diff --git a/Admin/Install/Navigation.php b/Admin/Install/Navigation.php
index 5aa1639..e832603 100644
--- a/Admin/Install/Navigation.php
+++ b/Admin/Install/Navigation.php
@@ -36,7 +36,7 @@ class Navigation
      *
      * @since  1.0.0
      */
-    public static function install(string $path = null, DatabasePool $dbPool = null) : void
+    public static function install(string $path, DatabasePool $dbPool) : void
     {
         \Modules\Navigation\Admin\Installer::installExternal($dbPool, ['path' => __DIR__ . '/Navigation.install.json']);
     }
diff --git a/Controller/BackendController.php b/Controller/BackendController.php
index df330e3..cfc2374 100644
--- a/Controller/BackendController.php
+++ b/Controller/BackendController.php
@@ -40,7 +40,7 @@ final class BackendController extends Controller
      * @since  1.0.0
      * @codeCoverageIgnore
      */
-    public function viewProjectList(RequestAbstract $request, ResponseAbstract $response, $data = null) : \Serializable
+    public function viewProjectList(RequestAbstract $request, ResponseAbstract $response, $data = null) : RenderableInterface
     {
         $view = new View($this->app, $request, $response);
         $view->setTemplate('/Modules/ResearchDevelopment/Theme/Backend/rnd-list');
@@ -59,7 +59,7 @@ final class BackendController extends Controller
      * @since  1.0.0
      * @codeCoverageIgnore
      */
-    public function viewProjectCreate(RequestAbstract $request, ResponseAbstract $response, $data = null) : \Serializable
+    public function viewProjectCreate(RequestAbstract $request, ResponseAbstract $response, $data = null) : RenderableInterface
     {
         $view = new View($this->app, $request, $response);
         $view->setTemplate('/Modules/ResearchDevelopment/Theme/Backend/rnd-create');