfigformatter.cpp b/config/src/vespa/config/print/jsonconfigformatter.cpp
new file mode 100644
index 00000000000..998895eeac4
--- /dev/null
+++ b/config/src/vespa/config/print/jsonconfigformatter.cpp
@@ -0,0 +1,39 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/fastos/fastos.h>
+#include <cmath>
+#include <stack>
+#include <vector>
+#include "jsonconfigformatter.h"
+#include <vespa/vespalib/stllike/asciistream.h>
+#include <vespa/vespalib/data/slime/json_format.h>
+
+using namespace vespalib::slime::convenience;
+
+using vespalib::slime::SimpleBuffer;
+using vespalib::slime::Output;
+using vespalib::slime::JsonFormat;
+
+namespace config {
+
+JsonConfigFormatter::JsonConfigFormatter(bool compact)
+    : _compact(compact)
+{
+}
+
+void
+JsonConfigFormatter::encode(ConfigDataBuffer & buffer) const
+{
+    SimpleBuffer buf;
+    JsonFormat::encode(buffer.slimeObject(), buf, _compact);
+    buffer.setEncodedString(buf.get().make_string());
+}
+
+size_t
+JsonConfigFormatter::decode(ConfigDataBuffer & buffer) const
+{
+    std::string ref(buffer.getEncodedString());
+    return JsonFormat::decode(ref, buffer.slimeObject());
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/print/jsonconfigformatter.h b/config/src/vespa/config/print/jsonconfigformatter.h
new file mode 100644
index 00000000000..f1b981870b2
--- /dev/null
+++ b/config/src/vespa/config/print/jsonconfigformatter.h
@@ -0,0 +1,23 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "configformatter.h"
+
+namespace config {
+
+/**
+ * Formatter capable of encoding and decoding config as json.
+ */
+class JsonConfigFormatter : public ConfigFormatter {
+public:
+    JsonConfigFormatter(bool compact = false);
+    // Inherits ConfigFormatter
+    void encode(ConfigDataBuffer & buffer) const;
+    // Inherits ConfigFormatter
+    size_t decode(ConfigDataBuffer & buffer) const;
+private:
+    const bool _compact;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/print/ostreamconfigwriter.cpp b/config/src/vespa/config/print/ostreamconfigwriter.cpp
new file mode 100644
index 00000000000..eda15d9e2c0
--- /dev/null
+++ b/config/src/vespa/config/print/ostreamconfigwriter.cpp
@@ -0,0 +1,29 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "ostreamconfigwriter.h"
+#include "fileconfigformatter.h"
+
+namespace config {
+
+OstreamConfigWriter::OstreamConfigWriter(std::ostream & os)
+    : _os(os)
+{
+}
+
+bool
+OstreamConfigWriter::write(const ConfigInstance & config, const ConfigFormatter & formatter)
+{
+    ConfigDataBuffer buffer;
+    config.serialize(buffer);
+    formatter.encode(buffer);
+    _os << buffer.getEncodedString();
+    return !_os.fail();
+}
+
+bool
+OstreamConfigWriter::write(const ConfigInstance & config)
+{
+    return write(config, FileConfigFormatter());
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/print/ostreamconfigwriter.h b/config/src/vespa/config/print/ostreamconfigwriter.h
new file mode 100644
index 00000000000..fa211f9085f
--- /dev/null
+++ b/config/src/vespa/config/print/ostreamconfigwriter.h
@@ -0,0 +1,24 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <ostream>
+#include "configwriter.h"
+#include "configformatter.h"
+
+namespace config {
+
+/**
+ * Write config to an ostream.
+ */
+class OstreamConfigWriter : public ConfigWriter
+{
+public:
+    OstreamConfigWriter(std::ostream & os);
+    bool write(const ConfigInstance & config);
+    bool write(const ConfigInstance & config, const ConfigFormatter & formatter);
+private:
+    std::ostream & _os;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/raw/.gitignore b/config/src/vespa/config/raw/.gitignore
new file mode 100644
index 00000000000..7e7c0fe7fae
--- /dev/null
+++ b/config/src/vespa/config/raw/.gitignore
@@ -0,0 +1,2 @@
+/.depend
+/Makefile
diff --git a/config/src/vespa/config/raw/CMakeLists.txt b/config/src/vespa/config/raw/CMakeLists.txt
new file mode 100644
index 00000000000..f5d2ec9f064
--- /dev/null
+++ b/config/src/vespa/config/raw/CMakeLists.txt
@@ -0,0 +1,7 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_library(config_raw OBJECT
+    SOURCES
+    rawsource.cpp
+    rawsourcefactory.cpp
+    DEPENDS
+)
diff --git a/config/src/vespa/config/raw/rawsource.cpp b/config/src/vespa/config/raw/rawsource.cpp
new file mode 100644
index 00000000000..3cb3003cb7e
--- /dev/null
+++ b/config/src/vespa/config/raw/rawsource.cpp
@@ -0,0 +1,42 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/config/common/misc.h>
+#include "rawsource.h"
+#include <vespa/vespalib/stllike/asciistream.h>
+
+namespace config {
+
+
+RawSource::RawSource(const IConfigHolder::SP & holder, const vespalib::string & payload)
+    : _holder(holder),
+      _payload(payload)
+{
+}
+
+void
+RawSource::getConfig()
+{
+    auto lines(readConfig());
+    ConfigValue value(lines, calculateContentMd5(lines));
+    _holder->handle(ConfigUpdate::UP(new ConfigUpdate(value, true, 1)));
+}
+
+void
+RawSource::reload(int64_t generation)
+{
+    (void) generation;
+}
+
+void
+RawSource::close()
+{
+}
+
+std::vector<vespalib::string>
+RawSource::readConfig()
+{
+    vespalib::asciistream is(_payload);
+    return is.getlines();
+}
+
+}
diff --git a/config/src/vespa/config/raw/rawsource.h b/config/src/vespa/config/raw/rawsource.h
new file mode 100644
index 00000000000..b93e58c2111
--- /dev/null
+++ b/config/src/vespa/config/raw/rawsource.h
@@ -0,0 +1,27 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/source.h>
+#include <vespa/config/common/iconfigholder.h>
+#include <vespa/vespalib/stllike/string.h>
+
+namespace config {
+
+/**
+ * Class for sending and receiving config request from a raw string.
+ */
+class RawSource : public Source {
+public:
+    RawSource(const IConfigHolder::SP & holder, const vespalib::string & payload);
+
+    void getConfig();
+    void reload(int64_t generation);
+    void close();
+private:
+    IConfigHolder::SP _holder;
+    std::vector<vespalib::string> readConfig();
+    const vespalib::string _payload;
+};
+
+}
+
diff --git a/config/src/vespa/config/raw/rawsourcefactory.cpp b/config/src/vespa/config/raw/rawsourcefactory.cpp
new file mode 100644
index 00000000000..c432c1db6dd
--- /dev/null
+++ b/config/src/vespa/config/raw/rawsourcefactory.cpp
@@ -0,0 +1,16 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/config/common/source.h>
+#include "rawsourcefactory.h"
+#include "rawsource.h"
+
+namespace config {
+
+Source::UP
+RawSourceFactory::createSource(const IConfigHolder::SP & holder, const ConfigKey & key) const
+{
+    (void) key;
+    return Source::UP(new RawSource(holder, _payload));
+}
+
+}
diff --git a/config/src/vespa/config/raw/rawsourcefactory.h b/config/src/vespa/config/raw/rawsourcefactory.h
new file mode 100644
index 00000000000..e994bb54ba8
--- /dev/null
+++ b/config/src/vespa/config/raw/rawsourcefactory.h
@@ -0,0 +1,23 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/sourcefactory.h>
+
+namespace config {
+
+/**
+ * Factory for RawSource
+ */
+class RawSourceFactory : public SourceFactory {
+public:
+    RawSourceFactory(const vespalib::string & payload)
+        : _payload(payload)
+    { }
+
+    Source::UP createSource(const IConfigHolder::SP & holder, const ConfigKey & key) const;
+private:
+    const vespalib::string _payload;
+};
+
+}
+
diff --git a/config/src/vespa/config/retriever/.gitignore b/config/src/vespa/config/retriever/.gitignore
new file mode 100644
index 00000000000..cd4bc99c04f
--- /dev/null
+++ b/config/src/vespa/config/retriever/.gitignore
@@ -0,0 +1,2 @@
+/Makefile
+/.depend
diff --git a/config/src/vespa/config/retriever/CMakeLists.txt b/config/src/vespa/config/retriever/CMakeLists.txt
new file mode 100644
index 00000000000..03a6d30ffa2
--- /dev/null
+++ b/config/src/vespa/config/retriever/CMakeLists.txt
@@ -0,0 +1,12 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_library(config_retriever OBJECT
+    SOURCES
+    configretriever.cpp
+    configsnapshot.cpp
+    genericconfigsubscriber.cpp
+    fixedconfigsubscriber.cpp
+    configkeyset.cpp
+    simpleconfigretriever.cpp
+    simpleconfigurer.cpp
+    DEPENDS
+)
diff --git a/config/src/vespa/config/retriever/configkeyset.cpp b/config/src/vespa/config/retriever/configkeyset.cpp
new file mode 100644
index 00000000000..d64c1a4b9ed
--- /dev/null
+++ b/config/src/vespa/config/retriever/configkeyset.cpp
@@ -0,0 +1,14 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "configkeyset.h"
+
+namespace config {
+
+ConfigKeySet &
+ConfigKeySet::add(const ConfigKeySet & configKeySet)
+{
+    insert(configKeySet.begin(), configKeySet.end());
+    return *this;
+}
+
+}
diff --git a/config/src/vespa/config/retriever/configkeyset.h b/config/src/vespa/config/retriever/configkeyset.h
new file mode 100644
index 00000000000..52ab9962230
--- /dev/null
+++ b/config/src/vespa/config/retriever/configkeyset.h
@@ -0,0 +1,47 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+#include <vespa/config/common/configkey.h>
+#include <set>
+
+namespace config {
+
+/**
+ * A ConfigKeySet is a set of ConfigKey objects. Each ConfigKey represents a
+ * config by its definition name, version, md5, namespace and config id.
+ */
+class ConfigKeySet : public std::set<ConfigKey>
+{
+public:
+    /**
+     * Add a new config type with a config id to this set.
+     *
+     * @param configId the configId of this key.
+     * @return *this for chaining.
+     */
+    template <typename... ConfigTypes>
+    ConfigKeySet & add(const vespalib::string & configId);
+
+    /**
+     * Add add another key set to this set.
+     *
+     * @param configKeySet The set to add.
+     * @return *this for chaining.
