diff --git a/app/index.html b/app/index.html
index eca1596..83ff689 100644
--- a/app/index.html
+++ b/app/index.html
@@ -9,7 +9,7 @@
 <div class="container-fluid" ng-controller="IndexController as index">
     <h3>Messages stored on Google Data Store:</h3>
 
-    <ul ng-cloak>
+    <ul id="messages" ng-cloak>
         <li ng-repeat="message in index.messages track by $index">
             {{message}}
         </li>
@@ -19,7 +19,7 @@ <h3>Messages stored on Google Data Store:</h3>
         <div class="form-group">
             <input type="text" ng-model="message" class="form-control" id="message" placeholder="Enter a new message">
         </div>
-        <button type="submit" class="btn btn-default" ng-click="index.create(message)">Add</button>
+        <button id="add" type="submit" class="btn btn-default" ng-click="index.create(message)">Add</button>
     </form>
 </div>
 
diff --git a/src/main/java/gageot/net/Messages.java b/src/main/java/gageot/net/Messages.java
new file mode 100644
index 0000000..a57a46a
--- /dev/null
+++ b/src/main/java/gageot/net/Messages.java
@@ -0,0 +1,46 @@
+/**
+ * Copyright (C) 2014 david@gageot.net
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *         http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License
+ */
+package gageot.net;
+
+import com.google.appengine.api.datastore.Entity;
+import com.google.appengine.api.datastore.Query;
+
+import java.util.Date;
+import java.util.List;
+
+import static com.google.appengine.api.datastore.DatastoreServiceFactory.getDatastoreService;
+import static com.google.appengine.api.datastore.FetchOptions.Builder.withLimit;
+import static com.google.appengine.api.datastore.KeyFactory.createKey;
+import static com.google.appengine.api.datastore.Query.SortDirection.DESCENDING;
+import static net.codestory.Fluent.of;
+
+public class Messages {
+  public List<String> list() {
+    Query query = new Query("Message", createKey("Messages", "list")).addSort("date", DESCENDING);
+
+    List<Entity> messages = getDatastoreService().prepare(query).asList(withLimit(100));
+
+    return of(messages).map(message -> (String) message.getProperty("message")).toList();
+  }
+
+  public void create(String message) {
+    Entity entity = new Entity("Message", createKey("Messages", "list"));
+    entity.setProperty("message", message);
+    entity.setProperty("date", new Date());
+
+    getDatastoreService().put(entity);
+  }
+}
diff --git a/src/main/java/gageot/net/MessagesResource.java b/src/main/java/gageot/net/MessagesResource.java
index 8f7ecfb..c61f760 100644
--- a/src/main/java/gageot/net/MessagesResource.java
+++ b/src/main/java/gageot/net/MessagesResource.java
@@ -15,36 +15,25 @@
  */
 package gageot.net;
 
-import com.google.appengine.api.datastore.Entity;
-import com.google.appengine.api.datastore.Query;
 import net.codestory.http.annotations.Get;
 import net.codestory.http.annotations.Post;
 
-import java.util.Date;
 import java.util.List;
 
-import static com.google.appengine.api.datastore.DatastoreServiceFactory.getDatastoreService;
-import static com.google.appengine.api.datastore.FetchOptions.Builder.withLimit;
-import static com.google.appengine.api.datastore.KeyFactory.createKey;
-import static com.google.appengine.api.datastore.Query.SortDirection.DESCENDING;
-import static net.codestory.Fluent.of;
-
 public class MessagesResource {
-  @Get("/message/list")
-  public List<String> list() {
-    Query query = new Query("Message", createKey("Messages", "list")).addSort("date", DESCENDING);
+  private final Messages messages;
 
-    List<Entity> messages = getDatastoreService().prepare(query).asList(withLimit(100));
+  public MessagesResource(Messages messages) {
+    this.messages = messages;
+  }
 
-    return of(messages).map(message -> (String) message.getProperty("message")).toList();
+  @Get("/message/list")
+  public List<String> list() {
+    return messages.list();
   }
 
   @Post("/message")
   public void create(String message) {
-    Entity entity = new Entity("Message", createKey("Messages", "list"));
-    entity.setProperty("message", message);
-    entity.setProperty("date", new Date());
-
-    getDatastoreService().put(entity);
+    messages.create(message);
   }
 }
diff --git a/src/test/java/gageot/net/MainWebTest.java b/src/test/java/gageot/net/MainWebTest.java
index 1a29a83..4d00034 100644
--- a/src/test/java/gageot/net/MainWebTest.java
+++ b/src/test/java/gageot/net/MainWebTest.java
@@ -16,11 +16,23 @@
 package gageot.net;
 
 import net.codestory.http.WebServer;
+import net.codestory.http.injection.Singletons;
+import net.codestory.http.routes.Routes;
 import net.codestory.simplelenium.SeleniumTest;
 import org.junit.Test;
 
+import java.util.ArrayList;
+import java.util.List;
+
 public class MainWebTest extends SeleniumTest {
-  WebServer webServer = new WebServer().configure(MainWeb.WebConfiguration.class).startOnRandomPort();
+  WebServer webServer = new WebServer().configure(new MainWeb.WebConfiguration() {
+    @Override
+    public void configure(Routes routes) {
+      super.configure(routes);
+
+      routes.setIocAdapter(new Singletons().register(Messages.class, messages)); // Install dependency mock
+    }
+  }).startOnRandomPort();
 
   @Override
   protected String getDefaultBaseUrl() {
@@ -28,9 +40,39 @@ protected String getDefaultBaseUrl() {
   }
 
   @Test
-  public void index() {
+  public void show_messages() {
+    messages.create("Message01");
+    messages.create("Message02");
+
     goTo("/");
 
     find("h2").should().contain("Managed VMs Sample Project");
+    find("#messages").should().contain("Message01", "Message02");
   }
+
+  @Test
+  public void add_message() {
+    messages.create("FirstMessage");
+
+    goTo("/");
+
+    find("#message").fill("SecondMessage");
+    find("#add").click();
+
+    find("#messages").should().contain("FirstMessage", "SecondMessage");
+  }
+
+  Messages messages = new Messages() {
+    private final List<String> messages = new ArrayList<>();
+
+    @Override
+    public List<String> list() {
+      return messages;
+    }
+
+    @Override
+    public void create(String message) {
+      messages.add(message);
+    }
+  };
 }
\ No newline at end of file