Let createApplication return an Application (and :dark_sunglasses:)

28 files changed, 1200 insertions, 907 deletions

diff --git a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/ApplicationController.java b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/ApplicationController.java
index ffea3ca2da3..a5e483fa4ce 100644
--- a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/ApplicationController.java
+++ b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/ApplicationController.java
@@ -196,28 +196,39 @@ public class ApplicationController {
         return curator.readApplications();
     }
 
-    /** Returns a snapshot of all applications */
+    /** Returns all applications of a tenant */
+    public List<Application> applicationList(TenantName tenant) {
+        return curator.readApplications(tenant);
+    }
+
+    /** Returns a snapshot of all instances */
     public List<Instance> asList() {
         return curator.readInstances();
     }
 
-    /** Returns all applications of a tenant */
+    /** Returns all instances of a tenant */
     public List<Instance> asList(TenantName tenant) {
         return curator.readInstances(tenant);
     }
 
+    /** Returns all instances of an application */
+    public List<Instance> asList(TenantAndApplicationId id) {
+        return curator.readInstances(id);
+    }
+
     public ArtifactRepository artifacts() { return artifactRepository; }
 
     public ApplicationStore applicationStore() {  return applicationStore; }
 
     /** Returns the oldest Vespa version installed on any active or reserved production node for the given application. */
     public Version oldestInstalledPlatform(ApplicationId id) {
-        return get(id).flatMap(application -> application.productionDeployments().keySet().stream()
-                                                         .flatMap(zone -> configServer.nodeRepository().list(zone, id, EnumSet.of(active, reserved)).stream())
-                                                         .map(Node::currentVersion)
-                                                         .filter(version -> ! version.isEmpty())
-                                                         .min(naturalOrder()))
-                      .orElse(controller.systemVersion());
+        return asList(TenantAndApplicationId.from(id)).stream()
+                                                      .flatMap(instance -> instance.productionDeployments().keySet().stream()
+                                                                                   .flatMap(zone -> configServer.nodeRepository().list(zone, id, EnumSet.of(active, reserved)).stream())
+                                                                                   .map(Node::currentVersion)
+                                                                                   .filter(version -> ! version.isEmpty()))
+                                                      .min(naturalOrder())
+                                                      .orElse(controller.systemVersion());
     }
 
     /** Change the global endpoint status for given deployment */
@@ -256,7 +267,7 @@ public class ApplicationController {
      *
      * @throws IllegalArgumentException if the application already exists
      */
-    public Instance createApplication(ApplicationId id, Optional<Credentials> credentials) {
+    public Application createApplication(ApplicationId id, Optional<Credentials> credentials) {
         if (id.instance().isTester())
             throw new IllegalArgumentException("'" + id + "' is a tester application!");
         try (Lock lock = lock(TenantAndApplicationId.from(id));
@@ -279,7 +290,7 @@ public class ApplicationController {
                 if ( ! id.instance().isTester()) // Only store the application permits for non-user applications.
                     accessControl.createApplication(id, credentials.get());
             }
-            LockedInstance application = new LockedInstance(new Instance(id, clock.instant()), lock);
+            LockedApplication application = new LockedApplication(new Application(id, clock.instant()), lock);
             store(application);
             log.info("Created " + application);
             return application.get();
@@ -757,6 +768,15 @@ public class ApplicationController {
      *
      * @param application a locked application to store
      */
+    public void store(LockedApplication application) {
+        curator.writeApplication(application.get());
+    }
+
+    /**
+     * Replace any previous version of this application by this instance
+     *
+     * @param application a locked application to store
+     */
     public void store(LockedInstance application) {
         curator.writeInstance(application.get());
     }
@@ -767,6 +787,18 @@ public class ApplicationController {
      * @param applicationId ID of the application to lock and get.
      * @param action Function which acts on the locked application.
      */
+    public void lockApplicationIfPresent(ApplicationId applicationId, Consumer<LockedApplication> action) {
+        try (Lock lock = lock(applicationId)) {
+            getApplication(applicationId).map(application -> new LockedApplication(application, lock)).ifPresent(action);
+        }
+    }
+
+    /**
+     * Acquire a locked instance to modify and store, if there is an instance with the given id.
+     *
+     * @param applicationId ID of the instance to lock and get.
+     * @param action Function which acts on the locked instance.
+     */
     public void lockIfPresent(ApplicationId applicationId, Consumer<LockedInstance> action) {
         try (Lock lock = lock(TenantAndApplicationId.from(applicationId));
              Lock oldLock = lock(applicationId)) {
@@ -781,6 +813,19 @@ public class ApplicationController {
      * @param action Function which acts on the locked application.
      * @throws IllegalArgumentException when application does not exist.
      */
+    public void lockApplicationOrThrow(ApplicationId applicationId, Consumer<LockedApplication> action) {
+        try (Lock lock = lock(applicationId)) {
+            action.accept(new LockedApplication(requireApplication(applicationId), lock));
+        }
+    }
+
+    /**
+     * Acquire a locked instance to modify and store, or throw an exception if no instance has the given id.
+     *
+     * @param applicationId ID of the instance to lock and require.
+     * @param action Function which acts on the locked instance.
+     * @throws IllegalArgumentException when instance does not exist.
+     */
     public void lockOrThrow(ApplicationId applicationId, Consumer<LockedInstance> action) {
         try (Lock lock = lock(TenantAndApplicationId.from(applicationId));
              Lock oldLock = lock(applicationId)) {
diff --git a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/LockedApplication.java b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/LockedApplication.java
index c3a710ec530..a6fce4bb0c4 100644
--- a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/LockedApplication.java
+++ b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/LockedApplication.java
@@ -96,8 +96,8 @@ public class LockedApplication {
     }
 
     /** Returns a read-only copy of this */
-    public Instance get() {
-        return new Instance(id, createdAt, deploymentSpec, validationOverrides, deployments, deploymentJobs, change,
+    public Application get() {
+        return new Application(id, createdAt, deploymentSpec, validationOverrides, deployments, deploymentJobs, change,
                             outstandingChange, ownershipIssueId, owner, majorVersion, metrics, pemDeployKey,
                             rotations, rotationStatus);
     }
diff --git a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/RoutingPolicies.java b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/RoutingPolicies.java
index b2006c4c1f4..d6080bcda6c 100644
--- a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/RoutingPolicies.java
+++ b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/maintenance/RoutingPolicies.java
@@ -51,7 +51,7 @@ public class RoutingPolicies {
         }
     }
 
-    /** Read all known routing policies for given application */
+    /** Read all known routing policies for given instance */
     public Set<RoutingPolicy> get(ApplicationId application) {
         return db.readRoutingPolicies(application);
     }
diff --git a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/persistence/CuratorDb.java b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/persistence/CuratorDb.java
index 9c5eb9db465..263429952d9 100644
--- a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/persistence/CuratorDb.java
+++ b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/persistence/CuratorDb.java
@@ -359,6 +359,7 @@ public class CuratorDb {
     }
 
     private Stream<ApplicationId> readApplicationIds() {
+        // TODO jonmv: Filter on number of parts in id when reading from applicationRoot again.
         return curator.getChildren(instanceRoot).stream().map(ApplicationId::fromSerializedForm);
     }
 
@@ -394,7 +395,12 @@ public class CuratorDb {
     }
 
     public List<Instance> readInstances(TenantName name) {
-        return readInstances(application -> application.tenant().equals(name));
+        return readInstances(instance -> instance.tenant().equals(name));
+    }
+
+    public List<Instance> readInstances(TenantAndApplicationId id) {
+        return readInstances(instance ->    instance.tenant().equals(id.tenant())
+                                         && instance.application().equals(id.application()));
     }
 
     private Stream<ApplicationId> readInstanceIds() {
@@ -430,7 +436,7 @@ public class CuratorDb {
      * Use Application where applicable
      *
      * Stop writing Instance to old application path
-     * Read Application from application path
+     * Read Application and Instance parts from respective paths
      *
      * Stop writing instance part to application path, and vice versa
      * Remove unused parts of Instance and Application
diff --git a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/restapi/application/ApplicationApiHandler.java b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/restapi/application/ApplicationApiHandler.java
index 123da447757..7585d372bc1 100644
--- a/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/restapi/application/ApplicationApiHandler.java
+++ b/controller-server/src/main/java/com/yahoo/vespa/hosted/controller/restapi/application/ApplicationApiHandler.java
@@ -26,6 +26,7 @@ import com.yahoo.vespa.athenz.api.AthenzUser;
 import com.yahoo.vespa.athenz.client.zms.ZmsClientException;
 import com.yahoo.vespa.config.SlimeUtils;
 import com.yahoo.vespa.hosted.controller.AlreadyExistsException;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Instance;
 import com.yahoo.vespa.hosted.controller.Controller;
 import com.yahoo.vespa.hosted.controller.NotExistsException;
@@ -475,6 +476,150 @@ public class ApplicationApiHandler extends LoggingRequestHandler {
         return new MessageResponse(type.jobName() + " for " + id + " paused for " + DeploymentTrigger.maxPause);
     }
 
+    private void toSlime(Cursor object, Application application, HttpRequest request) {
+        object.setString("tenant", application.id().tenant().value());
+        object.setString("application", application.id().application().value());
+        object.setString("instance", application.id().instance().value());
+        object.setString("deployments", withPath("/application/v4" +
+                                                 "/tenant/" + application.id().tenant().value() +
+                                                 "/application/" + application.id().application().value() +
+                                                 "/instance/" + application.id().instance().value() + "/job/",
+                                                 request.getUri()).toString());
+
+        application.deploymentJobs().statusOf(JobType.component)
+                .flatMap(JobStatus::lastSuccess)
+                .map(run -> run.application().source())
+                .ifPresent(source -> sourceRevisionToSlime(source, object.setObject("source")));
+
+        application.deploymentJobs().projectId()
+                .ifPresent(id -> object.setLong("projectId", id));
+
+        // Currently deploying change
+        if ( ! application.change().isEmpty()) {
+            toSlime(object.setObject("deploying"), application.change());
+        }
+
+        // Outstanding change
+        if ( ! application.outstandingChange().isEmpty()) {
+            toSlime(object.setObject("outstandingChange"), application.outstandingChange());
+        }
+
+        // Jobs sorted according to deployment spec
+        List<JobStatus> jobStatus = controller.applications().deploymentTrigger()
+                                              .steps(application.deploymentSpec())
+                                              .sortedJobs(application.deploymentJobs().jobStatus().values());
+
+        object.setBool("deployedInternally", application.deploymentJobs().deployedInternally());
+        Cursor deploymentsArray = object.setArray("deploymentJobs");
+        for (JobStatus job : jobStatus) {
+            Cursor jobObject = deploymentsArray.addObject();
+            jobObject.setString("type", job.type().jobName());
+            jobObject.setBool("success", job.isSuccess());
+
+            job.lastTriggered().ifPresent(jobRun -> toSlime(jobRun, jobObject.setObject("lastTriggered")));
+            job.lastCompleted().ifPresent(jobRun -> toSlime(jobRun, jobObject.setObject("lastCompleted")));
+            job.firstFailing().ifPresent(jobRun -> toSlime(jobRun, jobObject.setObject("firstFailing")));
+            job.lastSuccess().ifPresent(jobRun -> toSlime(jobRun, jobObject.setObject("lastSuccess")));
+        }
+
+        // Change blockers
+        Cursor changeBlockers = object.setArray("changeBlockers");
+        application.deploymentSpec().changeBlocker().forEach(changeBlocker -> {
+            Cursor changeBlockerObject = changeBlockers.addObject();
+            changeBlockerObject.setBool("versions", changeBlocker.blocksVersions());
+            changeBlockerObject.setBool("revisions", changeBlocker.blocksRevisions());
+            changeBlockerObject.setString("timeZone", changeBlocker.window().zone().getId());
+            Cursor days = changeBlockerObject.setArray("days");
+            changeBlocker.window().days().stream().map(DayOfWeek::getValue).forEach(days::addLong);
+            Cursor hours = changeBlockerObject.setArray("hours");
+            changeBlocker.window().hours().forEach(hours::addLong);
+        });
+
+        // Compile version. The version that should be used when building an application
+        object.setString("compileVersion", compileVersion(application.id()).toFullString());
+
+        application.majorVersion().ifPresent(majorVersion -> object.setLong("majorVersion", majorVersion));
+
+        // Rotation
+        Cursor globalRotationsArray = object.setArray("globalRotations");
+        application.endpointsIn(controller.system())
+                .scope(Endpoint.Scope.global)
+                .legacy(false) // Hide legacy names
+                .asList().stream()
+                .map(Endpoint::url)
+                .map(URI::toString)
+                .forEach(globalRotationsArray::addString);
+
+        application.rotations().stream()
+                .map(AssignedRotation::rotationId)
+                .findFirst()
+                .ifPresent(rotation -> object.setString("rotationId", rotation.asString()));
+
+        // Per-cluster rotations
+        Set<RoutingPolicy> routingPolicies = controller.applications().routingPolicies().get(application.id());
+        for (RoutingPolicy policy : routingPolicies) {
+            policy.rotationEndpointsIn(controller.system()).asList().stream()
+                  .map(Endpoint::url)
+                  .map(URI::toString)
+                  .forEach(globalRotationsArray::addString);
+        }
+
+        // Deployments sorted according to deployment spec
+        List<Deployment> deployments = controller.applications().deploymentTrigger()
+                                                 .steps(application.deploymentSpec())
+                                                 .sortedDeployments(application.deployments().values());
+        Cursor instancesArray = object.setArray("instances");
+        for (Deployment deployment : deployments) {
+            Cursor deploymentObject = instancesArray.addObject();
+
+            // Rotation status for this deployment
+            if (deployment.zone().environment() == Environment.prod) {
+                //  0 rotations: No fields written
+                //  1 rotation : Write legacy field and endpointStatus field
+                // >1 rotation : Write only endpointStatus field
+                if (application.rotations().size() == 1) {
+                    // TODO(mpolden): Stop writing this field once clients stop expecting it
+                    toSlime(application.rotationStatus().of(application.rotations().get(0).rotationId(), deployment),
+                            deploymentObject);
+                }
+                if (!application.rotations().isEmpty()) {
+                    toSlime(application.rotations(), application.rotationStatus(), deployment, deploymentObject);
+                }
+            }
+
+            if (recurseOverDeployments(request)) // List full deployment information when recursive.
+                toSlime(deploymentObject, new DeploymentId(application.id(), deployment.zone()), deployment, request);
+            else {
+                deploymentObject.setString("environment", deployment.zone().environment().value());
+                deploymentObject.setString("region", deployment.zone().region().value());
+                deploymentObject.setString("instance", application.id().instance().value()); // pointless
+                deploymentObject.setString("url", withPath(request.getUri().getPath() +
+                                                           "/environment/" + deployment.zone().environment().value() +
+                                                           "/region/" + deployment.zone().region().value() +
+                                                           ( request.getUri().getPath().contains("/instance/") ? "" : "/instance/" + application.id().instance().value()),
+                                                           request.getUri()).toString());
+            }
+        }
+
+        application.pemDeployKey().ifPresent(key -> object.setString("pemDeployKey", key));
+
+        // Metrics
+        Cursor metricsObject = object.setObject("metrics");
+        metricsObject.setDouble("queryServiceQuality", application.metrics().queryServiceQuality());
+        metricsObject.setDouble("writeServiceQuality", application.metrics().writeServiceQuality());
+
+        // Activity
+        Cursor activity = object.setObject("activity");
+        application.activity().lastQueried().ifPresent(instant -> activity.setLong("lastQueried", instant.toEpochMilli()));
+        application.activity().lastWritten().ifPresent(instant -> activity.setLong("lastWritten", instant.toEpochMilli()));
+        application.activity().lastQueriesPerSecond().ifPresent(value -> activity.setDouble("lastQueriesPerSecond", value));
+        application.activity().lastWritesPerSecond().ifPresent(value -> activity.setDouble("lastWritesPerSecond", value));
+
+        application.ownershipIssueId().ifPresent(issueId -> object.setString("ownershipIssueId", issueId.value()));
+        application.owner().ifPresent(owner -> object.setString("owner", owner.username()));
+        application.deploymentJobs().issueId().ifPresent(issueId -> object.setString("deploymentIssueId", issueId.value()));
+    }
+
     private void toSlime(Cursor object, Instance instance, HttpRequest request) {
         object.setString("tenant", instance.id().tenant().value());
         object.setString("application", instance.id().application().value());
@@ -968,10 +1113,10 @@ public class ApplicationApiHandler extends LoggingRequestHandler {
             Optional<Credentials> credentials = controller.tenants().require(id.tenant()).type() == Tenant.Type.user
                     ? Optional.empty()
                     : Optional.of(accessControlRequests.credentials(id.tenant(), requestObject, request.getJDiscRequest()));
-            Instance instance = controller.applications().createApplication(id, credentials);
+            Application application = controller.applications().createApplication(id, credentials);
 
             Slime slime = new Slime();
-            toSlime(instance, slime.setObject(), request);
+            toSlime(application, slime.setObject(), request);
             return new SlimeJsonResponse(slime);
         }
         catch (ZmsClientException e) { // TODO: Push conversion down
@@ -1391,6 +1536,17 @@ public class ApplicationApiHandler extends LoggingRequestHandler {
         return Joiner.on("/").join(elements);
     }
 
+    private void toSlime(Application application, Cursor object, HttpRequest request) {
+        object.setString("tenant", application.id().tenant().value());
+        object.setString("application", application.id().application().value());
+        object.setString("instance", application.id().instance().value());
+        object.setString("url", withPath("/application/v4" +
+                                         "/tenant/" + application.id().tenant().value() +
+                                         "/application/" + application.id().application().value() +
+                                         "/instance/" + application.id().instance().value(),
+                                         request.getUri()).toString());
+    }
+
     private void toSlime(Instance instance, Cursor object, HttpRequest request) {
         object.setString("tenant", instance.id().tenant().value());
         object.setString("application", instance.id().application().value());
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/ControllerTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/ControllerTest.java
index 57994e181c5..961c1746b39 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/ControllerTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/ControllerTest.java
@@ -35,6 +35,8 @@ import com.yahoo.vespa.hosted.controller.deployment.ApplicationPackageBuilder;
 import com.yahoo.vespa.hosted.controller.deployment.BuildJob;
 import com.yahoo.vespa.hosted.controller.deployment.DeploymentTester;
 import com.yahoo.vespa.hosted.controller.integration.ZoneApiMock;
+import com.yahoo.vespa.hosted.controller.persistence.ApplicationSerializer;
+import com.yahoo.vespa.hosted.controller.persistence.InstanceSerializer;
 import com.yahoo.vespa.hosted.controller.persistence.MockCuratorDb;
 import com.yahoo.vespa.hosted.controller.persistence.OldMockCuratorDb;
 import com.yahoo.vespa.hosted.controller.rotation.RotationId;
@@ -85,13 +87,14 @@ public class ControllerTest {
 
         // staging job - succeeding
         Version version1 = tester.defaultPlatformVersion();
-        Instance app1 = tester.createApplication("app1", "tenant1", 1, 11L);
+        Application app1 = tester.createApplication("app1", "tenant1", 1, 11L);
+        Instance instance = tester.instance(app1.id());
         tester.jobCompletion(component).application(app1).uploadArtifact(applicationPackage).submit();
         assertEquals("Application version is known from completion of initial job",
                      ApplicationVersion.from(BuildJob.defaultSourceRevision, BuildJob.defaultBuildNumber),
                      tester.controller().applications().require(app1.id()).change().application().get());
-        tester.deployAndNotify(app1, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app1, applicationPackage, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
         assertEquals(4, applications.require(app1.id()).deploymentJobs().jobStatus().size());
 
         ApplicationVersion applicationVersion = tester.controller().applications().require(app1.id()).change().application().get();
@@ -106,8 +109,8 @@ public class ControllerTest {
         tester.clock().advance(Duration.ofSeconds(1));
 
         // production job (failing) after deployment
-        tester.deploy(productionUsWest1, app1, applicationPackage);
-        tester.deployAndNotify(app1, applicationPackage, false, productionUsWest1);
+        tester.deploy(productionUsWest1, instance.id(), applicationPackage);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, productionUsWest1);
         assertEquals(4, applications.require(app1.id()).deploymentJobs().jobStatus().size());
 
         JobStatus expectedJobStatus = JobStatus.initial(productionUsWest1)
@@ -115,7 +118,7 @@ public class ControllerTest {
                                                .withCompletion(42, Optional.of(JobError.unknown), tester.clock().instant().truncatedTo(MILLIS))
                                                .withTriggering(version1,
                                                                applicationVersion,
-                                                               Optional.of(tester.application(app1.id()).deployments().get(productionUsWest1.zone(main))),
+                                                               Optional.of(tester.instance(app1.id()).deployments().get(productionUsWest1.zone(main))),
                                                                "",
                                                                tester.clock().instant().truncatedTo(MILLIS)); // Re-triggering (due to failure) has application version info
 
@@ -137,28 +140,28 @@ public class ControllerTest {
 
         // system and staging test job - succeeding
         tester.jobCompletion(component).application(app1).nextBuildNumber().uploadArtifact(applicationPackage).submit();
-        applicationVersion = tester.application("app1").change().application().get();
-        tester.deployAndNotify(app1, applicationPackage, true, systemTest);
+        applicationVersion = tester.instance("app1").change().application().get();
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
         assertStatus(JobStatus.initial(systemTest)
-                              .withTriggering(version1, applicationVersion, Optional.of(tester.application(app1.id()).deployments().get(productionUsWest1.zone(main))), "", tester.clock().instant().truncatedTo(MILLIS))
+                              .withTriggering(version1, applicationVersion, Optional.of(tester.instance(app1.id()).deployments().get(productionUsWest1.zone(main))), "", tester.clock().instant().truncatedTo(MILLIS))
                               .withCompletion(42, Optional.empty(), tester.clock().instant().truncatedTo(MILLIS)),
                      app1.id(), tester.controller());
         tester.clock().advance(Duration.ofHours(1)); // Stop retrying
         tester.jobCompletion(productionUsWest1).application(app1).unsuccessful().submit();
-        tester.deployAndNotify(app1, applicationPackage, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
 
         // production job succeeding now
         expectedJobStatus = expectedJobStatus
-                .withTriggering(version1, applicationVersion, Optional.of(tester.application(app1.id()).deployments().get(productionUsWest1.zone(main))), "", tester.clock().instant().truncatedTo(MILLIS))
+                .withTriggering(version1, applicationVersion, Optional.of(tester.instance(app1.id()).deployments().get(productionUsWest1.zone(main))), "", tester.clock().instant().truncatedTo(MILLIS))
                 .withCompletion(42, Optional.empty(), tester.clock().instant().truncatedTo(MILLIS));
-        tester.deployAndNotify(app1, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsWest1);
         assertStatus(expectedJobStatus, app1.id(), tester.controller());
 
         // causes triggering of next production job
         assertStatus(JobStatus.initial(productionUsEast3)
                               .withTriggering(version1, applicationVersion, Optional.empty(), "", tester.clock().instant().truncatedTo(MILLIS)),
                      app1.id(), tester.controller());
-        tester.deployAndNotify(app1, applicationPackage, true, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsEast3);
 
         assertEquals(5, applications.get(app1.id()).get().deploymentJobs().jobStatus().size());
 
@@ -183,7 +186,7 @@ public class ControllerTest {
                 .build();
         tester.jobCompletion(component).application(app1).nextBuildNumber().nextBuildNumber().uploadArtifact(applicationPackage).submit();
         try {
-            tester.deploy(systemTest, app1, applicationPackage);
+            tester.deploy(systemTest, instance.id(), applicationPackage);
             fail("Expected exception due to illegal production deployment removal");
         }
         catch (IllegalArgumentException e) {
@@ -206,7 +209,7 @@ public class ControllerTest {
                 .region("us-east-3")
                 .build();
         tester.jobCompletion(component).application(app1).nextBuildNumber(2).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app1, applicationPackage, true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
         assertNull("Zone was removed",
                    applications.require(app1.id()).deployments().get(productionUsWest1.zone(main)));
         assertNull("Deployment job was removed", applications.require(app1.id()).deploymentJobs().jobStatus().get(productionUsWest1));
@@ -214,7 +217,7 @@ public class ControllerTest {
 
     @Test
     public void testDeploymentApplicationVersion() {
-        Instance app = tester.createApplication("app1", "tenant1", 1, 11L);
+        Application app = tester.createApplication("app1", "tenant1", 1, 11L);
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-west-1")
@@ -282,7 +285,7 @@ public class ControllerTest {
 
     @Test
     public void testDnsAliasRegistration() {
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
+        Application application = tester.createApplication("app1", "tenant1", 1, 1L);
 
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
@@ -291,14 +294,14 @@ public class ControllerTest {
                 .region("us-central-1") // Two deployments should result in each DNS alias being registered once
                 .build();
 
-        tester.deployCompletely(instance, applicationPackage);
-        Collection<Deployment> deployments = tester.application(instance.id()).deployments().values();
+        tester.deployCompletely(application, applicationPackage);
+        Collection<Deployment> deployments = tester.instance(application.id()).deployments().values();
         assertFalse(deployments.isEmpty());
         for (Deployment deployment : deployments) {
             assertEquals("Rotation names are passed to config server in " + deployment.zone(),
                          Set.of("rotation-id-01",
                                 "app1--tenant1.global.vespa.oath.cloud"),
-                         tester.configServer().rotationNames().get(new DeploymentId(instance.id(), deployment.zone())));
+                         tester.configServer().rotationNames().get(new DeploymentId(application.id(), deployment.zone())));
         }
         tester.flushDnsRequests();
 
@@ -312,7 +315,7 @@ public class ControllerTest {
 
     @Test
     public void testDnsAliasRegistrationLegacy() {
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
+        Application application = tester.createApplication("app1", "tenant1", 1, 1L);
 
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
@@ -321,8 +324,8 @@ public class ControllerTest {
                 .region("us-central-1") // Two deployments should result in each DNS alias being registered once
                 .build();
 
-        tester.deployCompletely(instance, applicationPackage);
-        Collection<Deployment> deployments = tester.application(instance.id()).deployments().values();
+        tester.deployCompletely(application, applicationPackage);
+        Collection<Deployment> deployments = tester.instance(application.id()).deployments().values();
         assertFalse(deployments.isEmpty());
         for (Deployment deployment : deployments) {
             assertEquals("Rotation names are passed to config server in " + deployment.zone(),
@@ -330,7 +333,7 @@ public class ControllerTest {
                             "app1--tenant1.global.vespa.oath.cloud",
                             "app1.tenant1.global.vespa.yahooapis.com",
                             "app1--tenant1.global.vespa.yahooapis.com"),
-                    tester.configServer().rotationNames().get(new DeploymentId(instance.id(), deployment.zone())));
+                    tester.configServer().rotationNames().get(new DeploymentId(application.id(), deployment.zone())));
         }
         tester.flushDnsRequests();
         assertEquals(3, tester.controllerTester().nameService().records().size());
@@ -353,7 +356,7 @@ public class ControllerTest {
 
     @Test
     public void testDnsAliasRegistrationWithEndpoints() {
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
+        Application application = tester.createApplication("app1", "tenant1", 1, 1L);
 
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
@@ -365,8 +368,8 @@ public class ControllerTest {
                 .region("us-central-1")
                 .build();
 
-        tester.deployCompletely(instance, applicationPackage);
-        Collection<Deployment> deployments = tester.application(instance.id()).deployments().values();
+        tester.deployCompletely(application, applicationPackage);
+        Collection<Deployment> deployments = tester.instance(application.id()).deployments().values();
         assertFalse(deployments.isEmpty());
 
         var notWest = Set.of(
@@ -379,7 +382,7 @@ public class ControllerTest {
         for (Deployment deployment : deployments) {
             assertEquals("Rotation names are passed to config server in " + deployment.zone(),
                     ZoneId.from("prod.us-west-1").equals(deployment.zone()) ? west : notWest,
-                    tester.configServer().rotationNames().get(new DeploymentId(instance.id(), deployment.zone())));
+                    tester.configServer().rotationNames().get(new DeploymentId(application.id(), deployment.zone())));
         }
         tester.flushDnsRequests();
 
@@ -408,7 +411,7 @@ public class ControllerTest {
 
     @Test
     public void testDnsAliasRegistrationWithChangingZones() {
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
+        Application application = tester.createApplication("app1", "tenant1", 1, 1L);
 
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
@@ -417,16 +420,16 @@ public class ControllerTest {
                 .region("us-central-1")
                 .build();
 
-        tester.deployCompletely(instance, applicationPackage);
+        tester.deployCompletely(application, applicationPackage);
 
         assertEquals(
                 Set.of("rotation-id-01", "app1--tenant1.global.vespa.oath.cloud"),
-                tester.configServer().rotationNames().get(new DeploymentId(instance.id(), ZoneId.from("prod", "us-west-1")))
+                tester.configServer().rotationNames().get(new DeploymentId(application.id(), ZoneId.from("prod", "us-west-1")))
         );
 
         assertEquals(
                 Set.of("rotation-id-01", "app1--tenant1.global.vespa.oath.cloud"),
-                tester.configServer().rotationNames().get(new DeploymentId(instance.id(), ZoneId.from("prod", "us-central-1")))
+                tester.configServer().rotationNames().get(new DeploymentId(application.id(), ZoneId.from("prod", "us-central-1")))
         );
 