+     */
+    ConfigKeySet & add(const ConfigKeySet & configKeySet);
+private:
+    template<typename... ConfigTypes>
+    struct TypeTag {};
+
+    template<typename ConfigType>
+    void addImpl(const vespalib::string & configId, TypeTag<ConfigType>);
+
+    template<typename ConfigType, typename... ConfigTypes>
+    void addImpl(const vespalib::string & configId, TypeTag<ConfigType, ConfigTypes...>);
+};
+
+} // namespace config
+
+#include "configkeyset.hpp"
+
diff --git a/config/src/vespa/config/retriever/configkeyset.hpp b/config/src/vespa/config/retriever/configkeyset.hpp
new file mode 100644
index 00000000000..579fa454703
--- /dev/null
+++ b/config/src/vespa/config/retriever/configkeyset.hpp
@@ -0,0 +1,30 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+namespace config {
+
+
+template <typename... ConfigTypes>
+ConfigKeySet &
+ConfigKeySet::add(const vespalib::string & configId)
+{
+    addImpl(configId, TypeTag<ConfigTypes...>());
+    return *this;
+}
+
+template <typename ConfigType>
+void
+ConfigKeySet::addImpl(const vespalib::string & configId, TypeTag<ConfigType>)
+{
+    insert(ConfigKey::create<ConfigType>(configId));
+}
+
+template <typename ConfigType, typename... ConfigTypes>
+void
+ConfigKeySet::addImpl(const vespalib::string & configId, TypeTag<ConfigType, ConfigTypes...>)
+{
+    insert(ConfigKey::create<ConfigType>(configId));
+    addImpl(configId, TypeTag<ConfigTypes...>());
+}
+
+
+}
diff --git a/config/src/vespa/config/retriever/configretriever.cpp b/config/src/vespa/config/retriever/configretriever.cpp
new file mode 100644
index 00000000000..d09aaf0d332
--- /dev/null
+++ b/config/src/vespa/config/retriever/configretriever.cpp
@@ -0,0 +1,95 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+#include <vespa/config/common/exceptions.h>
+LOG_SETUP(".config.retriever.configretriever");
+#include "configretriever.h"
+
+namespace config {
+
+
+ConfigRetriever::ConfigRetriever(const ConfigKeySet & bootstrapSet,
+                                 const IConfigContext::SP & context,
+                                 int64_t subscribeTimeout)
+    : _bootstrapSubscriber(bootstrapSet, context, subscribeTimeout),
+      _configSubscriber(),
+      _lock(),
+      _subscriptionList(),
+      _lastKeySet(),
+      _context(context),
+      _closed(false),
+      _generation(-1),
+      _subscribeTimeout(subscribeTimeout),
+      _bootstrapRequired(true)
+{
+}
+
+ConfigSnapshot
+ConfigRetriever::getBootstrapConfigs(int timeoutInMillis)
+{
+    bool ret = _bootstrapSubscriber.nextGeneration(timeoutInMillis);
+    if (!ret) {
+        return ConfigSnapshot();
+    }
+    _bootstrapRequired = false;
+    return _bootstrapSubscriber.getConfigSnapshot();
+}
+
+ConfigSnapshot
+ConfigRetriever::getConfigs(const ConfigKeySet & keySet, int timeoutInMillis)
+{
+    if (_closed)
+        return ConfigSnapshot();
+    if (_bootstrapRequired) {
+        throw ConfigRuntimeException("Cannot change keySet until bootstrap getBootstrapConfigs() has been called");
+    }
+    assert(!keySet.empty());
+    if (keySet != _lastKeySet) {
+        _lastKeySet = keySet;
+        {
+            vespalib::LockGuard guard(_lock);
+            if (_closed)
+                return ConfigSnapshot();
+            _configSubscriber.reset(new GenericConfigSubscriber(_context));
+        }
+        _subscriptionList.clear();
+        for (ConfigKeySet::const_iterator it(keySet.begin()), mt(keySet.end()); it != mt; it++) {
+            _subscriptionList.push_back(_configSubscriber->subscribe(*it, _subscribeTimeout));
+        }
+    }
+    // Try update the subscribers generation if older than bootstrap
+    if (_configSubscriber->getGeneration() < _bootstrapSubscriber.getGeneration())
+        _configSubscriber->nextGeneration(timeoutInMillis);
+
+    // If we failed to get a new generation, the user should call us again.
+    if (_configSubscriber->getGeneration() < _bootstrapSubscriber.getGeneration()) {
+        return ConfigSnapshot();
+    }
+    // If we are not in sync, even though we got a new generation, we should get
+    // another bootstrap.
+    _bootstrapRequired = _configSubscriber->getGeneration() > _bootstrapSubscriber.getGeneration();
+    if (_bootstrapRequired)
+        return ConfigSnapshot();
+
+    _generation = _configSubscriber->getGeneration();
+    return ConfigSnapshot(_subscriptionList, _generation);
+}
+
+void
+ConfigRetriever::close()
+{
+    vespalib::LockGuard guard(_lock);
+    _closed = true;
+    _bootstrapSubscriber.close();
+    if (_configSubscriber.get() != NULL)
+        _configSubscriber->close();
+}
+
+bool
+ConfigRetriever::isClosed() const
+{
+    return (_closed);
+}
+
+}
diff --git a/config/src/vespa/config/retriever/configretriever.h b/config/src/vespa/config/retriever/configretriever.h
new file mode 100644
index 00000000000..8c09dd06ce6
--- /dev/null
+++ b/config/src/vespa/config/retriever/configretriever.h
@@ -0,0 +1,106 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/vespalib/stllike/string.h>
+#include <vespa/config/common/configkey.h>
+#include <vespa/config/subscription/configsubscription.h>
+#include "configkeyset.h"
+#include "configsnapshot.h"
+#include "genericconfigsubscriber.h"
+#include "fixedconfigsubscriber.h"
+
+namespace config {
+
+/**
+ * A ConfigRetriever is a helper class for retrieving a set of dynamically
+ * changing and depending configs. You should use this class whenever you have a
+ * set of bootstrap configs, and want to subscribe to a dynamically changing set
+ * of configs based on those.
+ *
+ * The retriever should be used from one thread only, but close can be called
+ * from another thread.
+ */
+class ConfigRetriever
+{
+public:
+    ConfigRetriever(const ConfigKeySet & bootstrapSet,
+                    const IConfigContext::SP & context,
+                    int64_t subscribeTimeout = DEFAULT_SUBSCRIBE_TIMEOUT);
+
+    /**
+     * Waits for the next generation of bootstrap configs to arrive, and returns
+     * them. If no new generation has arrived, return an empty snapshot.
+     *
+     * @param timeoutInMillis The timeout of the nextGeneration call, in
+     *                        milliseconds. Optional.
+     * @return a snapshot of bootstrap configs, empty if no new snapshot or
+     *         retriever has been closed.
+     * @throws ConfigTimeoutException if initial subscribe timed out.
+     */
+    ConfigSnapshot getBootstrapConfigs(int timeoutInMillis = DEFAULT_NEXTGENERATION_TIMEOUT);
+
+    /**
+     * Return the configs represented by a ConfigKeySet in a snapshot, and makes
+     * sure that it is in sync with the bootstrap config. If it is not, an empty
+     * snapshot is returned.
+     *
+     * @param keySet The set of configs that should be fetched. The set may only
+     *               change when bootstrap has been changed.
+     * @param timeoutInMillis The timeout, in milliseconds. Optional.
+     * @return a snapshot of configs corresponding to the keySet or
+     *         an empty snapshot if
+     *              a) retriever has been closed. The isClosed() method can be
+     *                 used to check for this condition.
+     *              b) no new generation was found, in which case getConfigs()
+     *                 should be called again.
+     *              c) generation is not in sync with bootstrap, in which case
+     *                 getBootstrapConfigs() must be called. The bootstrapRequired
+     *                 method can be used to check for this condition.
+     * @throws ConfigTimeoutException if resubscribe timed out.
+     */
+    ConfigSnapshot getConfigs(const ConfigKeySet & keySet, int timeoutInMillis = DEFAULT_NEXTGENERATION_TIMEOUT);
+
+    /**
+     * Close this retriever in order to shut down.
+     */
+    void close();
+
+    /**
+     * Check if this retriever is closed.
+     *
+     * @return true if closed, false if not.
+     */
+    bool isClosed() const;
+
+    /**
+     * Returns if a new bootstrap call is required.
+     *
+     * @return true if required, false if not.
+     */
+    bool bootstrapRequired() const { return _bootstrapRequired; }
+
+    /**
+     * Get the current generation of the configs managed by this retriever.
+     *
+     * @return the generation
+     */
+    int64_t getGeneration() const { return _generation; }
+
+    static const int DEFAULT_SUBSCRIBE_TIMEOUT = 60000;
+    static const int DEFAULT_NEXTGENERATION_TIMEOUT = 60000;
+private:
+    FixedConfigSubscriber _bootstrapSubscriber;
+    std::unique_ptr<GenericConfigSubscriber> _configSubscriber;
+    vespalib::Lock _lock;
+    std::vector<ConfigSubscription::SP> _subscriptionList;
+    ConfigKeySet _lastKeySet;
+    IConfigContext::SP _context;
+    std::unique_ptr<SourceSpec> _spec;
+    bool _closed;
+    int64_t _generation;
+    int64_t _subscribeTimeout;
+    bool _bootstrapRequired;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/retriever/configsnapshot.cpp b/config/src/vespa/config/retriever/configsnapshot.cpp
new file mode 100644
index 00000000000..d7041f3c680
--- /dev/null
+++ b/config/src/vespa/config/retriever/configsnapshot.cpp
@@ -0,0 +1,258 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "configsnapshot.h"
+#include <vespa/vespalib/stllike/asciistream.h>
+#include <vespa/config/common/misc.h>
+
+using vespalib::Slime;
+using vespalib::slime::Cursor;
+using vespalib::slime::Inspector;
+using vespalib::slime::Memory;
+
+namespace config {
+
+const int64_t ConfigSnapshot::SNAPSHOT_FORMAT_VERSION = 1;
+
+ConfigSnapshot::ConfigSnapshot()
+    : _valueMap(),
+      _generation(0)
+{}
+
+ConfigSnapshot::~ConfigSnapshot()
+{
+}
+
+ConfigSnapshot::ConfigSnapshot(const ConfigSnapshot & rhs) :
+    _valueMap(rhs._valueMap),
+    _generation(rhs._generation)
+{
+}
+
+ConfigSnapshot &
+ConfigSnapshot::operator = (const ConfigSnapshot & rhs)
+{
+    if (&rhs != this) {
+        ConfigSnapshot tmp(rhs);
+        tmp.swap(*this);
+    }
+    return *this;
+}
+
+void
+ConfigSnapshot::swap(ConfigSnapshot & rhs)
+{
+    _valueMap.swap(rhs._valueMap);
+    std::swap(_generation, rhs._generation);
+}
+
+ConfigSnapshot::ConfigSnapshot(const SubscriptionList & subscriptionList, int64_t generation)
+    : _valueMap(),
+      _generation(generation)
+{
+    for (SubscriptionList::const_iterator it(subscriptionList.begin()), mt(subscriptionList.end()); it != mt; it++) {
+        _valueMap[(*it)->getKey()] = Value((*it)->getLastGenerationChanged(), (*it)->getConfig());
+    }
+}
+
+ConfigSnapshot::ConfigSnapshot(const ValueMap & valueMap, int64_t generation)
+    : _valueMap(valueMap),
+      _generation(generation)
+{
+}
+
+ConfigSnapshot
+ConfigSnapshot::subset(const ConfigKeySet & keySet) const
+{
+    ValueMap subSet;
+    for (ConfigKeySet::const_iterator it(keySet.begin()), mt(keySet.end()); it != mt; it++) {
+        ValueMap::const_iterator found(_valueMap.find(*it));
+        if (found != _valueMap.end()) {
+            subSet[*it] = found->second;
+        }
+    }
+    return ConfigSnapshot(subSet, _generation);
+}
+
+int64_t ConfigSnapshot::getGeneration() const { return _generation; }
+size_t ConfigSnapshot::size() const { return _valueMap.size(); }
+bool ConfigSnapshot::empty() const { return _valueMap.empty(); }
+
+void
+ConfigSnapshot::serialize(ConfigDataBuffer & buffer) const
+{
+    Slime & slime(buffer.slimeObject());
+    Cursor & root(slime.setObject());
+    root.setDouble("version", SNAPSHOT_FORMAT_VERSION);
+
+    switch (SNAPSHOT_FORMAT_VERSION) {
+        case 1:
+            serializeV1(root);
+            break;
+        case 2:
+            serializeV2(root);
+            break;
+        default:
+            vespalib::asciistream ss;
+            ss << "Version '" << SNAPSHOT_FORMAT_VERSION << "' is not a valid version.";
+            throw ConfigWriteException(ss.str());
+    }
+}
+
+void
+ConfigSnapshot::serializeV1(Cursor & root) const
+{
+    root.setDouble("generation", _generation);
+    Cursor & snapshots(root.setArray("snapshots"));
+    for (ValueMap::const_iterator it(_valueMap.begin()), mt(_valueMap.end()); it != mt; it++) {
+        Cursor & snapshot(snapshots.addObject());
+        serializeKeyV1(snapshot.setObject("configKey"), it->first);
+        serializeValueV1(snapshot.setObject("configPayload"), it->second);
+    }
+}
+
+void
+ConfigSnapshot::serializeV2(Cursor & root) const
+{
+    root.setDouble("generation", _generation);
+    Cursor & snapshots(root.setArray("snapshots"));
+    for (ValueMap::const_iterator it(_valueMap.begin()), mt(_valueMap.end()); it != mt; it++) {
+        Cursor & snapshot(snapshots.addObject());
