diff --git a/platform/framework/src/register/ServiceCompositor.js b/platform/framework/src/register/ServiceCompositor.js
index 2f8e5d5f29..a3b9a49949 100644
--- a/platform/framework/src/register/ServiceCompositor.js
+++ b/platform/framework/src/register/ServiceCompositor.js
@@ -28,7 +28,7 @@ define(
                     " ",
                     extension.key,
                     " from bundle ",
-                    extension.bundle.path,
+                    (extension.bundle || { path: "unknown bundle" }).path,
                     "; skipping."
                 ].join(""));
             }
@@ -165,6 +165,11 @@ define(
                 });
             }
 
+            // Register composite services in phases:
+            // * Register providers
+            // * Register aggregators (which use providers)
+            // * Register decorators (which use anything)
+            // Then, register the latest candidate as a plain service.
             function registerComposites(providers, aggregators, decorators) {
                 providers.forEach(registerProvider);
                 registerProviderSets();
@@ -173,6 +178,7 @@ define(
                 registerLatest();
             }
 
+            // Initial point of entry; just separate components by type
             function registerCompositeServices(components) {
                 registerComposites(
                     components.filter(hasType("provider")),
diff --git a/platform/framework/test/register/ServiceCompositorSpec.js b/platform/framework/test/register/ServiceCompositorSpec.js
index f3de35ee50..ace44ec144 100644
--- a/platform/framework/test/register/ServiceCompositorSpec.js
+++ b/platform/framework/test/register/ServiceCompositorSpec.js
@@ -1,14 +1,197 @@
-/*global define,Promise,describe,it,expect,beforeEach*/
+/*global define,Promise,describe,it,expect,beforeEach,jasmine*/
 
 /**
  * ServiceCompositorSpec. Created by vwoeltje on 11/6/14.
  */
 define(
-    [],
-    function () {
+    ["../../src/register/ServiceCompositor"],
+    function (ServiceCompositor) {
         "use strict";
 