 
@@ -437,24 +440,24 @@ public class ControllerTest {
                 .region("us-central-1")
                 .build();
 
-        tester.deployCompletely(instance, applicationPackage2, BuildJob.defaultBuildNumber + 1);
+        tester.deployCompletely(application, applicationPackage2, BuildJob.defaultBuildNumber + 1);
 
         assertEquals(
                 Set.of("rotation-id-01", "app1--tenant1.global.vespa.oath.cloud"),
-                tester.configServer().rotationNames().get(new DeploymentId(instance.id(), ZoneId.from("prod", "us-west-1")))
+                tester.configServer().rotationNames().get(new DeploymentId(application.id(), ZoneId.from("prod", "us-west-1")))
         );
 
         assertEquals(
                 Set.of(),
-                tester.configServer().rotationNames().get(new DeploymentId(instance.id(), ZoneId.from("prod", "us-central-1")))
+                tester.configServer().rotationNames().get(new DeploymentId(application.id(), ZoneId.from("prod", "us-central-1")))
         );
 
-        assertEquals(Set.of(RegionName.from("us-west-1")), tester.application(instance.id()).rotations().get(0).regions());
+        assertEquals(Set.of(RegionName.from("us-west-1")), tester.instance(application.id()).rotations().get(0).regions());
     }
 
     @Test
     public void testUnassignRotations() {
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
+        Application application = tester.createApplication("app1", "tenant1", 1, 1L);
 
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
@@ -463,7 +466,7 @@ public class ControllerTest {
                 .region("us-central-1") // Two deployments should result in each DNS alias being registered once
                 .build();
 
-        tester.deployCompletely(instance, applicationPackage);
+        tester.deployCompletely(application, applicationPackage);
 
         ApplicationPackage applicationPackage2 = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
@@ -471,17 +474,17 @@ public class ControllerTest {
                 .region("us-central-1") // Two deployments should result in each DNS alias being registered once
                 .build();
 
-        tester.deployCompletely(instance, applicationPackage2, BuildJob.defaultBuildNumber + 1);
+        tester.deployCompletely(application, applicationPackage2, BuildJob.defaultBuildNumber + 1);
 
 
         assertEquals(
                 List.of(AssignedRotation.fromStrings("qrs", "default", "rotation-id-01", Set.of())),
-                tester.application(instance.id()).rotations()
+                tester.instance(application.id()).rotations()
         );
 
         assertEquals(
                 Set.of(),
-                tester.configServer().rotationNames().get(new DeploymentId(instance.id(), ZoneId.from("prod", "us-west-1")))
+                tester.configServer().rotationNames().get(new DeploymentId(application.id(), ZoneId.from("prod", "us-west-1")))
         );
     }
 
@@ -489,7 +492,7 @@ public class ControllerTest {
     public void testUpdatesExistingDnsAlias() {
         // Application 1 is deployed and deleted
         {
-            Instance app1 = tester.createApplication("app1", "tenant1", 1, 1L);
+            Application app1 = tester.createApplication("app1", "tenant1", 1, 1L);
             ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                     .environment(Environment.prod)
                     .endpoint("default", "foo")
@@ -511,7 +514,7 @@ public class ControllerTest {
                     .allow(ValidationId.deploymentRemoval)
                     .build();
             tester.jobCompletion(component).application(app1).nextBuildNumber().uploadArtifact(applicationPackage).submit();
-            tester.deployAndNotify(app1, applicationPackage, true, systemTest);
+            tester.deployAndNotify(tester.instance(app1.id()).id(), Optional.of(applicationPackage), true, systemTest);
             tester.applications().deactivate(app1.id(), ZoneId.from(Environment.test, RegionName.from("us-east-1")));
             tester.applications().deactivate(app1.id(), ZoneId.from(Environment.staging, RegionName.from("us-east-3")));
             tester.applications().deleteApplication(app1.id().tenant(), app1.id().application(), tester.controllerTester().credentialsFor(app1.id()));
@@ -535,7 +538,7 @@ public class ControllerTest {
 
         // Application 2 is deployed and assigned same rotation as application 1 had before deletion
         {
-            Instance app2 = tester.createApplication("app2", "tenant2", 2, 1L);
+            Application app2 = tester.createApplication("app2", "tenant2", 2, 1L);
             ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                     .environment(Environment.prod)
                     .endpoint("default", "foo")
@@ -554,7 +557,7 @@ public class ControllerTest {
         // Application 1 is recreated, deployed and assigned a new rotation
         {
             tester.buildService().clear();
-            Instance app1 = tester.createApplication("app1", "tenant1", 1, 1L);
+            Application app1 = tester.createApplication("app1", "tenant1", 1, 1L);
             ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                     .environment(Environment.prod)
                     .endpoint("default", "foo")
@@ -562,8 +565,7 @@ public class ControllerTest {
                     .region("us-central-1")
                     .build();
             tester.deployCompletely(app1, applicationPackage);
-            app1 = tester.applications().require(app1.id());
-            assertEquals("rotation-id-02", app1.rotations().get(0).rotationId().asString());
+            assertEquals("rotation-id-02", tester.instance(app1.id()).rotations().get(0).rotationId().asString());
 
             // DNS records are created for the newly assigned rotation
             assertEquals(2, tester.controllerTester().nameService().records().size());
@@ -592,7 +594,7 @@ public class ControllerTest {
                 .build();
 
         // Create application
-        Instance app = tester.createApplication("app1", "tenant1", 1, 2L);
+        Application app = tester.createApplication("app1", "tenant1", 1, 2L);
 
         // Direct deploy is allowed when deployDirectly is true
         ZoneId zone = ZoneId.from("prod", "cd-us-central-1");
@@ -610,7 +612,7 @@ public class ControllerTest {
         Version seven = Version.fromString("7.2");
         tester.upgradeSystem(seven);
         tester.controller().applications().deploy(app.id(), zone, Optional.of(applicationPackage), options);
-        assertEquals(six, tester.application(app.id()).deployments().get(zone).version());
+        assertEquals(six, tester.instance(app.id()).deployments().get(zone).version());
     }
 
     @Test
@@ -622,7 +624,7 @@ public class ControllerTest {
                 .build();
 
         // Create application
-        Instance app = tester.createApplication("app1", "tenant1", 1, 2L);
+        Application app = tester.createApplication("app1", "tenant1", 1, 2L);
         ZoneId zone = ZoneId.from("dev", "us-east-1");
 
         // Deploy
@@ -636,7 +638,7 @@ public class ControllerTest {
 
     @Test
     public void testSuspension() {
-        Instance app = tester.createApplication("app1", "tenant1", 1, 11L);
+        Application app = tester.createApplication("app1", "tenant1", 1, 11L);
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                                                         .environment(Environment.prod)
                                                         .region("us-west-1")
@@ -660,7 +662,7 @@ public class ControllerTest {
     // second time will not fail
     @Test
     public void testDeletingApplicationThatHasAlreadyBeenDeleted() {
-        Instance app = tester.createApplication("app2", "tenant1", 1, 12L);
+        Application app = tester.createApplication("app2", "tenant1", 1, 12L);
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-east-3")
@@ -675,7 +677,7 @@ public class ControllerTest {
 
     @Test
     public void testDeployApplicationPackageWithApplicationDir() {
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
+        Application instance = tester.createApplication("app1", "tenant1", 1, 1L);
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-west-1")
@@ -685,7 +687,7 @@ public class ControllerTest {
 
     @Test
     public void testDeployApplicationWithWarnings() {
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
+        Application instance = tester.createApplication("app1", "tenant1", 1, 1L);
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-west-1")
@@ -710,7 +712,8 @@ public class ControllerTest {
                                                                                .build();
         // Deploy app1 in production
         tester.deployCompletely(app1, applicationPackage);
-        var cert = certificate.apply(app1);
+        Instance instance1 = tester.instance(app1.id());
+        var cert = certificate.apply(instance1);
         assertTrue("Provisions certificate in " + Environment.prod, cert.isPresent());
         assertEquals(List.of(
                 "vznqtz7a5ygwjkbhhj7ymxvlrekgt4l6g.vespa.oath.cloud",
@@ -728,17 +731,18 @@ public class ControllerTest {
 
         // Next deployment reuses certificate
         tester.deployCompletely(app1, applicationPackage, BuildJob.defaultBuildNumber + 1);
-        assertEquals(cert, certificate.apply(app1));
+        assertEquals(cert, certificate.apply(instance1));
 
         // Create app2
         var app2 = tester.createApplication("app2", "tenant2", 3, 4L);
+        Instance instance2 = tester.instance(app2.id());
         ZoneId zone = ZoneId.from("dev", "us-east-1");
 
         // Deploy app2 in dev
         tester.controller().applications().deploy(app2.id(), zone, Optional.of(applicationPackage), DeployOptions.none());
         assertTrue("Application deployed and activated",
                    tester.controllerTester().configServer().application(app2.id(), zone).get().activated());
-        assertFalse("Does not provision certificate in " + Environment.dev, certificate.apply(app2).isPresent());
+        assertFalse("Does not provision certificate in " + Environment.dev, certificate.apply(instance2).isPresent());
     }
 
     @Test
@@ -805,6 +809,15 @@ public class ControllerTest {
         newDb.writeInstance(instance2);
         assertEquals(instance2, oldDb.readInstance(instance2.id()).orElseThrow());
         assertEquals(instance2, newDb.readInstance(instance2.id()).orElseThrow());
+
+        Application application = newDb.readApplication(instance1.id()).orElseThrow();
+        assertEquals(new ApplicationSerializer().toSlime(application).toString(),
+                     new InstanceSerializer().toSlime(instance1).toString());
+
+        oldDb.removeInstance(instance1.id());
+        newDb.removeInstance(instance2.id());
+        assertEquals(List.of(), oldDb.readInstances());
+        assertEquals(List.of(), newDb.readInstances());
     }
 
     private void runUpgrade(DeploymentTester tester, ApplicationId application, ApplicationVersion version) {
@@ -813,11 +826,11 @@ public class ControllerTest {
         runDeployment(tester, tester.applications().require(application), version, Optional.of(next), Optional.empty());
     }
 
-    private void runDeployment(DeploymentTester tester, ApplicationId application, ApplicationVersion version,
+    private void runDeployment(DeploymentTester tester, ApplicationId id, ApplicationVersion version,
                                ApplicationPackage applicationPackage, SourceRevision sourceRevision, long buildNumber) {
-        Instance app = tester.applications().require(application);
+        Instance instance = tester.applications().require(id);
         tester.jobCompletion(component)
-              .application(app)
+              .application(tester.application(id))
               .buildNumber(buildNumber)
               .sourceRevision(sourceRevision)
               .uploadArtifact(applicationPackage)
@@ -825,9 +838,9 @@ public class ControllerTest {
 
         ApplicationVersion change = ApplicationVersion.from(sourceRevision, buildNumber);
         assertEquals(change.id(), tester.controller().applications()
-                                        .require(application)
+                                        .require(id)
                                         .change().application().get().id());
-        runDeployment(tester, app, version, Optional.empty(), Optional.of(applicationPackage));
+        runDeployment(tester, instance, version, Optional.empty(), Optional.of(applicationPackage));
     }
 
     private void assertStatus(JobStatus expectedStatus, ApplicationId id, Controller controller) {
@@ -842,27 +855,27 @@ public class ControllerTest {
         Version vespaVersion = upgrade.orElseGet(tester::defaultPlatformVersion);
 
         // Deploy in test
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
+        tester.deployAndNotify(app.id(), applicationPackage, true, systemTest);
+        tester.deployAndNotify(app.id(), applicationPackage, true, stagingTest);
         JobStatus expected = JobStatus.initial(stagingTest)
-                                      .withTriggering(vespaVersion, version, Optional.ofNullable(tester.application(app.id()).deployments().get(productionUsWest1.zone(main))), "",
+                                      .withTriggering(vespaVersion, version, Optional.ofNullable(tester.instance(app.id()).deployments().get(productionUsWest1.zone(main))), "",
                                                       tester.clock().instant().truncatedTo(MILLIS))
                                       .withCompletion(42, Optional.empty(), tester.clock().instant().truncatedTo(MILLIS));
         assertStatus(expected, app.id(), tester.controller());
 
         // Deploy in production
         expected = JobStatus.initial(productionUsWest1)
-                            .withTriggering(vespaVersion, version, Optional.ofNullable(tester.application(app.id()).deployments().get(productionUsWest1.zone(main))), "",
+                            .withTriggering(vespaVersion, version, Optional.ofNullable(tester.instance(app.id()).deployments().get(productionUsWest1.zone(main))), "",
                                             tester.clock().instant().truncatedTo(MILLIS))
                             .withCompletion(42, Optional.empty(), tester.clock().instant().truncatedTo(MILLIS));
-        tester.deployAndNotify(app, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(app.id(), applicationPackage, true, productionUsWest1);
         assertStatus(expected, app.id(), tester.controller());
 
         expected = JobStatus.initial(productionUsEast3)
-                            .withTriggering(vespaVersion, version, Optional.ofNullable(tester.application(app.id()).deployments().get(productionUsEast3.zone(main))), "",
+                            .withTriggering(vespaVersion, version, Optional.ofNullable(tester.instance(app.id()).deployments().get(productionUsEast3.zone(main))), "",
                                             tester.clock().instant().truncatedTo(MILLIS))
                             .withCompletion(42, Optional.empty(), tester.clock().instant().truncatedTo(MILLIS));
-        tester.deployAndNotify(app, applicationPackage, true, productionUsEast3);
+        tester.deployAndNotify(app.id(), applicationPackage, true, productionUsEast3);
         assertStatus(expected, app.id(), tester.controller());
 
         // Verify deployed version
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/ControllerTester.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/ControllerTester.java
index 6744bdea985..07c24030992 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/ControllerTester.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/ControllerTester.java
@@ -126,8 +126,11 @@ public final class ControllerTester {
               .ifPresent(configureFunc);
     }
 
-    public static BuildService.BuildJob buildJob(Instance instance, JobType jobType) {
-        return BuildService.BuildJob.of(instance.id(), instance.deploymentJobs().projectId().getAsLong(), jobType.jobName());
+    public static BuildService.BuildJob buildJob(ApplicationId id, JobType jobType) {
+        if (jobType == JobType.component)
+            throw new AssertionError("Not supposed to happen");
+
+        return BuildService.BuildJob.of(id, 0, jobType.jobName());
     }
 
     public Controller controller() { return controller; }
@@ -157,27 +160,24 @@ public final class ControllerTester {
     }
 
     /** Creates the given tenant and application and deploys it */
-    public Instance createAndDeploy(String tenantName, String domainName, String applicationName, Environment environment, long projectId, Long propertyId) {
-        return createAndDeploy(tenantName, domainName, applicationName, toZone(environment), projectId, propertyId);
+    public void createAndDeploy(String tenantName, String domainName, String applicationName, Environment environment, long projectId, Long propertyId) {
+        createAndDeploy(tenantName, domainName, applicationName, toZone(environment), projectId, propertyId);
     }
 
     /** Creates the given tenant and application and deploys it */
-    public Instance createAndDeploy(String tenantName, String domainName, String applicationName,
+    public void createAndDeploy(String tenantName, String domainName, String applicationName,
                                     String instanceName, ZoneId zone, long projectId, Long propertyId) {
-        TenantName tenant = createTenant(tenantName, domainName, propertyId);
-        Instance instance = createApplication(tenant, applicationName, instanceName, projectId);
-        deploy(instance, zone);
-        return instance;
+        throw new AssertionError("Not supposed to use this");
     }
 
     /** Creates the given tenant and application and deploys it */
-    public Instance createAndDeploy(String tenantName, String domainName, String applicationName, ZoneId zone, long projectId, Long propertyId) {
-        return createAndDeploy(tenantName, domainName, applicationName, "default", zone, projectId, propertyId);
+    public void createAndDeploy(String tenantName, String domainName, String applicationName, ZoneId zone, long projectId, Long propertyId) {
+        createAndDeploy(tenantName, domainName, applicationName, "default", zone, projectId, propertyId);
     }
 
     /** Creates the given tenant and application and deploys it */
-    public Instance createAndDeploy(String tenantName, String domainName, String applicationName, Environment environment, long projectId) {
-        return createAndDeploy(tenantName, domainName, applicationName, environment, projectId, null);
+    public void createAndDeploy(String tenantName, String domainName, String applicationName, Environment environment, long projectId) {
+        createAndDeploy(tenantName, domainName, applicationName, environment, projectId, null);
     }
 
     /** Create application from slime */
@@ -241,32 +241,32 @@ public final class ControllerTester {
                                                                 new OktaAccessToken("okta-token")));
     }
 
-    public Instance createApplication(TenantName tenant, String applicationName, String instanceName, long projectId) {
+    public Application createApplication(TenantName tenant, String applicationName, String instanceName, long projectId) {
         ApplicationId applicationId = ApplicationId.from(tenant.value(), applicationName, instanceName);
         controller().applications().createApplication(applicationId, credentialsFor(applicationId));
-        controller().applications().lockOrThrow(applicationId, lockedInstance ->
-                controller().applications().store(lockedInstance.withProjectId(OptionalLong.of(projectId))));
-        return controller().applications().require(applicationId);
+        controller().applications().lockApplicationOrThrow(applicationId, application ->
+                controller().applications().store(application.withProjectId(OptionalLong.of(projectId))));
+        return controller().applications().requireApplication(applicationId);
     }
 
-    public void deploy(Instance instance, ZoneId zone) {
-        deploy(instance, zone, new ApplicationPackage(new byte[0]));
+    public void deploy(ApplicationId id, ZoneId zone) {
+        deploy(id, zone, new ApplicationPackage(new byte[0]));
     }
 
-    public void deploy(Instance instance, ZoneId zone, ApplicationPackage applicationPackage) {
-        deploy(instance, zone, applicationPackage, false);
+    public void deploy(ApplicationId id, ZoneId zone, ApplicationPackage applicationPackage) {
+        deploy(id, zone, applicationPackage, false);
     }
 
-    public void deploy(Instance instance, ZoneId zone, ApplicationPackage applicationPackage, boolean deployCurrentVersion) {
-        deploy(instance, zone, Optional.of(applicationPackage), deployCurrentVersion);
+    public void deploy(ApplicationId id, ZoneId zone, ApplicationPackage applicationPackage, boolean deployCurrentVersion) {
+        deploy(id, zone, Optional.of(applicationPackage), deployCurrentVersion);
     }
 
-    public void deploy(Instance instance, ZoneId zone, Optional<ApplicationPackage> applicationPackage, boolean deployCurrentVersion) {
-        deploy(instance, zone, applicationPackage, deployCurrentVersion, Optional.empty());
+    public void deploy(ApplicationId id, ZoneId zone, Optional<ApplicationPackage> applicationPackage, boolean deployCurrentVersion) {
+        deploy(id, zone, applicationPackage, deployCurrentVersion, Optional.empty());
     }
 
-    public void deploy(Instance instance, ZoneId zone, Optional<ApplicationPackage> applicationPackage, boolean deployCurrentVersion, Optional<Version> version) {
-        controller().applications().deploy(instance.id(),
+    public void deploy(ApplicationId id, ZoneId zone, Optional<ApplicationPackage> applicationPackage, boolean deployCurrentVersion, Optional<Version> version) {
+        controller().applications().deploy(id,
                                            zone,
                                            applicationPackage,
                                            new DeployOptions(false, version, false, deployCurrentVersion));
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/BuildJob.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/BuildJob.java
index 7b2aba296a4..afe4a1dba1f 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/BuildJob.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/BuildJob.java
@@ -2,7 +2,7 @@
 package com.yahoo.vespa.hosted.controller.deployment;
 
 import com.yahoo.config.provision.ApplicationId;
-import com.yahoo.vespa.hosted.controller.Instance;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.api.integration.deployment.ApplicationVersion;
 import com.yahoo.vespa.hosted.controller.api.integration.deployment.JobType;
 import com.yahoo.vespa.hosted.controller.api.integration.deployment.SourceRevision;
@@ -51,10 +51,10 @@ public class BuildJob {
         return this;
     }
 
-    public BuildJob application(Instance instance) {
-        this.applicationId = instance.id();
-        if (instance.deploymentJobs().projectId().isPresent()) {
-            this.projectId = instance.deploymentJobs().projectId().getAsLong();
+    public BuildJob application(Application application) {
+        this.applicationId = application.id();
+        if (application.deploymentJobs().projectId().isPresent()) {
+            this.projectId = application.deploymentJobs().projectId().getAsLong();
         }
         return this;
     }
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/DeploymentTester.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/DeploymentTester.java
index 02b45b77769..c1d8c32f516 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/DeploymentTester.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/DeploymentTester.java
@@ -7,6 +7,7 @@ import com.yahoo.config.provision.Environment;
 import com.yahoo.config.provision.TenantName;
 import com.yahoo.config.provision.zone.ZoneApi;
 import com.yahoo.test.ManualClock;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Instance;
 import com.yahoo.vespa.hosted.controller.ApplicationController;
 import com.yahoo.vespa.hosted.controller.Controller;
@@ -112,11 +113,15 @@ public class DeploymentTester {
 
     public ConfigServerMock configServer() { return tester.serviceRegistry().configServerMock(); }
 
-    public Instance application(String name) {
-        return application(ApplicationId.from("tenant1", name, "default"));
+    public Application application(ApplicationId id) {
+        return controller().applications().requireApplication(id);
     }
 
-    public Instance application(ApplicationId application) {
+    public Instance instance(String name) {
+        return instance(ApplicationId.from("tenant1", name, "default"));
+    }
+
+    public Instance instance(ApplicationId application) {
         return controller().applications().require(application);
     }
 
@@ -169,11 +174,11 @@ public class DeploymentTester {
         return configServer().initialVersion();
     }
 
-    public Instance createApplication(String applicationName, String tenantName, long projectId, long propertyId) {
+    public Application createApplication(String applicationName, String tenantName, long projectId, long propertyId) {
         return createApplication("default", applicationName, tenantName, projectId, propertyId);
     }
 
-    public Instance createApplication(String instanceName, String applicationName, String tenantName, long projectId, long propertyId) {
+    public Application createApplication(String instanceName, String applicationName, String tenantName, long projectId, long propertyId) {
         TenantName tenant = tester.createTenant(tenantName, UUID.randomUUID().toString(), propertyId);
         return tester.createApplication(tenant, applicationName, instanceName, projectId);
     }
@@ -191,130 +196,134 @@ public class DeploymentTester {
     }
 
     /** Simulate the full lifecycle of an application deployment as declared in given application package */
-    public Instance createAndDeploy(String applicationName, int projectId, ApplicationPackage applicationPackage) {
+    public Application createAndDeploy(String applicationName, int projectId, ApplicationPackage applicationPackage) {
         TenantName tenant = tester.createTenant("tenant1", "domain1", 1L);
         return createAndDeploy(tenant, applicationName, projectId, applicationPackage);
     }
 
     /** Simulate the full lifecycle of an application deployment as declared in given application package */
-    public Instance createAndDeploy(TenantName tenant, String applicationName, int projectId, ApplicationPackage applicationPackage) {
-        Instance instance = tester.createApplication(tenant, applicationName, "default", projectId);
-        deployCompletely(instance, applicationPackage);
-        return applications().require(instance.id());
+    public Application createAndDeploy(TenantName tenant, String applicationName, int projectId, ApplicationPackage applicationPackage) {
+        Application application = tester.createApplication(tenant, applicationName, "default", projectId);
+        deployCompletely(application, applicationPackage);
+        return applications().requireApplication(application.id());
     }
 
     /** Simulate the full lifecycle of an application deployment to prod.us-west-1 with the given upgrade policy */
-    public Instance createAndDeploy(String applicationName, int projectId, String upgradePolicy) {
+    public Application createAndDeploy(String applicationName, int projectId, String upgradePolicy) {
         return createAndDeploy(applicationName, projectId, applicationPackage(upgradePolicy));
     }
 
     /** Simulate the full lifecycle of an application deployment to prod.us-west-1 with the given upgrade policy */
-    public Instance createAndDeploy(TenantName tenant, String applicationName, int projectId, String upgradePolicy) {
-        return createAndDeploy(tenant, applicationName, projectId, applicationPackage(upgradePolicy));
+    public void createAndDeploy(TenantName tenant, String applicationName, int projectId, String upgradePolicy) {
+        createAndDeploy(tenant, applicationName, projectId, applicationPackage(upgradePolicy));
     }
 
     /** Deploy application completely using the given application package */
-    public void deployCompletely(Instance instance, ApplicationPackage applicationPackage) {
-        deployCompletely(instance, applicationPackage, BuildJob.defaultBuildNumber);
+    public void deployCompletely(Application application, ApplicationPackage applicationPackage) {
+        deployCompletely(application, applicationPackage, BuildJob.defaultBuildNumber);
     }
 
-    public void completeDeploymentWithError(Instance instance, ApplicationPackage applicationPackage, long buildNumber, JobType failOnJob) {
-        jobCompletion(JobType.component).application(instance)
+    public void completeDeploymentWithError(Application application, ApplicationPackage applicationPackage, long buildNumber, JobType failOnJob) {
+        jobCompletion(JobType.component).application(application)
                                         .buildNumber(buildNumber)
                                         .uploadArtifact(applicationPackage)
                                         .submit();
-        completeDeployment(instance, applicationPackage, Optional.ofNullable(failOnJob));
+        completeDeployment(application, applicationPackage, Optional.ofNullable(failOnJob));
     }
 
-    public void deployCompletely(Instance instance, ApplicationPackage applicationPackage, long buildNumber) {
-        completeDeploymentWithError(instance, applicationPackage, buildNumber, null);
+    public void deployCompletely(Application application, ApplicationPackage applicationPackage, long buildNumber) {
+        completeDeploymentWithError(application, applicationPackage, buildNumber, null);
     }
 
-    private void completeDeployment(Instance instance, ApplicationPackage applicationPackage, Optional<JobType> failOnJob) {
-        assertTrue(instance.id() + " has pending changes to deploy", applications().require(instance.id()).change().hasTargets());
+    private void completeDeployment(Application application, ApplicationPackage applicationPackage, Optional<JobType> failOnJob) {
+        assertTrue(application.id() + " has pending changes to deploy", applications().require(application.id()).change().hasTargets());
         DeploymentSteps steps = controller().applications().deploymentTrigger().steps(applicationPackage.deploymentSpec());
         List<JobType> jobs = steps.jobs();
+        // TODO jonmv: Change to list instances here.
         for (JobType job : jobs) {
             boolean failJob = failOnJob.map(j -> j.equals(job)).orElse(false);
-            deployAndNotify(instance, applicationPackage, ! failJob, job);
+            deployAndNotify(application.id(), applicationPackage, ! failJob, job);
             if (failJob) {
                 break;
             }
         }
         if (failOnJob.isPresent()) {
-            assertTrue(applications().require(instance.id()).change().hasTargets());
-            assertTrue(applications().require(instance.id()).deploymentJobs().hasFailures());
+            assertTrue(applications().require(application.id()).change().hasTargets());
+            assertTrue(applications().require(application.id()).deploymentJobs().hasFailures());
         } else {
-            assertFalse(applications().require(instance.id()).change().hasTargets());
+            assertFalse(applications().require(application.id()).change().hasTargets());
         }
         if (updateDnsAutomatically) {
             flushDnsRequests();
         }
     }
 
-    public void completeUpgrade(Instance instance, Version version, String upgradePolicy) {
-        completeUpgrade(instance, version, applicationPackage(upgradePolicy));
+    public void completeUpgrade(Application application, Version version, String upgradePolicy) {
+        completeUpgrade(application, version, applicationPackage(upgradePolicy));
     }
 
-    public void completeUpgrade(Instance instance, Version version, ApplicationPackage applicationPackage) {
-        assertTrue(instance + " has a change", applications().require(instance.id()).change().hasTargets());
-        assertEquals(Change.of(version), applications().require(instance.id()).change());
-        completeDeployment(instance, applicationPackage, Optional.empty());
+    public void completeUpgrade(Application application, Version version, ApplicationPackage applicationPackage) {
+        assertTrue(application + " has a change", applications().require(application.id()).change().hasTargets());
+        assertEquals(Change.of(version), applications().require(application.id()).change());
+        completeDeployment(application, applicationPackage, Optional.empty());
     }
 
-    public void completeUpgradeWithError(Instance instance, Version version, String upgradePolicy, JobType failOnJob) {
-        completeUpgradeWithError(instance, version, applicationPackage(upgradePolicy), Optional.of(failOnJob));
+    public void completeUpgradeWithError(Application application, Version version, String upgradePolicy, JobType failOnJob) {
+        completeUpgradeWithError(application, version, applicationPackage(upgradePolicy), Optional.of(failOnJob));
     }
 
-    public void completeUpgradeWithError(Instance instance, Version version, ApplicationPackage applicationPackage, JobType failOnJob) {
-        completeUpgradeWithError(instance, version, applicationPackage, Optional.of(failOnJob));
+    public void completeUpgradeWithError(Application application, Version version, ApplicationPackage applicationPackage, JobType failOnJob) {
+        completeUpgradeWithError(application, version, applicationPackage, Optional.of(failOnJob));
     }
 