+        serializeKeyV1(snapshot.setObject("configKey"), it->first);
+        serializeValueV2(snapshot.setObject("configPayload"), it->second);
+    }
+}
+
+void
+ConfigSnapshot::serializeKeyV1(Cursor & cursor, const ConfigKey & key) const
+{
+    typedef std::vector<vespalib::string> SchemaVector;
+    cursor.setString("configId", Memory(key.getConfigId()));
+    cursor.setString("defName", Memory(key.getDefName()));
+    cursor.setString("defNamespace", Memory(key.getDefNamespace()));
+    cursor.setString("defMd5", Memory(key.getDefMd5()));
+    Cursor & defSchema(cursor.setArray("defSchema"));
+    const SchemaVector & vec(key.getDefSchema());
+    for (SchemaVector::const_iterator it(vec.begin()), mt(vec.end()); it != mt; it++) {
+        defSchema.addString(vespalib::slime::Memory(*it));
+    }
+}
+
+void
+ConfigSnapshot::serializeValueV1(Cursor & cursor, const Value & value) const
+{
+    cursor.setDouble("lastChanged", value.first);
+    value.second.serializeV1(cursor.setArray("lines"));
+}
+
+void
+ConfigSnapshot::serializeValueV2(Cursor & cursor, const Value & value) const
+{
+    cursor.setDouble("lastChanged", value.first);
+    cursor.setString("md5", Memory(value.second.getMd5()));
+    value.second.serializeV2(cursor.setObject("payload"));
+}
+
+void
+ConfigSnapshot::deserialize(const ConfigDataBuffer & buffer)
+{
+    const Slime & slime(buffer.slimeObject());
+    Inspector & inspector(slime.get());
+    int64_t version = static_cast<int64_t>(inspector["version"].asDouble());
+    switch (version) {
+    case 1:
+        deserializeV1(inspector);
+        break;
+    case 2:
+        deserializeV2(inspector);
+        break;
+    default:
+        vespalib::asciistream ss;
+        ss << "Version '" << version << "' is not a valid version.";
+        throw ConfigReadException(ss.str());
+    }
+}
+
+void
+ConfigSnapshot::deserializeV1(Inspector & root)
+{
+    _generation = static_cast<int64_t>(root["generation"].asDouble());
+    Inspector & snapshots(root["snapshots"]);
+    for (size_t i = 0; i < snapshots.children(); i++) {
+        Inspector & snapshot(snapshots[i]);
+        ConfigKey key(deserializeKeyV1(snapshot["configKey"]));
+        Value value(deserializeValueV1(snapshot["configPayload"]));
+        _valueMap[key] = value;
+    }
+}
+
+void
+ConfigSnapshot::deserializeV2(Inspector & root)
+{
+    _generation = static_cast<int64_t>(root["generation"].asDouble());
+    Inspector & snapshots(root["snapshots"]);
+    for (size_t i = 0; i < snapshots.children(); i++) {
+        Inspector & snapshot(snapshots[i]);
+        ConfigKey key(deserializeKeyV1(snapshot["configKey"]));
+        Value value(deserializeValueV2(snapshot["configPayload"]));
+        _valueMap[key] = value;
+    }
+}
+
+ConfigKey
+ConfigSnapshot::deserializeKeyV1(Inspector & inspector) const
+{
+    std::vector<vespalib::string> schema;
+    Inspector & s(inspector["defSchema"]);
+    for (size_t i = 0; i < s.children(); i++) {
+        schema.push_back(s[i].asString().make_string());
+    }
+    return ConfigKey(inspector["configId"].asString().make_string(),
+                     inspector["defName"].asString().make_string(),
+                     inspector["defNamespace"].asString().make_string(),
+                     inspector["defMd5"].asString().make_string(),
+                     schema);
+
+}
+
+std::pair<int64_t, ConfigValue>
+ConfigSnapshot::deserializeValueV1(Inspector & inspector) const
+{
+    std::vector<vespalib::string> payload;
+    int64_t lastChanged = static_cast<int64_t>(inspector["lastChanged"].asDouble());
+    Inspector & s(inspector["lines"]);
+    for (size_t i = 0; i < s.children(); i++) {
+        payload.push_back(s[i].asString().make_string());
+    }
+    return Value(lastChanged, ConfigValue(payload, calculateContentMd5(payload)));
+}
+
+namespace {
+
+class FixedPayload : public protocol::Payload {
+public:
+    const Inspector & getSlimePayload() const
+    {
+        return _data.get();
+    }
+
+    Slime & getData() {
+        return _data;
+    }
+private:
+    Slime _data;
+};
+
+}
+
+std::pair<int64_t, ConfigValue>
+ConfigSnapshot::deserializeValueV2(Inspector & inspector) const
+{
+    int64_t lastChanged = static_cast<int64_t>(inspector["lastChanged"].asDouble());
+    vespalib::string md5(inspector["md5"].asString().make_string());
+    FixedPayload * payload = new FixedPayload();
+    PayloadPtr data(payload);
+    copySlimeObject(inspector["payload"], payload->getData().setObject());
+    return Value(lastChanged, ConfigValue(data, md5));
+}
+
+}
diff --git a/config/src/vespa/config/retriever/configsnapshot.h b/config/src/vespa/config/retriever/configsnapshot.h
new file mode 100644
index 00000000000..344fc86929c
--- /dev/null
+++ b/config/src/vespa/config/retriever/configsnapshot.h
@@ -0,0 +1,123 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/subscription/configsubscription.h>
+#include <vespa/config/common/exceptions.h>
+#include <vespa/config/print/configdatabuffer.h>
+#include <vespa/vespalib/stllike/string.h>
+#include <map>
+#include "configkeyset.h"
+
+namespace config {
+
+/**
+ * A ConfigSnapshot contains a map of config keys to config instances. You may
+ * request an instance of a config by calling the getConfig method.
+ */
+class ConfigSnapshot
+{
+public:
+    typedef std::vector<ConfigSubscription::SP> SubscriptionList;
+
+    /**
+     * Construct an empty config snapshot.
+     */
+    ConfigSnapshot();
+    ~ConfigSnapshot();
+
+    ConfigSnapshot(const ConfigSnapshot & rhs);
+
+    /**
+     * Construct a config snapshot from a list of subscriptions and their
+     * current generation.
+     *
+     * @param subscriptionList A list of config subscriptions used to populate
+     *                         the snapshot.
+     * @param generation The latest generation of configs.
+     */
+    ConfigSnapshot(const SubscriptionList & subscriptionList, int64_t generation);
+
+    /**
+     * Instantiate one of the configs from this snapshot identified by its type
+     * and config id.
+     *
+     * @param configId The configId of the desired instance.
+     * @return an std::unqiue_ptr to an instance of this config.
+     * @throws InvalidConfigException if unable instantiate the given type or
+     *         parse config.
+     * @throws IllegalConfigKeyException if the config does not exist.
+     */
+    template <typename ConfigType>
+    std::unique_ptr<ConfigType> getConfig(const vespalib::string & configId) const;
+
+    /**
+     * Query snapshot to check if a config of type ConfigType and id configId is
+     * changed relative to a provided generation.
+     *
+     * @param configId The configId of the instance to check.
+     * @param currentGeneration The generation of the current active config in
+     *                          use by the caller.
+     * @return true if changed, false if not.
+     * @throws IllegalConfigKeyException if the config does not exist.
+     */
+    template <typename ConfigType>
+    bool isChanged(const vespalib::string & configId, int64_t currentGeneration) const;
+
+    ConfigSnapshot & operator = (const ConfigSnapshot & rhs);
+    void swap(ConfigSnapshot & rhs);
+
+    /**
+     * Query snapshot to check if a config of type ConfigType and id configId
+     * exists in this snapshot.
+     *
+     * @param configId The configId of the instance to check.
+     * @return true if exists, false if not.
+     */
+    template <typename ConfigType>
+    bool hasConfig(const vespalib::string & configId) const;
+
+    /**
+     * Create a new snapshot as a subset of this snapshot based on a set of keys.
+     * If a key does not exist in this snapshot, the new snapshot will not
+     * contain an entry for that key.
+     *
+     * @param keySet The keySet to use for selecting which configs to put in the
+     *               new snapshot.
+     * @return a new snapshot.
+     */
+    ConfigSnapshot subset(const ConfigKeySet & keySet) const;
+
+    int64_t getGeneration() const;
+    size_t size() const;
+    bool empty() const;
+
+    void serialize(ConfigDataBuffer & buffer) const;
+    void deserialize(const ConfigDataBuffer & buffer);
+private:
+    typedef std::pair<int64_t, ConfigValue> Value;
+    typedef std::map<ConfigKey, Value> ValueMap;
+    const static int64_t SNAPSHOT_FORMAT_VERSION;
+
+    ConfigSnapshot(const ValueMap & valueMap, int64_t generation);
+    void serializeV1(vespalib::slime::Cursor & root) const;
+    void serializeKeyV1(vespalib::slime::Cursor & root, const ConfigKey & key) const;
+    void serializeValueV1(vespalib::slime::Cursor & root, const Value & value) const;
+
+    void deserializeV1(vespalib::slime::Inspector & root);
+    ConfigKey deserializeKeyV1(vespalib::slime::Inspector & inspector) const;
+    Value deserializeValueV1(vespalib::slime::Inspector & inspector) const;
+
+    void serializeV2(vespalib::slime::Cursor & root) const;
+    void serializeValueV2(vespalib::slime::Cursor & root, const Value & value) const;
+
+    void deserializeV2(vespalib::slime::Inspector & root);
+    Value deserializeValueV2(vespalib::slime::Inspector & inspector) const;
+
+    ValueMap _valueMap;
+    int64_t _generation;
+};
+
+} // namespace config
+
+#include "configsnapshot.hpp"
+
diff --git a/config/src/vespa/config/retriever/configsnapshot.hpp b/config/src/vespa/config/retriever/configsnapshot.hpp
new file mode 100644
index 00000000000..b8e14fbceca
--- /dev/null
+++ b/config/src/vespa/config/retriever/configsnapshot.hpp
@@ -0,0 +1,37 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+namespace config {
+
+template <typename ConfigType>
+std::unique_ptr<ConfigType>
+ConfigSnapshot::getConfig(const vespalib::string & configId) const
+{
+    ConfigKey key(ConfigKey::create<ConfigType>(configId));
+    ValueMap::const_iterator it(_valueMap.find(key));
+    if (it == _valueMap.end()) {
+        throw IllegalConfigKeyException("Unable to find config for key " + key.toString());
+    }
+    return it->second.second.newInstance<ConfigType>();
+}
+
+template <typename ConfigType>
+bool
+ConfigSnapshot::isChanged(const vespalib::string & configId, int64_t currentGeneration) const
+{
+    ConfigKey key(ConfigKey::create<ConfigType>(configId));
+    ValueMap::const_iterator it(_valueMap.find(key));
+    if (it == _valueMap.end()) {
+        throw IllegalConfigKeyException("Unable to find config for key " + key.toString());
+    }
+    return currentGeneration < it->second.first;
+}
+
+template <typename ConfigType>
+bool
+ConfigSnapshot::hasConfig(const vespalib::string & configId) const
+{
+    ConfigKey key(ConfigKey::create<ConfigType>(configId));
+    return (_valueMap.find(key) != _valueMap.end());
+}
+
+}
diff --git a/config/src/vespa/config/retriever/fixedconfigsubscriber.cpp b/config/src/vespa/config/retriever/fixedconfigsubscriber.cpp
new file mode 100644
index 00000000000..7fb1ec9b337
--- /dev/null
+++ b/config/src/vespa/config/retriever/fixedconfigsubscriber.cpp
@@ -0,0 +1,40 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include "fixedconfigsubscriber.h"
+
+namespace config {
+FixedConfigSubscriber::FixedConfigSubscriber(const ConfigKeySet & keySet,
+                                             const IConfigContext::SP & context,
+                                             int64_t subscribeTimeout)
+    : _set(context),
+      _subscriptionList()
+{
+    for (ConfigKeySet::const_iterator it(keySet.begin()), mt(keySet.end()); it != mt; it++) {
+        _subscriptionList.push_back(_set.subscribe(*it, subscribeTimeout));
+    }
+}
+
+bool
+FixedConfigSubscriber::nextGeneration(int timeoutInMillis)
+{
+    return _set.acquireSnapshot(timeoutInMillis, true);
+}
+
+void
+FixedConfigSubscriber::close()
+{
+    _set.close();
+}
+
+int64_t
+FixedConfigSubscriber::getGeneration() const
+{
+    return _set.getGeneration();
+}
+
+ConfigSnapshot
+FixedConfigSubscriber::getConfigSnapshot() const
+{
+    return ConfigSnapshot(_subscriptionList, _set.getGeneration());
+}
+
+}
diff --git a/config/src/vespa/config/retriever/fixedconfigsubscriber.h b/config/src/vespa/config/retriever/fixedconfigsubscriber.h
new file mode 100644
index 00000000000..da570f5cf77
--- /dev/null
+++ b/config/src/vespa/config/retriever/fixedconfigsubscriber.h
@@ -0,0 +1,28 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/subscription/configsubscriptionset.h>
+#include "configkeyset.h"
+#include "configsnapshot.h"
+
+namespace config {
+
+/**
+ * The FixedConfigSubscriber takes an entires set of keys and subscribes to
+ * all of them. Once this is done, it cannot be resubscribed.
