diff --git a/src/ApiClient.php b/src/ApiClient.php
index 831219e..8393ec9 100644
--- a/src/ApiClient.php
+++ b/src/ApiClient.php
@@ -360,9 +360,13 @@ public function postMessage(Message $message)
         $options = [
             'text' => $message->getText(),
             'channel' => $message->data['channel'],
-            'as_user' => true,
+            'as_user' => $message->isAsUser(),
         ];
 
+        if ($message->getUsername()) {
+            $options['username'] = $message->getUsername();
+        }
+
         if ($message->hasAttachments()) {
             $options['attachments'] = json_encode($message->getAttachments());
         }
diff --git a/src/Message/Message.php b/src/Message/Message.php
index 035b3c3..0327cab 100644
--- a/src/Message/Message.php
+++ b/src/Message/Message.php
@@ -68,6 +68,27 @@ public function getUser()
         return $this->client->getUserById($this->data['user']);
     }
 
+    /**
+     * Send message as user or not.
+     * By default sends as user.
+     *
+     * @return bool
+     */
+    public function isAsUser()
+    {
+        return isset($this->data['as_user']) ? $this->data['as_user'] : true;
+    }
+
+    /**
+     * Get message's user display name
+     *
+     * @return string
+     */
+    public function getUsername()
+    {
+        return isset($this->data['username']) ? $this->data['username'] : '';
+    }
+
     /**
      * {@inheritDoc}
      */
diff --git a/src/RealTimeClient.php b/src/RealTimeClient.php
index be0480e..7e66097 100644
--- a/src/RealTimeClient.php
+++ b/src/RealTimeClient.php
@@ -388,13 +388,12 @@ private function onMessage(WebSocketMessageInterface $message)
                     break;
 
                 case 'channel_created':
-                    $this->getChannelById($payload['channel']['id'])->then(function (Channel $channel) {
-                        $this->channels[$channel->getId()] = $channel;
-                    });
+                    $channel = new Channel($this, $payload['channel']);
+                    $this->channels[$channel->getId()] = $channel;
                     break;
 
                 case 'channel_deleted':
-                    unset($this->channels[$payload['channel']['id']]);
+                    unset($this->channels[$payload['channel']]);
                     break;
 
                 case 'channel_rename':
@@ -403,11 +402,11 @@ private function onMessage(WebSocketMessageInterface $message)
                     break;
 
                 case 'channel_archive':
-                    $this->channels[$payload['channel']['id']]->data['is_archived'] = true;
+                    $this->channels[$payload['channel']]->data['is_archived'] = true;
                     break;
 
                 case 'channel_unarchive':
-                    $this->channels[$payload['channel']['id']]->data['is_archived'] = false;
+                    $this->channels[$payload['channel']]->data['is_archived'] = false;
                     break;
 
                 case 'group_joined':
@@ -416,16 +415,16 @@ private function onMessage(WebSocketMessageInterface $message)
                     break;
 
                 case 'group_rename':
-                    $this->groups[$payload['group']['id']]->data['name']
+                    $this->groups[$payload['channel']['id']]->data['name']
                         = $payload['channel']['name'];
                     break;
 
                 case 'group_archive':
-                    $this->groups[$payload['group']['id']]->data['is_archived'] = true;
+                    $this->groups[$payload['channel']]->data['is_archived'] = true;
                     break;
 
                 case 'group_unarchive':
-                    $this->groups[$payload['group']['id']]->data['is_archived'] = false;
+                    $this->groups[$payload['channel']]->data['is_archived'] = false;
                     break;
 
                 case 'im_created':