-    private void completeUpgradeWithError(Instance instance, Version version, ApplicationPackage applicationPackage, Optional<JobType> failOnJob) {
-        assertTrue(applications().require(instance.id()).change().hasTargets());
-        assertEquals(Change.of(version), applications().require(instance.id()).change());
-        completeDeployment(instance, applicationPackage, failOnJob);
+    private void completeUpgradeWithError(Application application, Version version, ApplicationPackage applicationPackage, Optional<JobType> failOnJob) {
+        assertTrue(applications().require(application.id()).change().hasTargets());
+        assertEquals(Change.of(version), applications().require(application.id()).change());
+        completeDeployment(application, applicationPackage, failOnJob);
     }
 
-    public void deploy(JobType job, Instance instance, ApplicationPackage applicationPackage) {
-        deploy(job, instance, Optional.of(applicationPackage), false);
+    public void deploy(JobType job, ApplicationId id, ApplicationPackage applicationPackage) {
+        deploy(job, id, Optional.of(applicationPackage), false);
     }
 
-    public void deploy(JobType job, Instance instance, ApplicationPackage applicationPackage,
+    public void deploy(JobType job, ApplicationId id, ApplicationPackage applicationPackage,
                        boolean deployCurrentVersion) {
-        deploy(job, instance, Optional.of(applicationPackage), deployCurrentVersion);
+        deploy(job, id, Optional.of(applicationPackage), deployCurrentVersion);
     }
 
-    public void deploy(JobType job, Instance instance, Optional<ApplicationPackage> applicationPackage,
+    public void deploy(JobType job, ApplicationId id, Optional<ApplicationPackage> applicationPackage,
                        boolean deployCurrentVersion) {
-        tester.deploy(instance, job.zone(controller().system()), applicationPackage, deployCurrentVersion);
+        tester.deploy(id, job.zone(controller().system()), applicationPackage, deployCurrentVersion);
     }
 
-    public void deployAndNotify(Instance instance, String upgradePolicy, boolean success, JobType job) {
-        deployAndNotify(instance, applicationPackage(upgradePolicy), success, job);
+    public void deployAndNotify(Instance i, String upgradePolicy, boolean success, JobType job) {
+        deployAndNotify(i.id(), applicationPackage(upgradePolicy), success, job);
     }
 
-    public void deployAndNotify(Instance instance, ApplicationPackage applicationPackage, boolean success, JobType job) {
-        deployAndNotify(instance, Optional.of(applicationPackage), success, job);
+    public void deployAndNotify(ApplicationId id, ApplicationPackage applicationPackage, boolean success, JobType job) {
+        deployAndNotify(id, Optional.of(applicationPackage), success, job);
     }
 
-    public void deployAndNotify(Instance instance, boolean success, JobType job) {
-        deployAndNotify(instance, Optional.empty(), success, job);
+    public void deployAndNotify(Instance i, boolean success, JobType job) {
+        deployAndNotify(i.id(), Optional.empty(), success, job);
+    }
+    public void deployAndNotify(ApplicationId id, boolean success, JobType job) {
+        deployAndNotify(id, Optional.empty(), success, job);
     }
 
-    public void deployAndNotify(Instance instance, Optional<ApplicationPackage> applicationPackage, boolean success, JobType job) {
+    public void deployAndNotify(ApplicationId id, Optional<ApplicationPackage> applicationPackage, boolean success, JobType job) {
         if (success) {
             // Staging deploys twice, once with current version and once with new version
             if (job == JobType.stagingTest) {
-                deploy(job, instance, applicationPackage, true);
+                deploy(job, id, applicationPackage, true);
             }
-            deploy(job, instance, applicationPackage, false);
+            deploy(job, id, applicationPackage, false);
         }
         // Deactivate test deployments after deploy. This replicates the behaviour of the tenant pipeline
         if (job.isTest()) {
-            controller().applications().deactivate(instance.id(), job.zone(controller().system()));
+            controller().applications().deactivate(id, job.zone(controller().system()));
         }
-        jobCompletion(job).application(instance).success(success).submit();
+        jobCompletion(job).application(id).success(success).submit();
     }
 
     public Optional<JobStatus.JobRun> firstFailing(Instance instance, JobType job) {
@@ -350,7 +359,7 @@ public class DeploymentTester {
     }
 
     private boolean isRunning(JobType job, ApplicationId application) {
-        return buildService().jobs().contains(ControllerTester.buildJob(application(application), job));
+        return buildService().jobs().contains(ControllerTester.buildJob(instance(application).id(), job));
     }
 
 }
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/DeploymentTriggerTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/DeploymentTriggerTest.java
index 7cb520f0fd9..389c1112dad 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/DeploymentTriggerTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/DeploymentTriggerTest.java
@@ -7,8 +7,8 @@ import com.yahoo.config.provision.TenantName;
 import com.yahoo.config.provision.zone.ZoneId;
 import com.yahoo.slime.Slime;
 import com.yahoo.vespa.config.SlimeUtils;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Instance;
-import com.yahoo.vespa.hosted.controller.ControllerTester;
 import com.yahoo.vespa.hosted.controller.api.identifiers.DeploymentId;
 import com.yahoo.vespa.hosted.controller.api.integration.BuildService;
 import com.yahoo.vespa.hosted.controller.api.integration.deployment.ApplicationVersion;
@@ -68,7 +68,8 @@ public class DeploymentTriggerTest {
 
     @Test
     public void testTriggerFailing() {
-        Instance app = tester.createApplication("app1", "tenant1", 1, 1L);
+        Application app = tester.createApplication("app1", "tenant1", 1, 1L);
+        Instance instance = tester.instance(app.id());
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .upgradePolicy("default")
                 .environment(Environment.prod)
@@ -80,37 +81,39 @@ public class DeploymentTriggerTest {
 
         // Deploy completely once
         tester.jobCompletion(component).application(app).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, JobType.stagingTest);
-        tester.deployAndNotify(app, applicationPackage, true, JobType.productionUsWest1);
+        tester.deployAndNotify(instance.id(), applicationPackage, true, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), applicationPackage, true, JobType.stagingTest);
+        tester.deployAndNotify(instance.id(), applicationPackage, true, JobType.productionUsWest1);
 
         // New version is released
         version = Version.fromString("6.3");
         tester.upgradeSystem(version);
 
         // staging-test times out and is retried
-        tester.buildService().remove(buildJob(app, stagingTest));
+        tester.buildService().remove(buildJob(app.id(), stagingTest));
         tester.readyJobTrigger().maintain();
         assertEquals("Retried dead job", 2, tester.buildService().jobs().size());
         tester.assertRunning(stagingTest, app.id());
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
 
         // system-test is now the only running job -- production jobs haven't started yet, since it is unfinished.
         tester.assertRunning(systemTest, app.id());
         assertEquals(1, tester.buildService().jobs().size());
 
         // system-test fails and is retried
-        tester.deployAndNotify(app, applicationPackage, false, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, JobType.systemTest);
         assertEquals("Job is retried on failure", 1, tester.buildService().jobs().size());
-        tester.deployAndNotify(app, applicationPackage, true, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.systemTest);
 
         tester.assertRunning(productionUsWest1, app.id());
     }
 
     @Test
     public void testIndependentInstances() {
-        Instance instance1 = tester.createApplication("instance1", "app", "tenant", 1, 1L);
-        Instance instance2 = tester.createApplication("instance2", "app", "tenant", 2, 1L);
+        Application app1 = tester.createApplication("instance1", "app", "tenant", 1, 1L);
+        Application app2 = tester.createApplication("instance2", "app", "tenant", 2, 1L);
+        Instance instance1 = tester.instance(app1.id());
+        Instance instance2 = tester.instance(app2.id());
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                                                         .upgradePolicy("default")
                                                         .environment(Environment.prod)
@@ -121,27 +124,27 @@ public class DeploymentTriggerTest {
         tester.upgradeSystem(version);
 
         // Deploy completely once
-        tester.jobCompletion(component).application(instance1).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(instance1, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(instance1, applicationPackage, true, JobType.stagingTest);
-        tester.deployAndNotify(instance1, applicationPackage, true, JobType.productionUsWest1);
+        tester.jobCompletion(component).application(app1).uploadArtifact(applicationPackage).submit();
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, JobType.productionUsWest1);
 
-        tester.jobCompletion(component).application(instance2).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(instance2, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(instance2, applicationPackage, true, JobType.stagingTest);
-        tester.deployAndNotify(instance2, applicationPackage, true, JobType.productionUsWest1);
+        tester.jobCompletion(component).application(app2).uploadArtifact(applicationPackage).submit();
+        tester.deployAndNotify(instance2.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance2.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
+        tester.deployAndNotify(instance2.id(), Optional.of(applicationPackage), true, JobType.productionUsWest1);
 
         // New version is released
         Version newVersion = Version.fromString("6.3");
         tester.upgradeSystem(newVersion);
 
         // instance1 upgrades, but not instance 2
-        tester.deployAndNotify(instance1, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(instance1, applicationPackage, true, JobType.stagingTest);
-        tester.deployAndNotify(instance1, applicationPackage, true, JobType.productionUsWest1);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, JobType.productionUsWest1);
 
-        Version instance1Version = tester.application(instance1.id()).deployments().get(JobType.productionUsWest1.zone(main)).version();
-        Version instance2Version = tester.application(instance2.id()).deployments().get(JobType.productionUsWest1.zone(main)).version();
+        Version instance1Version = tester.instance(app1.id()).deployments().get(JobType.productionUsWest1.zone(main)).version();
+        Version instance2Version = tester.instance(app2.id()).deployments().get(JobType.productionUsWest1.zone(main)).version();
 
         assertEquals(newVersion, instance1Version);
         assertEquals(version, instance2Version);
@@ -152,26 +155,27 @@ public class DeploymentTriggerTest {
         InternalDeploymentTester iTester = new InternalDeploymentTester();
         DeploymentTester tester = iTester.tester();
 
-        Instance app = iTester.app();
+        Instance instance = iTester.instance();
+        Application application = tester.application(instance.id());
         ApplicationPackage applicationPackage = InternalDeploymentTester.applicationPackage;
 
-        tester.jobCompletion(component).application(app).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app, true, systemTest);
-        tester.deployAndNotify(app, true, stagingTest);
-        tester.assertRunning(productionUsCentral1, app.id());
+        tester.jobCompletion(component).application(application).uploadArtifact(applicationPackage).submit();
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
+        tester.assertRunning(productionUsCentral1, instance.id());
 
         // Jobs run externally are not affected.
-        tester.jobCompletion(component).application(app).nextBuildNumber().uploadArtifact(applicationPackage).submit();
-        tester.assertRunning(productionUsCentral1, app.id());
-
-        tester.applications().deploymentTrigger().cancelChange(app.id(), ALL);
-        tester.deployAndNotify(app, false, systemTest);
-        tester.deployAndNotify(app, false, stagingTest);
-        tester.deployAndNotify(app, false, productionUsCentral1);
-        assertEquals(Change.empty(), tester.application(app.id()).change());
-        tester.assertNotRunning(systemTest, app.id());
-        tester.assertNotRunning(stagingTest, app.id());
-        tester.assertNotRunning(productionUsCentral1, app.id());
+        tester.jobCompletion(component).application(application).nextBuildNumber().uploadArtifact(applicationPackage).submit();
+        tester.assertRunning(productionUsCentral1, instance.id());
+
+        tester.applications().deploymentTrigger().cancelChange(instance.id(), ALL);
+        tester.deployAndNotify(instance.id(), Optional.empty(), false, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), false, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), false, productionUsCentral1);
+        assertEquals(Change.empty(), tester.instance(instance.id()).change());
+        tester.assertNotRunning(systemTest, instance.id());
+        tester.assertNotRunning(stagingTest, instance.id());
+        tester.assertNotRunning(productionUsCentral1, instance.id());
 
         RunId id = iTester.newRun(productionUsCentral1);
         assertTrue(iTester.jobs().active(id).isPresent());
@@ -194,7 +198,7 @@ public class DeploymentTriggerTest {
         tester.readyJobTrigger().maintain();
         iTester.runJob(JobType.productionUsWest1);
         iTester.runJob(JobType.productionUsEast3);
-        assertEquals(Change.empty(), iTester.app().change());
+        assertEquals(Change.empty(), iTester.instance().change());
 
         tester.upgradeSystem(new Version("8.9"));
         iTester.runJob(JobType.systemTest);
@@ -213,7 +217,8 @@ public class DeploymentTriggerTest {
     public void deploymentSpecDecidesTriggerOrder() {
         TenantName tenant = tester.controllerTester().createTenant("tenant1", "domain1", 1L);
         MockBuildService mockBuildService = tester.buildService();
-        Instance instance = tester.controllerTester().createApplication(tenant, "app1", "default", 1L);
+        Application application = tester.controllerTester().createApplication(tenant, "app1", "default", 1L);
+        Instance instance = tester.instance(application.id());
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-east-3")
@@ -222,21 +227,22 @@ public class DeploymentTriggerTest {
                 .build();
 
         // Component job finishes
-        tester.jobCompletion(component).application(instance).uploadArtifact(applicationPackage).submit();
+        tester.jobCompletion(component).application(application).uploadArtifact(applicationPackage).submit();
 
         // Application is deployed to all test environments and declared zones
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.stagingTest);
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.productionUsEast3);
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.productionUsCentral1);
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsWest1);
         assertTrue("All jobs consumed", mockBuildService.jobs().isEmpty());
     }
 
     @Test
     public void deploymentsSpecWithDelays() {
         MockBuildService mockBuildService = tester.buildService();
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
+        Application application = tester.createApplication("app1", "tenant1", 1, 1L);
+        Instance instance = tester.instance(application.id());
 
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
@@ -249,11 +255,11 @@ public class DeploymentTriggerTest {
                 .build();
 
         // Component job finishes
-        tester.jobCompletion(component).application(instance).uploadArtifact(applicationPackage).submit();
+        tester.jobCompletion(component).application(application).uploadArtifact(applicationPackage).submit();
 
         // Test jobs pass
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
         tester.deploymentTrigger().triggerReadyJobs();
 
         // No jobs have started yet, as 30 seconds have not yet passed.
@@ -263,16 +269,16 @@ public class DeploymentTriggerTest {
 
         // 30 seconds later, the first jobs may trigger.
         assertEquals(1, mockBuildService.jobs().size());
-        tester.assertRunning(productionUsWest1, instance.id());
+        tester.assertRunning(productionUsWest1, application.id());
 
         // 3 minutes pass, delayed trigger does nothing as us-west-1 is still in progress
         tester.clock().advance(Duration.ofMinutes(3));
         tester.deploymentTrigger().triggerReadyJobs();
         assertEquals(1, mockBuildService.jobs().size());
-        tester.assertRunning(productionUsWest1, instance.id());
+        tester.assertRunning(productionUsWest1, application.id());
 
         // us-west-1 completes
-        tester.deployAndNotify(instance, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsWest1);
 
         // Delayed trigger does nothing as not enough time has passed after us-west-1 completion
         tester.deploymentTrigger().triggerReadyJobs();
@@ -286,7 +292,7 @@ public class DeploymentTriggerTest {
         // 4 minutes pass, us-central-1 is triggered
         tester.clock().advance(Duration.ofMinutes(1));
         tester.deploymentTrigger().triggerReadyJobs();
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsCentral1);
         assertTrue("All jobs consumed", mockBuildService.jobs().isEmpty());
 
         // Delayed trigger job runs again, with nothing to trigger
@@ -297,7 +303,8 @@ public class DeploymentTriggerTest {
 
     @Test
     public void deploymentSpecWithParallelDeployments() {
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
+        Application application = tester.createApplication("app1", "tenant1", 1, 1L);
+        Instance instance = tester.instance(application.id());
 
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
@@ -307,75 +314,76 @@ public class DeploymentTriggerTest {
                 .build();
 
         // Component job finishes
-        tester.jobCompletion(component).application(instance).uploadArtifact(applicationPackage).submit();
+        tester.jobCompletion(component).application(application).uploadArtifact(applicationPackage).submit();
 
         // Test jobs pass
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
 
         // Deploys in first region
         assertEquals(1, tester.buildService().jobs().size());
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsCentral1);
 
         // Deploys in two regions in parallel
         assertEquals(2, tester.buildService().jobs().size());
-        tester.assertRunning(productionUsEast3, instance.id());
-        tester.assertRunning(productionUsWest1, instance.id());
+        tester.assertRunning(productionUsEast3, application.id());
+        tester.assertRunning(productionUsWest1, application.id());
 
-        tester.deploy(JobType.productionUsWest1, instance, applicationPackage, false);
-        tester.jobCompletion(JobType.productionUsWest1).application(instance).submit();
+        tester.deploy(JobType.productionUsWest1, instance.id(), applicationPackage, false);
+        tester.jobCompletion(JobType.productionUsWest1).application(application).submit();
         assertEquals("One job still running.", JobType.productionUsEast3.jobName(), tester.buildService().jobs().get(0).jobName());
 
-        tester.deploy(JobType.productionUsEast3, instance, applicationPackage, false);
-        tester.jobCompletion(JobType.productionUsEast3).application(instance).submit();
+        tester.deploy(JobType.productionUsEast3, instance.id(), applicationPackage, false);
+        tester.jobCompletion(JobType.productionUsEast3).application(application).submit();
 
         // Last region completes
         assertEquals(1, tester.buildService().jobs().size());
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.productionEuWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionEuWest1);
         assertTrue("All jobs consumed", tester.buildService().jobs().isEmpty());
     }
 
     @Test
     public void testNoOtherChangesDuringSuspension() {
         // Application is deployed in 3 regions:
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
+        Application application = tester.createApplication("app1", "tenant1", 1, 1L);
+        Instance instance = tester.instance(application.id());
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                                                         .environment(Environment.prod)
                                                         .region("us-central-1")
                                                         .parallel("us-west-1", "us-east-3")
                                                         .build();
         tester.jobCompletion(component)
-              .application(instance)
+              .application(application)
               .uploadArtifact(applicationPackage)
               .submit();
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.stagingTest);
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.productionUsCentral1);
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.productionUsWest1);
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsEast3);
 
         // The first production zone is suspended:
-        tester.configServer().setSuspended(new DeploymentId(instance.id(), JobType.productionUsCentral1.zone(tester.controller().system())), true);
+        tester.configServer().setSuspended(new DeploymentId(application.id(), JobType.productionUsCentral1.zone(tester.controller().system())), true);
 
         // A new change needs to be pushed out, but should not go beyond the suspended zone:
         tester.jobCompletion(component)
-              .application(instance)
+              .application(application)
               .nextBuildNumber()
               .sourceRevision(new SourceRevision("repository1", "master", "cafed00d"))
               .uploadArtifact(applicationPackage)
               .submit();
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.stagingTest);
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsCentral1);
         tester.triggerUntilQuiescence();
-        tester.assertNotRunning(JobType.productionUsEast3, instance.id());
-        tester.assertNotRunning(JobType.productionUsWest1, instance.id());
+        tester.assertNotRunning(JobType.productionUsEast3, application.id());
+        tester.assertNotRunning(JobType.productionUsWest1, application.id());
 
         // The zone is unsuspended so jobs start:
-        tester.configServer().setSuspended(new DeploymentId(instance.id(), JobType.productionUsCentral1.zone(tester.controller().system())), false);
+        tester.configServer().setSuspended(new DeploymentId(application.id(), JobType.productionUsCentral1.zone(tester.controller().system())), false);
         tester.triggerUntilQuiescence();
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.productionUsWest1);
-        tester.deployAndNotify(instance, applicationPackage, true, JobType.productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsEast3);
     }
 
     @Test
@@ -385,21 +393,22 @@ public class DeploymentTriggerTest {
                 .parallel("us-east-3", "us-west-1")
                 .build();
 
-        Instance app = tester.createApplication("app1", "tenant1", 1, 11L);
+        Application app = tester.createApplication("app1", "tenant1", 1, 11L);
+        Instance instance = tester.instance(app.id());
         tester.jobCompletion(component).application(app).uploadArtifact(applicationPackage).submit();
 
         // Test environments pass
-        tester.deployAndNotify(app, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, JobType.stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
 
         // Last declared job completes first
-        tester.deploy(JobType.productionUsWest1, app, applicationPackage);
+        tester.deploy(JobType.productionUsWest1, instance.id(), applicationPackage);
         tester.jobCompletion(JobType.productionUsWest1).application(app).submit();
         assertTrue("Change is present as not all jobs are complete",
                    tester.applications().require(app.id()).change().hasTargets());
 
         // All jobs complete
-        tester.deploy(JobType.productionUsEast3, app, applicationPackage);
+        tester.deploy(JobType.productionUsEast3, instance.id(), applicationPackage);
         tester.jobCompletion(JobType.productionUsEast3).application(app).submit();
         assertFalse("Change has been deployed",
                     tester.applications().require(app.id()).change().hasTargets());
@@ -409,7 +418,8 @@ public class DeploymentTriggerTest {
     public void testSuccessfulDeploymentApplicationPackageChanged() {
         TenantName tenant = tester.controllerTester().createTenant("tenant1", "domain1", 1L);
         MockBuildService mockBuildService = tester.buildService();
-        Instance instance = tester.controllerTester().createApplication(tenant, "app1", "default", 1L);
+        Application application = tester.controllerTester().createApplication(tenant, "app1", "default", 1L);
+        Instance instance = tester.instance(application.id());
         ApplicationPackage previousApplicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-east-3")
@@ -425,16 +435,16 @@ public class DeploymentTriggerTest {
                 .build();
 
         // Component job finishes
-        tester.jobCompletion(component).application(instance).uploadArtifact(newApplicationPackage).submit();
+        tester.jobCompletion(component).application(application).uploadArtifact(newApplicationPackage).submit();
 
         // Application is deployed to all test environments and declared zones
-        tester.deployAndNotify(instance, newApplicationPackage, true, JobType.systemTest);
-        tester.deploy(JobType.stagingTest, instance, previousApplicationPackage, true);
-        tester.deployAndNotify(instance, newApplicationPackage, true, JobType.stagingTest);
-        tester.deployAndNotify(instance, newApplicationPackage, true, JobType.productionUsEast3);
-        tester.deployAndNotify(instance, newApplicationPackage, true, JobType.productionUsCentral1);
-        tester.deployAndNotify(instance, newApplicationPackage, true, JobType.productionUsWest1);
-        tester.deployAndNotify(instance, newApplicationPackage, true, JobType.productionEuWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(newApplicationPackage), true, JobType.systemTest);
+        tester.deploy(JobType.stagingTest, instance.id(), previousApplicationPackage, true);
+        tester.deployAndNotify(instance.id(), Optional.of(newApplicationPackage), true, JobType.stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(newApplicationPackage), true, JobType.productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(newApplicationPackage), true, JobType.productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.of(newApplicationPackage), true, JobType.productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(newApplicationPackage), true, JobType.productionEuWest1);
         assertTrue("All jobs consumed", mockBuildService.jobs().isEmpty());
     }
 
@@ -457,7 +467,8 @@ public class DeploymentTriggerTest {
                 .region("us-central-1")
                 .region("us-east-3");
 
-        Instance app = tester.createAndDeploy("app1", 1, applicationPackageBuilder.build());
+        Application app = tester.createAndDeploy("app1", 1, applicationPackageBuilder.build());
+        Instance instance = tester.instance(app.id());
 
         tester.clock().advance(Duration.ofHours(1)); // --------------- Enter block window: 18:30
 
@@ -479,8 +490,8 @@ public class DeploymentTriggerTest {
               .uploadArtifact(changedApplication)
               .submit();
         assertTrue(tester.applications().require(app.id()).outstandingChange().hasTargets());
-        tester.deployAndNotify(app, changedApplication, true, systemTest);
-        tester.deployAndNotify(app, changedApplication, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(changedApplication), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(changedApplication), true, stagingTest);
 
         tester.outstandingChangeDeployer().run();
         assertTrue(tester.applications().require(app.id()).outstandingChange().hasTargets());
@@ -494,7 +505,7 @@ public class DeploymentTriggerTest {
         assertFalse(tester.applications().require(app.id()).outstandingChange().hasTargets());
 
         tester.deploymentTrigger().triggerReadyJobs(); // Schedules staging test for the blocked production job(s)
-        assertEquals(singletonList(buildJob(app, productionUsWest1)), tester.buildService().jobs());
+        assertEquals(singletonList(buildJob(app.id(), productionUsWest1)), tester.buildService().jobs());
     }
 
     @Test
@@ -506,7 +517,8 @@ public class DeploymentTriggerTest {
                 .region("us-west-1")
                 .region("us-east-3")
                 .build();
-        Instance instance = tester.createAndDeploy("app1", 1, applicationPackage);
+        Application application = tester.createAndDeploy("app1", 1, applicationPackage);
+        Instance instance = tester.instance(application.id());
 
         // Application on (6.1, 1.0.42)
         Version v1 = Version.fromString("6.1");
@@ -514,56 +526,57 @@ public class DeploymentTriggerTest {
         // Application is mid-upgrade when block window begins, and has an outstanding change.
         Version v2 = Version.fromString("6.2");
         tester.upgradeSystem(v2);
-        tester.jobCompletion(component).application(instance).nextBuildNumber().uploadArtifact(applicationPackage).submit();
+        tester.jobCompletion(component).application(application).nextBuildNumber().uploadArtifact(applicationPackage).submit();
 
-        tester.deployAndNotify(instance, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(instance, applicationPackage, true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
 
         // Entering block window will keep the outstanding change in place.
         tester.clock().advance(Duration.ofHours(1));
         tester.outstandingChangeDeployer().run();
-        tester.deployAndNotify(instance, applicationPackage, true, productionUsWest1);
-        assertEquals(BuildJob.defaultBuildNumber, tester.application(instance.id()).deploymentJobs().jobStatus()
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsWest1);
+        assertEquals(BuildJob.defaultBuildNumber, tester.instance(application.id()).deploymentJobs().jobStatus()
                                                         .get(productionUsWest1).lastSuccess().get().application().buildNumber().getAsLong());
-        assertEquals((BuildJob.defaultBuildNumber + 1), tester.application(instance.id()).outstandingChange().application().get().buildNumber().getAsLong());
+        assertEquals((BuildJob.defaultBuildNumber + 1), tester.instance(application.id()).outstandingChange().application().get().buildNumber().getAsLong());
 
         tester.readyJobTrigger().maintain();
         // Platform upgrade keeps rolling, since it has already deployed in a production zone, and tests for the new revision have also started.
         assertEquals(3, tester.buildService().jobs().size());
-        tester.deployAndNotify(instance, applicationPackage, true, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsEast3);
         assertEquals(2, tester.buildService().jobs().size());
 
         // Upgrade is done, and oustanding change rolls out when block window ends.
-        assertEquals(Change.empty(), tester.application(instance.id()).change());
-        assertFalse(tester.application(instance.id()).change().hasTargets());
-        assertTrue(tester.application(instance.id()).outstandingChange().hasTargets());
+        assertEquals(Change.empty(), tester.instance(application.id()).change());
+        assertFalse(tester.instance(application.id()).change().hasTargets());
+        assertTrue(tester.instance(application.id()).outstandingChange().hasTargets());
 
-        tester.deployAndNotify(instance, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(instance, applicationPackage, true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
         tester.clock().advance(Duration.ofHours(1));
         tester.outstandingChangeDeployer().run();
-        assertTrue(tester.application(instance.id()).change().hasTargets());
-        assertFalse(tester.application(instance.id()).outstandingChange().hasTargets());
+        assertTrue(tester.instance(application.id()).change().hasTargets());
+        assertFalse(tester.instance(application.id()).outstandingChange().hasTargets());
 
         tester.readyJobTrigger().run();
-        tester.deployAndNotify(instance, applicationPackage, true, productionUsWest1);
-        tester.deployAndNotify(instance, applicationPackage, true, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsEast3);
 
-        assertFalse(tester.application(instance.id()).change().hasTargets());
-        assertFalse(tester.application(instance.id()).outstandingChange().hasTargets());
+        assertFalse(tester.instance(application.id()).change().hasTargets());
+        assertFalse(tester.instance(application.id()).outstandingChange().hasTargets());
     }
 
     @Test
     public void testJobPause() {
-        Instance app = tester.createAndDeploy("app", 3, "default");
+        Application app = tester.createAndDeploy("app", 3, "default");
+        Instance instance = tester.instance(app.id());
         tester.upgradeSystem(new Version("9.8.7"));
 
         tester.applications().deploymentTrigger().pauseJob(app.id(), productionUsWest1, tester.clock().instant().plus(Duration.ofSeconds(1)));
         tester.applications().deploymentTrigger().pauseJob(app.id(), productionUsEast3, tester.clock().instant().plus(Duration.ofSeconds(3)));
 
         // us-west-1 does not trigger when paused.
-        tester.deployAndNotify(app, true, systemTest);
-        tester.deployAndNotify(app, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
         tester.assertNotRunning(productionUsWest1, app.id());
 
         // us-west-1 triggers when no longer paused, but does not retry when paused again.
@@ -571,17 +584,17 @@ public class DeploymentTriggerTest {
         tester.readyJobTrigger().run();
         tester.assertRunning(productionUsWest1, app.id());
         tester.applications().deploymentTrigger().pauseJob(app.id(), productionUsWest1, tester.clock().instant().plus(Duration.ofSeconds(1)));
-        tester.deployAndNotify(app, false, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.empty(), false, productionUsWest1);
         tester.assertNotRunning(productionUsWest1, app.id());
         tester.clock().advance(Duration.ofMillis(1000));
         tester.readyJobTrigger().run();
-        tester.deployAndNotify(app, true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionUsWest1);
 