+ */
+class FixedConfigSubscriber
+{
+public:
+    FixedConfigSubscriber(const ConfigKeySet & keySet, const IConfigContext::SP & context, int64_t subscribeTimeout);
+    bool nextGeneration(int timeoutInMillis);
+    void close();
+    int64_t getGeneration() const;
+    ConfigSnapshot getConfigSnapshot() const;
+private:
+    ConfigSubscriptionSet _set;
+    std::vector<ConfigSubscription::SP> _subscriptionList;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/retriever/genericconfigsubscriber.cpp b/config/src/vespa/config/retriever/genericconfigsubscriber.cpp
new file mode 100644
index 00000000000..c2a7e05d538
--- /dev/null
+++ b/config/src/vespa/config/retriever/genericconfigsubscriber.cpp
@@ -0,0 +1,34 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include "genericconfigsubscriber.h"
+
+namespace config {
+
+GenericConfigSubscriber::GenericConfigSubscriber(const IConfigContext::SP & context)
+    : _set(context)
+{ }
+
+bool
+GenericConfigSubscriber::nextGeneration(int timeoutInMillis)
+{
+    return _set.acquireSnapshot(timeoutInMillis, true);
+}
+
+ConfigSubscription::SP
+GenericConfigSubscriber::subscribe(const ConfigKey & key, int timeoutInMillis)
+{
+    return _set.subscribe(key, timeoutInMillis);
+}
+
+void
+GenericConfigSubscriber::close()
+{
+    _set.close();
+}
+
+int64_t
+GenericConfigSubscriber::getGeneration() const
+{
+    return _set.getGeneration();
+}
+
+}
diff --git a/config/src/vespa/config/retriever/genericconfigsubscriber.h b/config/src/vespa/config/retriever/genericconfigsubscriber.h
new file mode 100644
index 00000000000..087e50a70e8
--- /dev/null
+++ b/config/src/vespa/config/retriever/genericconfigsubscriber.h
@@ -0,0 +1,26 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/subscription/configsubscriptionset.h>
+
+namespace config {
+
+/**
+ * The GenericConfigSubscriber is a generic form of a config subscriber, which
+ * does not require any type to be known. It also only supports generation
+ * changes.
+ */
+class GenericConfigSubscriber
+{
+public:
+    GenericConfigSubscriber(const IConfigContext::SP & context);
+    bool nextGeneration(int timeoutInMillis);
+    ConfigSubscription::SP subscribe(const ConfigKey & key, int timeoutInMillis);
+    void close();
+    int64_t getGeneration() const;
+private:
+    ConfigSubscriptionSet _set;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/retriever/simpleconfigretriever.cpp b/config/src/vespa/config/retriever/simpleconfigretriever.cpp
new file mode 100644
index 00000000000..011a9f6a519
--- /dev/null
+++ b/config/src/vespa/config/retriever/simpleconfigretriever.cpp
@@ -0,0 +1,37 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include "simpleconfigretriever.h"
+
+namespace config {
+SimpleConfigRetriever::SimpleConfigRetriever(const ConfigKeySet & keySet,
+                                             const IConfigContext::SP & context,
+                                             uint64_t subscribeTimeout)
+    : _set(context),
+      _subscriptionList()
+{
+    for (ConfigKeySet::const_iterator it(keySet.begin()), mt(keySet.end()); it != mt; it++) {
+        _subscriptionList.push_back(_set.subscribe(*it, subscribeTimeout));
+    }
+}
+
+ConfigSnapshot
+SimpleConfigRetriever::getConfigs(uint64_t timeoutInMillis)
+{
+    if (_set.acquireSnapshot(timeoutInMillis, true)) {
+        return ConfigSnapshot(_subscriptionList, _set.getGeneration());
+    }
+    return ConfigSnapshot();
+}
+
+void
+SimpleConfigRetriever::close()
+{
+    _set.close();
+}
+
+bool
+SimpleConfigRetriever::isClosed() const
+{
+    return _set.isClosed();
+}
+
+}
diff --git a/config/src/vespa/config/retriever/simpleconfigretriever.h b/config/src/vespa/config/retriever/simpleconfigretriever.h
new file mode 100644
index 00000000000..fc3f14bbeaa
--- /dev/null
+++ b/config/src/vespa/config/retriever/simpleconfigretriever.h
@@ -0,0 +1,41 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/subscription/configsubscriptionset.h>
+#include <vespa/config/common/timingvalues.h>
+#include "configkeyset.h"
+#include "configsnapshot.h"
+
+namespace config {
+
+/**
+ * The SimpleConfigRetriever takes an entires set of keys and subscribes to
+ * all of them. Once this is done, it cannot be resubscribed. You can poll this
+ * for new snapshots.
+ */
+class SimpleConfigRetriever
+{
+public:
+    typedef std::unique_ptr<SimpleConfigRetriever> UP;
+
+    SimpleConfigRetriever(const ConfigKeySet & keySet,
+                          const IConfigContext::SP & context,
+                          uint64_t subscribeTimeout = DEFAULT_SUBSCRIBE_TIMEOUT);
+
+    /**
+     * Attempt retrieving a snapshot of configs.
+     * @param timeoutInMillis The amount of time to wait for a new snapshot.
+     * @return A new snapshot. The snapshot is empty if timeout was reached or
+     *         if the retriever was closed.
+     */
+    ConfigSnapshot getConfigs(uint64_t timeoutInMillis = DEFAULT_GETCONFIGS_TIMEOUT);
+    void close();
+    bool isClosed() const;
+
+private:
+    ConfigSubscriptionSet _set;
+    std::vector<ConfigSubscription::SP> _subscriptionList;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/retriever/simpleconfigurer.cpp b/config/src/vespa/config/retriever/simpleconfigurer.cpp
new file mode 100644
index 00000000000..1b0e9cf9efe
--- /dev/null
+++ b/config/src/vespa/config/retriever/simpleconfigurer.cpp
@@ -0,0 +1,63 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/log/log.h>
+LOG_SETUP(".config.retriever.simpleconfigurer");
+#include "simpleconfigurer.h"
+
+namespace config {
+
+SimpleConfigurer::SimpleConfigurer(SimpleConfigRetriever::UP retriever, SimpleConfigurable * const configurable)
+    : _retriever(std::move(retriever)),
+      _configurable(configurable),
+      _thread(*this),
+      _started(false)
+{
+    assert(_retriever.get() != NULL);
+}
+
+void
+SimpleConfigurer::start()
+{
+    if (!_retriever->isClosed()) {
+        LOG(debug, "Polling for config");
+        runConfigure();
+        _thread.start();
+        _started = true;
+    }
+}
+
+SimpleConfigurer::~SimpleConfigurer()
+{
+    close();
+}
+
+void
+SimpleConfigurer::close()
+{
+    _retriever->close();
+    if (_started)
+        _thread.join();
+}
+
+void
+SimpleConfigurer::runConfigure()
+{
+    ConfigSnapshot snapshot(_retriever->getConfigs());
+    if (!snapshot.empty()) {
+        _configurable->configure(snapshot);
+    }
+}
+
+void
+SimpleConfigurer::run()
+{
+    while (!_retriever->isClosed()) {
+        try {
+            runConfigure();
+        } catch (const std::exception & e) {
+            LOG(fatal, "Fatal error while configuring: %s", e.what());
+        }
+    }
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/retriever/simpleconfigurer.h b/config/src/vespa/config/retriever/simpleconfigurer.h
new file mode 100644
index 00000000000..69d4eea545d
--- /dev/null
+++ b/config/src/vespa/config/retriever/simpleconfigurer.h
@@ -0,0 +1,54 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include "simpleconfigretriever.h"
+#include "configsnapshot.h"
+
+#include <vespa/vespalib/util/thread.h>
+#include <vespa/vespalib/util/runnable.h>
+
+#include <atomic>
+
+namespace config {
+
+class SimpleConfigurable
+{
+public:
+    virtual ~SimpleConfigurable() { }
+    virtual void configure(const ConfigSnapshot & snapshot) = 0;
+};
+
+/**
+ * A SimpleConfigurer runs in its own thread, uses a SimpleConfigRetriever to retrieve configs, and
+ * performs a callback whenever a newsnapshot is ready.
+ */
+class SimpleConfigurer : public vespalib::Runnable
+{
+public:
+    SimpleConfigurer(SimpleConfigRetriever::UP retriever, SimpleConfigurable * const configurable);
+    ~SimpleConfigurer();
+
+    /**
+     * Start the configurer thread. configure() is guaranteed to be called
+     * before this method returns.
+     */
+    void start();
+
+    /**
+     * Close the configurer. This will close the retriever as well!
+     */
+    void close();
+
+    void run();
+
+private:
+    void runConfigure();
+
+    SimpleConfigRetriever::UP _retriever;
+    SimpleConfigurable * const _configurable;
+    vespalib::Thread _thread;
+    std::atomic<bool> _started;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/set/.gitignore b/config/src/vespa/config/set/.gitignore
new file mode 100644
index 00000000000..7e7c0fe7fae
--- /dev/null
+++ b/config/src/vespa/config/set/.gitignore
@@ -0,0 +1,2 @@
+/.depend
+/Makefile
diff --git a/config/src/vespa/config/set/CMakeLists.txt b/config/src/vespa/config/set/CMakeLists.txt
new file mode 100644
index 00000000000..8f94598e577
--- /dev/null
+++ b/config/src/vespa/config/set/CMakeLists.txt
@@ -0,0 +1,8 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_library(config_set OBJECT
+    SOURCES
+    configsetsource.cpp
+    configsetsourcefactory.cpp
+    configinstancesourcefactory.cpp
+    DEPENDS
+)
diff --git a/config/src/vespa/config/set/configinstancesourcefactory.cpp b/config/src/vespa/config/set/configinstancesourcefactory.cpp
new file mode 100644
index 00000000000..fcf1b0f213b
--- /dev/null
+++ b/config/src/vespa/config/set/configinstancesourcefactory.cpp
@@ -0,0 +1,49 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include "configinstancesourcefactory.h"
+#include <vespa/config/common/source.h>
+#include <vespa/config/common/misc.h>
+
+namespace {
+
+class ConfigInstanceSource : public config::Source {
+public:
+    ConfigInstanceSource(const config::IConfigHolder::SP & holder, const vespalib::asciistream & buffer)
+        : _holder(holder),
+          _buffer(buffer),
+          _generation(-1)
+    { }
+    virtual void close() { }
+    virtual void getConfig() {
+        std::vector<vespalib::string> lines(_buffer.getlines());
+        std::string currentMd5(config::calculateContentMd5(lines));
+        _holder->handle(config::ConfigUpdate::UP(new config::ConfigUpdate(config::ConfigValue(lines, currentMd5), true, _generation)));
+
+    }
+    virtual void reload(int64_t generation) { _generation = generation; }
+private:
+    config::IConfigHolder::SP _holder;
+    vespalib::asciistream _buffer;
+    int64_t _generation;
+};
+
+}
+
+namespace config {
+
+ConfigInstanceSourceFactory::ConfigInstanceSourceFactory(const ConfigKey & key, const vespalib::asciistream & buffer)
+    : _key(key),
+      _buffer(buffer)
+{
+}
+
+Source::UP
+ConfigInstanceSourceFactory::createSource(const IConfigHolder::SP & holder, const ConfigKey & key) const
+{
+    (void) key;
+    // TODO: Check key against _key
+    return Source::UP(new ConfigInstanceSource(holder, _buffer));
+}
+
+} // namespace config
+
diff --git a/config/src/vespa/config/set/configinstancesourcefactory.h b/config/src/vespa/config/set/configinstancesourcefactory.h
new file mode 100644
index 00000000000..8b1a4c68cbd
--- /dev/null
+++ b/config/src/vespa/config/set/configinstancesourcefactory.h
@@ -0,0 +1,32 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/sourcefactory.h>
+#include "configsetsource.h"
+#include <vespa/vespalib/stllike/asciistream.h>
+
+namespace config {
+
+class Source;
+class IConfigHolder;
+class ConfigKey;
+
+/**
+ * Factory creating config payload from a single config instance
+ */
+class ConfigInstanceSourceFactory : public SourceFactory
+{
+public:
+    ConfigInstanceSourceFactory(const ConfigKey & key, const vespalib::asciistream & buffer);
+
+    /**
+     * Create source handling config described by key.
