diff --git a/src/App.php b/src/App.php
index 983e52f..febf6f1 100644
--- a/src/App.php
+++ b/src/App.php
@@ -89,7 +89,7 @@ public function process(ServerRequestInterface $request, ResponseInterface $resp
             }
 
             foreach (array_reverse($route->getMiddlewares()) as $middleware) {
-                $controller->addMiddleware($this->container[$middleware]);
+                $controller->addMiddleware($this->container->get($middleware));
             }
 
             return $controller->callMiddlewareStack($request, $response);
diff --git a/src/ClosureController.php b/src/ClosureController.php
index 2241c7f..8260730 100644
--- a/src/ClosureController.php
+++ b/src/ClosureController.php
@@ -24,7 +24,7 @@ public function __construct(\Closure $controller)
     public function __invoke(
         ServerRequestInterface $request,
         ResponseInterface $response,
-        \Closure $next = null
+        callable $next = null
     ): ResponseInterface {
         return ($this->controller)($request,$response);
     }
diff --git a/src/Controller.php b/src/Controller.php
index d675f86..c7c5c28 100644
--- a/src/Controller.php
+++ b/src/Controller.php
@@ -24,7 +24,7 @@ public function __construct(ControllerInterface $controller)
     public function __invoke(
         ServerRequestInterface $request,
         ResponseInterface $response,
-        \Closure $next = null
+        callable $next = null
     ): ResponseInterface {
         return ($this->controller)($request,$response);
     }
diff --git a/src/Interfaces/MiddlewareInterface.php b/src/Interfaces/MiddlewareInterface.php
index 57caaa2..6dfef7c 100644
--- a/src/Interfaces/MiddlewareInterface.php
+++ b/src/Interfaces/MiddlewareInterface.php
@@ -11,6 +11,6 @@ interface MiddlewareInterface
     public function __invoke(
         ServerRequestInterface $request,
         ResponseInterface $response,
-        \Closure $next = null
+        callable $next = null
     ): ResponseInterface;
 }
\ No newline at end of file
diff --git a/src/Middleware.php b/src/Middleware.php
index fb389ee..4ca6c09 100644
--- a/src/Middleware.php
+++ b/src/Middleware.php
@@ -14,7 +14,7 @@ trait Middleware
      */
     protected $top;
 
-    protected function addMiddleware(callable $callable)
+    public function addMiddleware(callable $callable)
     {
         if (is_null($this->top)) {
             $this->initStack();