         // us-east-3 does not automatically trigger when paused, but does when forced.
         tester.assertNotRunning(productionUsEast3, app.id());
         tester.deploymentTrigger().forceTrigger(app.id(), productionUsEast3, "mrTrigger");
         tester.assertRunning(productionUsEast3, app.id());
-        assertFalse(tester.application(app.id()).deploymentJobs().jobStatus().get(productionUsEast3).pausedUntil().isPresent());
+        assertFalse(tester.instance(app.id()).deploymentJobs().jobStatus().get(productionUsEast3).pausedUntil().isPresent());
     }
 
     @Test
@@ -589,7 +602,7 @@ public class DeploymentTriggerTest {
         ReadyJobsTrigger readyJobsTrigger = new ReadyJobsTrigger(tester.controller(),
                                                                  Duration.ofHours(1),
                                                                  new JobControl(tester.controllerTester().curator()));
-        Instance app = tester.createAndDeploy("default0", 3, "default");
+        Application app = tester.createAndDeploy("default0", 3, "default");
         // Store that we are upgrading but don't start the system-tests job
         tester.controller().applications().lockOrThrow(app.id(), locked -> {
             tester.controller().applications().store(locked.withChange(Change.of(Version.fromString("6.2"))));
@@ -602,58 +615,61 @@ public class DeploymentTriggerTest {
 
     @Test
     public void applicationVersionIsNotDowngraded() {
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
-        Supplier<Instance> app = () -> tester.application(instance.id());
+        Application application = tester.createApplication("app1", "tenant1", 1, 1L);
+        Instance instance = tester.instance(application.id());
+        Supplier<Instance> app = () -> tester.instance(application.id());
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-central-1")
                 .region("eu-west-1")
                 .build();
 
-        tester.deployCompletely(instance, applicationPackage);
+        tester.deployCompletely(application, applicationPackage);
 
         // productionUsCentral1 fails after deployment, causing a mismatch between deployed and successful state.
-        tester.completeDeploymentWithError(instance, applicationPackage, BuildJob.defaultBuildNumber + 1, productionUsCentral1);
+        tester.completeDeploymentWithError(application, applicationPackage, BuildJob.defaultBuildNumber + 1, productionUsCentral1);
 
         // deployAndNotify doesn't actually deploy if the job fails, so we need to do that manually.
-        tester.deployAndNotify(instance, false, productionUsCentral1);
-        tester.deploy(productionUsCentral1, instance, Optional.empty(), false);
+        tester.deployAndNotify(instance.id(), Optional.empty(), false, productionUsCentral1);
+        tester.deploy(productionUsCentral1, instance.id(), Optional.empty(), false);
 
         ApplicationVersion appVersion1 = ApplicationVersion.from(BuildJob.defaultSourceRevision, BuildJob.defaultBuildNumber + 1);
         assertEquals(appVersion1, app.get().deployments().get(ZoneId.from("prod.us-central-1")).applicationVersion());
 
         // Verify the application change is not removed when change is cancelled.
-        tester.deploymentTrigger().cancelChange(instance.id(), PLATFORM);
+        tester.deploymentTrigger().cancelChange(application.id(), PLATFORM);
         assertEquals(Change.of(appVersion1), app.get().change());
 
         // Now cancel the change as is done through the web API.
-        tester.deploymentTrigger().cancelChange(instance.id(), ALL);
+        tester.deploymentTrigger().cancelChange(application.id(), ALL);
         assertEquals(Change.empty(), app.get().change());
 
         // A new version is released, which should now deploy the currently deployed application version to avoid downgrades.
         Version version1 = new Version("6.2");
         tester.upgradeSystem(version1);
-        tester.jobCompletion(productionUsCentral1).application(instance).unsuccessful().submit();
-        tester.deployAndNotify(instance, true, systemTest);
-        tester.deployAndNotify(instance, true, stagingTest);
-        tester.deployAndNotify(instance, false, productionUsCentral1);
+        tester.jobCompletion(productionUsCentral1).application(application).unsuccessful().submit();
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), false, productionUsCentral1);
 
         // The last job has a different target, and the tests need to run again.
         // These may now start, since the first job has been triggered once, and thus is verified already.
-        tester.deployAndNotify(instance, true, systemTest);
-        tester.deployAndNotify(instance, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
 
         // Finally, the two production jobs complete, in order.
-        tester.deployAndNotify(instance, true, productionUsCentral1);
-        tester.deployAndNotify(instance, true, productionEuWest1);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionEuWest1);
         assertEquals(appVersion1, app.get().deployments().get(ZoneId.from("prod.us-central-1")).applicationVersion());
     }
 
     @Test
     public void stepIsCompletePreciselyWhenItShouldBe() {
-        Instance instance1 = tester.createApplication("app1", "tenant1", 1, 1L);
-        Instance instance2 = tester.createApplication("app2", "tenant2", 2, 2L);
-        Supplier<Instance> app1 = () -> tester.application(instance1.id());
+        Application application1 = tester.createApplication("app1", "tenant1", 1, 1L);
+        Application application2 = tester.createApplication("app2", "tenant2", 2, 2L);
+        Instance instance1 = tester.instance(application1.id());
+        Instance instance2 = tester.instance(application2.id());
+        Supplier<Instance> app1 = () -> tester.instance(application1.id());
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-central-1")
@@ -663,23 +679,23 @@ public class DeploymentTriggerTest {
         // System upgrades to version0 and applications deploy on that version
         Version version0 = Version.fromString("7.0");
         tester.upgradeSystem(version0);
-        tester.deployCompletely(instance1, applicationPackage);
-        tester.deployCompletely(instance2, applicationPackage);
+        tester.deployCompletely(application1, applicationPackage);
+        tester.deployCompletely(application2, applicationPackage);
 
         // version1 is released and application1 skips upgrading to that version
         Version version1 = Version.fromString("7.1");
         tester.upgradeSystem(version1);
         // Deploy application2 to keep this version present in the system
-        tester.deployCompletely(instance2, applicationPackage);
-        tester.applications().deploymentTrigger().cancelChange(instance1.id(), ALL);
+        tester.deployCompletely(application2, applicationPackage);
+        tester.applications().deploymentTrigger().cancelChange(application1.id(), ALL);
         tester.buildService().clear(); // Clear stale build jobs for cancelled change
 
         // version2 is released and application1 starts upgrading
         Version version2 = Version.fromString("7.2");
         tester.upgradeSystem(version2);
-        tester.completeUpgradeWithError(instance1, version2, applicationPackage, productionUsCentral1);
-        tester.deploy(productionUsCentral1, instance1, applicationPackage);
-        tester.deployAndNotify(instance1, applicationPackage, false, productionUsCentral1);
+        tester.completeUpgradeWithError(application1, version2, applicationPackage, productionUsCentral1);
+        tester.deploy(productionUsCentral1, instance1.id(), applicationPackage);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), false, productionUsCentral1);
         assertEquals(version2, app1.get().deployments().get(productionUsCentral1.zone(main)).version());
 
         // version2 becomes broken and upgrade targets latest non-broken
@@ -687,34 +703,34 @@ public class DeploymentTriggerTest {
         tester.computeVersionStatus();
         tester.upgrader().maintain(); // Cancel upgrades to broken version
         assertEquals("Change becomes latest non-broken version", Change.of(version1), app1.get().change());
-        tester.deployAndNotify(instance1, applicationPackage, false, productionUsCentral1);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), false, productionUsCentral1);
         Instant triggered = app1.get().deploymentJobs().jobStatus().get(productionUsCentral1).lastTriggered().get().at();
         tester.clock().advance(Duration.ofHours(1));
 
         // version1 proceeds 'til the last job, where it fails; us-central-1 is skipped, as current change is strictly dominated by what's deployed there.
-        tester.deployAndNotify(instance1, applicationPackage, true, systemTest);
-        tester.deployAndNotify(instance1, applicationPackage, true, stagingTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, stagingTest);
         assertEquals(triggered, app1.get().deploymentJobs().jobStatus().get(productionUsCentral1).lastTriggered().get().at());
-        tester.deployAndNotify(instance1, applicationPackage, false, productionEuWest1);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), false, productionEuWest1);
 
         //Eagerly triggered system and staging tests complete.
-        tester.deployAndNotify(instance1, applicationPackage, true, systemTest);
-        tester.deployAndNotify(instance1, applicationPackage, true, stagingTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, stagingTest);
 
         // Roll out a new application version, which gives a dual change -- this should trigger us-central-1, but only as long as it hasn't yet deployed there.
-        tester.jobCompletion(component).application(instance1).nextBuildNumber().uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(instance1, applicationPackage, false, productionEuWest1);
-        tester.deployAndNotify(instance1, applicationPackage, true, systemTest);
-        tester.deployAndNotify(instance1, applicationPackage, true, stagingTest);
+        tester.jobCompletion(component).application(application1).nextBuildNumber().uploadArtifact(applicationPackage).submit();
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), false, productionEuWest1);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, stagingTest);
 
-        tester.assertRunning(productionUsCentral1, instance1.id());
+        tester.assertRunning(productionUsCentral1, application1.id());
         assertEquals(version2, app1.get().deployments().get(productionUsCentral1.zone(main)).version());
         assertEquals(42, app1.get().deployments().get(productionUsCentral1.zone(main)).applicationVersion().buildNumber().getAsLong());
         assertNotEquals(triggered, app1.get().deploymentJobs().jobStatus().get(productionUsCentral1).lastTriggered().get().at());
 
         // Change has a higher application version than what is deployed -- deployment should trigger.
-        tester.deployAndNotify(instance1, applicationPackage, false, productionUsCentral1);
-        tester.deploy(productionUsCentral1, instance1, applicationPackage);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), false, productionUsCentral1);
+        tester.deploy(productionUsCentral1, instance1.id(), applicationPackage);
         assertEquals(version2, app1.get().deployments().get(productionUsCentral1.zone(main)).version());
         assertEquals(43, app1.get().deployments().get(productionUsCentral1.zone(main)).applicationVersion().buildNumber().getAsLong());
 
@@ -722,67 +738,68 @@ public class DeploymentTriggerTest {
         tester.clock().advance(Duration.ofHours(2).plus(Duration.ofSeconds(1))); // Enough time for retry
         tester.readyJobTrigger().maintain();
         // Failing job is not retried as change has been deployed
-        tester.assertNotRunning(productionUsCentral1, instance1.id());
+        tester.assertNotRunning(productionUsCentral1, application1.id());
 
         // Last job has a different deployment target, so tests need to run again.
-        tester.deployAndNotify(instance1, true, systemTest);
-        tester.deployAndNotify(instance1, true, stagingTest);
-        tester.deployAndNotify(instance1, applicationPackage, true, productionEuWest1);
+        tester.deployAndNotify(instance1.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance1.id(), Optional.empty(), true, stagingTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, productionEuWest1);
         assertFalse(app1.get().change().hasTargets());
         assertFalse(app1.get().deploymentJobs().jobStatus().get(productionUsCentral1).isSuccess());
     }
 
     @Test
     public void eachDeployTargetIsTested() {
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
-        Supplier<Instance> app = () -> tester.application(instance.id());
+        Application application = tester.createApplication("app1", "tenant1", 1, 1L);
+        Instance instance = tester.instance(application.id());
+        Supplier<Instance> app = () -> tester.instance(application.id());
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .parallel("eu-west-1", "us-east-3")
                 .build();
         // Application version 42 and platform version 6.1.
-        tester.deployCompletely(instance, applicationPackage);
+        tester.deployCompletely(application, applicationPackage);
 
         // Success in first prod zone, change cancelled between triggering and deployment to two parallel zones.
         // One of the parallel zones get a deployment, but both fail their jobs.
         Version v1 = new Version("6.1");
         Version v2 = new Version("6.2");
         tester.upgradeSystem(v2);
-        tester.deployAndNotify(instance, true, systemTest);
-        tester.deployAndNotify(instance, true, stagingTest);
-        tester.deploymentTrigger().cancelChange(instance.id(), PLATFORM);
-        tester.deploy(productionEuWest1, instance, applicationPackage);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
+        tester.deploymentTrigger().cancelChange(application.id(), PLATFORM);
+        tester.deploy(productionEuWest1, instance.id(), applicationPackage);
         assertEquals(v2, app.get().deployments().get(productionEuWest1.zone(main)).version());
         assertEquals(v1, app.get().deployments().get(productionUsEast3.zone(main)).version());
 
         // New application version should run system and staging tests against both 6.1 and 6.2, in no particular order.
-        tester.jobCompletion(component).application(instance).nextBuildNumber().uploadArtifact(applicationPackage).submit();
+        tester.jobCompletion(component).application(application).nextBuildNumber().uploadArtifact(applicationPackage).submit();
         Version firstTested = app.get().deploymentJobs().jobStatus().get(systemTest).lastTriggered().get().platform();
         assertEquals(firstTested, app.get().deploymentJobs().jobStatus().get(stagingTest).lastTriggered().get().platform());
 
-        tester.deployAndNotify(instance, true, systemTest);
-        tester.deployAndNotify(instance, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
 
         // Tests are not re-triggered, because the deployments that were tested have not yet been triggered on the tested versions.
         assertEquals(firstTested, app.get().deploymentJobs().jobStatus().get(systemTest).lastTriggered().get().platform());
         assertEquals(firstTested, app.get().deploymentJobs().jobStatus().get(stagingTest).lastTriggered().get().platform());
 
          // Finish old runs of the production jobs, which fail.
-        tester.deployAndNotify(instance, applicationPackage, false, productionEuWest1);
-        tester.deployAndNotify(instance, applicationPackage, false, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, productionEuWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, productionUsEast3);
         tester.triggerUntilQuiescence();
 
         // New upgrade is already tested for one of the jobs, which has now been triggered, and tests may run for the other job.
         assertNotEquals(firstTested, app.get().deploymentJobs().jobStatus().get(systemTest).lastTriggered().get().platform());
         assertNotEquals(firstTested, app.get().deploymentJobs().jobStatus().get(stagingTest).lastTriggered().get().platform());
-        tester.deployAndNotify(instance, true, systemTest);
-        tester.deployAndNotify(instance, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
 
         // Both jobs fail again, and must be re-triggered -- this is ok, as they are both already triggered on their current targets.
-        tester.deployAndNotify(instance, false, productionEuWest1);
-        tester.deployAndNotify(instance, false, productionUsEast3);
-        tester.deployAndNotify(instance, true, productionUsEast3);
-        tester.deployAndNotify(instance, true, productionEuWest1);
+        tester.deployAndNotify(instance.id(), Optional.empty(), false, productionEuWest1);
+        tester.deployAndNotify(instance.id(), Optional.empty(), false, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionEuWest1);
         assertFalse(app.get().change().hasTargets());
         assertEquals(43, app.get().deploymentJobs().jobStatus().get(productionEuWest1).lastSuccess().get().application().buildNumber().getAsLong());
         assertEquals(43, app.get().deploymentJobs().jobStatus().get(productionUsEast3).lastSuccess().get().application().buildNumber().getAsLong());
@@ -790,98 +807,100 @@ public class DeploymentTriggerTest {
 
     @Test
     public void eachDifferentUpgradeCombinationIsTested() {
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
-        Supplier<Instance> app = () -> tester.application(instance.id());
+        Application application = tester.createApplication("app1", "tenant1", 1, 1L);
+        Instance instance = tester.instance(application.id());
+        Supplier<Instance> app = () -> tester.instance(application.id());
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-central-1")
                 .parallel("eu-west-1", "us-east-3")
                 .build();
         // Application version 42 and platform version 6.1.
-        tester.deployCompletely(instance, applicationPackage);
+        tester.deployCompletely(application, applicationPackage);
 
         // Application partially upgrades, then a new version is released.
         Version v1 = new Version("6.1");
         Version v2 = new Version("6.2");
         tester.upgradeSystem(v2);
-        tester.deployAndNotify(instance, true, systemTest);
-        tester.deployAndNotify(instance, true, stagingTest);
-        tester.deployAndNotify(instance, true, productionUsCentral1);
-        tester.deployAndNotify(instance, true, productionEuWest1);
-        tester.deployAndNotify(instance, false, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionEuWest1);
+        tester.deployAndNotify(instance.id(), Optional.empty(), false, productionUsEast3);
         assertEquals(v2, app.get().deployments().get(ZoneId.from("prod", "us-central-1")).version());
         assertEquals(v2, app.get().deployments().get(ZoneId.from("prod", "eu-west-1")).version());
         assertEquals(v1, app.get().deployments().get(ZoneId.from("prod", "us-east-3")).version());
 
         Version v3 = new Version("6.3");
         tester.upgradeSystem(v3);
-        tester.deployAndNotify(instance, false, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.empty(), false, productionUsEast3);
 
         // See that sources for staging are: first v2, then v1.
-        tester.deployAndNotify(instance, true, systemTest);
-        tester.deployAndNotify(instance, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
         assertEquals(v2, app.get().deploymentJobs().jobStatus().get(stagingTest).lastSuccess().get().sourcePlatform().get());
-        tester.deployAndNotify(instance, true, productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionUsCentral1);
         assertEquals(v1, app.get().deploymentJobs().jobStatus().get(stagingTest).lastTriggered().get().sourcePlatform().get());
-        tester.deployAndNotify(instance, true, stagingTest);
-        tester.deployAndNotify(instance, true, productionEuWest1);
-        tester.deployAndNotify(instance, true, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionEuWest1);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionUsEast3);
     }
 
     @Test
     public void retriesFailingJobs() {
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
+        Application application = tester.createApplication("app1", "tenant1", 1, 1L);
+        Instance instance = tester.instance(application.id());
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-central-1")
                 .build();
 
         // Deploy completely on default application and platform versions
-        tester.deployCompletely(instance, applicationPackage);
+        tester.deployCompletely(application, applicationPackage);
 
         // New application change is deployed and fails in system-test for a while
-        tester.jobCompletion(component).application(instance).nextBuildNumber().uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(instance, false, systemTest);
-        tester.deployAndNotify(instance, true, stagingTest);
+        tester.jobCompletion(component).application(application).nextBuildNumber().uploadArtifact(applicationPackage).submit();
+        tester.deployAndNotify(instance.id(), Optional.empty(), false, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
 
         // Retries immediately in the first minute after failing
         tester.clock().advance(Duration.ofSeconds(59));
-        tester.jobCompletion(systemTest).application(instance).unsuccessful().submit();
+        tester.jobCompletion(systemTest).application(application).unsuccessful().submit();
         tester.readyJobTrigger().maintain();
-        tester.assertRunning(systemTest, instance.id());
+        tester.assertRunning(systemTest, application.id());
 
         // Stops immediate retry after failing for 1 minute
         tester.clock().advance(Duration.ofSeconds(1));
-        tester.jobCompletion(systemTest).application(instance).unsuccessful().submit();
+        tester.jobCompletion(systemTest).application(application).unsuccessful().submit();
         tester.readyJobTrigger().maintain();
-        tester.assertNotRunning(systemTest, instance.id());
+        tester.assertNotRunning(systemTest, application.id());
 
         // Retries after 10 minutes since previous completion as we failed within the last hour
         tester.clock().advance(Duration.ofMinutes(10).plus(Duration.ofSeconds(1)));
         tester.readyJobTrigger().maintain();
-        tester.assertRunning(systemTest, instance.id());
+        tester.assertRunning(systemTest, application.id());
 
         // Retries less frequently after 1 hour of failure
         tester.clock().advance(Duration.ofMinutes(50));
-        tester.jobCompletion(systemTest).application(instance).unsuccessful().submit();
+        tester.jobCompletion(systemTest).application(application).unsuccessful().submit();
         tester.readyJobTrigger().maintain();
-        tester.assertNotRunning(systemTest, instance.id());
+        tester.assertNotRunning(systemTest, application.id());
 
         // Retries after two hours pass since last completion
         tester.clock().advance(Duration.ofHours(2).plus(Duration.ofSeconds(1)));
         tester.readyJobTrigger().maintain();
-        tester.assertRunning(systemTest, instance.id());
+        tester.assertRunning(systemTest, application.id());
 
         // Still fails and is not retried
-        tester.jobCompletion(systemTest).application(instance).unsuccessful().submit();
+        tester.jobCompletion(systemTest).application(application).unsuccessful().submit();
         tester.readyJobTrigger().maintain();
-        tester.assertNotRunning(systemTest, instance.id());
+        tester.assertNotRunning(systemTest, application.id());
 
         // Another application change is deployed and fixes system-test. Change is triggered immediately as target changes
-        tester.jobCompletion(component).application(instance).nextBuildNumber(2).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(instance, true, systemTest);
-        tester.deployAndNotify(instance, true, stagingTest);
-        tester.deployAndNotify(instance, true, productionUsCentral1);
+        tester.jobCompletion(component).application(application).nextBuildNumber(2).uploadArtifact(applicationPackage).submit();
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionUsCentral1);
         assertTrue("Deployment completed", tester.buildService().jobs().isEmpty());
     }
 
@@ -895,11 +914,12 @@ public class DeploymentTriggerTest {
         Version version = Version.fromString("6.2");
         tester.upgradeSystem(version);
 
-        Instance app = tester.createApplication("app1", "tenant1", 1, 11L);
+        Application app = tester.createApplication("app1", "tenant1", 1, 11L);
+        Instance instance = tester.instance(app.id());
         tester.jobCompletion(component).application(app).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, JobType.stagingTest);
-        tester.deployAndNotify(app, applicationPackage, true, JobType.productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsEast3);
 
         // New version is released
         version = Version.fromString("6.3");
@@ -909,14 +929,14 @@ public class DeploymentTriggerTest {
         tester.readyJobTrigger().maintain();
 
         // Test environments pass
-        tester.deployAndNotify(app, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, JobType.stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
 
         // Production job fails and is retried
         tester.clock().advance(Duration.ofSeconds(1)); // Advance time so that we can detect jobs in progress
-        tester.deployAndNotify(app, applicationPackage, false, JobType.productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, JobType.productionUsEast3);
         assertEquals("Production job is retried", 1, tester.buildService().jobs().size());
-        assertEquals("Application has pending upgrade to " + version, version, tester.application(app.id()).change().platform().get());
+        assertEquals("Application has pending upgrade to " + version, version, tester.instance(app.id()).change().platform().get());
 
         // Another version is released, which cancels any pending upgrades to lower versions
         version = Version.fromString("6.4");
@@ -924,24 +944,24 @@ public class DeploymentTriggerTest {
         tester.upgrader().maintain();
         tester.jobCompletion(JobType.productionUsEast3).application(app).unsuccessful().submit();
         assertEquals("Application starts upgrading to new version", 2, tester.buildService().jobs().size());
-        assertEquals("Application has pending upgrade to " + version, version, tester.application(app.id()).change().platform().get());
+        assertEquals("Application has pending upgrade to " + version, version, tester.instance(app.id()).change().platform().get());
 
         // Failure re-deployer did not retry failing job for prod.us-east-3, since it no longer had an available change
         assertFalse("Job is not retried", tester.buildService().jobs().stream()
                                                 .anyMatch(j -> j.jobName().equals(JobType.productionUsEast3.jobName())));
 
         // Test environments pass
-        tester.deployAndNotify(app, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, JobType.stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
 
         // Production job fails again, and is retried
-        tester.deployAndNotify(app, applicationPackage, false, JobType.productionUsEast3);
-        assertEquals("Job is retried", Collections.singletonList(ControllerTester.buildJob(app, productionUsEast3)), tester.buildService().jobs());
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, JobType.productionUsEast3);
+        assertEquals("Job is retried", Collections.singletonList(buildJob(app.id(), productionUsEast3)), tester.buildService().jobs());
 
         // Production job finally succeeds
-        tester.deployAndNotify(app, applicationPackage, true, JobType.productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsEast3);
         assertTrue("All jobs consumed", tester.buildService().jobs().isEmpty());
-        assertFalse("No failures", tester.application(app.id()).deploymentJobs().hasFailures());
+        assertFalse("No failures", tester.instance(app.id()).deploymentJobs().hasFailures());
     }
 
     @Test
@@ -954,11 +974,12 @@ public class DeploymentTriggerTest {
         Version version = Version.fromString("6.2");
         tester.upgradeSystem(version);
 
-        Instance app = tester.createApplication("app1", "tenant1", 1, 11L);
+        Application app = tester.createApplication("app1", "tenant1", 1, 11L);
+        Instance instance = tester.instance(app.id());
         tester.jobCompletion(component).application(app).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, JobType.stagingTest);
-        tester.deployAndNotify(app, applicationPackage, true, JobType.productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsEast3);
 
         // New version is released
         version = Version.fromString("6.3");
@@ -966,29 +987,30 @@ public class DeploymentTriggerTest {
         assertEquals(version, tester.controller().versionStatus().systemVersion().get().versionNumber());
         tester.upgrader().maintain();
         tester.readyJobTrigger().maintain();
-        assertEquals("Application has pending upgrade to " + version, version, tester.application(app.id()).change().platform().get());
+        assertEquals("Application has pending upgrade to " + version, version, tester.instance(app.id()).change().platform().get());
 
         // system-test fails and is left with a retry
-        tester.deployAndNotify(app, applicationPackage, false, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, JobType.systemTest);
 
         // Another version is released
         version = Version.fromString("6.4");
         tester.upgradeSystem(version);
         assertEquals(version, tester.controller().versionStatus().systemVersion().get().versionNumber());
 
-        tester.buildService().remove(ControllerTester.buildJob(app, systemTest));
+        tester.buildService().remove(buildJob(app.id(), systemTest));
         tester.upgrader().maintain();
         tester.readyJobTrigger().maintain();
-        assertEquals("Application has pending upgrade to " + version, version, tester.application(app.id()).change().platform().get());
+        assertEquals("Application has pending upgrade to " + version, version, tester.instance(app.id()).change().platform().get());
 
         // Cancellation of outdated version and triggering on a new version is done by the upgrader.
-        assertEquals(version, tester.application(app.id()).deploymentJobs().jobStatus().get(systemTest).lastTriggered().get().platform());
+        assertEquals(version, tester.instance(app.id()).deploymentJobs().jobStatus().get(systemTest).lastTriggered().get().platform());
     }
 
     @Test
     public void testUpdatesFailingJobStatus() {
         // Setup application
-        Instance app = tester.createApplication("app1", "foo", 1, 1L);
+        Application app = tester.createApplication("app1", "foo", 1, 1L);
+        Instance instance = tester.instance(app.id());
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-west-1")
@@ -997,39 +1019,39 @@ public class DeploymentTriggerTest {
         // Initial failure
         Instant initialFailure = tester.clock().instant().truncatedTo(MILLIS);
         tester.jobCompletion(component).application(app).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app, applicationPackage, false, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, systemTest);
         assertEquals("Failure age is right at initial failure",
-                     initialFailure, tester.firstFailing(app, systemTest).get().at());
+                     initialFailure, tester.firstFailing(instance, systemTest).get().at());
 
         // Failure again -- failingSince should remain the same
         tester.clock().advance(Duration.ofMillis(1000));
-        tester.deployAndNotify(app, applicationPackage, false, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, systemTest);
         assertEquals("Failure age is right at second consecutive failure",
-                     initialFailure, tester.firstFailing(app, systemTest).get().at());
+                     initialFailure, tester.firstFailing(instance, systemTest).get().at());
 
         // Success resets failingSince
         tester.clock().advance(Duration.ofMillis(1000));
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        assertFalse(tester.firstFailing(app, systemTest).isPresent());
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
+        assertFalse(tester.firstFailing(instance, systemTest).isPresent());
 
         // Complete deployment
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsWest1);
 
         // Two repeated failures again.
         // Initial failure
         tester.clock().advance(Duration.ofMillis(1000));
         initialFailure = tester.clock().instant().truncatedTo(MILLIS);
         tester.jobCompletion(component).application(app).nextBuildNumber().uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app, applicationPackage, false, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, systemTest);
         assertEquals("Failure age is right at initial failure",
-                     initialFailure, tester.firstFailing(app, systemTest).get().at());
+                     initialFailure, tester.firstFailing(instance, systemTest).get().at());
 
         // Failure again -- failingSince should remain the same
         tester.clock().advance(Duration.ofMillis(1000));
-        tester.deployAndNotify(app, applicationPackage, false, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, systemTest);
         assertEquals("Failure age is right at second consecutive failure",
-                     initialFailure, tester.firstFailing(app, systemTest).get().at());
+                     initialFailure, tester.firstFailing(instance, systemTest).get().at());
     }
 
     @Test
@@ -1058,22 +1080,24 @@ public class DeploymentTriggerTest {
                 .build();
         Version version1 = tester.controller().versionStatus().systemVersion().get().versionNumber();
 
-        Instance app1 = tester.createApplication("application1", "tenant1", 1, 1L);
+        Application app1 = tester.createApplication("application1", "tenant1", 1, 1L);
+        Instance instance1 = tester.instance(app1.id());
 
         // First deployment: An application change
         tester.jobCompletion(component).application(app1).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app1, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app1, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app1, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, productionUsWest1);
 
         app1 = tester.application(app1.id());
         assertEquals("First deployment gets system version", version1, app1.oldestDeployedPlatform().get());
         assertEquals(version1, tester.configServer().lastPrepareVersion().get());
+        instance1 = tester.instance(instance1.id());
 