+     */
+    Source::UP createSource(const IConfigHolder::SP & holder, const ConfigKey & key) const;
+private:
+    const ConfigKey _key;
+    vespalib::asciistream _buffer;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/set/configsetsource.cpp b/config/src/vespa/config/set/configsetsource.cpp
new file mode 100644
index 00000000000..d98b28b8b6a
--- /dev/null
+++ b/config/src/vespa/config/set/configsetsource.cpp
@@ -0,0 +1,70 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.set.configsetsource");
+#include "configsetsource.h"
+#include <vespa/config/print/asciiconfigwriter.h>
+#include <vespa/config/common/misc.h>
+#include <vespa/vespalib/stllike/asciistream.h>
+
+namespace config {
+
+ConfigSetSource::ConfigSetSource(const IConfigHolder::SP & holder, const ConfigKey & key, const BuilderMapSP & builderMap)
+    : _holder(holder),
+      _key(key),
+      _generation(1),
+      _builderMap(builderMap)
+{
+    if (!validRequest(key))
+        throw ConfigRuntimeException("Invalid subscribe for key " + key.toString() + ", not builder found");
+}
+
+void
+ConfigSetSource::getConfig()
+{
+    BuilderMap::const_iterator it(_builderMap->find(_key));
+    ConfigInstance * instance = it->second;
+    vespalib::asciistream ss;
+    AsciiConfigWriter writer(ss);
+    writer.write(*instance);
+    std::vector<vespalib::string> lines(ss.getlines());
+    std::string currentMd5(calculateContentMd5(lines));
+
+    if (isGenerationNewer(_generation, _lastState.generation) && currentMd5.compare(_lastState.md5) != 0) {
+        LOG(debug, "New generation, updating");
+        _holder->handle(ConfigUpdate::UP(new ConfigUpdate(ConfigValue(lines, currentMd5), true, _generation)));
+        _lastState.md5 = currentMd5;
+        _lastState.generation = _generation;
+    } else {
+        LOG(debug, "Sending timestamp update");
+        _holder->handle(ConfigUpdate::UP(new ConfigUpdate(ConfigValue(lines, currentMd5), false, _generation)));
+        _lastState.generation = _generation;
+    }
+}
+
+void
+ConfigSetSource::reload(int64_t generation)
+{
+    LOG(debug, "Running update with generation(%" PRId64 ")", generation);
+    _generation = generation;
+}
+
+void
+ConfigSetSource::close()
+{
+}
+
+bool
+ConfigSetSource::validRequest(const ConfigKey & key)
+{
+    if (_builderMap->find(key) == _builderMap->end())
+        return false;
+    BuilderMap::const_iterator it(_builderMap->find(key));
+    ConfigInstance * instance = it->second;
+    return (key.getDefName().compare(instance->defName()) == 0 &&
+            key.getDefNamespace().compare(instance->defNamespace()) == 0);
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/set/configsetsource.h b/config/src/vespa/config/set/configsetsource.h
new file mode 100644
index 00000000000..78666ddb533
--- /dev/null
+++ b/config/src/vespa/config/set/configsetsource.h
@@ -0,0 +1,38 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/source.h>
+#include <vespa/config/common/configkey.h>
+#include <vespa/config/common/iconfigholder.h>
+#include <vespa/config/common/configstate.h>
+#include <map>
+
+namespace config {
+
+class ConfigInstance;
+
+/**
+ * Class for sending and receiving config request from a raw string.
+ */
+class ConfigSetSource : public Source {
+public:
+    typedef std::map<ConfigKey, ConfigInstance *> BuilderMap;
+    typedef std::shared_ptr<BuilderMap> BuilderMapSP;
+    ConfigSetSource(const IConfigHolder::SP & holder, const ConfigKey & key, const BuilderMapSP & builderMap);
+
+    void getConfig();
+    void reload(int64_t generation);
+    void close();
+private:
+    IConfigHolder::SP _holder;
+    const ConfigKey _key;
+    int64_t _generation;
+    BuilderMapSP _builderMap;
+    int64_t _lastGeneration;
+    ConfigState _lastState;
+
+    bool validRequest(const ConfigKey & key);
+};
+
+}
+
diff --git a/config/src/vespa/config/set/configsetsourcefactory.cpp b/config/src/vespa/config/set/configsetsourcefactory.cpp
new file mode 100644
index 00000000000..778ae9ee3cd
--- /dev/null
+++ b/config/src/vespa/config/set/configsetsourcefactory.cpp
@@ -0,0 +1,18 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include "configsetsourcefactory.h"
+
+namespace config {
+
+ConfigSetSourceFactory::ConfigSetSourceFactory(const BuilderMapSP & builderMap)
+    : _builderMap(builderMap)
+{
+}
+
+Source::UP
+ConfigSetSourceFactory::createSource(const IConfigHolder::SP & holder, const ConfigKey & key) const
+{
+    return Source::UP(new ConfigSetSource(holder, key, _builderMap));
+}
+
+} // namespace config
+
diff --git a/config/src/vespa/config/set/configsetsourcefactory.h b/config/src/vespa/config/set/configsetsourcefactory.h
new file mode 100644
index 00000000000..e3bac385e07
--- /dev/null
+++ b/config/src/vespa/config/set/configsetsourcefactory.h
@@ -0,0 +1,32 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/sourcefactory.h>
+#include "configsetsource.h"
+
+namespace config {
+
+class Source;
+class IConfigHolder;
+class ConfigKey;
+
+/**
+ * Factory creating config payload from config instances.
+ */
+class ConfigSetSourceFactory : public SourceFactory
+{
+public:
+    typedef ConfigSetSource::BuilderMap BuilderMap;
+    typedef ConfigSetSource::BuilderMapSP BuilderMapSP;
+    ConfigSetSourceFactory(const BuilderMapSP & builderMap);
+
+    /**
+     * Create source handling config described by key.
+     */
+    Source::UP createSource(const IConfigHolder::SP & holder, const ConfigKey & key) const;
+private:
+    BuilderMapSP _builderMap;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/subscription/.gitignore b/config/src/vespa/config/subscription/.gitignore
new file mode 100644
index 00000000000..7e7c0fe7fae
--- /dev/null
+++ b/config/src/vespa/config/subscription/.gitignore
@@ -0,0 +1,2 @@
+/.depend
+/Makefile
diff --git a/config/src/vespa/config/subscription/CMakeLists.txt b/config/src/vespa/config/subscription/CMakeLists.txt
new file mode 100644
index 00000000000..cce728c878a
--- /dev/null
+++ b/config/src/vespa/config/subscription/CMakeLists.txt
@@ -0,0 +1,10 @@
+# Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+vespa_add_library(config_subscription OBJECT
+    SOURCES
+    sourcespec.cpp
+    configsubscription.cpp
+    configsubscriber.cpp
+    configsubscriptionset.cpp
+    configuri.cpp
+    DEPENDS
+)
diff --git a/config/src/vespa/config/subscription/confighandle.h b/config/src/vespa/config/subscription/confighandle.h
new file mode 100644
index 00000000000..fddb1f5ccb6
--- /dev/null
+++ b/config/src/vespa/config/subscription/confighandle.h
@@ -0,0 +1,47 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <memory>
+#include <vespa/config/subscription/configsubscription.h>
+
+namespace config {
+
+/**
+ * A ConfigHandle is a subscription handle that is capable of looking up config
+ * objects of a generic type.
+ */
+template <typename ConfigType>
+class ConfigHandle
+{
+public:
+    typedef std::unique_ptr<ConfigHandle <ConfigType> > UP;
+
+    ConfigHandle(const ConfigSubscription::SP & subscription);
+
+    /**
+     * Return the currently available config known to the ConfigHandle. Throws
+     * a ConfigRuntimeException if the ConfigSubscriber has not yet been polled
+     * for config, and InvalidConfigException, if there are errors with the
+     * config payload.
+     *
+     * @return current config.
+     * @throws InvalidConfigException if unable instantiate the given type or
+     *         parse config.
+     */
+    std::unique_ptr<ConfigType> getConfig() const;
+
+    /**
+     * Returns whether or not this handles config has changed since the last
+     * call to ConfigSubscriber.nextConfig() was made.
+     *
+     * @return true if changed, false if not.
+     */
+    bool isChanged() const;
+private:
+    ConfigSubscription::SP _subscription;
+};
+
+} // namespace config
+
+#include "confighandle.hpp"
+
diff --git a/config/src/vespa/config/subscription/confighandle.hpp b/config/src/vespa/config/subscription/confighandle.hpp
new file mode 100644
index 00000000000..86afc8d4f43
--- /dev/null
+++ b/config/src/vespa/config/subscription/confighandle.hpp
@@ -0,0 +1,26 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+
+namespace config {
+
+template <typename ConfigType>
+ConfigHandle<ConfigType>::ConfigHandle(const ConfigSubscription::SP & subscription)
+    : _subscription(subscription)
+{
+}
+
+template <typename ConfigType>
+std::unique_ptr<ConfigType>
+ConfigHandle<ConfigType>::getConfig() const
+{
+    return _subscription->getConfig().newInstance<ConfigType>();
+}
+
+template <typename ConfigType>
+bool
+ConfigHandle<ConfigType>::isChanged() const
+{
+    return _subscription->isChanged();
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/subscription/configprovider.h b/config/src/vespa/config/subscription/configprovider.h
new file mode 100644
index 00000000000..56c5f685eae
--- /dev/null
+++ b/config/src/vespa/config/subscription/configprovider.h
@@ -0,0 +1,30 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <vespa/config/common/configvalue.h>
+
+namespace config {
+
+
+class ConfigProvider
+{
+public:
+    virtual ~ConfigProvider() { }
+
+    /**
+     * Fetches the appropriate ConfigValue.
+     *
+     * @return the current ConfigValue.
+     */
+    virtual ConfigValue getConfig() const = 0;
+
+    /**
+     * Checks whether or not the config has changed.
+     *
+     * @return true if changed, false if not.
+     */
+    virtual bool isChanged() const = 0;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/subscription/configsubscriber.cpp b/config/src/vespa/config/subscription/configsubscriber.cpp
new file mode 100644
index 00000000000..092c460ece1
--- /dev/null
+++ b/config/src/vespa/config/subscription/configsubscriber.cpp
@@ -0,0 +1,52 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.subscription.configsubscriber");
+
+#include "configsubscriber.h"
+#include <vespa/config/common/exceptions.h>
+
+namespace config {
+
+
+ConfigSubscriber::ConfigSubscriber(const IConfigContext::SP & context)
+    : _set(context)
+
+{ }
+
+ConfigSubscriber::ConfigSubscriber(const SourceSpec & spec)
+    : _set(IConfigContext::SP(new ConfigContext(spec)))
+{ }
+
+bool
+ConfigSubscriber::nextConfig(uint64_t timeoutInMillis)
+{
+    return _set.acquireSnapshot(timeoutInMillis, false);
+}
+
+bool
+ConfigSubscriber::nextGeneration(uint64_t timeoutInMillis)
+{
+    return _set.acquireSnapshot(timeoutInMillis, true);
+}
+
+void
+ConfigSubscriber::close()
+{
+    _set.close();
+}
+
+bool
+ConfigSubscriber::isClosed() const
+{
+    return _set.isClosed();
+}
+
+int64_t
+ConfigSubscriber::getGeneration() const
+{
+    return _set.getGeneration();
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/subscription/configsubscriber.h b/config/src/vespa/config/subscription/configsubscriber.h
new file mode 100644
index 00000000000..194aad75276
--- /dev/null
+++ b/config/src/vespa/config/subscription/configsubscriber.h
@@ -0,0 +1,112 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+#include <memory>
+#include <map>
+#include <vespa/config/common/iconfigholder.h>
+#include <vespa/config/common/configcontext.h>
+#include <vespa/config/common/timingvalues.h>
+#include "confighandle.h"
+#include "subscriptionid.h"
+#include "configsubscription.h"
+#include "configsubscriptionset.h"
+#include "configprovider.h"
+#include "sourcespec.h"
+
+namespace config {
+
+/**
+ * A subscriber is a class capable of subscribing to one or more configs. The
+ * class should be used as follows:
+ * - subscribe for all configs you need.
