diff --git a/src/Container/ApplicationFactory.php b/src/Container/ApplicationFactory.php
index b1a539e8..419400d9 100644
--- a/src/Container/ApplicationFactory.php
+++ b/src/Container/ApplicationFactory.php
@@ -422,7 +422,7 @@ private function createCollectionMapper(Application $app)
             self::ROUTE_RESULT_OBSERVER_MIDDLEWARE
         ];
 
-        return function ($item) use ($app, $pipelineMap, $appMiddlewares) {
+        return function ($item) use ($pipelineMap, $appMiddlewares) {
             if (in_array($item, $appMiddlewares, true)) {
                 return ['middleware' => $pipelineMap($item)];
             }