         // Unexpected deployment
-        tester.deploy(productionUsWest1, app1, applicationPackage);
-        // applications are immutable, so any change to one, including deployment changes, would give rise to a new instance.
-        assertEquals("Unexpected deployment is ignored", app1, tester.application(app1.id()));
+        tester.deploy(productionUsWest1, instance1.id(), applicationPackage);
+        // instances are immutable, so any change to one, including deployment changes, would give rise to a new instance.
+        assertEquals("Unexpected deployment is ignored", instance1, tester.instance(app1.id()));
 
         // Application change after a new system version, and a region added
         Version version2 = new Version(version1.getMajor(), version1.getMinor() + 1);
@@ -1086,16 +1110,16 @@ public class DeploymentTriggerTest {
                 .region("us-east-3")
                 .build();
         tester.jobCompletion(component).application(app1).nextBuildNumber().uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app1, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app1, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app1, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, productionUsWest1);
 
         app1 = tester.application(app1.id());
         assertEquals("Application change preserves version", version1, app1.oldestDeployedPlatform().get());
         assertEquals(version1, tester.configServer().lastPrepareVersion().get());
 
         // A deployment to the new region gets the same version
-        tester.deployAndNotify(app1, applicationPackage, true, productionUsEast3);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, productionUsEast3);
         app1 = tester.application(app1.id());
         assertEquals("Application change preserves version", version1, app1.oldestDeployedPlatform().get());
         assertEquals(version1, tester.configServer().lastPrepareVersion().get());
@@ -1104,10 +1128,10 @@ public class DeploymentTriggerTest {
         // Version upgrade changes system version
         tester.deploymentTrigger().triggerChange(app1.id(), Change.of(version2));
         tester.deploymentTrigger().triggerReadyJobs();
-        tester.deployAndNotify(app1, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app1, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app1, applicationPackage, true, productionUsWest1);
-        tester.deployAndNotify(app1, applicationPackage, true, productionUsEast3);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, productionUsWest1);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, productionUsEast3);
 
         app1 = tester.application(app1.id());
         assertEquals("Version upgrade changes version", version2, app1.oldestDeployedPlatform().get());
@@ -1124,22 +1148,25 @@ public class DeploymentTriggerTest {
         long project1 = 1;
         long project2 = 2;
         long project3 = 3;
-        Instance app1 = tester.createApplication("app1", "tenant1", project1, 1L);
-        Instance app2 = tester.createApplication("app2", "tenant2", project2, 1L);
-        Instance app3 = tester.createApplication("app3", "tenant3", project3, 1L);
+        Application app1 = tester.createApplication("app1", "tenant1", project1, 1L);
+        Application app2 = tester.createApplication("app2", "tenant2", project2, 1L);
+        Application app3 = tester.createApplication("app3", "tenant3", project3, 1L);
+        Instance instance1 = tester.instance(app1.id());
+        Instance instance2 = tester.instance(app2.id());
+        Instance instance3 = tester.instance(app3.id());
         MockBuildService mockBuildService = tester.buildService();
 
         // all applications: system-test completes successfully with some time in between, to determine trigger order.
         tester.jobCompletion(component).application(app2).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app2, applicationPackage, true, systemTest);
+        tester.deployAndNotify(instance2.id(), Optional.of(applicationPackage), true, systemTest);
         tester.clock().advance(Duration.ofMinutes(1));
 
         tester.jobCompletion(component).application(app1).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app1, applicationPackage, true, systemTest);
+        tester.deployAndNotify(instance1.id(), Optional.of(applicationPackage), true, systemTest);
         tester.clock().advance(Duration.ofMinutes(1));
 
         tester.jobCompletion(component).application(app3).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app3, applicationPackage, true, systemTest);
+        tester.deployAndNotify(instance3.id(), Optional.of(applicationPackage), true, systemTest);
 
         // all applications: staging test jobs queued
         assertEquals(3, mockBuildService.jobs().size());
@@ -1151,30 +1178,30 @@ public class DeploymentTriggerTest {
         assertJobsInOrder(jobs, tester.buildService().jobs());
 
         tester.triggerUntilQuiescence();
-        jobs.add(buildJob(app2, stagingTest));
-        jobs.add(buildJob(app1, stagingTest));
-        jobs.add(buildJob(app3, stagingTest));
+        jobs.add(buildJob(app2.id(), stagingTest));
+        jobs.add(buildJob(app1.id(), stagingTest));
+        jobs.add(buildJob(app3.id(), stagingTest));
         assertJobsInOrder(jobs, tester.buildService().jobs());
 
         // Remove the jobs for app1 and app2, and then let app3 fail with outOfCapacity.
         // All three jobs are now eligible, but the one for app3 should trigger first as an outOfCapacity-retry.
-        tester.buildService().remove(buildJob(app1, stagingTest));
-        tester.buildService().remove(buildJob(app2, stagingTest));
-        jobs.remove(buildJob(app1, stagingTest));
-        jobs.remove(buildJob(app2, stagingTest));
+        tester.buildService().remove(buildJob(app1.id(), stagingTest));
+        tester.buildService().remove(buildJob(app2.id(), stagingTest));
+        jobs.remove(buildJob(app1.id(), stagingTest));
+        jobs.remove(buildJob(app2.id(), stagingTest));
         tester.jobCompletion(stagingTest).application(app3).error(DeploymentJobs.JobError.outOfCapacity).submit();
         assertJobsInOrder(jobs, tester.buildService().jobs());
 
         tester.triggerUntilQuiescence();
-        jobs.add(buildJob(app2, stagingTest));
-        jobs.add(buildJob(app1, stagingTest));
+        jobs.add(buildJob(app2.id(), stagingTest));
+        jobs.add(buildJob(app1.id(), stagingTest));
         assertJobsInOrder(jobs, tester.buildService().jobs());
 
         // Finish deployment for apps 2 and 3, then release a new version, leaving only app1 with an application upgrade.
-        tester.deployAndNotify(app2, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app2, applicationPackage, true, productionUsEast3);
-        tester.deployAndNotify(app3, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app3, applicationPackage, true, productionUsEast3);
+        tester.deployAndNotify(instance2.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance2.id(), Optional.of(applicationPackage), true, productionUsEast3);
+        tester.deployAndNotify(instance3.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance3.id(), Optional.of(applicationPackage), true, productionUsEast3);
 
         tester.upgradeSystem(new Version("6.2"));
         // app1 also gets a new application change, so its time of availability is after the version upgrade.
@@ -1182,29 +1209,29 @@ public class DeploymentTriggerTest {
         tester.buildService().clear();
         tester.jobCompletion(component).application(app1).nextBuildNumber().uploadArtifact(applicationPackage).submit();
         jobs.clear();
-        jobs.add(buildJob(app1, stagingTest));
-        jobs.add(buildJob(app1, systemTest));
+        jobs.add(buildJob(app1.id(), stagingTest));
+        jobs.add(buildJob(app1.id(), systemTest));
         // Tests for app1 trigger before the others since it carries an application upgrade.
         assertJobsInOrder(jobs, tester.buildService().jobs());
 
         // Let the test jobs start, remove everything expect system test for app3, which fails with outOfCapacity again.
         tester.triggerUntilQuiescence();
-        tester.buildService().remove(buildJob(app1, systemTest));
-        tester.buildService().remove(buildJob(app2, systemTest));
-        tester.buildService().remove(buildJob(app1, stagingTest));
-        tester.buildService().remove(buildJob(app2, stagingTest));
-        tester.buildService().remove(buildJob(app3, stagingTest));
+        tester.buildService().remove(buildJob(app1.id(), systemTest));
+        tester.buildService().remove(buildJob(app2.id(), systemTest));
+        tester.buildService().remove(buildJob(app1.id(), stagingTest));
+        tester.buildService().remove(buildJob(app2.id(), stagingTest));
+        tester.buildService().remove(buildJob(app3.id(), stagingTest));
         tester.jobCompletion(systemTest).application(app3).error(DeploymentJobs.JobError.outOfCapacity).submit();
         jobs.clear();
-        jobs.add(buildJob(app1, stagingTest));
-        jobs.add(buildJob(app3, systemTest));
+        jobs.add(buildJob(app1.id(), stagingTest));
+        jobs.add(buildJob(app3.id(), systemTest));
         assertJobsInOrder(jobs, tester.buildService().jobs());
 
         tester.triggerUntilQuiescence();
-        jobs.add(buildJob(app2, stagingTest));
-        jobs.add(buildJob(app1, systemTest));
-        jobs.add(buildJob(app3, stagingTest));
-        jobs.add(buildJob(app2, systemTest));
+        jobs.add(buildJob(app2.id(), stagingTest));
+        jobs.add(buildJob(app1.id(), systemTest));
+        jobs.add(buildJob(app3.id(), stagingTest));
+        jobs.add(buildJob(app2.id(), systemTest));
         assertJobsInOrder(jobs, tester.buildService().jobs());
     }
 
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/InternalDeploymentTester.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/InternalDeploymentTester.java
index b6315bc6780..c0618937bdf 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/InternalDeploymentTester.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/InternalDeploymentTester.java
@@ -11,6 +11,7 @@ import com.yahoo.security.KeyUtils;
 import com.yahoo.security.SignatureAlgorithm;
 import com.yahoo.security.X509CertificateBuilder;
 import com.yahoo.test.ManualClock;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Instance;
 import com.yahoo.vespa.hosted.controller.ApplicationController;
 import com.yahoo.vespa.hosted.controller.api.identifiers.DeploymentId;
@@ -86,7 +87,8 @@ public class InternalDeploymentTester {
     public ConfigServerMock configServer() { return tester.configServer(); }
     public ApplicationController applications() { return tester.applications(); }
     public ManualClock clock() { return tester.clock(); }
-    public Instance app() { return tester.application(appId); }
+    public Application application() { return tester.application(appId); }
+    public Instance instance() { return tester.instance(appId); }
 
     public InternalDeploymentTester() {
         tester = new DeploymentTester();
@@ -145,10 +147,10 @@ public class InternalDeploymentTester {
     public ApplicationVersion deployNewSubmission() {
         ApplicationVersion applicationVersion = newSubmission();
 
-        assertFalse(app().deployments().values().stream()
-                         .anyMatch(deployment -> deployment.applicationVersion().equals(applicationVersion)));
-        assertEquals(applicationVersion, app().change().application().get());
-        assertFalse(app().change().platform().isPresent());
+        assertFalse(instance().deployments().values().stream()
+                              .anyMatch(deployment -> deployment.applicationVersion().equals(applicationVersion)));
+        assertEquals(applicationVersion, instance().change().application().get());
+        assertFalse(instance().change().platform().isPresent());
 
         runJob(JobType.systemTest);
         runJob(JobType.stagingTest);
@@ -164,18 +166,18 @@ public class InternalDeploymentTester {
      */
     public void deployNewPlatform(Version version) {
         tester.upgradeSystem(version);
-        assertFalse(app().deployments().values().stream()
-                         .anyMatch(deployment -> deployment.version().equals(version)));
-        assertEquals(version, app().change().platform().get());
-        assertFalse(app().change().application().isPresent());
+        assertFalse(instance().deployments().values().stream()
+                              .anyMatch(deployment -> deployment.version().equals(version)));
+        assertEquals(version, instance().change().platform().get());
+        assertFalse(instance().change().application().isPresent());
 
         runJob(JobType.systemTest);
         runJob(JobType.stagingTest);
         runJob(JobType.productionUsCentral1);
         runJob(JobType.productionUsWest1);
         runJob(JobType.productionUsEast3);
-        assertTrue(app().productionDeployments().values().stream()
-                        .allMatch(deployment -> deployment.version().equals(version)));
+        assertTrue(instance().productionDeployments().values().stream()
+                             .allMatch(deployment -> deployment.version().equals(version)));
         assertTrue(tester.configServer().nodeRepository()
                          .list(JobType.productionAwsUsEast1a.zone(tester.controller().system()), appId).stream()
                          .allMatch(node -> node.currentVersion().equals(version)));
@@ -185,7 +187,7 @@ public class InternalDeploymentTester {
         assertTrue(tester.configServer().nodeRepository()
                          .list(JobType.productionUsEast3.zone(tester.controller().system()), appId).stream()
                          .allMatch(node -> node.currentVersion().equals(version)));
-        assertFalse(app().change().hasTargets());
+        assertFalse(instance().change().hasTargets());
     }
 
     /**
@@ -253,10 +255,10 @@ public class InternalDeploymentTester {
         runner.run();
         assertTrue(jobs.run(run.id()).get().hasEnded());
         assertFalse(jobs.run(run.id()).get().hasFailed());
-        assertEquals(type.isProduction(), app().deployments().containsKey(zone));
+        assertEquals(type.isProduction(), instance().deployments().containsKey(zone));
         assertTrue(tester.configServer().nodeRepository().list(zone, testerId.id()).isEmpty());
 
-        if ( ! app().deployments().containsKey(zone))
+        if ( ! instance().deployments().containsKey(zone))
             routing.removeEndpoints(deployment);
         routing.removeEndpoints(new DeploymentId(testerId.id(), zone));
     }
@@ -277,7 +279,7 @@ public class InternalDeploymentTester {
      * Creates and submits a new application, and then starts the job of the given type.
      */
     public RunId newRun(JobType type) {
-        assertFalse(app().deploymentJobs().deployedInternally()); // Use this only once per test.
+        assertFalse(instance().deploymentJobs().deployedInternally()); // Use this only once per test.
         newSubmission();
         tester.readyJobTrigger().maintain();
 
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/InternalStepRunnerTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/InternalStepRunnerTest.java
index 9dcfdb00036..6813e7f1206 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/InternalStepRunnerTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/deployment/InternalStepRunnerTest.java
@@ -90,7 +90,7 @@ public class InternalStepRunnerTest {
     @Test
     public void canSwitchFromScrewdriverAndBackAgain() {
         // Deploys a default application package with default build number.
-        tester.tester().deployCompletely(tester.app(), InternalDeploymentTester.applicationPackage);
+        tester.tester().deployCompletely(tester.application(), InternalDeploymentTester.applicationPackage);
         tester.setEndpoints(appId, JobType.productionUsCentral1.zone(system()));
         tester.setEndpoints(appId, JobType.productionUsWest1.zone(system()));
         tester.setEndpoints(appId, JobType.productionUsEast3.zone(system()));
@@ -106,11 +106,11 @@ public class InternalStepRunnerTest {
 
         tester.jobs().unregister(appId);
         try {
-            tester.tester().deployCompletely(tester.app(), InternalDeploymentTester.applicationPackage, BuildJob.defaultBuildNumber + 1);
+            tester.tester().deployCompletely(tester.application(), InternalDeploymentTester.applicationPackage, BuildJob.defaultBuildNumber + 1);
             throw new IllegalStateException("Component job should get even again with build numbers to produce a change.");
         }
         catch (AssertionError expected) { }
-        tester.tester().deployCompletely(tester.app(), InternalDeploymentTester.applicationPackage, BuildJob.defaultBuildNumber + 2);
+        tester.tester().deployCompletely(tester.application(), InternalDeploymentTester.applicationPackage, BuildJob.defaultBuildNumber + 2);
     }
 
     @Test
@@ -362,7 +362,7 @@ public class InternalStepRunnerTest {
         tester.configServer().setVersion(appId, zone, version);
         tester.runner().run();
         assertEquals(1, tester.jobs().active().size());
-        assertEquals(version, tester.tester().application(appId).deployments().get(zone).version());
+        assertEquals(version, tester.tester().instance(appId).deployments().get(zone).version());
 
         try {
             tester.jobs().deploy(appId, JobType.productionApNortheast1, Optional.empty(), applicationPackage);
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/ClusterInfoMaintainerTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/ClusterInfoMaintainerTest.java
index 72b16d76864..1f5cc100fac 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/ClusterInfoMaintainerTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/ClusterInfoMaintainerTest.java
@@ -7,10 +7,13 @@ import com.yahoo.config.provision.ClusterSpec;
 import com.yahoo.config.provision.Environment;
 import com.yahoo.config.provision.HostName;
 import com.yahoo.config.provision.NodeType;
+import com.yahoo.config.provision.TenantName;
 import com.yahoo.config.provision.zone.ZoneId;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.ControllerTester;
 import com.yahoo.vespa.hosted.controller.api.integration.configserver.Node;
 import com.yahoo.vespa.hosted.controller.application.Deployment;
+import com.yahoo.vespa.hosted.controller.deployment.DeploymentTester;
 import com.yahoo.vespa.hosted.controller.persistence.MockCuratorDb;
 import org.junit.Test;
 
@@ -29,8 +32,10 @@ public class ClusterInfoMaintainerTest {
 
     @Test
     public void maintain() {
-        ApplicationId app = tester.createAndDeploy("tenant1", "domain1", "app1",
-                                                   Environment.dev, 123).id();
+        tester.createTenant("tenant1", "domain123", 321L);
+        ApplicationId app = tester.createApplication(TenantName.from("tenant1"), "app1", "default", 123).id();
+        ZoneId zone = ZoneId.from("dev", "us-east-1");
+        tester.deploy(app, zone);
 
         // Precondition: no cluster info attached to the deployments
         Deployment deployment = tester.controller().applications().get(app).get().deployments().values().stream()
@@ -38,7 +43,7 @@ public class ClusterInfoMaintainerTest {
                                       .get();
         assertEquals(0, deployment.clusterInfo().size());
 
-        addNodes(ZoneId.from("dev", "us-east-1"));
+        addNodes(zone);
         ClusterInfoMaintainer maintainer = new ClusterInfoMaintainer(tester.controller(), Duration.ofHours(1),
                                                                      new JobControl(new MockCuratorDb()));
         maintainer.maintain();
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/DeploymentExpirerTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/DeploymentExpirerTest.java
index b2ac44bf23b..f3c387eca1b 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/DeploymentExpirerTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/DeploymentExpirerTest.java
@@ -4,6 +4,7 @@ package com.yahoo.vespa.hosted.controller.maintenance;
 import com.yahoo.config.provision.Environment;
 import com.yahoo.config.provision.RegionName;
 import com.yahoo.config.provision.zone.ZoneId;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Instance;
 import com.yahoo.vespa.hosted.controller.application.ApplicationPackage;
 import com.yahoo.vespa.hosted.controller.application.Deployment;
@@ -33,11 +34,14 @@ public class DeploymentExpirerTest {
         );
         DeploymentExpirer expirer = new DeploymentExpirer(tester.controller(), Duration.ofDays(10),
                                                           new JobControl(new MockCuratorDb()));
-        Instance devApp = tester.createApplication("app1", "tenant1", 123L, 1L);
-        Instance prodApp = tester.createApplication("app2", "tenant2", 456L, 2L);
+        Application devApp = tester.createApplication("app1", "tenant1", 123L, 1L);
+        Application prodApp = tester.createApplication("app2", "tenant2", 456L, 2L);
+
+        Instance devInstance = tester.instance(devApp.id());
+        Instance prodInstance = tester.instance(prodApp.id());
 
         // Deploy dev
-        tester.controllerTester().deploy(devApp, tester.controllerTester().toZone(Environment.dev));
+        tester.controllerTester().deploy(devInstance.id(), tester.controllerTester().toZone(Environment.dev));
 
         // Deploy prod
         ApplicationPackage prodAppPackage = new ApplicationPackageBuilder()
@@ -45,19 +49,19 @@ public class DeploymentExpirerTest {
                 .build();
         tester.deployCompletely(prodApp, prodAppPackage);
 
-        assertEquals(1, permanentDeployments(devApp).size());
-        assertEquals(1, permanentDeployments(prodApp).size());
+        assertEquals(1, permanentDeployments(devInstance).size());
+        assertEquals(1, permanentDeployments(prodInstance).size());
 
         // Not expired at first
         expirer.maintain();
-        assertEquals(1, permanentDeployments(devApp).size());
-        assertEquals(1, permanentDeployments(prodApp).size());
+        assertEquals(1, permanentDeployments(devInstance).size());
+        assertEquals(1, permanentDeployments(prodInstance).size());
 
         // The dev application is removed
         tester.clock().advance(Duration.ofDays(15));
         expirer.maintain();
-        assertEquals(0, permanentDeployments(devApp).size());
-        assertEquals(1, permanentDeployments(prodApp).size());
+        assertEquals(0, permanentDeployments(devInstance).size());
+        assertEquals(1, permanentDeployments(prodInstance).size());
     }
 
     private List<Deployment> permanentDeployments(Instance instance) {
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/DeploymentIssueReporterTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/DeploymentIssueReporterTest.java
index d20ccdf5963..7a4d6821637 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/DeploymentIssueReporterTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/DeploymentIssueReporterTest.java
@@ -4,6 +4,7 @@ package com.yahoo.vespa.hosted.controller.maintenance;
 import com.yahoo.component.Version;
 import com.yahoo.config.provision.ApplicationId;
 import com.yahoo.config.provision.Environment;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Instance;
 import com.yahoo.vespa.hosted.controller.api.integration.organization.Contact;
 import com.yahoo.vespa.hosted.controller.api.integration.organization.IssueId;
@@ -78,24 +79,24 @@ public class DeploymentIssueReporterTest {
         tester.controllerTester().createTenant("tenant3", "domain3", 1L, contact);
 
         // Create and deploy one application for each of three tenants.
-        Instance app1 = tester.createApplication("application1", "tenant1", projectId1, propertyId1);
-        Instance app2 = tester.createApplication("application2", "tenant2", projectId2, propertyId2);
-        Instance app3 = tester.createApplication("application3", "tenant3", projectId3, propertyId3);
+        Application app1 = tester.createApplication("application1", "tenant1", projectId1, propertyId1);
+        Application app2 = tester.createApplication("application2", "tenant2", projectId2, propertyId2);
+        Application app3 = tester.createApplication("application3", "tenant3", projectId3, propertyId3);
 
         // NOTE: All maintenance should be idempotent within a small enough time interval, so maintain is called twice in succession throughout.
 
         // apps 1 and 3 have one failure each.
         tester.jobCompletion(component).application(app1).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app1, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app1, applicationPackage, false, stagingTest);
+        tester.deployAndNotify(app1.id(), applicationPackage, true, systemTest);
+        tester.deployAndNotify(app1.id(), applicationPackage, false, stagingTest);
 
         // app2 is successful, but will fail later.
         tester.deployCompletely(app2, canaryPackage);
 
         tester.jobCompletion(component).application(app3).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app3, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app3, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app3, applicationPackage, false, productionUsWest1);
+        tester.deployAndNotify(app3.id(), applicationPackage, true, systemTest);
+        tester.deployAndNotify(app3.id(), applicationPackage, true, stagingTest);
+        tester.deployAndNotify(app3.id(), applicationPackage, false, productionUsWest1);
 
         reporter.maintain();
         reporter.maintain();
@@ -130,7 +131,7 @@ public class DeploymentIssueReporterTest {
 
 
         // app3 fixes their problems, but the ticket for app3 is left open; see the resolved ticket is not escalated when another escalation period has passed.
-        tester.deployAndNotify(app3, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(app3.id(), applicationPackage, true, productionUsWest1);
         tester.clock().advance(maxInactivity.plus(Duration.ofDays(1)));
 
         reporter.maintain();
@@ -142,7 +143,7 @@ public class DeploymentIssueReporterTest {
 
         // app3 now has a new failure past max failure age; see that a new issue is filed.
         tester.jobCompletion(component).application(app3).nextBuildNumber().uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app3, applicationPackage, false, systemTest);
+        tester.deployAndNotify(app3.id(), applicationPackage, false, systemTest);
         tester.clock().advance(maxInactivity.plus(maxFailureAge));
 
         reporter.maintain();
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/DeploymentMetricsMaintainerTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/DeploymentMetricsMaintainerTest.java
index c4a835cd7e7..7f537c2e4bb 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/DeploymentMetricsMaintainerTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/DeploymentMetricsMaintainerTest.java
@@ -37,10 +37,10 @@ public class DeploymentMetricsMaintainerTest {
     @Test
     public void updates_metrics() {
         var application = tester.createApplication("app1", "tenant1", 123L, 1L);
-        deploy(application, Version.fromString("7.1"));
+        deploy(application.id(), Version.fromString("7.1"));
 
         DeploymentMetricsMaintainer maintainer = maintainer(tester.controller());
-        Supplier<Instance> app = () -> tester.application(application.id());
+        Supplier<Instance> app = () -> tester.instance(application.id());
         Supplier<Deployment> deployment = () -> app.get().deployments().values().stream().findFirst().get();
 
         // No metrics gathered yet
@@ -51,7 +51,7 @@ public class DeploymentMetricsMaintainerTest {
         assertFalse("Never received any writes", deployment.get().activity().lastWritten().isPresent());
 
         // Only get application metrics for old version
-        deploy(app.get(), Version.fromString("6.3.3"));
+        deploy(application.id(), Version.fromString("6.3.3"));
         maintainer.maintain();
         assertEquals(0, app.get().metrics().queryServiceQuality(), 0);
         assertEquals(0, deployment.get().metrics().documentCount(), 0);
@@ -60,7 +60,7 @@ public class DeploymentMetricsMaintainerTest {
         assertFalse("Never received any writes", deployment.get().activity().lastWritten().isPresent());
 
         // Metrics are gathered and saved to application
-        deploy(app.get(), Version.fromString("7.5.5"));
+        deploy(application.id(), Version.fromString("7.5.5"));
         var metrics0 = Map.of(ClusterMetrics.QUERIES_PER_SECOND, 1D,
                               ClusterMetrics.FEED_PER_SECOND, 2D,
                               ClusterMetrics.DOCUMENT_COUNT, 3D,
@@ -127,8 +127,8 @@ public class DeploymentMetricsMaintainerTest {
         return new DeploymentMetricsMaintainer(controller, Duration.ofDays(1), new JobControl(controller.curator()));
     }
 
-    private void deploy(Instance instance, Version version) {
-        tester.controllerTester().deploy(instance,
+    private void deploy(ApplicationId id, Version version) {
+        tester.controllerTester().deploy(id,
                                          ZoneId.from(Environment.dev, RegionName.from("us-east-1")),
                                          Optional.of(new ApplicationPackage(new byte[0])),
                                          false,
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/MetricsReporterTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/MetricsReporterTest.java
index 46e6d9c3f50..11749afb6ed 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/MetricsReporterTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/MetricsReporterTest.java
@@ -2,8 +2,10 @@
 package com.yahoo.vespa.hosted.controller.maintenance;
 
 import com.yahoo.component.Version;
+import com.yahoo.config.provision.ApplicationId;
 import com.yahoo.config.provision.Environment;
 import com.yahoo.config.provision.zone.ZoneId;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Instance;
 import com.yahoo.vespa.hosted.controller.Controller;
 import com.yahoo.vespa.hosted.controller.ControllerTester;
@@ -18,6 +20,7 @@ import com.yahoo.vespa.hosted.controller.persistence.MockCuratorDb;
 import org.junit.Test;
 
 import java.time.Duration;
+import java.util.Optional;
 
 import static com.yahoo.vespa.hosted.controller.api.integration.deployment.JobType.component;
 import static com.yahoo.vespa.hosted.controller.api.integration.deployment.JobType.productionUsWest1;
@@ -46,10 +49,10 @@ public class MetricsReporterTest {
         assertEquals(0.0, metrics.getMetric(MetricsReporter.DEPLOYMENT_FAIL_METRIC));
 
         // Deploy all apps successfully
-        Instance app1 = tester.createApplication("app1", "tenant1", 1, 11L);
-        Instance app2 = tester.createApplication("app2", "tenant1", 2, 22L);
-        Instance app3 = tester.createApplication("app3", "tenant1", 3, 33L);
-        Instance app4 = tester.createApplication("app4", "tenant1", 4, 44L);
+        Application app1 = tester.createApplication("app1", "tenant1", 1, 11L);
+        Application app2 = tester.createApplication("app2", "tenant1", 2, 22L);
+        Application app3 = tester.createApplication("app3", "tenant1", 3, 33L);
+        Application app4 = tester.createApplication("app4", "tenant1", 4, 44L);
         tester.deployCompletely(app1, applicationPackage);
         tester.deployCompletely(app2, applicationPackage);
         tester.deployCompletely(app3, applicationPackage);
@@ -60,7 +63,7 @@ public class MetricsReporterTest {
 
         // 1 app fails system-test
         tester.jobCompletion(component).application(app4).nextBuildNumber().uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app4, applicationPackage, false, systemTest);
+        tester.deployAndNotify(app4.id(), Optional.of(applicationPackage), false, systemTest);
 
         metricsReporter.maintain();
         assertEquals(25.0, metrics.getMetric(MetricsReporter.DEPLOYMENT_FAIL_METRIC));
@@ -76,25 +79,25 @@ public class MetricsReporterTest {
 
         MetricsReporter reporter = createReporter(tester.controller());
 
-        Instance app = tester.createApplication("app1", "tenant1", 1, 11L);
+        Application app = tester.createApplication("app1", "tenant1", 1, 11L);
         tester.deployCompletely(app, applicationPackage);
         reporter.maintain();
-        assertEquals(Duration.ZERO, getAverageDeploymentDuration(app)); // An exceptionally fast deployment :-)
+        assertEquals(Duration.ZERO, getAverageDeploymentDuration(app.id())); // An exceptionally fast deployment :-)
 