+ * - run nextConfig or nextGeneration to fetch the next generation of configs.
+ *
+ * Once nextConfig/nextGeneration is called, the state of a ConfigSubscriber is
+ * FROZEN, which means that in order to change the set of subscriptions, you
+ * have to recreate the ConfigSubscriber.
+ *
+ * Note that this class is NOT thread safe and that you should design your
+ * application so that you only need to use it from one thread.
+ */
+class ConfigSubscriber
+{
+public:
+    typedef std::unique_ptr<ConfigSubscriber> UP;
+
+    /**
+     * Constructs a new ConfigSubscriber object which can be used to subscribe
+     * for 1 or more configs.
+     *
+     * @param spec The source spec from which to get config.
+     */
+    ConfigSubscriber(const SourceSpec & spec = ServerSpec());
+
+    /**
+     * Constructs a new ConfigSubscriber object which can be used to subscribe
+     * for 1 or more configs. The provided context is used to share resources
+     * betweeen multiple config subscribers.
+     *
+     * @param context A ConfigContext shared between all subscribers.
+     */
+    ConfigSubscriber(const IConfigContext::SP & context);
+
+    /**
+     * Checks if one or more of the configs in the set is updated or not.
+     *
+     * @param timeoutInMillis The timeout in milliseconds.
+     * @return true if new configs are available, false if timeout was reached
+     *              or subscriber has been closed.
+     */
+    bool nextConfig(uint64_t timeoutInMillis = DEFAULT_NEXTCONFIG_TIMEOUT);
+
+    /**
+     * Checks if the generation of this config set is updated.
+     *
+     * @param timeoutInMillis The timeout in milliseconds.
+     * @return true if a new generation are available, false if timeout was reached
+     *              or subscriber has been closed.
+     */
+    bool nextGeneration(uint64_t timeoutInMillis = DEFAULT_NEXTCONFIG_TIMEOUT);
+
+    /**
+     * Subscribe to a config fetched from the default source specification.
+     *
+     * @param configId        The configId to get config for.
+     * @param timeoutInMillis An optional timeout on the subscribe call, in
+     *                        milliseconds.
+     * @return                A subscription handle which can be used to
+     *                        retrieve config.
+     * @throws ConfigTimeoutException if subscription timed out.
+     * @throws ConfigRuntimeException if subscriber has been closed.
+     */
+    template <typename ConfigType>
+    std::unique_ptr<ConfigHandle<ConfigType> >
+    subscribe(const std::string & configId, uint64_t timeoutInMillis = DEFAULT_SUBSCRIBE_TIMEOUT);
+
+    /**
+     * Return the current generation number for configs.
+     *
+     * @return generation number
+     */
+    int64_t getGeneration() const;
+
+    /**
+     * Closes the set, which will interrupt nextConfig() or nextGeneration(), and unsubscribe all
+     * configs currently subscribed for.
+     */
+    void close();
+
+    /**
+     * Check if this retriever is closed.
+     *
+     * @return true if closed, false if not.
+     */
+    bool isClosed() const;
+
+private:
+    ConfigSubscriptionSet _set;                   // The set of subscriptions for this set.
+};
+
+} // namespace config
+
+#include "configsubscriber.hpp"
+
diff --git a/config/src/vespa/config/subscription/configsubscriber.hpp b/config/src/vespa/config/subscription/configsubscriber.hpp
new file mode 100644
index 00000000000..eed67897c9a
--- /dev/null
+++ b/config/src/vespa/config/subscription/configsubscriber.hpp
@@ -0,0 +1,13 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+namespace config {
+
+template <typename ConfigType>
+std::unique_ptr<ConfigHandle<ConfigType> >
+ConfigSubscriber::subscribe(const std::string & configId, uint64_t timeoutInMillis)
+{
+    const ConfigKey key(ConfigKey::create<ConfigType>(configId));
+    return std::unique_ptr<ConfigHandle<ConfigType> >(new ConfigHandle<ConfigType>(_set.subscribe(key, timeoutInMillis)));
+}
+
+}
diff --git a/config/src/vespa/config/subscription/configsubscription.cpp b/config/src/vespa/config/subscription/configsubscription.cpp
new file mode 100644
index 00000000000..c8d4f66091c
--- /dev/null
+++ b/config/src/vespa/config/subscription/configsubscription.cpp
@@ -0,0 +1,117 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/fastos/fastos.h>
+#include <vespa/config/common/exceptions.h>
+#include <vespa/config/common/misc.h>
+#include "configsubscription.h"
+
+namespace config {
+
+ConfigSubscription::ConfigSubscription(const SubscriptionId & id, const ConfigKey & key, const IConfigHolder::SP & holder, Source::UP source)
+    : _id(id),
+      _key(key),
+      _source(std::move(source)),
+      _holder(holder),
+      _next(),
+      _current(),
+      _isChanged(false),
+      _lastGenerationChanged(-1),
+      _closed(false)
+{
+}
+
+ConfigSubscription::~ConfigSubscription()
+{
+    close();
+}
+
+
+bool
+ConfigSubscription::nextUpdate(int64_t generation, uint64_t timeoutInMillis)
+{
+    if (_closed || !_holder->poll())
+        return false;
+    _next.reset(_holder->provide().release());
+    if (isGenerationNewer(_next->getGeneration(), generation)) {
+        return true;
+    }
+    return (!_closed && _holder->wait(timeoutInMillis));
+}
+
+bool
+ConfigSubscription::hasChanged() const
+{
+    return (!_closed && (_next->hasChanged() || _current.get() == NULL));
+}
+
+int64_t
+ConfigSubscription::getGeneration() const
+{
+    return _next->getGeneration();
+}
+
+const ConfigKey &
+ConfigSubscription::getKey() const
+{
+    return _key;
+}
+
+void
+ConfigSubscription::close()
+{
+    if (!_closed) {
+        _closed = true;
+        _holder->interrupt();
+        _source->close();
+    }
+}
+
+void
+ConfigSubscription::reset()
+{
+    _isChanged = false;
+}
+
+bool
+ConfigSubscription::isChanged() const
+{
+    return _isChanged;
+}
+
+int64_t
+ConfigSubscription::getLastGenerationChanged() const
+{
+    return _lastGenerationChanged;
+}
+
+void
+ConfigSubscription::flip()
+{
+    bool change = hasChanged();
+    if (change) {
+        _current.reset(_next.release());
+        _lastGenerationChanged = _current->getGeneration();
+    } else {
+        _current.reset(new ConfigUpdate(_current->getValue(), false, _next->getGeneration()));
+    }
+    _isChanged = change;
+}
+
+ConfigValue
+ConfigSubscription::getConfig() const
+{
+    if (_closed)
+        throw ConfigRuntimeException("Subscription is closed, config no longer available");
+    if (_current.get() == NULL)
+        throw ConfigRuntimeException("No configuration available");
+    return _current->getValue();
+}
+
+void
+ConfigSubscription::reload(int64_t generation)
+{
+    _source->reload(generation);
+    _source->getConfig();
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/subscription/configsubscription.h b/config/src/vespa/config/subscription/configsubscription.h
new file mode 100644
index 00000000000..cfc33cdbb3e
--- /dev/null
+++ b/config/src/vespa/config/subscription/configsubscription.h
@@ -0,0 +1,73 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+#include <memory>
+#include <vespa/config/common/iconfigholder.h>
+#include <vespa/config/common/configkey.h>
+#include <vespa/config/common/source.h>
+#include "subscriptionid.h"
+
+#include <atomic>
+
+namespace config {
+
+/**
+ * A subscription can be polled for config updates, and handles interruption of
+ * the nextUpdate call.
+ */
+class ConfigSubscription
+{
+public:
+    typedef std::unique_ptr<ConfigSubscription> UP;
+    typedef std::shared_ptr<ConfigSubscription> SP;
+
+    ConfigSubscription(const SubscriptionId & id, const ConfigKey & key, const IConfigHolder::SP & holder, Source::UP source);
+    ~ConfigSubscription();
+
+    /**
+     * Fetches the appropriate ConfigValue.
+     *
+     * @return the current ConfigValue.
+     */
+    ConfigValue getConfig() const;
+
+    /**
+     * Checks whether or not the config has changed.
+     *
+     * @return true if changed, false if not.
+     */
+    bool isChanged() const;
+
+    /**
+     * Returns the last generation that actually changed the config.
+     */
+    int64_t getLastGenerationChanged() const;
+
+    /// Used by ConfigSubscriptionSet
+    SubscriptionId getSubscriptionId() const { return _id; }
+    const ConfigKey & getKey() const;
+    bool nextUpdate(int64_t generation, uint64_t timeoutInMillis);
+    int64_t getGeneration() const;
+    bool hasChanged() const;
+    void flip();
+    void reset();
+    void close();
+
+    // Used by ConfigManager
+    void reload(int64_t generation);
+
+private:
+    const SubscriptionId _id;
+    const ConfigKey _key;
+    Source::UP _source;
+    IConfigHolder::SP _holder;
+    ConfigUpdate::UP _next;
+    ConfigUpdate::UP _current;
+    bool _isChanged;
+    int64_t _lastGenerationChanged;
+    std::atomic<bool> _closed;
+};
+
+typedef std::vector<ConfigSubscription::SP> SubscriptionList;
+
+} // namespace config
+
diff --git a/config/src/vespa/config/subscription/configsubscriptionset.cpp b/config/src/vespa/config/subscription/configsubscriptionset.cpp
new file mode 100644
index 00000000000..b19812a3fc6
--- /dev/null
+++ b/config/src/vespa/config/subscription/configsubscriptionset.cpp
@@ -0,0 +1,136 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.subscription.configsubscriptionset");
+
+#include "configsubscriptionset.h"
+#include <vespa/config/common/exceptions.h>
+
+namespace config {
+
+ConfigSubscriptionSet::ConfigSubscriptionSet(const IConfigContext::SP & context)
+    : _context(context),
+      _mgr(context->getManagerInstance()),
+      _currentGeneration(-1),
+      _subscriptionList(),
+      _state(OPEN)
+{ }
+
+ConfigSubscriptionSet::~ConfigSubscriptionSet()
+{
+    close();
+}
+
+bool
+ConfigSubscriptionSet::acquireSnapshot(uint64_t timeoutInMillis, bool ignoreChange)
+{
+    if (_state == CLOSED) {
+        return false;
+    } else if (_state == OPEN)
+        _state = FROZEN;
+
+    FastOS_Time timer;
+    timer.SetNow();
+    int timeLeft = timeoutInMillis;
+    int64_t lastGeneration = _currentGeneration;
+    bool inSync = false;
+
+    for (SubscriptionList::iterator it(_subscriptionList.begin()), mt(_subscriptionList.end());
+         it != mt;
+         it++) {
+        (*it)->reset();
+    }
+
+    LOG(debug, "Going into nextConfig loop, time left is %d", timeLeft);
+    while (_state != CLOSED && timeLeft >= 0 && !inSync) {
+        size_t numChanged = 0;
+        size_t numGenerationChanged = 0;
+        bool generationsInSync = true;
+        int64_t generation = -1;
+
+        // Run nextUpdate on all subscribers to get them in sync.
