diff --git a/extend.php b/extend.php
index e8b9b0c..6bf4c5e 100644
--- a/extend.php
+++ b/extend.php
@@ -18,6 +18,7 @@
 use Flarum\Extend;
 use Flarum\User\Event\Registered;
 use Flarum\User\Event\Saving as UserSaving;
+use Flarum\User\User;
 use FoF\Doorman\Api\Controllers;
 use FoF\Doorman\Api\Serializers\DoorkeySerializer;
 use FoF\Doorman\Validators\DoorkeyLoginValidator;
@@ -31,6 +32,9 @@
         ->js(__DIR__.'/js/dist/admin.js')
         ->css(__DIR__.'/resources/less/admin.less'),
 
+    (new Extend\Model(User::class))
+        ->cast('invite_code', 'string'),
+
     (new Extend\Routes('api'))
         ->post('/fof/doorkeys', 'fof.doorkey.create', Controllers\CreateDoorkeyController::class)
         ->post('/fof/doorkeys/invites', 'fof.doorkey.invite', Controllers\SendInvitesController::class)
diff --git a/src/Api/Controllers/ListDoorkeysController.php b/src/Api/Controllers/ListDoorkeysController.php
index 974ca55..cf97742 100644
--- a/src/Api/Controllers/ListDoorkeysController.php
+++ b/src/Api/Controllers/ListDoorkeysController.php
@@ -22,9 +22,6 @@
 
 class ListDoorkeysController extends AbstractListController
 {
-    /**
-     * @var DoorkeySerializer
-     */
     public $serializer = DoorkeySerializer::class;
 
     /**
diff --git a/src/Commands/EditDoorkeyHandler.php b/src/Commands/EditDoorkeyHandler.php
index eea3a2f..b07d36c 100644
--- a/src/Commands/EditDoorkeyHandler.php
+++ b/src/Commands/EditDoorkeyHandler.php
@@ -36,11 +36,11 @@ public function __construct(DoorkeyValidator $validator)
     }
 
     /**
-     * @param EditRank $command
+     * @param EditDoorkey $command
      *
      * @throws PermissionDeniedException
      *
-     * @return Rank
+     * @return Doorkey
      */
     public function handle(EditDoorkey $command)
     {
diff --git a/src/Doorkey.php b/src/Doorkey.php
index b90c971..32bb857 100644
--- a/src/Doorkey.php
+++ b/src/Doorkey.php
@@ -16,6 +16,13 @@
 use Flarum\Database\AbstractModel;
 use Flarum\Group\Group;
 
+/**
+ * @property string $key
+ * @property int $group_id
+ * @property int $max_uses
+ * @property int $activates
+ * @property int $uses
+ */
 class Doorkey extends AbstractModel
 {
     /**
diff --git a/src/Listeners/PostRegisterOperations.php b/src/Listeners/PostRegisterOperations.php
index ec2b5ba..4ee6f0f 100644
--- a/src/Listeners/PostRegisterOperations.php
+++ b/src/Listeners/PostRegisterOperations.php
@@ -21,8 +21,16 @@
 
 class PostRegisterOperations
 {
+    /**
+     * @var SettingsRepositoryInterface
+     */
     protected $settings;
 
+    /**
+     * @var Dispatcher
+     */
+    protected $events;
+
     public function __construct(SettingsRepositoryInterface $settings, Dispatcher $events)
     {
         $this->settings = $settings;