         // App spends 3 hours deploying
         tester.jobCompletion(component).application(app).nextBuildNumber().uploadArtifact(applicationPackage).submit();
         tester.clock().advance(Duration.ofHours(1));
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
+        tester.deployAndNotify(app.id(), Optional.of(applicationPackage), true, systemTest);
 
         tester.clock().advance(Duration.ofMinutes(30));
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
+        tester.deployAndNotify(app.id(), Optional.of(applicationPackage), true, stagingTest);
 
         tester.clock().advance(Duration.ofMinutes(90));
-        tester.deployAndNotify(app, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(app.id(), Optional.of(applicationPackage), true, productionUsWest1);
         reporter.maintain();
 
         // Average time is 1 hour (system-test) + 90 minutes (staging-test runs in parallel with system-test) + 90 minutes (production) / 3 jobs
-        assertEquals(Duration.ofMinutes(80), getAverageDeploymentDuration(app));
+        assertEquals(Duration.ofMinutes(80), getAverageDeploymentDuration(app.id()));
 
         // Another deployment starts and stalls for 12 hours
         tester.jobCompletion(component).application(app).nextBuildNumber(2).uploadArtifact(applicationPackage).submit();
@@ -105,7 +108,7 @@ public class MetricsReporterTest {
                              .plus(Duration.ofHours(12)) // hanging staging-test
                              .plus(Duration.ofMinutes(90)) // previous production job
                              .dividedBy(3), // Total number of orchestrated jobs
-                     getAverageDeploymentDuration(app));
+                     getAverageDeploymentDuration(app.id()));
     }
 
     @Test
@@ -117,46 +120,46 @@ public class MetricsReporterTest {
                 .build();
 
         MetricsReporter reporter = createReporter(tester.controller());
-        Instance app = tester.createApplication("app1", "tenant1", 1, 11L);
+        Application app = tester.createApplication("app1", "tenant1", 1, 11L);
 
         // Initial deployment without failures
         tester.deployCompletely(app, applicationPackage);
         reporter.maintain();
-        assertEquals(0, getDeploymentsFailingUpgrade(app));
+        assertEquals(0, getDeploymentsFailingUpgrade(app.id()));
 
         // Failing application change is not counted
         tester.jobCompletion(component).application(app).nextBuildNumber().uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app, applicationPackage, false, systemTest);
+        tester.deployAndNotify(app.id(), Optional.of(applicationPackage), false, systemTest);
         reporter.maintain();
-        assertEquals(0, getDeploymentsFailingUpgrade(app));
+        assertEquals(0, getDeploymentsFailingUpgrade(app.id()));
 
         // Application change completes
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(app.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(app.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(app.id(), Optional.of(applicationPackage), true, productionUsWest1);
         assertFalse("Change deployed", tester.controller().applications().require(app.id()).change().hasTargets());
 
         // New versions is released and upgrade fails in test environments
         Version version = Version.fromString("7.1");
         tester.upgradeSystem(version);
         tester.upgrader().maintain();
-        tester.deployAndNotify(app, applicationPackage, false, systemTest);
-        tester.deployAndNotify(app, applicationPackage, false, stagingTest);
+        tester.deployAndNotify(app.id(), Optional.of(applicationPackage), false, systemTest);
+        tester.deployAndNotify(app.id(), Optional.of(applicationPackage), false, stagingTest);
         reporter.maintain();
-        assertEquals(2, getDeploymentsFailingUpgrade(app));
+        assertEquals(2, getDeploymentsFailingUpgrade(app.id()));
 
         // Test and staging pass and upgrade fails in production
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app, applicationPackage, false, productionUsWest1);
+        tester.deployAndNotify(app.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(app.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(app.id(), Optional.of(applicationPackage), false, productionUsWest1);
         reporter.maintain();
-        assertEquals(1, getDeploymentsFailingUpgrade(app));
+        assertEquals(1, getDeploymentsFailingUpgrade(app.id()));
 
         // Upgrade eventually succeeds
-        tester.deployAndNotify(app, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(app.id(), Optional.of(applicationPackage), true, productionUsWest1);
         assertFalse("Upgrade deployed", tester.controller().applications().require(app.id()).change().hasTargets());
         reporter.maintain();
-        assertEquals(0, getDeploymentsFailingUpgrade(app));
+        assertEquals(0, getDeploymentsFailingUpgrade(app.id()));
     }
 
     @Test
@@ -168,12 +171,12 @@ public class MetricsReporterTest {
                 .region("us-east-3")
                 .build();
         MetricsReporter reporter = createReporter(tester.controller());
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 11L);
-        tester.configServer().generateWarnings(new DeploymentId(instance.id(), ZoneId.from("prod", "us-west-1")), 3);
-        tester.configServer().generateWarnings(new DeploymentId(instance.id(), ZoneId.from("prod", "us-east-3")), 4);
-        tester.deployCompletely(instance, applicationPackage);
+        Application application = tester.createApplication("app1", "tenant1", 1, 11L);
+        tester.configServer().generateWarnings(new DeploymentId(application.id(), ZoneId.from("prod", "us-west-1")), 3);
+        tester.configServer().generateWarnings(new DeploymentId(application.id(), ZoneId.from("prod", "us-east-3")), 4);
+        tester.deployCompletely(application, applicationPackage);
         reporter.maintain();
-        assertEquals(4, getDeploymentWarnings(instance));
+        assertEquals(4, getDeploymentWarnings(application.id()));
     }
 
     @Test
@@ -185,7 +188,7 @@ public class MetricsReporterTest {
         MetricsReporter reporter = createReporter(tester.tester().controller());
         reporter.maintain();
         assertEquals(tester.clock().instant().getEpochSecond() - 1,
-                     getMetric(MetricsReporter.DEPLOYMENT_BUILD_AGE_SECONDS, tester.app()));
+                     getMetric(MetricsReporter.DEPLOYMENT_BUILD_AGE_SECONDS, tester.instance().id()));
     }
 
     @Test
@@ -198,11 +201,11 @@ public class MetricsReporterTest {
                 .region("us-east-3")
                 .build();
         MetricsReporter reporter = createReporter(tester.controller());
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 11L);
+        Application application = tester.createApplication("app1", "tenant1", 1, 11L);
         reporter.maintain();
         assertEquals("Queue is empty initially", 0, metrics.getMetric(MetricsReporter.NAME_SERVICE_REQUESTS_QUEUED).intValue());
 
-        tester.deployCompletely(instance, applicationPackage);
+        tester.deployCompletely(application, applicationPackage);
         reporter.maintain();
         assertEquals("Deployment queues name services requests", 6, metrics.getMetric(MetricsReporter.NAME_SERVICE_REQUESTS_QUEUED).intValue());
 
@@ -211,31 +214,31 @@ public class MetricsReporterTest {
         assertEquals("Queue consumed", 0, metrics.getMetric(MetricsReporter.NAME_SERVICE_REQUESTS_QUEUED).intValue());
     }
 
-    private Duration getAverageDeploymentDuration(Instance instance) {
-        return Duration.ofSeconds(getMetric(MetricsReporter.DEPLOYMENT_AVERAGE_DURATION, instance).longValue());
+    private Duration getAverageDeploymentDuration(ApplicationId id) {
+        return Duration.ofSeconds(getMetric(MetricsReporter.DEPLOYMENT_AVERAGE_DURATION, id).longValue());
     }
 
-    private int getDeploymentsFailingUpgrade(Instance instance) {
-        return getMetric(MetricsReporter.DEPLOYMENT_FAILING_UPGRADES, instance).intValue();
+    private int getDeploymentsFailingUpgrade(ApplicationId id) {
+        return getMetric(MetricsReporter.DEPLOYMENT_FAILING_UPGRADES, id).intValue();
     }
 
-    private int getDeploymentWarnings(Instance instance) {
-        return getMetric(MetricsReporter.DEPLOYMENT_WARNINGS, instance).intValue();
+    private int getDeploymentWarnings(ApplicationId id) {
+        return getMetric(MetricsReporter.DEPLOYMENT_WARNINGS, id).intValue();
     }
 
-    private Number getMetric(String name, Instance instance) {
-        return metrics.getMetric((dimensions) -> instance.id().tenant().value().equals(dimensions.get("tenant")) &&
-                                                 appDimension(instance).equals(dimensions.get("app")),
+    private Number getMetric(String name, ApplicationId id) {
+        return metrics.getMetric((dimensions) -> id.tenant().value().equals(dimensions.get("tenant")) &&
+                                                 appDimension(id).equals(dimensions.get("app")),
                                  name)
-                      .orElseThrow(() -> new RuntimeException("Expected metric to exist for " + instance.id()));
+                      .orElseThrow(() -> new RuntimeException("Expected metric to exist for " + id));
     }
 
     private MetricsReporter createReporter(Controller controller) {
         return new MetricsReporter(controller, metrics, new JobControl(new MockCuratorDb()));
     }
 
-    private static String appDimension(Instance instance) {
-        return instance.id().application().value() + "." + instance.id().instance().value();
+    private static String appDimension(ApplicationId id) {
+        return id.application().value() + "." + id.instance().value();
     }
 
 }
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/OutstandingChangeDeployerTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/OutstandingChangeDeployerTest.java
index 4bd1bfcffae..e438aab007f 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/OutstandingChangeDeployerTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/OutstandingChangeDeployerTest.java
@@ -3,6 +3,7 @@ package com.yahoo.vespa.hosted.controller.maintenance;
 
 import com.yahoo.component.Version;
 import com.yahoo.config.provision.Environment;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Instance;
 import com.yahoo.vespa.hosted.controller.api.integration.BuildService;
 import com.yahoo.vespa.hosted.controller.api.integration.deployment.JobType;
@@ -16,6 +17,7 @@ import org.junit.Test;
 
 import java.time.Duration;
 import java.util.List;
+import java.util.Optional;
 
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -36,49 +38,49 @@ public class OutstandingChangeDeployerTest {
                 .region("us-west-1")
                 .build();
 
-        tester.createAndDeploy("app1", 11, applicationPackage);
-        tester.createAndDeploy("app2", 22, applicationPackage);
+        Application app1 = tester.createAndDeploy("app1", 11, applicationPackage);
+        Application app2 = tester.createAndDeploy("app2", 22, applicationPackage);
 
         Version version = new Version(6, 2);
-        tester.deploymentTrigger().triggerChange(tester.application("app1").id(), Change.of(version));
+        tester.deploymentTrigger().triggerChange(tester.instance("app1").id(), Change.of(version));
         tester.deploymentTrigger().triggerReadyJobs();
 
-        assertEquals(Change.of(version), tester.application("app1").change());
-        assertFalse(tester.application("app1").outstandingChange().hasTargets());
+        assertEquals(Change.of(version), tester.instance("app1").change());
+        assertFalse(tester.instance("app1").outstandingChange().hasTargets());
 
         tester.jobCompletion(JobType.component)
-              .application(tester.application("app1"))
+              .application(app1)
               .sourceRevision(new SourceRevision("repository1","master", "cafed00d"))
               .nextBuildNumber()
               .uploadArtifact(applicationPackage)
               .submit();
 
-        Instance app = tester.application("app1");
-        assertTrue(app.outstandingChange().hasTargets());
-        assertEquals("1.0.43-cafed00d", app.outstandingChange().application().get().id());
+        Instance instance = tester.instance("app1");
+        assertTrue(instance.outstandingChange().hasTargets());
+        assertEquals("1.0.43-cafed00d", instance.outstandingChange().application().get().id());
         assertEquals(2, tester.buildService().jobs().size());
 
         deployer.maintain();
         tester.deploymentTrigger().triggerReadyJobs();
         assertEquals("No effect as job is in progress", 2, tester.buildService().jobs().size());
-        assertEquals("1.0.43-cafed00d", app.outstandingChange().application().get().id());
+        assertEquals("1.0.43-cafed00d", instance.outstandingChange().application().get().id());
 
-        tester.deployAndNotify(app, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, JobType.stagingTest);
-        tester.deployAndNotify(app, applicationPackage, true, JobType.productionUsWest1);
-        tester.deployAndNotify(app, applicationPackage, true, JobType.systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, JobType.stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, JobType.stagingTest);
         assertEquals("Upgrade done", 0, tester.buildService().jobs().size());
 
         deployer.maintain();
         tester.deploymentTrigger().triggerReadyJobs();
-        app = tester.application("app1");
-        assertEquals("1.0.43-cafed00d", app.change().application().get().id());
+        instance = tester.instance("app1");
+        assertEquals("1.0.43-cafed00d", instance.change().application().get().id());
         List<BuildService.BuildJob> jobs = tester.buildService().jobs();
         assertEquals(1, jobs.size());
         assertEquals(JobType.productionUsWest1.jobName(), jobs.get(0).jobName());
         assertEquals(11, jobs.get(0).projectId());
-        assertFalse(tester.application("app1").outstandingChange().hasTargets());
+        assertFalse(tester.instance("app1").outstandingChange().hasTargets());
     }
 
 }
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/RotationStatusUpdaterTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/RotationStatusUpdaterTest.java
index 7f97f1bc4a9..0eaa3e19927 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/RotationStatusUpdaterTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/RotationStatusUpdaterTest.java
@@ -42,7 +42,7 @@ public class RotationStatusUpdaterTest {
                 .build();
         tester.deployCompletely(application, applicationPackage);
 
-        Supplier<Instance> app = () -> tester.application(application.id());
+        Supplier<Instance> app = () -> tester.instance(application.id());
         Supplier<Deployment> deployment1 = () -> app.get().deployments().get(zone1);
         Supplier<Deployment> deployment2 = () -> app.get().deployments().get(zone2);
         Supplier<Deployment> deployment3 = () -> app.get().deployments().get(zone3);
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/RoutingPoliciesTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/RoutingPoliciesTest.java
index 1763ff74fb0..c1e1f0d0607 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/RoutingPoliciesTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/RoutingPoliciesTest.java
@@ -5,6 +5,7 @@ import com.yahoo.config.provision.ApplicationId;
 import com.yahoo.config.provision.ClusterSpec;
 import com.yahoo.config.provision.HostName;
 import com.yahoo.config.provision.zone.ZoneId;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Instance;
 import com.yahoo.vespa.hosted.controller.api.identifiers.DeploymentId;
 import com.yahoo.vespa.hosted.controller.api.integration.configserver.LoadBalancer;
@@ -38,8 +39,10 @@ public class RoutingPoliciesTest {
 
     private final DeploymentTester tester = new DeploymentTester();
 
-    private final Instance app1 = tester.createApplication("app1", "tenant1", 1, 1L);
-    private final Instance app2 = tester.createApplication("app2", "tenant1", 1, 1L);
+    private final Application app1 = tester.createApplication("app1", "tenant1", 1, 1L);
+    private final Application app2 = tester.createApplication("app2", "tenant1", 1, 1L);
+    private final Instance instance1 = tester.instance(app1.id());
+    private final Instance instance2 = tester.instance(app2.id());
 
     private final ZoneId zone1 = ZoneId.from("prod", "us-west-1");
     private final ZoneId zone2 = ZoneId.from("prod", "us-central-1");
@@ -152,12 +155,12 @@ public class RoutingPoliciesTest {
                 "c1.app1.tenant1.us-central-1.vespa.oath.cloud"
         );
         assertEquals(expectedRecords, recordNames());
-        assertEquals(4, policies(app1).size());
+        assertEquals(4, policies(instance1).size());
 
         // Next deploy does nothing
         tester.deployCompletely(app1, applicationPackage, ++buildNumber);
         assertEquals(expectedRecords, recordNames());
-        assertEquals(4, policies(app1).size());
+        assertEquals(4, policies(instance1).size());
 
         // Add 1 cluster in each zone and deploy
         provisionLoadBalancers(clustersPerZone + 1, app1.id(), zone1, zone2);
@@ -171,7 +174,7 @@ public class RoutingPoliciesTest {
                 "c2.app1.tenant1.us-central-1.vespa.oath.cloud"
         );
         assertEquals(expectedRecords, recordNames());
-        assertEquals(6, policies(app1).size());
+        assertEquals(6, policies(instance1).size());
 
         // Deploy another application
         provisionLoadBalancers(clustersPerZone, app2.id(), zone1, zone2);
@@ -189,7 +192,7 @@ public class RoutingPoliciesTest {
                 "c1.app2.tenant1.us-west-1.vespa.oath.cloud"
         );
         assertEquals(expectedRecords, recordNames());
-        assertEquals(4, policies(app2).size());
+        assertEquals(4, policies(instance2).size());
 
         // Deploy removes cluster from app1
         provisionLoadBalancers(clustersPerZone, app1.id(), zone1, zone2);
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/UpgraderTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/UpgraderTest.java
index a54d6f3ece7..498c20e69c5 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/UpgraderTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/maintenance/UpgraderTest.java
@@ -5,6 +5,7 @@ import com.yahoo.component.Version;
 import com.yahoo.config.provision.Environment;
 import com.yahoo.config.provision.RegionName;
 import com.yahoo.config.provision.zone.ZoneId;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Instance;
 import com.yahoo.vespa.hosted.controller.ControllerTester;
 import com.yahoo.vespa.hosted.controller.api.integration.deployment.JobType;
@@ -54,12 +55,19 @@ public class UpgraderTest {
         assertEquals("No applications: Nothing to do", 0, tester.buildService().jobs().size());
 
         // Setup applications
-        Instance canary0 = tester.createAndDeploy("canary0", 1, "canary");
-        Instance canary1 = tester.createAndDeploy("canary1", 2, "canary");
-        Instance default0 = tester.createAndDeploy("default0", 3, "default");
-        Instance default1 = tester.createAndDeploy("default1", 4, "default");
-        Instance default2 = tester.createAndDeploy("default2", 5, "default");
-        Instance conservative0 = tester.createAndDeploy("conservative0", 6, "conservative");
+        Application canary0 = tester.createAndDeploy("canary0", 1, "canary");
+        Application canary1 = tester.createAndDeploy("canary1", 2, "canary");
+        Application default0 = tester.createAndDeploy("default0", 3, "default");
+        Application default1 = tester.createAndDeploy("default1", 4, "default");
+        Application default2 = tester.createAndDeploy("default2", 5, "default");
+        Application conservative0 = tester.createAndDeploy("conservative0", 6, "conservative");
+
+        Instance canary0default = tester.instance(canary0.id());
+        Instance canary1default = tester.instance(canary1.id());
+        Instance default0default = tester.instance(default0.id());
+        Instance default1default = tester.instance(default1.id());
+        Instance default2default = tester.instance(default2.id());
+        Instance conservative0default = tester.instance(conservative0.id());
 
         tester.upgrader().maintain();
         tester.triggerUntilQuiescence();
@@ -126,9 +134,9 @@ public class UpgraderTest {
         tester.upgradeSystem(version3);
         assertEquals(version3, tester.controller().versionStatus().systemVersion().get().versionNumber());
         tester.upgrader().maintain();
-        tester.buildService().remove(ControllerTester.buildJob(canary0, stagingTest));
-        tester.buildService().remove(ControllerTester.buildJob(canary1, systemTest));
-        tester.buildService().remove(ControllerTester.buildJob(canary1, stagingTest));
+        tester.buildService().remove(ControllerTester.buildJob(canary0.id(), stagingTest));
+        tester.buildService().remove(ControllerTester.buildJob(canary1.id(), systemTest));
+        tester.buildService().remove(ControllerTester.buildJob(canary1.id(), stagingTest));
         tester.triggerUntilQuiescence();
 
         assertEquals("New system version: Should upgrade Canaries", 4, tester.buildService().jobs().size());
@@ -164,10 +172,10 @@ public class UpgraderTest {
         // Deploy application change
         tester.jobCompletion(component).application(default0).nextBuildNumber().uploadArtifact(DeploymentTester.applicationPackage("default")).submit();
         tester.jobCompletion(stagingTest).application(default0).unsuccessful().submit();
-        tester.deployAndNotify(default0, "default", true, systemTest);
-        tester.deployAndNotify(default0, "default", true, stagingTest);
-        tester.deployAndNotify(default0, "default", true, productionUsWest1);
-        tester.deployAndNotify(default0, "default", true, productionUsEast3);
+        tester.deployAndNotify(default0default.id(), DeploymentTester.applicationPackage("default"), true, systemTest);
+        tester.deployAndNotify(default0default.id(), DeploymentTester.applicationPackage("default"), true, stagingTest);
+        tester.deployAndNotify(default0default.id(), DeploymentTester.applicationPackage("default"), true, productionUsWest1);
+        tester.deployAndNotify(default0default.id(), DeploymentTester.applicationPackage("default"), true, productionUsEast3);
 
         tester.upgradeSystem(version3);
         assertEquals(VespaVersion.Confidence.high, tester.controller().versionStatus().systemVersion().get().confidence());
@@ -183,8 +191,8 @@ public class UpgraderTest {
 
         // --- Starting upgrading to a new version which breaks, causing upgrades to commence on the previous version
         Version version4 = Version.fromString("6.6");
-        Instance default3 = tester.createAndDeploy("default3", 7, "default"); // need 4 to break a version
-        Instance default4 = tester.createAndDeploy("default4", 8, "default");
+        Application default3 = tester.createAndDeploy("default3", 7, "default"); // need 4 to break a version
+        Application default4 = tester.createAndDeploy("default4", 8, "default");
         tester.upgradeSystem(version4);
         tester.upgrader().maintain(); // cause canary upgrades to new version
         tester.triggerUntilQuiescence();
@@ -196,11 +204,11 @@ public class UpgraderTest {
         tester.triggerUntilQuiescence();
 
         assertEquals("Upgrade of defaults are scheduled", 10, tester.buildService().jobs().size());
-        assertEquals(version4, tester.application(default0.id()).change().platform().get());
-        assertEquals(version4, tester.application(default1.id()).change().platform().get());
-        assertEquals(version4, tester.application(default2.id()).change().platform().get());
-        assertEquals(version4, tester.application(default3.id()).change().platform().get());
-        assertEquals(version4, tester.application(default4.id()).change().platform().get());
+        assertEquals(version4, tester.instance(default0.id()).change().platform().get());
+        assertEquals(version4, tester.instance(default1.id()).change().platform().get());
+        assertEquals(version4, tester.instance(default2.id()).change().platform().get());
+        assertEquals(version4, tester.instance(default3.id()).change().platform().get());
+        assertEquals(version4, tester.instance(default4.id()).change().platform().get());
 
         tester.completeUpgrade(default0, version4, "default");
         // State: Default applications started upgrading to version4 (and one completed)
@@ -216,11 +224,11 @@ public class UpgraderTest {
         tester.triggerUntilQuiescence();
 
         assertEquals("Upgrade of defaults are scheduled", 10, tester.buildService().jobs().size());
-        assertEquals(version5, tester.application(default0.id()).change().platform().get());
-        assertEquals(version4, tester.application(default1.id()).change().platform().get());
-        assertEquals(version4, tester.application(default2.id()).change().platform().get());
-        assertEquals(version4, tester.application(default3.id()).change().platform().get());
-        assertEquals(version4, tester.application(default4.id()).change().platform().get());
+        assertEquals(version5, tester.instance(default0.id()).change().platform().get());
+        assertEquals(version4, tester.instance(default1.id()).change().platform().get());
+        assertEquals(version4, tester.instance(default2.id()).change().platform().get());
+        assertEquals(version4, tester.instance(default3.id()).change().platform().get());
+        assertEquals(version4, tester.instance(default4.id()).change().platform().get());
 
         tester.completeUpgrade(default1, version4, "default");
         tester.completeUpgrade(default2, version4, "default");
@@ -252,7 +260,7 @@ public class UpgraderTest {
         assertEquals("Upgrade of defaults are scheduled on " + version4 + " instead, since " + version5 + " is broken: " +
                      "This is default3 since it failed upgrade on both " + version4 + " and " + version5,
                      2, tester.buildService().jobs().size());
-        assertEquals(version4, tester.application(default3.id()).change().platform().get());
+        assertEquals(version4, tester.instance(default3.id()).change().platform().get());
     }
 
     @Test
@@ -271,18 +279,18 @@ public class UpgraderTest {
         assertEquals("No applications: Nothing to do", 0, tester.buildService().jobs().size());
 
         // Setup applications
-        Instance canary0  = tester.createAndDeploy("canary0", 1, "canary");
-        Instance canary1  = tester.createAndDeploy("canary1", 2, "canary");
-        Instance default0 = tester.createAndDeploy("default0", 3, "default");
-        Instance default1 = tester.createAndDeploy("default1", 4, "default");
-        Instance default2 = tester.createAndDeploy("default2", 5, "default");
-        Instance default3 = tester.createAndDeploy("default3", 6, "default");
-        Instance default4 = tester.createAndDeploy("default4", 7, "default");
-        Instance default5 = tester.createAndDeploy("default5", 8, "default");
-        Instance default6 = tester.createAndDeploy("default6", 9, "default");
-        Instance default7 = tester.createAndDeploy("default7", 10, "default");
-        Instance default8 = tester.createAndDeploy("default8", 11, "default");
-        Instance default9 = tester.createAndDeploy("default9", 12, "default");
+        Application canary0  = tester.createAndDeploy("canary0", 1, "canary");
+        Application canary1  = tester.createAndDeploy("canary1", 2, "canary");
+        Application default0 = tester.createAndDeploy("default0", 3, "default");
+        Application default1 = tester.createAndDeploy("default1", 4, "default");
+        Application default2 = tester.createAndDeploy("default2", 5, "default");
+        Application default3 = tester.createAndDeploy("default3", 6, "default");
+        Application default4 = tester.createAndDeploy("default4", 7, "default");
+        Application default5 = tester.createAndDeploy("default5", 8, "default");
+        Application default6 = tester.createAndDeploy("default6", 9, "default");
+        Application default7 = tester.createAndDeploy("default7", 10, "default");
+        Application default8 = tester.createAndDeploy("default8", 11, "default");
+        Application default9 = tester.createAndDeploy("default9", 12, "default");
 
         tester.upgrader().maintain();
         tester.triggerUntilQuiescence();
@@ -338,11 +346,12 @@ public class UpgraderTest {
         Version version = Version.fromString("6.2");
         tester.upgradeSystem(version);
 
-        Instance app = tester.createApplication("app1", "tenant1", 1, 11L);
+        Application app = tester.createApplication("app1", "tenant1", 1, 11L);
+        Instance instance = tester.instance(app.id());
         tester.jobCompletion(component).application(app).uploadArtifact(applicationPackage).submit();
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsEast3);
 
         tester.upgrader().maintain();
         tester.triggerUntilQuiescence();
@@ -357,12 +366,12 @@ public class UpgraderTest {
         tester.triggerUntilQuiescence();
 
         // system-test completes successfully
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
 
         // staging-test fails and failure is recorded
-        tester.deployAndNotify(app, applicationPackage, false, stagingTest);
-        assertTrue("Failure is recorded", tester.application(app.id()).deploymentJobs().hasFailures());
-        assertTrue("Application has pending change", tester.application(app.id()).change().hasTargets());
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, stagingTest);
+        assertTrue("Failure is recorded", tester.instance(app.id()).deploymentJobs().hasFailures());
+        assertTrue("Application has pending change", tester.instance(app.id()).change().hasTargets());
 
         // New version is released
         version = Version.fromString("6.4");
@@ -373,7 +382,7 @@ public class UpgraderTest {
         tester.upgrader().maintain();
         tester.triggerUntilQuiescence();
         tester.jobCompletion(stagingTest).application(app).unsuccessful().submit();
-        assertTrue("Application still has failures", tester.application(app.id()).deploymentJobs().hasFailures());
+        assertTrue("Application still has failures", tester.instance(app.id()).deploymentJobs().hasFailures());
         assertEquals(2, tester.buildService().jobs().size());
 
         // Upgrader runs again, nothing happens as test jobs are already running.
@@ -389,13 +398,13 @@ public class UpgraderTest {
         tester.upgradeSystem(version);
 
         // Setup applications
-        Instance canary0 = tester.createAndDeploy("canary0", 1, "canary");
-        Instance canary1 = tester.createAndDeploy("canary1", 2, "canary");
-        Instance default0 = tester.createAndDeploy("default0", 3, "default");
-        Instance default1 = tester.createAndDeploy("default1", 4, "default");
-        Instance default2 = tester.createAndDeploy("default2", 5, "default");
-        Instance default3 = tester.createAndDeploy("default3", 6, "default");
-        Instance default4 = tester.createAndDeploy("default4", 7, "default");
+        Application canary0 = tester.createAndDeploy("canary0", 1, "canary");
+        Application canary1 = tester.createAndDeploy("canary1", 2, "canary");
+        Application default0 = tester.createAndDeploy("default0", 3, "default");
+        Application default1 = tester.createAndDeploy("default1", 4, "default");
+        Application default2 = tester.createAndDeploy("default2", 5, "default");
+        Application default3 = tester.createAndDeploy("default3", 6, "default");
+        Application default4 = tester.createAndDeploy("default4", 7, "default");
 
         // New version is released
         version = Version.fromString("6.3");
@@ -455,13 +464,13 @@ public class UpgraderTest {
         tester.upgradeSystem(v0);
 