+        for (SubscriptionList::iterator it(_subscriptionList.begin()), mt(_subscriptionList.end());
+             it != mt;
+             it++) {
+            ConfigSubscription::SP subscription = *it;
+
+            if (!subscription->nextUpdate(_currentGeneration, timeLeft))
+                break;
+
+            const ConfigKey & key(subscription->getKey());
+            if (subscription->hasChanged()) {
+                LOG(spam, "Config subscription has changed id(%s), defname(%s)", key.getConfigId().c_str(), key.getDefName().c_str());
+                numChanged++;
+            } else {
+                LOG(spam, "Config subscription did not change, id(%s), defname(%s)", key.getConfigId().c_str(), key.getDefName().c_str());
+            }
+            LOG(spam, "Previous generation is %" PRId64 ", updates is %" PRId64, generation, subscription->getGeneration());
+            if (isGenerationNewer(subscription->getGeneration(), _currentGeneration)) {
+                numGenerationChanged++;
+            }
+            if (generation < 0)
+                generation = subscription->getGeneration();
+            if (subscription->getGeneration() != generation)
+                generationsInSync = false;
+            // Adjust timeout
+            timeLeft = timeoutInMillis - static_cast<uint64_t>(timer.MilliSecsToNow());
+        }
+        inSync = generationsInSync && (_subscriptionList.size() == numGenerationChanged) && (ignoreChange || numChanged > 0);
+        lastGeneration = generation;
+        timeLeft = timeoutInMillis - static_cast<uint64_t>(timer.MilliSecsToNow());
+        if (!inSync && timeLeft > 0) {
+            FastOS_Thread::Sleep(10);
+        }
+    }
+
+    bool updated = inSync && isGenerationNewer(lastGeneration, _currentGeneration);
+    if (updated) {
+        LOG(spam, "Config was updated from %" PRId64 " to %" PRId64, _currentGeneration, lastGeneration);
+        _currentGeneration = lastGeneration;
+        _state = CONFIGURED;
+        for (SubscriptionList::iterator it(_subscriptionList.begin()), mt(_subscriptionList.end());
+             it != mt;
+             it++) {
+            (*it)->flip();
+        }
+    }
+    return updated;
+}
+
+void
+ConfigSubscriptionSet::close()
+{
+    _state = CLOSED;
+    for (SubscriptionList::iterator it(_subscriptionList.begin()), mt(_subscriptionList.end()); it != mt; it++) {
+        _mgr.unsubscribe(*it);
+        (*it)->close();
+    }
+}
+
+bool
+ConfigSubscriptionSet::isClosed() const
+{
+    return (_state == CLOSED);
+}
+
+ConfigSubscription::SP
+ConfigSubscriptionSet::subscribe(const ConfigKey & key, uint64_t timeoutInMillis)
+{
+    if (_state != OPEN) {
+        throw ConfigRuntimeException("Adding subscription after calling nextConfig() is not allowed");
+    }
+    LOG(debug, "Subscribing with config Id(%s), defName(%s)", key.getConfigId().c_str(), key.getDefName().c_str());
+
+    ConfigSubscription::SP s = _mgr.subscribe(key, timeoutInMillis);
+    _subscriptionList.push_back(s);
+    return s;
+}
+
+int64_t
+ConfigSubscriptionSet::getGeneration() const
+{
+    return _currentGeneration;
+}
+
+} // namespace config
diff --git a/config/src/vespa/config/subscription/configsubscriptionset.h b/config/src/vespa/config/subscription/configsubscriptionset.h
new file mode 100644
index 00000000000..3c425baf26c
--- /dev/null
+++ b/config/src/vespa/config/subscription/configsubscriptionset.h
@@ -0,0 +1,69 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+#include <memory>
+#include <map>
+#include <vespa/config/common/iconfigholder.h>
+#include <vespa/config/common/configcontext.h>
+#include "confighandle.h"
+#include "subscriptionid.h"
+#include "configsubscription.h"
+#include "configprovider.h"
+#include <vespa/vespalib/util/sync.h>
+#include <vespa/vespalib/util/priority_queue.h>
+
+namespace config {
+
+/**
+ * A ConfigSubscriptionSet is a set of configs that can be subscribed to.
+ */
+class ConfigSubscriptionSet
+{
+public:
+    /**
+     * Constructs a new ConfigSubscriptionSet object which can be used to subscribe for 1
+     * or more configs from a specific source.
+     *
+     * @param context A ConfigContext shared between all subscriptions.
+     */
+    ConfigSubscriptionSet(const IConfigContext::SP & context);
+
+    ~ConfigSubscriptionSet();
+
+    /**
+     * Return the current generation number for configs.
+     *
+     * @return generation number
+     */
+    int64_t getGeneration() const;
+
+    /**
+     * Closes the set, which will interrupt acquireSnapshot and unsubscribe all
+     * configs currently subscribed for.
+     */
+    void close();
+
+    /**
+     * Checks if this subscription set is closed.
+     */
+    bool isClosed() const;
+
+    // Helpers for doing the subscription
+    ConfigSubscription::SP subscribe(const ConfigKey & key, uint64_t timeoutInMillis);
+
+    // Tries to acquire a new snapshot of config within the timeout
+    bool acquireSnapshot(uint64_t timeoutInMillis, bool requireDifference);
+
+private:
+    // Describes the state of the subscriber.
+    enum SubscriberState { OPEN, FROZEN, CONFIGURED, CLOSED };
+
+    IConfigContext::SP    _context;               // Context to keep alive managers.
+    IConfigManager &      _mgr;                   // The config manager that we use.
+    int64_t               _currentGeneration;     // Holds the current config generation.
+    SubscriptionList      _subscriptionList;      // List of current subscriptions.
+
+    SubscriberState _state;              // Current state of this subscriber.
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/subscription/configuri.cpp b/config/src/vespa/config/subscription/configuri.cpp
new file mode 100644
index 00000000000..68f883b70b5
--- /dev/null
+++ b/config/src/vespa/config/subscription/configuri.cpp
@@ -0,0 +1,56 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include "configuri.h"
+#include <vespa/config/helper/legacy.h>
+#include <vespa/config/subscription/sourcespec.h>
+
+namespace {
+bool checkEmpty(const vespalib::string & configId) {
+    return configId.empty();
+}
+}
+namespace config {
+
+ConfigUri::ConfigUri(const vespalib::string &configId)
+    : _configId(legacyConfigId2ConfigId(configId)),
+      _context(new ConfigContext(*legacyConfigId2Spec(configId))),
+      _empty(checkEmpty(configId))
+{
+}
+
+ConfigUri::ConfigUri(const vespalib::string &configId, const IConfigContext::SP & context)
+    : _configId(configId),
+      _context(context),
+      _empty(false)
+{
+}
+
+ConfigUri
+ConfigUri::createWithNewId(const vespalib::string & configId) const
+{
+    return ConfigUri(configId, _context);
+}
+
+const vespalib::string & ConfigUri::getConfigId() const { return _configId; }
+const IConfigContext::SP & ConfigUri::getContext() const { return _context; }
+
+ConfigUri
+ConfigUri::createFromInstance(const ConfigInstance & instance)
+{
+    return ConfigUri("", IConfigContext::SP(new ConfigContext(ConfigInstanceSpec(instance))));
+}
+
+ConfigUri
+ConfigUri::createEmpty()
+{
+    ConfigUri uri("", IConfigContext::SP(new ConfigContext(RawSpec(""))));
+    uri._empty = true;
+    return uri;
+}
+
+ConfigUri ConfigUri::createFromSpec(const vespalib::string& configId, const SourceSpec& spec)
+{
+    return ConfigUri(configId, IConfigContext::SP(new ConfigContext(spec)));
+}
+
+
+} // namespace config
diff --git a/config/src/vespa/config/subscription/configuri.h b/config/src/vespa/config/subscription/configuri.h
new file mode 100644
index 00000000000..c88f092cf66
--- /dev/null
+++ b/config/src/vespa/config/subscription/configuri.h
@@ -0,0 +1,104 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+
+#include <string>
+#include <vespa/config/common/configcontext.h>
+
+namespace config {
+
+/**
+ * A ConfigUri is a single representation of a configId and its source. The
+ * purpose of this class is to make it more convenient to deal with config
+ * subscription for single-config components. The uri can be constructed from a
+ * config id, or a config id combined with a context, or by using the static
+ * factory methods to create an uri from a single instance.
+ */
+class ConfigUri {
+public:
+    /**
+     * Construct a config URI from a given config id.
+     * @param configId The config id.
+     */
+    ConfigUri(const char * configId) : ConfigUri(vespalib::string(configId)) {}
+
+    /**
+     * Construct a config URI from a given config id.
+     * @param configId The config id.
+     */
+    ConfigUri(const std::string &configId) : ConfigUri(vespalib::string(configId)) {}
+
+    /**
+     * Construct a config URI from a given config id.
+     * @param configId The config id.
+     */
+    ConfigUri(const vespalib::stringref &configId) : ConfigUri(vespalib::string(configId)) {}
+
+    /**
+     * Construct a config URI from a given config id.
+     * @param configId The config id.
+     */
+    ConfigUri(const vespalib::string &configId);
+
+    /**
+     * Construct a config URI from a config id and a context.
+     * @param configId The config id.
+     * @param context A context object that can be shared with multiple URIs.
+     */
+    ConfigUri(const vespalib::string &configId, const IConfigContext::SP & context);
+
+    /**
+     * Create a new config Uri with a different config id, but with the same
+     * context as this URI.
+     * @param configId The config id to give the new URI.
+     * @return A new config URI.
+     */
+    ConfigUri createWithNewId(const vespalib::string & configId) const;
+
+    /**
+     * Create a config uri from a config instance. The instance does not need
+     * to be kept alive.
+     * @param instance The config instance to use as source.
+     * @return A config uri.
+     */
+    static ConfigUri createFromInstance(const ConfigInstance & instance);
+
+    /**
+     * Create uri from a config id and a source spec.
+     *
+     * @param configId The config id to subscribe to.
+     * @param spec The source spec pointing to the config source.
+     */
+    static ConfigUri createFromSpec(const vespalib::string & configId,
+                                    const SourceSpec & spec);
+
+    /**
+     * Create a new empty config uri as initialization convenience.
+     */
+    static ConfigUri createEmpty();
+
+    /**
+     * Get this URIs config id. Used by subscriber.
+     * @return The config id of this uri.
+     */
+    const vespalib::string & getConfigId() const;
+
+    /**
+     * Get the context for this uri. Used by subscriber.
+     * @return The context.
+     */
+    const IConfigContext::SP & getContext() const;
+
+    /**
+     * Empty if the original id was empty or created with createEmpty
+     * @return true if empty.