-        describe("", function () {
+        describe("The service compositor", function () {
+            var registered,
+                mockApp,
+                mockLog,
+                compositor;
+
+
+            beforeEach(function () {
+                registered = {};
+
+                mockApp = jasmine.createSpyObj("app", [ "service" ]);
+                mockLog = jasmine.createSpyObj("$log", [ "error", "warn", "info", "debug" ]);
+
+                mockApp.service.andCallFake(function (name, value) {
+                    var factory = value[value.length - 1];
+
+                    registered[name] = {
+                        depends: value.slice(0, value.length - 1),
+                        callback: value[value.length - 1]
+                    };
+
+                    // Track what name it was registered under
+                    factory.registeredName = name;
+                });
+
+                compositor = new ServiceCompositor(mockApp, mockLog);
+            });
+
+            it("allows composite services to be registered", function () {
+                compositor.registerCompositeServices([
+                    { type: "provider", provides: "testService" }
+                ]);
+
+                expect(mockApp.service).toHaveBeenCalled();
+            });
+
+            it("allows composite services to be registered", function () {
+                // Prepare components that look like resolved extensions
+                var components, name;
+                function MyDecorator() { return {}; }
+                function MyOtherDecorator() { return {}; }
+                function MyProvider() { return {}; }
+                function MyOtherProvider() { return {}; }
+                function MyAggregator() { return {}; }
+
+                components = [
+                    MyDecorator,
+                    MyProvider,
+                    MyAggregator,
+                    MyOtherDecorator,
+                    MyOtherProvider
+                ];
+
+                MyDecorator.type = "decorator";
+                MyOtherDecorator.type = "decorator";
+                MyProvider.type = "provider";
+                MyOtherProvider.type = "provider";
+                MyAggregator.type = "aggregator";
+                components.forEach(function (c) { c.provides = "testService"; });
+
+                // Add some test dependencies, to check prepending
+                MyOtherDecorator.depends = [ "someOtherService" ];
+                MyAggregator.depends = [ "tests[]" ];
+
+                // Register!
+                compositor.registerCompositeServices(components);
+
+                expect(mockApp.service).toHaveBeenCalled();
+
+                // Verify some interesting spots on dependency graph
+                expect(registered.testService.depends).toEqual([
+                    MyOtherDecorator.registeredName
+                ]);
+                expect(registered[MyOtherDecorator.registeredName].depends).toEqual([
+                    "someOtherService",
+                    MyDecorator.registeredName
+                ]);
+                expect(registered[MyAggregator.registeredName].depends.length).toEqual(2);
+                // Get the name of the group of providers
+                name = registered[MyAggregator.registeredName].depends[1];
+                // ...it should depend on both providers
+                expect(registered[name].depends).toEqual([
+                    MyProvider.registeredName,
+                    MyOtherProvider.registeredName
+                ]);
+            });
+
+            it("allows registered composite services to be instantiated", function () {
+                // Prepare components that look like resolved extensions
+                var components, name;
+                function MyProvider() { return {}; }
+                function MyOtherProvider() { return {}; }
+                function MyAggregator() { return {}; }
+
+                components = [ MyProvider, MyAggregator, MyOtherProvider ];
+
+                MyProvider.type = "provider";
+                MyOtherProvider.type = "provider";
+                MyAggregator.type = "aggregator";
+                components.forEach(function (c) { c.provides = "testService"; });
+
+                // Register!
+                compositor.registerCompositeServices(components);
+
+                expect(mockApp.service).toHaveBeenCalled();
+
+                // Test service should just be a reflecting dependency;
+                // it will depend upon (then return) the aggregator.
+                expect(registered.testService.callback("hello")).toEqual("hello");
+
+                // The aggregated provider dependencies should be similar,
+                // except they should reflect back the array of arguments.
+                // Get the name of the group of providers
+                name = registered[MyAggregator.registeredName].depends[0];
+                // ...it should depend on both providers
+                expect(registered[name].callback(1, 2, "hello")).toEqual([1, 2, "hello"]);
+
+            });
+
+            it("warns and skips components with no service type", function () {
+                // Prepare components that look like resolved extensions
+                var components;
+                function MyProvider() { return {}; }
+                function MyDecorator() { return {}; }
+                function MyAggregator() { return {}; }
+
+                components = [ MyProvider, MyAggregator, MyDecorator ];
+
+                MyProvider.type = "provider";
+                MyDecorator.type = "decorator";
+                MyAggregator.type = "aggregator";
+
+                // Notably, we don't do
+                // components.forEach(function (c) { c.provides = "testService"; });
+
+                // Try to register...
+                compositor.registerCompositeServices(components);
+
+                // Nothing should have gotten registered
+                expect(mockApp.service).not.toHaveBeenCalled();
+
+                // Should have gotten one warning for each skipped component
+                expect(mockLog.warn.calls.length).toEqual(3);
+            });
+
+            it("warns about and skips aggregators with zero providers", function () {
+                // Prepare components that look like resolved extensions
+                var components;
+                function MyAggregator() { return {}; }
+
+                components = [ MyAggregator ];
+
+                MyAggregator.type = "aggregator";
+                MyAggregator.provides = "testService";
+
+                // Try to register...
+                compositor.registerCompositeServices(components);
+
+                // Nothing should have gotten registered
+                expect(mockApp.service).not.toHaveBeenCalled();
+
+                // Should have gotten a warning
+                expect(mockLog.warn).toHaveBeenCalled();
+            });
+
+            it("warns about and skips decorators with nothing to decorate", function () {
+                // Prepare components that look like resolved extensions
+                var components;
+                function MyDecorator() { return {}; }
+
+                components = [ MyDecorator ];
+
+                MyDecorator.type = "decorator";
+                MyDecorator.provides = "testService";
+
+                // Try to register...
+                compositor.registerCompositeServices(components);
+
+                // Nothing should have gotten registered
+                expect(mockApp.service).not.toHaveBeenCalled();
+
+                // Should have gotten a warning
+                expect(mockLog.warn).toHaveBeenCalled();
+            });
 
         });
     }