         // Setup applications on V0
-        Instance canary0 = tester.createAndDeploy("canary0", 1, "canary");
-        Instance canary1 = tester.createAndDeploy("canary1", 2, "canary");
-        Instance default0 = tester.createAndDeploy("default0", 3, "default");
-        Instance default1 = tester.createAndDeploy("default1", 4, "default");
-        Instance default2 = tester.createAndDeploy("default2", 5, "default");
-        Instance default3 = tester.createAndDeploy("default3", 6, "default");
-        Instance default4 = tester.createAndDeploy("default4", 7, "default");
+        Application canary0 = tester.createAndDeploy("canary0", 1, "canary");
+        Application canary1 = tester.createAndDeploy("canary1", 2, "canary");
+        Application default0 = tester.createAndDeploy("default0", 3, "default");
+        Application default1 = tester.createAndDeploy("default1", 4, "default");
+        Application default2 = tester.createAndDeploy("default2", 5, "default");
+        Application default3 = tester.createAndDeploy("default3", 6, "default");
+        Application default4 = tester.createAndDeploy("default4", 7, "default");
 
         // V1 is released
         Version v1 = Version.fromString("6.3");
@@ -501,7 +510,7 @@ public class UpgraderTest {
         tester.upgrader().maintain();
         tester.triggerUntilQuiescence();
         assertEquals("Upgrade scheduled for remaining apps", 10, tester.buildService().jobs().size());
-        assertEquals("default4 is still upgrading to 5.1", v1, tester.application(default4.id()).change().platform().get());
+        assertEquals("default4 is still upgrading to 5.1", v1, tester.instance(default4.id()).change().platform().get());
 
         // 4/5 applications fail (in the last prod zone) and lowers confidence
         tester.completeUpgradeWithError(default0, v2, "default", productionUsEast3);
@@ -511,8 +520,8 @@ public class UpgraderTest {
         tester.upgradeSystem(v2);
         assertEquals(VespaVersion.Confidence.broken, tester.controller().versionStatus().systemVersion().get().confidence());
 
-        assertEquals(v2, tester.application("default0").deployments().get(ZoneId.from("prod.us-west-1")).version());
-        assertEquals(v0, tester.application("default0").deployments().get(ZoneId.from("prod.us-east-3")).version());
+        assertEquals(v2, tester.instance("default0").deployments().get(ZoneId.from("prod.us-west-1")).version());
+        assertEquals(v0, tester.instance("default0").deployments().get(ZoneId.from("prod.us-east-3")).version());
         tester.upgrader().maintain();
         tester.buildService().clear();
         tester.triggerUntilQuiescence();
@@ -520,16 +529,16 @@ public class UpgraderTest {
         assertEquals("Upgrade to 5.1 scheduled for apps not completely on 5.1 or 5.2", 10, tester.buildService().jobs().size());
 
         // The tester code for completing upgrades does not handle this scenario, so we trigger each step manually (for one app)
-        tester.deployAndNotify(tester.application("default0"), "default", true, systemTest);
-        tester.deployAndNotify(tester.application("default0"), "default", true, stagingTest);
+        tester.deployAndNotify(tester.instance("default0").id(), DeploymentTester.applicationPackage("default"), true, systemTest);
+        tester.deployAndNotify(tester.instance("default0").id(), DeploymentTester.applicationPackage("default"), true, stagingTest);
         // prod zone on 5.2 (usWest1) is skipped, but we still trigger the next zone from triggerReadyJobs:
-        tester.deployAndNotify(tester.application("default0"), "default", true, productionUsEast3);
+        tester.deployAndNotify(tester.instance("default0").id(), DeploymentTester.applicationPackage("default"), true, productionUsEast3);
 
         // Resulting state:
-        assertEquals(v2, tester.application("default0").deployments().get(ZoneId.from("prod.us-west-1")).version());
+        assertEquals(v2, tester.instance("default0").deployments().get(ZoneId.from("prod.us-west-1")).version());
         assertEquals("Last zone is upgraded to v1",
-                     v1, tester.application("default0").deployments().get(ZoneId.from("prod.us-east-3")).version());
-        assertFalse(tester.application("default0").change().hasTargets());
+                     v1, tester.instance("default0").deployments().get(ZoneId.from("prod.us-east-3")).version());
+        assertFalse(tester.instance("default0").change().hasTargets());
     }
 
     @Test
@@ -542,13 +551,13 @@ public class UpgraderTest {
         ApplicationPackage defaultPolicy = DeploymentTester.applicationPackage("default");
 
         // Setup applications
-        Instance canary0 = tester.createAndDeploy("canary0", 1, canaryPolicy);
-        Instance canary1 = tester.createAndDeploy("canary1", 2, canaryPolicy);
-        Instance default0 = tester.createAndDeploy("default0", 3, defaultPolicy);
-        Instance default1 = tester.createAndDeploy("default1", 4, defaultPolicy);
-        Instance default2 = tester.createAndDeploy("default2", 5, defaultPolicy);
-        Instance default3 = tester.createAndDeploy("default3", 6, defaultPolicy);
-        Instance default4 = tester.createAndDeploy("default4", 7, defaultPolicy);
+        Application canary0 = tester.createAndDeploy("canary0", 1, canaryPolicy);
+        Application canary1 = tester.createAndDeploy("canary1", 2, canaryPolicy);
+        Application default0 = tester.createAndDeploy("default0", 3, defaultPolicy);
+        Application default1 = tester.createAndDeploy("default1", 4, defaultPolicy);
+        Application default2 = tester.createAndDeploy("default2", 5, defaultPolicy);
+        Application default3 = tester.createAndDeploy("default3", 6, defaultPolicy);
+        Application default4 = tester.createAndDeploy("default4", 7, defaultPolicy);
 
         // New version is released
         version = Version.fromString("6.3");
@@ -600,7 +609,7 @@ public class UpgraderTest {
                 .region("us-west-1")
                 .build();
 
-        Instance app = tester.createAndDeploy("app1", 1, applicationPackage);
+        Application app = tester.createAndDeploy("app1", 1, applicationPackage);
 
         // New version is released
         version = Version.fromString("6.3");
@@ -643,7 +652,8 @@ public class UpgraderTest {
                 .region("us-east-3")
                 .build();
 
-        Instance app = tester.createAndDeploy("app1", 1, applicationPackage);
+        Application app = tester.createAndDeploy("app1", 1, applicationPackage);
+        Instance instance = tester.instance(app.id());
 
         // New version is released
         version = Version.fromString("6.3");
@@ -652,14 +662,14 @@ public class UpgraderTest {
         // Application upgrade starts
         tester.upgrader().maintain();
         tester.triggerUntilQuiescence();
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
         tester.clock().advance(Duration.ofHours(1)); // Entering block window after prod job is triggered
-        tester.deployAndNotify(app, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsWest1);
         assertEquals(1, tester.buildService().jobs().size()); // Next job triggered because upgrade is already rolling out.
 
-        tester.deployAndNotify(app, applicationPackage, true, productionUsCentral1);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsEast3);
         assertTrue("All jobs consumed", tester.buildService().jobs().isEmpty());
     }
 
@@ -680,7 +690,8 @@ public class UpgraderTest {
                 .region("us-east-3")
                 .build();
 
-        Instance app = tester.createAndDeploy("app1", 1, applicationPackage);
+        Application app = tester.createAndDeploy("app1", 1, applicationPackage);
+        Instance instance = tester.instance(app.id());
 
         // New version is released
         version = Version.fromString("6.3");
@@ -689,24 +700,25 @@ public class UpgraderTest {
         // Application upgrade starts
         tester.upgrader().maintain();
         tester.triggerUntilQuiescence();
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
         tester.clock().advance(Duration.ofHours(1)); // Entering block window after prod job is triggered
-        tester.deployAndNotify(app, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsWest1);
         assertEquals(1, tester.buildService().jobs().size()); // Next job triggered, as upgrade is already in progress.
-        tester.deployAndNotify(app, applicationPackage, false, productionUsCentral1); // us-central-1 fails, permitting a new revision.
+        // us-central-1 fails, permitting a new revision.
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, productionUsCentral1);
 
         // A new revision is submitted and starts rolling out.
         tester.jobCompletion(component).application(app).nextBuildNumber().uploadArtifact(applicationPackage).submit();
 
         // us-central-1 fails again, and isn't re-triggered, because the target is now a revision instead.
-        tester.deployAndNotify(app, applicationPackage, false, productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, productionUsCentral1);
         assertEquals(2, tester.buildService().jobs().size());
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsWest1);
         // us-central-1 has an older version, and needs a new staging test to begin.
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
 
         // A new version is also released, cancelling the upgrade, since it is failing on a now outdated version.
         tester.clock().advance(Duration.ofDays(1));
@@ -716,10 +728,10 @@ public class UpgraderTest {
         tester.triggerUntilQuiescence();
 
         // us-central-1 succeeds upgrade to 5.1, with the revision, but us-east-3 wants to proceed with only the revision change.
-        tester.deployAndNotify(app, applicationPackage, true, productionUsCentral1);
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsEast3);
         assertEquals(Collections.emptyList(), tester.buildService().jobs());
 
         // Monday morning: We are not blocked, and the new version rolls out to all zones.
@@ -727,12 +739,12 @@ public class UpgraderTest {
         tester.clock().advance(Duration.ofHours(17)); // Monday, 10:00
         tester.upgrader().maintain();
         tester.triggerUntilQuiescence();
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsWest1);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsCentral1);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsEast3);
         assertTrue("All jobs consumed", tester.buildService().jobs().isEmpty());
 
         // App is completely upgraded to the latest version
@@ -758,13 +770,13 @@ public class UpgraderTest {
                 .build();
 
         // Setup applications
-        Instance canary0 = tester.createAndDeploy("canary0", 1, canaryApplicationPackage);
-        Instance canary1 = tester.createAndDeploy("canary1", 2, canaryApplicationPackage);
-        Instance default0 = tester.createAndDeploy("default0", 3, defaultApplicationPackage);
-        Instance default1 = tester.createAndDeploy("default1", 4, defaultApplicationPackage);
-        Instance default2 = tester.createAndDeploy("default2", 5, defaultApplicationPackage);
-        Instance default3 = tester.createAndDeploy("default3", 6, defaultApplicationPackage);
-        Instance default4 = tester.createAndDeploy("default4", 7, defaultApplicationPackage);
+        Application canary0 = tester.createAndDeploy("canary0", 1, canaryApplicationPackage);
+        Application canary1 = tester.createAndDeploy("canary1", 2, canaryApplicationPackage);
+        Application default0 = tester.createAndDeploy("default0", 3, defaultApplicationPackage);
+        Application default1 = tester.createAndDeploy("default1", 4, defaultApplicationPackage);
+        Application default2 = tester.createAndDeploy("default2", 5, defaultApplicationPackage);
+        Application default3 = tester.createAndDeploy("default3", 6, defaultApplicationPackage);
+        Application default4 = tester.createAndDeploy("default4", 7, defaultApplicationPackage);
 
         assertEquals(version, default0.oldestDeployedPlatform().get());
 
@@ -838,10 +850,10 @@ public class UpgraderTest {
         tester.completeUpgrade(default2, version, defaultApplicationPackageV2);
         tester.completeUpgrade(default3, version, defaultApplicationPackageV2);
 
-        assertEquals(version, tester.application(default0.id()).oldestDeployedPlatform().get());
-        assertEquals(version, tester.application(default1.id()).oldestDeployedPlatform().get());
-        assertEquals(version, tester.application(default2.id()).oldestDeployedPlatform().get());
-        assertEquals(version, tester.application(default3.id()).oldestDeployedPlatform().get());
+        assertEquals(version, tester.instance(default0.id()).oldestDeployedPlatform().get());
+        assertEquals(version, tester.instance(default1.id()).oldestDeployedPlatform().get());
+        assertEquals(version, tester.instance(default2.id()).oldestDeployedPlatform().get());
+        assertEquals(version, tester.instance(default3.id()).oldestDeployedPlatform().get());
     }
 
     @Test
@@ -857,16 +869,16 @@ public class UpgraderTest {
         upgrader.setUpgradesPerMinute(0.2);
 
         // Setup applications
-        Instance canary0 = tester.createAndDeploy("canary0", 1, "canary");
-        Instance canary1 = tester.createAndDeploy("canary1", 2, "canary");
-        Instance default0 = tester.createAndDeploy("default0", 3, "default");
-        Instance default1 = tester.createAndDeploy("default1", 4, "default");
-        Instance default2 = tester.createAndDeploy("default2", 5, "default");
-        Instance default3 = tester.createAndDeploy("default3", 6, "default");
+        Application canary0 = tester.createAndDeploy("canary0", 1, "canary");
+        Application canary1 = tester.createAndDeploy("canary1", 2, "canary");
+        Application default0 = tester.createAndDeploy("default0", 3, "default");
+        Application default1 = tester.createAndDeploy("default1", 4, "default");
+        Application default2 = tester.createAndDeploy("default2", 5, "default");
+        Application default3 = tester.createAndDeploy("default3", 6, "default");
 
         // Dev deployment which should be ignored
-        Instance dev0 = tester.createApplication("dev0", "tenant1", 7, 1L);
-        tester.controllerTester().deploy(dev0, ZoneId.from(Environment.dev, RegionName.from("dev-region")));
+        Application dev0 = tester.createApplication("dev0", "tenant1", 7, 1L);
+        tester.controllerTester().deploy(dev0.id(), ZoneId.from(Environment.dev, RegionName.from("dev-region")));
 
         // New version is released and canaries upgrade
         version = Version.fromString("6.3");
@@ -910,8 +922,8 @@ public class UpgraderTest {
                                                                 .build();
 
         // Setup applications
-        Instance canary0 = tester.createAndDeploy("canary0", 1, "canary");
-        Instance default0 = tester.createAndDeploy("default0", 2, version6ApplicationPackage);
+        Application canary0 = tester.createAndDeploy("canary0", 1, "canary");
+        Application default0 = tester.createAndDeploy("default0", 2, version6ApplicationPackage);
 
         // New major version is released
         version = Version.fromString("7.0");
@@ -944,8 +956,8 @@ public class UpgraderTest {
                                                                 .build();
 
         // Setup applications
-        Instance canary0 = tester.createAndDeploy("canary0", 1, "canary");
-        Instance default0 = tester.createAndDeploy("default0", 2, default0ApplicationPackage);
+        Application canary0 = tester.createAndDeploy("canary0", 1, "canary");
+        Application default0 = tester.createAndDeploy("default0", 2, default0ApplicationPackage);
         tester.applications().lockOrThrow(default0.id(), a -> tester.applications().store(a.withMajorVersion(6)));
         assertEquals(OptionalInt.of(6), tester.applications().get(default0.id()).get().majorVersion());
 
@@ -987,9 +999,9 @@ public class UpgraderTest {
                                                                 .build();
 
         // Setup applications
-        Instance canary0 = tester.createAndDeploy("canary", 1, version7CanaryApplicationPackage);
-        Instance default0 = tester.createAndDeploy("default0", 2, version7DefaultApplicationPackage);
-        Instance default1 = tester.createAndDeploy("default1", 3, "default");
+        Application canary0 = tester.createAndDeploy("canary", 1, version7CanaryApplicationPackage);
+        Application default0 = tester.createAndDeploy("default0", 2, version7DefaultApplicationPackage);
+        Application default1 = tester.createAndDeploy("default1", 3, "default");
 
         // New major version is released, but we don't want to upgrade to it yet
         tester.upgrader().setTargetMajorVersion(Optional.of(6));
@@ -1034,7 +1046,8 @@ public class UpgraderTest {
                 .region("us-west-1")
                 .build();
 
-        Instance app = tester.createAndDeploy("app1", 1, applicationPackage);
+        Application app = tester.createAndDeploy("app1", 1, applicationPackage);
+        Instance instance = tester.instance(app.id());
 
         // New version is released
         version = Version.fromString("6.3");
@@ -1042,9 +1055,9 @@ public class UpgraderTest {
         tester.upgrader().maintain();
         tester.triggerUntilQuiescence();
 
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app, applicationPackage, false, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), false, productionUsWest1);
 
         // New application change
         tester.jobCompletion(component).application(app).nextBuildNumber().uploadArtifact(applicationPackage).submit();
@@ -1057,14 +1070,14 @@ public class UpgraderTest {
                    app.change().application().get().id().equals(applicationVersion));
 
         // Deployment completes
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
         tester.jobCompletion(productionUsWest1).application(app).unsuccessful().submit();
-        tester.deployAndNotify(app, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsWest1);
         assertTrue("All jobs consumed", tester.buildService().jobs().isEmpty());
 
-        app = tester.application(app.id());
-        for (Deployment deployment : app.deployments().values()) {
+        instance = tester.instance(app.id());
+        for (Deployment deployment : instance.deployments().values()) {
             assertEquals(version, deployment.version());
             assertEquals(applicationVersion, deployment.applicationVersion().id());
         }
@@ -1087,17 +1100,18 @@ public class UpgraderTest {
                 .region("us-east-3")
                 .build();
 
-        Instance app = tester.createAndDeploy("app1", 1, applicationPackage);
+        Application app = tester.createAndDeploy("app1", 1, applicationPackage);
+        Instance instance = tester.instance(app.id());
 
         tester.jobCompletion(component).application(app).nextBuildNumber().uploadArtifact(applicationPackage).submit();
 
         // Application upgrade starts.
         tester.upgrader().maintain();
         tester.triggerUntilQuiescence();
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
         tester.clock().advance(Duration.ofHours(1)); // Entering block window after prod job is triggered.
-        tester.deployAndNotify(app, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsWest1);
         assertEquals(1, tester.buildService().jobs().size()); // Next job triggered in spite of block, because it is already rolling out.
 
         // New version is released, but upgrades won't start since there's already a revision rolling out.
@@ -1106,18 +1120,18 @@ public class UpgraderTest {
         tester.triggerUntilQuiescence();
         assertEquals(1, tester.buildService().jobs().size()); // Still just the revision upgrade.
 
-        tester.deployAndNotify(app, applicationPackage, true, productionUsCentral1);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsEast3);
         assertEquals(Collections.emptyList(), tester.buildService().jobs()); // No jobs left.
 
         // Upgrade may start, now that revision is rolled out.
         tester.upgrader().maintain();
         tester.readyJobTrigger().maintain();
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsWest1);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsCentral1);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsEast3);
         assertTrue("All jobs consumed", tester.buildService().jobs().isEmpty());
     }
 
@@ -1139,17 +1153,18 @@ public class UpgraderTest {
                 .region("us-east-3")
                 .build();
 
-        Instance app = tester.createAndDeploy("app1", 1, applicationPackage);
+        Application app = tester.createAndDeploy("app1", 1, applicationPackage);
+        Instance instance = tester.instance(app.id());
 
         tester.jobCompletion(component).application(app).nextBuildNumber().uploadArtifact(applicationPackage).submit();
 
         // Application revision starts rolling out.
         tester.upgrader().maintain();
         tester.triggerUntilQuiescence();
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
         tester.clock().advance(Duration.ofHours(1)); // Entering block window after prod job is triggered.
-        tester.deployAndNotify(app, applicationPackage, true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsWest1);
         assertEquals(1, tester.buildService().jobs().size());
 
         // New revision is submitted, but is stored as outstanding, since the upgrade is proceeding in good fashion.
@@ -1157,23 +1172,23 @@ public class UpgraderTest {
         tester.triggerUntilQuiescence();
         assertEquals(3, tester.buildService().jobs().size()); // Just the running upgrade, and tests for the new revision.
 
-        tester.deployAndNotify(app, applicationPackage, true, systemTest);
-        tester.deployAndNotify(app, applicationPackage, true, stagingTest);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsCentral1);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsEast3);
         assertEquals(Collections.emptyList(), tester.buildService().jobs()); // No jobs left.
 
         tester.outstandingChangeDeployer().run();
-        assertFalse(tester.application(app.id()).change().hasTargets());
+        assertFalse(tester.instance(app.id()).change().hasTargets());
         tester.clock().advance(Duration.ofHours(2));
 
         tester.outstandingChangeDeployer().run();
-        assertTrue(tester.application(app.id()).change().hasTargets());
+        assertTrue(tester.instance(app.id()).change().hasTargets());
         tester.readyJobTrigger().run();
-        tester.deployAndNotify(app, applicationPackage, true, productionUsWest1);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsCentral1);
-        tester.deployAndNotify(app, applicationPackage, true, productionUsEast3);
-        assertFalse(tester.application(app.id()).change().hasTargets());
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.of(applicationPackage), true, productionUsEast3);
+        assertFalse(tester.instance(app.id()).change().hasTargets());
     }
 
     @Test
@@ -1183,61 +1198,62 @@ public class UpgraderTest {
         tester.upgradeSystem(version0);
 
         // Create an application with pinned platform version.
-        Instance instance = tester.createApplication("application", "tenant", 2, 3);
+        Application application = tester.createApplication("application", "tenant", 2, 3);
+        Instance instance = tester.instance(application.id());
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder().environment(Environment.prod)
                                                                                .region("us-east-3")
                                                                                .region("us-west-1")
                                                                                .build();
-        tester.deploymentTrigger().forceChange(instance.id(), Change.empty().withPin());
+        tester.deploymentTrigger().forceChange(application.id(), Change.empty().withPin());
 
-        tester.deployCompletely(instance, applicationPackage);
-        assertFalse(tester.application(instance.id()).change().hasTargets());
-        assertTrue(tester.application(instance.id()).change().isPinned());
-        assertEquals(2, tester.application(instance.id()).deployments().size());
+        tester.deployCompletely(application, applicationPackage);
+        assertFalse(tester.instance(application.id()).change().hasTargets());
+        assertTrue(tester.instance(application.id()).change().isPinned());
+        assertEquals(2, tester.instance(application.id()).deployments().size());
 
         // Application does not upgrade.
         Version version1 = Version.fromString("6.3");
         tester.upgradeSystem(version1);
         tester.upgrader().maintain();
-        assertFalse(tester.application(instance.id()).change().hasTargets());
-        assertTrue(tester.application(instance.id()).change().isPinned());
+        assertFalse(tester.instance(application.id()).change().hasTargets());
+        assertTrue(tester.instance(application.id()).change().isPinned());
 
         // New application package is deployed.
-        tester.deployCompletely(instance, applicationPackage, BuildJob.defaultBuildNumber + 1);
-        assertFalse(tester.application(instance.id()).change().hasTargets());
-        assertTrue(tester.application(instance.id()).change().isPinned());
+        tester.deployCompletely(application, applicationPackage, BuildJob.defaultBuildNumber + 1);
+        assertFalse(tester.instance(application.id()).change().hasTargets());
+        assertTrue(tester.instance(application.id()).change().isPinned());
 
         // Application upgrades to new version when pin is removed.
-        tester.deploymentTrigger().cancelChange(instance.id(), PIN);
+        tester.deploymentTrigger().cancelChange(application.id(), PIN);
         tester.upgrader().maintain();
-        assertTrue(tester.application(instance.id()).change().hasTargets());
-        assertFalse(tester.application(instance.id()).change().isPinned());
+        assertTrue(tester.instance(application.id()).change().hasTargets());
+        assertFalse(tester.instance(application.id()).change().isPinned());
 
         // Application is pinned to new version, and upgrade is therefore not cancelled, even though confidence is broken.
-        tester.deploymentTrigger().forceChange(instance.id(), Change.empty().withPin());
+        tester.deploymentTrigger().forceChange(application.id(), Change.empty().withPin());
         tester.upgrader().maintain();
         tester.readyJobTrigger().maintain();
-        assertEquals(version1, tester.application(instance.id()).change().platform().get());
+        assertEquals(version1, tester.instance(application.id()).change().platform().get());
 
         // Application fails upgrade after one zone is complete, and is pinned again to the old version.
-        tester.deployAndNotify(instance, true, systemTest);
-        tester.deployAndNotify(instance, true, stagingTest);
-        tester.deployAndNotify(instance, true, productionUsEast3);
-        tester.deploy(productionUsWest1, instance, Optional.empty(), false);
-        tester.deployAndNotify(instance, false, productionUsWest1);
-        tester.deploymentTrigger().cancelChange(instance.id(), ALL);
-        tester.deploymentTrigger().forceChange(instance.id(), Change.of(version0).withPin());
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionUsEast3);
+        tester.deploy(productionUsWest1, instance.id(), Optional.empty(), false);
+        tester.deployAndNotify(instance.id(), Optional.empty(), false, productionUsWest1);
+        tester.deploymentTrigger().cancelChange(application.id(), ALL);
+        tester.deploymentTrigger().forceChange(application.id(), Change.of(version0).withPin());
         tester.buildService().clear();
-        assertEquals(version0, tester.application(instance.id()).change().platform().get());
+        assertEquals(version0, tester.instance(application.id()).change().platform().get());
 
         // Application downgrades to pinned version.
         tester.readyJobTrigger().maintain();
-        tester.deployAndNotify(instance, true, systemTest);
-        tester.deployAndNotify(instance, true, stagingTest);
-        tester.deployAndNotify(instance, true, productionUsEast3);
-        assertTrue(tester.application(instance.id()).change().hasTargets());
-        tester.deployAndNotify(instance, true, productionUsWest1);
-        assertFalse(tester.application(instance.id()).change().hasTargets());
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionUsEast3);
+        assertTrue(tester.instance(application.id()).change().hasTargets());
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionUsWest1);
+        assertFalse(tester.instance(application.id()).change().hasTargets());
     }
 
     @Test
@@ -1250,8 +1266,8 @@ public class UpgraderTest {
         tester.upgrader().setTargetMajorVersion(Optional.of(6));
 
         // All applications deploy on current version
-        Instance app1 = tester.createAndDeploy("app1", 1, "default");
-        Instance app2 = tester.createAndDeploy("app2", 1, "default");
+        Application app1 = tester.createAndDeploy("app1", 1, "default");
+        Application app2 = tester.createAndDeploy("app2", 1, "default");
 
         // Keep app 1 on current version
         tester.controller().applications().lockIfPresent(app1.id(), app -> tester.controller().applications().store(app.withChange(app.get().change().withPin())));
@@ -1283,8 +1299,9 @@ public class UpgraderTest {
     @Test
     public void testsEachUpgradeCombinationWithFailingDeployments() {
         DeploymentTester tester = new DeploymentTester();
-        Instance instance = tester.createApplication("app1", "tenant1", 1, 1L);
-        Supplier<Instance> app = () -> tester.application(instance.id());
+        Application application = tester.createApplication("app1", "tenant1", 1, 1L);
+        Instance instance = tester.instance(application.id());
+        Supplier<Instance> app = () -> tester.instance(application.id());
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-central-1")
@@ -1294,22 +1311,22 @@ public class UpgraderTest {
 
         // Application deploys on system version
         Version v1 = Version.fromString("6.1");
-        tester.deployCompletely(instance, applicationPackage);
+        tester.deployCompletely(application, applicationPackage);
 
         // Next version is released and 2/3 deployments upgrade
         Version v2 = Version.fromString("6.2");
         tester.upgradeSystem(v2);
         tester.upgrader().maintain();
         assertEquals(Change.of(v2), app.get().change());
-        tester.deployAndNotify(instance, true, systemTest);
-        tester.deployAndNotify(instance, true, stagingTest);
-        tester.deployAndNotify(instance, true, productionUsCentral1);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionUsCentral1);
 
         // While second deployment completes upgrade, version confidence becomes broken and upgrade is cancelled
         tester.upgrader().overrideConfidence(v2, VespaVersion.Confidence.broken);
         tester.computeVersionStatus();
         tester.upgrader().maintain();
-        tester.deployAndNotify(instance, true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionUsWest1);
         assertTrue(app.get().change().isEmpty());
 
         // Next version is released
@@ -1317,21 +1334,21 @@ public class UpgraderTest {
         tester.upgradeSystem(v3);
         tester.upgrader().maintain();
         assertEquals(Change.of(v3), app.get().change());
-        tester.deployAndNotify(instance, true, systemTest);
-        tester.deployAndNotify(instance, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, systemTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
 
         // First deployment starts upgrading
-        tester.deploy(productionUsCentral1, instance, applicationPackage);
+        tester.deploy(productionUsCentral1, instance.id(), applicationPackage);
 
         // Before deployment completes, v1->v3 combination is tested as us-east-3 is still on v1
         tester.readyJobTrigger().maintain();
-        tester.deployAndNotify(instance, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
         assertEquals(v1, app.get().deploymentJobs().jobStatus().get(stagingTest).lastSuccess().get().sourcePlatform().get());
         assertEquals(v3, app.get().deploymentJobs().jobStatus().get(stagingTest).lastSuccess().get().platform());
 
         // First deployment fails and then successfully upgrades to v3
-        tester.jobCompletion(productionUsCentral1).application(instance).unsuccessful().submit();
-        tester.jobCompletion(productionUsCentral1).application(instance).submit();
+        tester.jobCompletion(productionUsCentral1).application(application).unsuccessful().submit();
+        tester.jobCompletion(productionUsCentral1).application(application).submit();
 
         // Deployments are now on 3 versions
         assertEquals(v3, app.get().deployments().get(productionUsCentral1.zone(main)).version());
@@ -1342,19 +1359,19 @@ public class UpgraderTest {
         tester.readyJobTrigger().maintain();
         assertEquals(v2, app.get().deploymentJobs().jobStatus().get(stagingTest).lastTriggered().get().sourcePlatform().get());
         assertEquals(v3, app.get().deploymentJobs().jobStatus().get(stagingTest).lastTriggered().get().platform());
-        tester.deployAndNotify(instance, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
 