+     */
+    bool empty() const { return _empty; }
+
+private:
+    vespalib::string _configId;
+    IConfigContext::SP _context;
+    bool _empty;
+};
+
+} // namespace config
+
diff --git a/config/src/vespa/config/subscription/sourcespec.cpp b/config/src/vespa/config/subscription/sourcespec.cpp
new file mode 100644
index 00000000000..0b5951ddec7
--- /dev/null
+++ b/config/src/vespa/config/subscription/sourcespec.cpp
@@ -0,0 +1,166 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#include <vespa/fastos/fastos.h>
+#include <vespa/log/log.h>
+LOG_SETUP(".config.subscription.sourcespec");
+#include "sourcespec.h"
+#include <vespa/config/common/exceptions.h>
+#include <vespa/config/raw/rawsourcefactory.h>
+#include <vespa/config/file/filesourcefactory.h>
+#include <vespa/config/frt/frtsourcefactory.h>
+#include <vespa/config/frt/frtconnectionpool.h>
+#include <vespa/config/frt/protocol.h>
+#include <vespa/config/frt/connectionfactory.h>
+#include <vespa/config/set/configsetsourcefactory.h>
+#include <vespa/config/set/configinstancesourcefactory.h>
+#include <vespa/vespalib/text/stringtokenizer.h>
+#include <vespa/config/print/asciiconfigwriter.h>
+#include <vespa/vespalib/stllike/asciistream.h>
+
+namespace config {
+
+RawSpec::RawSpec(const vespalib::string & config)
+    : _config(config)
+{
+}
+
+SourceFactory::UP
+RawSpec::createSourceFactory(const TimingValues & timingValues) const
+{
+    (void) timingValues;
+    return SourceFactory::UP(new RawSourceFactory(_config));
+}
+
+FileSpec::FileSpec(const vespalib::string & fileName)
+    : _fileName(fileName)
+{
+    verifyName(_fileName);
+}
+
+void
+FileSpec::verifyName(const vespalib::string & fileName)
+{
+    if (fileName.length() > 4) {
+        std::string ending(fileName.substr(fileName.length() - 4, 4));
+        if (ending.compare(".cfg") != 0)
+            throw InvalidConfigSourceException("File name '" + fileName + "' is invalid, must end with .cfg");
+    } else {
+        throw InvalidConfigSourceException("File name '" + fileName + "' is invalid");
+    }
+}
+
+SourceFactory::UP
+FileSpec::createSourceFactory(const TimingValues & timingValues) const
+{
+    (void) timingValues;
+    return SourceFactory::UP(new FileSourceFactory(*this));
+}
+
+DirSpec::DirSpec(const vespalib::string & dirName)
+    : _dirName(dirName)
+{
+}
+
+SourceFactory::UP
+DirSpec::createSourceFactory(const TimingValues & timingValues) const
+{
+    (void) timingValues;
+    return SourceFactory::UP(new DirSourceFactory(*this));
+}
+
+ServerSpec::ServerSpec()
+    : _hostList(),
+      _protocolVersion(protocol::readProtocolVersion()),
+      _traceLevel(protocol::readTraceLevel()),
+      _compressionType(protocol::readProtocolCompressionType())
+{
+    char* cfgSourcesPtr = getenv("VESPA_CONFIG_SOURCES");
+    if (cfgSourcesPtr != NULL) {
+        vespalib::string cfgSourcesStr(cfgSourcesPtr);
+        initialize(cfgSourcesStr);
+    } else {
+        initialize("localhost");
+    }
+}
+
+void
+ServerSpec::initialize(const vespalib::string & hostSpec)
+{
+    typedef vespalib::StringTokenizer tokenizer;
+    tokenizer tok(hostSpec, ",");
+    for (tokenizer::Iterator it = tok.begin(); it != tok.end(); it++) {
+        std::string srcHost = *it;
+        vespalib::asciistream spec;
+        if (srcHost.find("tcp/") == std::string::npos) {
+            spec << "tcp/";
+        }
+        spec << srcHost;
+        if (srcHost.find(":") == std::string::npos) {
+            spec << ":" << DEFAULT_PROXY_PORT;
+        }
+        _hostList.push_back(spec.str());
+    }
+}
+
+ServerSpec::ServerSpec(const HostSpecList & hostList)
+    : _hostList(hostList),
+      _protocolVersion(protocol::readProtocolVersion()),
+      _traceLevel(protocol::readTraceLevel()),
+      _compressionType(protocol::readProtocolCompressionType())
+{
+}
+
+ServerSpec::ServerSpec(const vespalib::string & hostSpec)
+    : _hostList(),
+      _protocolVersion(protocol::readProtocolVersion()),
+      _traceLevel(protocol::readTraceLevel()),
+      _compressionType(protocol::readProtocolCompressionType())
+{
+    initialize(hostSpec);
+}
+
+SourceFactory::UP
+ServerSpec::createSourceFactory(const TimingValues & timingValues) const
+{
+    const auto vespaVersion = VespaVersion::getCurrentVersion();
+    return SourceFactory::UP(new FRTSourceFactory(ConnectionFactory::UP(new FRTConnectionPool(*this, timingValues)), timingValues, _protocolVersion, _traceLevel, vespaVersion, _compressionType));
+}
+
+
+ConfigSet::ConfigSet()
+    : _builderMap(new BuilderMap())
+{
+}
+
+SourceFactory::UP
+ConfigSet::createSourceFactory(const TimingValues & timingValues) const
+{
+    (void) timingValues;
+    return SourceFactory::UP(new ConfigSetSourceFactory(_builderMap));
+}
+
+void
+ConfigSet::addBuilder(const vespalib::string & configId, ConfigInstance * builder)
+{
+    assert(builder != NULL);
+    BuilderMap & builderMap(*_builderMap);
+    const ConfigKey key(configId, builder->defName(), builder->defNamespace(), builder->defMd5());
+    builderMap[key] = builder;
+}
+
+ConfigInstanceSpec::ConfigInstanceSpec(const ConfigInstance& instance)
+    : _key("", instance.defName(), instance.defNamespace(), instance.defMd5()),
+      _buffer()
+{
+    AsciiConfigWriter writer(_buffer);
+    writer.write(instance);
+}
+
+SourceFactory::UP
+ConfigInstanceSpec::createSourceFactory(const TimingValues& timingValues) const
+{
+    (void) timingValues;
+    return SourceFactory::UP(new ConfigInstanceSourceFactory(_key, _buffer));
+}
+
+
+}
diff --git a/config/src/vespa/config/subscription/sourcespec.h b/config/src/vespa/config/subscription/sourcespec.h
new file mode 100644
index 00000000000..2378ee0bb06
--- /dev/null
+++ b/config/src/vespa/config/subscription/sourcespec.h
@@ -0,0 +1,251 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+
+#pragma once
+
+#include <vespa/vespalib/stllike/hash_fun.h>
+#include <vespa/vespalib/stllike/string.h>
+#include <vespa/config/common/sourcefactory.h>
+#include <vespa/config/common/timingvalues.h>
+#include <vespa/config/common/compressiontype.h>
+#include <vespa/config/set/configsetsourcefactory.h>
+#include <vespa/config/configgen/configinstance.h>
+#include <vespa/vespalib/stllike/asciistream.h>
+#include <map>
+
+namespace config {
+
+typedef vespalib::string SourceSpecKey;
+
+/**
+ * A source spec is a user provided specification of which sources to fetch
+ * config from.
+ */
+class SourceSpec
+{
+public:
+    typedef std::unique_ptr<SourceSpec> UP; /// Convenience typedef
+
+    /**
+     * Creates a source factory from which to create config sources for new
+     * subscriptions. The UpdateHandler should be
+     * provided to the source for it to post any update given any config
+     * request.
+     *
+     * @param handler A pointer to the update handler that will receive config
+     *                updates from the source.
+     * @param timingValues Timing values to be used for this source.
+     * @return An std::unique_ptr<Source> that can be used to ask for config.
+     */
+    virtual SourceFactory::UP createSourceFactory(const TimingValues & timingValues) const = 0;
+    virtual ~SourceSpec() { }
+};
+
+
+/**
+ * A RawSpec gives the ability to specify config as a raw config string.
+ */
+class RawSpec : public SourceSpec
+{
+public:
+    /**
+     * Constructs a new RawSpec that can be sent with a subscribe call.
+     *
+     * @param config The config represented as a raw string.
+     */
+    RawSpec(const vespalib::string & config);
+
+    // Implements SourceSpec
+    SourceFactory::UP createSourceFactory(const TimingValues & timingValues) const;
+
+    /**
+     * Returns the string representation of this config.
+     *
+     * @return the config in a string.
+     */
+    const vespalib::string & toString() const { return _config; }
+private:
+    vespalib::string _config;
+};
+
+/**
+ * A FileSpec gives the ability to serve config from a file. The filenames in
+ * this spec must match the config definition name when subscribing.
+ */
+class FileSpec : public SourceSpec
+{
+public:
+    /**
+     * Creates a FileSpec to serve config from a file. Multiple files may be
+     * added to the spec.
+     *
+     * @param fileName Path to the file to serve config from.
+     */
+    FileSpec(const vespalib::string & fileName);
+
+    /**
+     * Get the file name of this spec.
+     *
+     * @return the filename from which to serve config.
+     */
+    const vespalib::string & getFileName() const { return _fileName; }
+
+    // Implements SourceSpec
+    SourceFactory::UP createSourceFactory(const TimingValues & timingValues) const;
+private:
+    void verifyName(const vespalib::string & fileName);
+    vespalib::string _fileName;
+};
+
+/**
+ * A DirSpec gives the ability to serve config from a directory.
+ */
+class DirSpec : public SourceSpec
+{
+public:
+    /**
+     * Create a DirSpec to serve config from. The files within this directory
+     * must have the names of the config definition ending with a .cfg suffix.
+     *
+     * @param dirName Directory to serve config from.
+     */
+    DirSpec(const vespalib::string & dirName);
+
+    /**
+     * Get directory handled by this spec.
+     *
+     * @return the directory from which to serve config.
+     */
+    const vespalib::string & getDirName() const { return _dirName; }
+
+    // Implements SourceSpec
+    SourceFactory::UP createSourceFactory(const TimingValues & timingValues) const;
+private:
+    vespalib::string _dirName;
+};
+
+/**
+ * A server spec is a user provided specification of one or more config servers
+ * that may provide config.
+ */
+class ServerSpec : public SourceSpec
+{
+public:
+    /// A list of host specifications
+    typedef std::vector<vespalib::string> HostSpecList;
+
+    /**
+     * Construct a ServerSpec that fetches the host specs from the
+     * VESPA_CONFIG_SOURCES environment variable.
+     */
+    ServerSpec();
+
+    /**
+     * Construct a ServerSpec with a list host specifications on the form
+     * tcp/hostname:port
+     *
+     * @param list a list of host specifications.
+     */
+    ServerSpec(const HostSpecList & list);
+
+    /**
+     * Construct a ServerSpec with a host specification.
+     *
+     * @param hostSpec the host specification on the form "tcp/hostname:port"
+     */
+    ServerSpec(const vespalib::string & hostSpec);
+
+    // Implements SourceSpec
+    virtual SourceFactory::UP createSourceFactory(const TimingValues & timingValues) const;
+
+    /**
+     * Add another host to this source spec, allowing failover.
+     *
+     * @param host hostname formatted as tcp/hostname:port
+     */
+    void addHost(const vespalib::string & host) { _hostList.push_back(host); }
+
+    /**
+     * Inspect how many hosts this source refers to.
+     *
+     * @return the number of hosts referred.
+     */
+    size_t numHosts() const { return _hostList.size(); }
+
+    /**
+     * Retrieve host specification element i
+     *
+     * @param i the spec element to retrieve.
+     */
+    const vespalib::string & getHost(size_t i) const { return _hostList[i]; }
+
+    /**
+     * Get the protocol version as parsed by this source spec.
+     */
+    int protocolVersion() const { return _protocolVersion; }
+
+    /**
+     * Get the trace level as parsed by this source spec.
+     */
+    int traceLevel() const { return _traceLevel; }
+
+    /**
+     * Get the compression type as parsed by this source spec.
+     */
+    CompressionType compressionType() const { return _compressionType; }
+private:
+    void initialize(const vespalib::string & hostSpec);
+    HostSpecList _hostList;
+    const int _protocolVersion;
+    const int _traceLevel;
+    const CompressionType _compressionType;
+    const static int DEFAULT_PROXY_PORT = 19090;
+};
+
+
+
+/**
+ * A ConfigSet gives the ability to serve config from a set of ConfigInstance
+ * builders.
+ */
+class ConfigSet : public SourceSpec
+{
+public:
+    /// Constructs a new empty ConfigSet
+    ConfigSet();
+
+    /// Mapping of config keys to builders
+    typedef ConfigSetSourceFactory::BuilderMap BuilderMap;
+    typedef ConfigSetSourceFactory::BuilderMapSP BuilderMapSP;
+    /**
+     * Add a builder to serve config from. The builder must be of a
+     * 'ConfigType'Builder, and the configId must be the id to which you want to
+     * serve the config generated by this builder.
+     *
+     * @param configId The configId that should be used to get the config
+     *                 produced by this builder.
+     * @param builder A builder instance that you can use to change config later
+     *                and then call reload on the ConfigContext object.
+     */
+    void addBuilder(const vespalib::string & configId, ConfigInstance * builder);
+
+    // Implements SourceSpec
+    SourceFactory::UP createSourceFactory(const TimingValues & timingValues) const;
+private:
+    BuilderMapSP _builderMap;
+};
+
+/**
+ * A ConfigInstanceSpec serves a config from a config instance that does not change.
+ */
+class ConfigInstanceSpec : public SourceSpec
+{
+public:
+    ConfigInstanceSpec(const ConfigInstance & instance);
+    SourceFactory::UP createSourceFactory(const TimingValues & timingValues) const;
+private:
+    const ConfigKey _key;
+    vespalib::asciistream _buffer;
+};
+
+}
+
diff --git a/config/src/vespa/config/subscription/subscriptionid.h b/config/src/vespa/config/subscription/subscriptionid.h
new file mode 100644
index 00000000000..00af2a55696
--- /dev/null
+++ b/config/src/vespa/config/subscription/subscriptionid.h
@@ -0,0 +1,10 @@
+// Copyright 2016 Yahoo Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+#pragma once
+#include <vespa/fastos/fastos.h>
+
+namespace config {
+
+typedef uint64_t SubscriptionId;
+
+} // namespace config
+