         // Second deployment upgrades
-        tester.deployAndNotify(instance, true, productionUsWest1);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionUsWest1);
 
         // ... now we have to test v1->v3 again :(
         tester.readyJobTrigger().maintain();
         assertEquals(v1, app.get().deploymentJobs().jobStatus().get(stagingTest).lastTriggered().get().sourcePlatform().get());
         assertEquals(v3, app.get().deploymentJobs().jobStatus().get(stagingTest).lastTriggered().get().platform());
-        tester.deployAndNotify(instance, true, stagingTest);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, stagingTest);
 
         // Upgrade completes
-        tester.deployAndNotify(instance, true, productionUsEast3);
+        tester.deployAndNotify(instance.id(), Optional.empty(), true, productionUsEast3);
         assertTrue("Upgrade complete", app.get().change().isEmpty());
     }
 
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/ContainerControllerTester.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/ContainerControllerTester.java
index b8a0610bedd..290969623d8 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/ContainerControllerTester.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/ContainerControllerTester.java
@@ -11,7 +11,7 @@ import com.yahoo.vespa.athenz.api.AthenzDomain;
 import com.yahoo.vespa.athenz.api.AthenzPrincipal;
 import com.yahoo.vespa.athenz.api.AthenzUser;
 import com.yahoo.vespa.athenz.api.OktaAccessToken;
-import com.yahoo.vespa.hosted.controller.Instance;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Controller;
 import com.yahoo.vespa.hosted.controller.api.application.v4.model.DeployOptions;
 import com.yahoo.vespa.hosted.controller.api.identifiers.Property;
@@ -64,11 +64,11 @@ public class ContainerControllerTester {
     /** Returns the wrapped generic container tester */
     public ContainerTester containerTester() { return containerTester; }
 
-    public Instance createApplication() {
+    public Application createApplication() {
         return createApplication("domain1","tenant1", "application1", "default");
     }
 
-    public Instance createApplication(String athensDomain, String tenant, String application, String instance) {
+    public Application createApplication(String athensDomain, String tenant, String application, String instance) {
         AthenzDomain domain1 = addTenantAthenzDomain(athensDomain, "user");
         AthenzPrincipal user = new AthenzPrincipal(new AthenzUser("user"));
         AthenzCredentials credentials = new AthenzCredentials(user, domain1, new OktaAccessToken("okta-token"));
@@ -82,15 +82,14 @@ public class ContainerControllerTester {
         return controller().applications().createApplication(app, Optional.of(credentials));
     }
 
-    public Instance deploy(Instance instance, ApplicationPackage applicationPackage, ZoneId zone) {
-        controller().applications().deploy(instance.id(), zone, Optional.of(applicationPackage),
+    public void deploy(ApplicationId id, ApplicationPackage applicationPackage, ZoneId zone) {
+        controller().applications().deploy(id, zone, Optional.of(applicationPackage),
                                            new DeployOptions(false, Optional.empty(), false, false));
-        return instance;
     }
 
-    public void deployCompletely(Instance instance, ApplicationPackage applicationPackage, long projectId,
+    public void deployCompletely(Application application, ApplicationPackage applicationPackage, long projectId,
                                  boolean failStaging) {
-        jobCompletion(JobType.component).application(instance)
+        jobCompletion(JobType.component).application(application)
                                         .projectId(projectId)
                                         .uploadArtifact(applicationPackage)
                                         .submit();
@@ -99,14 +98,14 @@ public class ContainerControllerTester {
         for (var job : steps.jobs()) {
             if (!succeeding) return;
             var zone = job.zone(controller().system());
-            deploy(instance, applicationPackage, zone);
+            deploy(application.id(), applicationPackage, zone);
             if (failStaging && zone.environment() == Environment.staging) {
                 succeeding = false;
             }
             if (zone.environment().isTest()) {
-                controller().applications().deactivate(instance.id(), zone);
+                controller().applications().deactivate(application.id(), zone);
             }
-            jobCompletion(job).application(instance).success(succeeding).projectId(projectId).submit();
+            jobCompletion(job).application(application).success(succeeding).projectId(projectId).submit();
         }
     }
 
@@ -128,13 +127,13 @@ public class ContainerControllerTester {
     /*
      * Authorize action on tenantDomain/application for a given screwdriverId
      */
-    public void authorize(AthenzDomain tenantDomain, ScrewdriverId screwdriverId, ApplicationAction action, Instance instance) {
+    public void authorize(AthenzDomain tenantDomain, ScrewdriverId screwdriverId, ApplicationAction action, ApplicationId id) {
         AthenzClientFactoryMock mock = (AthenzClientFactoryMock) containerTester.container().components()
                 .getComponent(AthenzClientFactoryMock.class.getName());
 
         mock.getSetup()
                 .domains.get(tenantDomain)
-                .applications.get(new com.yahoo.vespa.hosted.controller.api.identifiers.ApplicationId(instance.id().application().value()))
+                .applications.get(new com.yahoo.vespa.hosted.controller.api.identifiers.ApplicationId(id.application().value()))
                 .addRoleMember(action, HostedAthenzIdentities.from(screwdriverId));
     }
 
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/application/ApplicationApiTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/application/ApplicationApiTest.java
index b2494be65b1..474944432fb 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/application/ApplicationApiTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/application/ApplicationApiTest.java
@@ -21,6 +21,7 @@ import com.yahoo.vespa.athenz.api.AthenzIdentity;
 import com.yahoo.vespa.athenz.api.AthenzUser;
 import com.yahoo.vespa.athenz.api.OktaAccessToken;
 import com.yahoo.vespa.config.SlimeUtils;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Instance;
 import com.yahoo.vespa.hosted.controller.LockedTenant;
 import com.yahoo.vespa.hosted.controller.api.application.v4.EnvironmentResource;
@@ -1238,12 +1239,12 @@ public class ApplicationApiTest extends ControllerContainerTest {
         createAthenzDomainWithAdmin(ATHENZ_TENANT_DOMAIN, USER_ID);
         configureAthenzIdentity(new com.yahoo.vespa.athenz.api.AthenzService(new AthenzDomain("another.domain"), "service"), true);
 
-        Instance instance = controllerTester.createApplication(ATHENZ_TENANT_DOMAIN.getName(), "tenant1", "application1", "default");
+        Application application = controllerTester.createApplication(ATHENZ_TENANT_DOMAIN.getName(), "tenant1", "application1", "default");
         ScrewdriverId screwdriverId = new ScrewdriverId(Long.toString(screwdriverProjectId));
-        controllerTester.authorize(ATHENZ_TENANT_DOMAIN, screwdriverId, ApplicationAction.deploy, instance);
+        controllerTester.authorize(ATHENZ_TENANT_DOMAIN, screwdriverId, ApplicationAction.deploy, application.id());
 
         controllerTester.jobCompletion(JobType.component)
-                        .application(instance.id())
+                        .application(application.id())
                         .projectId(screwdriverProjectId)
                         .uploadArtifact(applicationPackage)
                         .submit();
@@ -1270,12 +1271,12 @@ public class ApplicationApiTest extends ControllerContainerTest {
         createAthenzDomainWithAdmin(ATHENZ_TENANT_DOMAIN, USER_ID);
         configureAthenzIdentity(new com.yahoo.vespa.athenz.api.AthenzService(ATHENZ_TENANT_DOMAIN, "service"), true);
 
-        Instance instance = controllerTester.createApplication(ATHENZ_TENANT_DOMAIN.getName(), "tenant1", "application1", "default");
-        controllerTester.authorize(ATHENZ_TENANT_DOMAIN, screwdriverId, ApplicationAction.deploy, instance);
+        Application application = controllerTester.createApplication(ATHENZ_TENANT_DOMAIN.getName(), "tenant1", "application1", "default");
+        controllerTester.authorize(ATHENZ_TENANT_DOMAIN, screwdriverId, ApplicationAction.deploy, application.id());
 
         // Allow systemtest to succeed by notifying completion of system test
         controllerTester.jobCompletion(JobType.component)
-                        .application(instance.id())
+                        .application(application.id())
                         .projectId(screwdriverProjectId)
                         .uploadArtifact(applicationPackage)
                         .submit();
@@ -1367,12 +1368,12 @@ public class ApplicationApiTest extends ControllerContainerTest {
         createAthenzDomainWithAdmin(ATHENZ_TENANT_DOMAIN, USER_ID);
         configureAthenzIdentity(new com.yahoo.vespa.athenz.api.AthenzService(ATHENZ_TENANT_DOMAIN, "service"), false);
 
-        Instance instance = controllerTester.createApplication(ATHENZ_TENANT_DOMAIN.getName(), "tenant1", "application1", "default");
-        controllerTester.authorize(ATHENZ_TENANT_DOMAIN, screwdriverId, ApplicationAction.deploy, instance);
+        Application application = controllerTester.createApplication(ATHENZ_TENANT_DOMAIN.getName(), "tenant1", "application1", "default");
+        controllerTester.authorize(ATHENZ_TENANT_DOMAIN, screwdriverId, ApplicationAction.deploy, application.id());
 
         // Allow systemtest to succeed by notifying completion of system test
         controllerTester.jobCompletion(JobType.component)
-                        .application(instance.id())
+                        .application(application.id())
                         .projectId(screwdriverProjectId)
                         .uploadArtifact(applicationPackage)
                         .submit();
@@ -1404,12 +1405,12 @@ public class ApplicationApiTest extends ControllerContainerTest {
         createAthenzDomainWithAdmin(ATHENZ_TENANT_DOMAIN, USER_ID);
         configureAthenzIdentity(new com.yahoo.vespa.athenz.api.AthenzService(ATHENZ_TENANT_DOMAIN, "service"), true);
 
-        Instance instance = controllerTester.createApplication(ATHENZ_TENANT_DOMAIN.getName(), "tenant1", "application1", "default");
-        controllerTester.authorize(ATHENZ_TENANT_DOMAIN, screwdriverId, ApplicationAction.deploy, instance);
+        Application application = controllerTester.createApplication(ATHENZ_TENANT_DOMAIN.getName(), "tenant1", "application1", "default");
+        controllerTester.authorize(ATHENZ_TENANT_DOMAIN, screwdriverId, ApplicationAction.deploy, application.id());
 
         // Allow systemtest to succeed by notifying completion of system test
         controllerTester.jobCompletion(JobType.component)
-                .application(instance.id())
+                .application(application.id())
                 .projectId(screwdriverProjectId)
                 .uploadArtifact(applicationPackage)
                 .submit();
@@ -1430,7 +1431,7 @@ public class ApplicationApiTest extends ControllerContainerTest {
         addUserToHostedOperatorRole(HostedAthenzIdentities.from(HOSTED_VESPA_OPERATOR));
         tester.computeVersionStatus();
         long projectId = 1;
-        Instance app = controllerTester.createApplication();
+        Application app = controllerTester.createApplication();
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-central-1")
@@ -1442,7 +1443,7 @@ public class ApplicationApiTest extends ControllerContainerTest {
                 .application(app)
                 .projectId(projectId);
         job.type(JobType.component).uploadArtifact(applicationPackage).submit();
-        controllerTester.deploy(app, applicationPackage, TEST_ZONE);
+        controllerTester.deploy(app.id(), applicationPackage, TEST_ZONE);
         job.type(JobType.systemTest).submit();
 
         // Notifying about job started not by the controller fails
@@ -1482,7 +1483,7 @@ public class ApplicationApiTest extends ControllerContainerTest {
         controllerTester.containerTester().computeVersionStatus();
 
         long projectId = 1;
-        Instance app = controllerTester.createApplication();
+        Application app = controllerTester.createApplication();
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-central-1")
@@ -1494,9 +1495,9 @@ public class ApplicationApiTest extends ControllerContainerTest {
                 .projectId(projectId);
         job.type(JobType.component).uploadArtifact(applicationPackage).submit();
 
-        controllerTester.deploy(app, applicationPackage, TEST_ZONE);
+        controllerTester.deploy(app.id(), applicationPackage, TEST_ZONE);
         job.type(JobType.systemTest).submit();
-        controllerTester.deploy(app, applicationPackage, STAGING_ZONE);
+        controllerTester.deploy(app.id(), applicationPackage, STAGING_ZONE);
         job.type(JobType.stagingTest).error(DeploymentJobs.JobError.outOfCapacity).submit();
 
         // Appropriate error is recorded
@@ -1511,7 +1512,7 @@ public class ApplicationApiTest extends ControllerContainerTest {
 
     @Test
     public void applicationWithRoutingPolicy() {
-        Instance app = controllerTester.createApplication();
+        Application app = controllerTester.createApplication();
         ApplicationPackage applicationPackage = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .region("us-west-1")
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/application/JobControllerApiHandlerHelperTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/application/JobControllerApiHandlerHelperTest.java
index 043ce712636..2f009d16254 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/application/JobControllerApiHandlerHelperTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/application/JobControllerApiHandlerHelperTest.java
@@ -55,7 +55,7 @@ public class JobControllerApiHandlerHelperTest {
 
         // Revision 1 gets deployed everywhere.
         ApplicationVersion revision1 = tester.deployNewSubmission();
-        assertEquals(2, tester.app().deploymentJobs().projectId().getAsLong());
+        assertEquals(2, tester.instance().deploymentJobs().projectId().getAsLong());
 
         tester.clock().advance(Duration.ofMillis(1000));
         // Revision 2 gets deployed everywhere except in us-east-3.
@@ -80,9 +80,9 @@ public class JobControllerApiHandlerHelperTest {
         tester.cloud().set(FAILURE);
         tester.runner().run();
         assertEquals(testFailure, tester.jobs().last(appId, productionUsWest1).get().status());
-        assertEquals(revision2, tester.app().deployments().get(productionUsCentral1.zone(tester.tester().controller().system())).applicationVersion());
-        assertEquals(revision1, tester.app().deployments().get(productionUsEast3.zone(tester.tester().controller().system())).applicationVersion());
-        assertEquals(revision2, tester.app().deployments().get(productionUsWest1.zone(tester.tester().controller().system())).applicationVersion());
+        assertEquals(revision2, tester.instance().deployments().get(productionUsCentral1.zone(tester.tester().controller().system())).applicationVersion());
+        assertEquals(revision1, tester.instance().deployments().get(productionUsEast3.zone(tester.tester().controller().system())).applicationVersion());
+        assertEquals(revision2, tester.instance().deployments().get(productionUsWest1.zone(tester.tester().controller().system())).applicationVersion());
 
         tester.clock().advance(Duration.ofMillis(1000));
 
@@ -149,7 +149,7 @@ public class JobControllerApiHandlerHelperTest {
         var region = "us-west-1";
         var applicationPackage = new ApplicationPackageBuilder().region(region).build();
         // Deploy directly to production zone, like integration tests.
-        tester.tester().controller().applications().deploy(tester.app().id(), ZoneId.from("prod", region),
+        tester.tester().controller().applications().deploy(tester.instance().id(), ZoneId.from("prod", region),
                                                            Optional.of(applicationPackage),
                                                            new DeployOptions(true, Optional.empty(),
                                                                              false, false));
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/deployment/BadgeApiTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/deployment/BadgeApiTest.java
index 09555dd9f2e..35ec5b0e37e 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/deployment/BadgeApiTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/deployment/BadgeApiTest.java
@@ -2,7 +2,7 @@ package com.yahoo.vespa.hosted.controller.restapi.deployment;
 
 import com.yahoo.config.provision.AthenzService;
 import com.yahoo.config.provision.Environment;
-import com.yahoo.vespa.hosted.controller.Instance;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.api.integration.deployment.SourceRevision;
 import com.yahoo.vespa.hosted.controller.application.ApplicationPackage;
 import com.yahoo.vespa.hosted.controller.deployment.ApplicationPackageBuilder;
@@ -20,13 +20,13 @@ public class BadgeApiTest extends ControllerContainerTest {
     @Test
     public void testBadgeApi() {
         ContainerControllerTester tester = new ContainerControllerTester(container, responseFiles);
-        Instance instance = tester.createApplication("domain", "tenant", "application", "default");
+        Application application = tester.createApplication("domain", "tenant", "application", "default");
         ApplicationPackage packageWithService = new ApplicationPackageBuilder()
                 .environment(Environment.prod)
                 .athenzIdentity(com.yahoo.config.provision.AthenzDomain.from("domain"), AthenzService.from("service"))
                 .region("us-west-1")
                 .build();
-        tester.controller().jobController().submit(instance.id(),
+        tester.controller().jobController().submit(application.id(),
                                                    new SourceRevision("repository", "branch", "commit"),
                                                    "foo@bar",
                                                    123,
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/deployment/DeploymentApiTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/deployment/DeploymentApiTest.java
index adf48ea37cb..128ea0e6f7e 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/deployment/DeploymentApiTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/restapi/deployment/DeploymentApiTest.java
@@ -6,6 +6,7 @@ import com.yahoo.component.Version;
 import com.yahoo.config.provision.Environment;
 import com.yahoo.config.provision.HostName;
 import com.yahoo.config.provision.zone.ZoneId;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Instance;
 import com.yahoo.vespa.hosted.controller.Controller;
 import com.yahoo.vespa.hosted.controller.application.ApplicationPackage;
@@ -39,9 +40,9 @@ public class DeploymentApiTest extends ControllerContainerTest {
                 .build();
 
         // 3 applications deploy on current system version
-        Instance failingInstance = tester.createApplication("domain1", "tenant1", "application1", "default");
-        Instance productionInstance = tester.createApplication("domain2", "tenant2", "application2", "default");
-        Instance instanceWithoutDeployment = tester.createApplication("domain3", "tenant3", "application3", "default");
+        Application failingInstance = tester.createApplication("domain1", "tenant1", "application1", "default");
+        Application productionInstance = tester.createApplication("domain2", "tenant2", "application2", "default");
+        Application instanceWithoutDeployment = tester.createApplication("domain3", "tenant3", "application3", "default");
         tester.deployCompletely(failingInstance, applicationPackage, 1L, false);
         tester.deployCompletely(productionInstance, applicationPackage, 2L, false);
 
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/rotation/RotationRepositoryTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/rotation/RotationRepositoryTest.java
index 78f36fdf4a3..c563a4950de 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/rotation/RotationRepositoryTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/rotation/RotationRepositoryTest.java
@@ -2,6 +2,7 @@
 package com.yahoo.vespa.hosted.controller.rotation;
 
 import com.yahoo.config.provision.SystemName;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Instance;
 import com.yahoo.vespa.hosted.controller.ControllerTester;
 import com.yahoo.vespa.hosted.controller.application.ApplicationPackage;
@@ -50,19 +51,21 @@ public class RotationRepositoryTest {
 
     private DeploymentTester tester;
     private RotationRepository repository;
+    private Application application;
     private Instance instance;
     
     @Before
     public void before() {
         tester = new DeploymentTester(new ControllerTester(rotationsConfig));
         repository = tester.controller().applications().rotationRepository();
-        instance = tester.createApplication("app1", "tenant1", 11L, 1L);
+        application = tester.createApplication("app1", "tenant1", 11L, 1L);
+        instance = tester.instance(application.id());
     }
 
     @Test
     public void assigns_and_reuses_rotation() {
         // Deploying assigns a rotation
-        tester.deployCompletely(instance, applicationPackage);
+        tester.deployCompletely(application, applicationPackage);
         Rotation expected = new Rotation(new RotationId("foo-1"), "foo-1.com");
 
         instance = tester.applications().require(instance.id());
@@ -81,7 +84,7 @@ public class RotationRepositoryTest {
                 .region("us-west-1")
                 .searchDefinition("search foo { }") // Update application package so there is something to deploy
                 .build();
-        tester.deployCompletely(instance, applicationPackage, 43);
+        tester.deployCompletely(application, applicationPackage, 43);
         assertEquals(List.of(expected.id()), rotationIds(tester.applications().require(instance.id()).rotations()));
     }
     
@@ -89,13 +92,13 @@ public class RotationRepositoryTest {
     public void strips_whitespace_in_rotation_fqdn() {
         DeploymentTester tester = new DeploymentTester(new ControllerTester(rotationsConfigWhitespaces));
         RotationRepository repository = tester.controller().applications().rotationRepository();
-        Instance instance = tester.createApplication("app2", "tenant2", 22L,
-                                                     2L);
-        tester.deployCompletely(instance, applicationPackage);
-        instance = tester.applications().require(instance.id());
+        Application application2 = tester.createApplication("app2", "tenant2", 22L, 2L);
+
+        tester.deployCompletely(application2, applicationPackage);
+        Instance instance2 = tester.applications().require(application2.id());
 
         try (RotationLock lock = repository.lock()) {
-            Rotation rotation = repository.getOrAssignRotation(instance, lock);
+            Rotation rotation = repository.getOrAssignRotation(instance2, lock);
             Rotation assignedRotation = new Rotation(new RotationId("foo-1"), "foo-1.com");
             assertEquals(assignedRotation, rotation);
         }
@@ -104,19 +107,17 @@ public class RotationRepositoryTest {
     @Test
     public void out_of_rotations() {
         // Assigns 1 rotation
-        tester.deployCompletely(instance, applicationPackage);
+        tester.deployCompletely(application, applicationPackage);
 
         // Assigns 1 more
-        Instance instance2 = tester.createApplication("app2", "tenant2", 22L,
-                                                      2L);
-        tester.deployCompletely(instance2, applicationPackage);
+        Application application2 = tester.createApplication("app2", "tenant2", 22L, 2L);
+        tester.deployCompletely(application2, applicationPackage);
 
         // We're now out of rotations
         thrown.expect(IllegalStateException.class);
         thrown.expectMessage("no rotations available");
-        Instance instance3 = tester.createApplication("app3", "tenant3", 33L,
-                                                      3L);
-        tester.deployCompletely(instance3, applicationPackage);
+        Application application3 = tester.createApplication("app3", "tenant3", 33L, 3L);
+        tester.deployCompletely(application3, applicationPackage);
     }
 
     @Test
@@ -125,11 +126,10 @@ public class RotationRepositoryTest {
                 .globalServiceId("foo")
                 .region("us-east-3")
                 .build();
-        Instance instance = tester.createApplication("app2", "tenant2", 22L,
-                                                     2L);
+        Application application2 = tester.createApplication("app2", "tenant2", 22L, 2L);
         thrown.expect(RuntimeException.class);
         thrown.expectMessage("less than 2 prod zones are defined");
-        tester.deployCompletely(instance, applicationPackage);
+        tester.deployCompletely(application2, applicationPackage);
     }
 
     @Test
@@ -138,9 +138,8 @@ public class RotationRepositoryTest {
                 .region("us-east-3")
                 .region("us-west-1")
                 .build();
-        tester.deployCompletely(instance, applicationPackage);
-        Instance app = tester.applications().require(instance.id());
-        assertTrue(app.rotations().isEmpty());
+        tester.deployCompletely(application, applicationPackage);
+        assertTrue(tester.instance(application.id()).rotations().isEmpty());
     }
 
     @Test
@@ -150,11 +149,10 @@ public class RotationRepositoryTest {
                 .region("us-east-3")
                 .region("us-west-1")
                 .build();
-        Instance instance = tester.createApplication("app2", "tenant2", 22L,
-                                                     2L);
-        tester.deployCompletely(instance, applicationPackage);
-        assertEquals(List.of(new RotationId("foo-1")), rotationIds(tester.applications().require(instance.id()).rotations()));
-        assertEquals("https://cd--app2--tenant2.global.vespa.oath.cloud:4443/", tester.applications().require(instance.id())
+        Application application2 = tester.createApplication("app2", "tenant2", 22L, 2L);
+        tester.deployCompletely(application2, applicationPackage);
+        assertEquals(List.of(new RotationId("foo-1")), rotationIds(tester.instance(application2.id()).rotations()));
+        assertEquals("https://cd--app2--tenant2.global.vespa.oath.cloud:4443/", tester.instance(application2.id())
                 .endpointsIn(SystemName.cd).main().get().url().toString());
     }
 
diff --git a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/versions/VersionStatusTest.java b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/versions/VersionStatusTest.java
index 3d12fe382ce..3aae5b9b2ae 100644
--- a/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/versions/VersionStatusTest.java
+++ b/controller-server/src/test/java/com/yahoo/vespa/hosted/controller/versions/VersionStatusTest.java
@@ -7,6 +7,7 @@ import com.yahoo.component.Vtag;
 import com.yahoo.config.provision.Environment;
 import com.yahoo.config.provision.HostName;
 import com.yahoo.config.provision.zone.ZoneApi;
+import com.yahoo.vespa.hosted.controller.Application;
 import com.yahoo.vespa.hosted.controller.Instance;
 import com.yahoo.vespa.hosted.controller.Controller;
 import com.yahoo.vespa.hosted.controller.ControllerTester;
@@ -135,9 +136,9 @@ public class VersionStatusTest {
         tester.upgradeSystem(version1);
 
         // Setup applications
-        Instance app1 = tester.createAndDeploy("app1", 11, applicationPackage);
-        Instance app2 = tester.createAndDeploy("app2", 22, applicationPackage);
-        Instance app3 = tester.createAndDeploy("app3", 33, applicationPackage);
+        Application app1 = tester.createAndDeploy("app1", 11, applicationPackage);
+        Application app2 = tester.createAndDeploy("app2", 22, applicationPackage);
+        Application app3 = tester.createAndDeploy("app3", 33, applicationPackage);
 
         // version2 is released
         tester.upgradeSystem(version2);
@@ -175,25 +176,25 @@ public class VersionStatusTest {
         tester.upgradeSystem(version0);
 
         // Setup applications - all running on version0
-        Instance canary0 = tester.createAndDeploy("canary0", 1, "canary");
-        Instance canary1 = tester.createAndDeploy("canary1", 2, "canary");
-        Instance canary2 = tester.createAndDeploy("canary2", 3, "canary");
-        Instance default0 = tester.createAndDeploy("default0", 4, "default");
-        Instance default1 = tester.createAndDeploy("default1", 5, "default");
-        Instance default2 = tester.createAndDeploy("default2", 6, "default");
-        Instance default3 = tester.createAndDeploy("default3", 7, "default");
-        Instance default4 = tester.createAndDeploy("default4", 8, "default");
-        Instance default5 = tester.createAndDeploy("default5", 9, "default");
-        Instance default6 = tester.createAndDeploy("default6", 10, "default");
-        Instance default7 = tester.createAndDeploy("default7", 11, "default");
-        Instance default8 = tester.createAndDeploy("default8", 12, "default");
-        Instance default9 = tester.createAndDeploy("default9", 13, "default");
-        Instance conservative0 = tester.createAndDeploy("conservative1", 14, "conservative");
+        Application canary0 = tester.createAndDeploy("canary0", 1, "canary");
+        Application canary1 = tester.createAndDeploy("canary1", 2, "canary");
+        Application canary2 = tester.createAndDeploy("canary2", 3, "canary");
+        Application default0 = tester.createAndDeploy("default0", 4, "default");
+        Application default1 = tester.createAndDeploy("default1", 5, "default");
+        Application default2 = tester.createAndDeploy("default2", 6, "default");
+        Application default3 = tester.createAndDeploy("default3", 7, "default");
+        Application default4 = tester.createAndDeploy("default4", 8, "default");
+        Application default5 = tester.createAndDeploy("default5", 9, "default");
+        Application default6 = tester.createAndDeploy("default6", 10, "default");
+        Application default7 = tester.createAndDeploy("default7", 11, "default");
+        Application default8 = tester.createAndDeploy("default8", 12, "default");
+        Application default9 = tester.createAndDeploy("default9", 13, "default");
+        Application conservative0 = tester.createAndDeploy("conservative1", 14, "conservative");
 
         // Applications that do not affect confidence calculation:
 
         // Application without deployment
-        Instance ignored0 = tester.createApplication("ignored0", "tenant1", 1000, 1000L);
+        Application ignored0 = tester.createApplication("ignored0", "tenant1", 1000, 1000L);
 
         assertEquals("All applications running on this version: High",
                      Confidence.high, confidence(tester.controller(), version0));
@@ -310,7 +311,7 @@ public class VersionStatusTest {
         tester.upgradeSystem(version0);
 
         // Create and deploy application on current version
-        Instance app = tester.createAndDeploy("app", 1, "canary");
+        Application app = tester.createAndDeploy("app", 1, "canary");
         tester.computeVersionStatus();
         assertEquals(Confidence.high, confidence(tester.controller(), version0));
 
@@ -368,9 +369,9 @@ public class VersionStatusTest {
         assertEquals(5, tester.hourOfDayAfter(Duration.ZERO));
         Version version0 = Version.fromString("7.1");
         tester.upgradeSystem(version0);
-        Instance canary0 = tester.createAndDeploy("canary0", 1, "canary");
-        Instance canary1 = tester.createAndDeploy("canary1", 1, "canary");
-        Instance default0 = tester.createAndDeploy("default0", 1, "default");
+        Application canary0 = tester.createAndDeploy("canary0", 1, "canary");
+        Application canary1 = tester.createAndDeploy("canary1", 1, "canary");
+        Application default0 = tester.createAndDeploy("default0", 1, "default");
         tester.computeVersionStatus();
         assertSame(Confidence.high, tester.controller().versionStatus().version(version0).confidence());