diff --git a/src/MockedClient/HandlerBuilder.php b/src/MockedClient/HandlerBuilder.php
index 481512b..ef1897e 100644
--- a/src/MockedClient/HandlerBuilder.php
+++ b/src/MockedClient/HandlerBuilder.php
@@ -6,10 +6,11 @@
 
 use DoppioGancio\MockedClient\Exception\RouteNotFound;
 use DoppioGancio\MockedClient\Route\Route;
+use GuzzleHttp\Promise\FulfilledPromise;
+use GuzzleHttp\Promise\PromiseInterface;
 use League\Route\Http\Exception\NotFoundException;
 use League\Route\Router;
 use Psr\Http\Message\RequestInterface;
-use Psr\Http\Message\ResponseInterface;
 use Psr\Http\Message\ServerRequestFactoryInterface;
 use Psr\Log\LoggerInterface;
 use Psr\Log\NullLogger;
@@ -39,11 +40,11 @@ public function addRoute(Route $route): self
     }
 
     /**
-     * @return callable(RequestInterface): ResponseInterface
+     * @return callable(RequestInterface): PromiseInterface
      */
     public function build(): callable
     {
-        return function (RequestInterface $request): ResponseInterface {
+        return function (RequestInterface $request): PromiseInterface {
             $uri = $request->getUri()
                 ->withScheme('')
                 ->withHost('')
@@ -90,7 +91,7 @@ public function build(): callable
                     ]
                 );
 
-                return $response;
+                return new FulfilledPromise($response);
             } catch (NotFoundException $e) {
                 $this->logError($e, $request);
 
diff --git a/src/MockedClient/MockedGuzzleClientBuilder.php b/src/MockedClient/MockedGuzzleClientBuilder.php
index f5af869..b18b4ef 100644
--- a/src/MockedClient/MockedGuzzleClientBuilder.php
+++ b/src/MockedClient/MockedGuzzleClientBuilder.php
@@ -5,24 +5,15 @@
 namespace DoppioGancio\MockedClient;
 
 use GuzzleHttp\Client;
-use GuzzleHttp\Exception\ClientException;
-use GuzzleHttp\Exception\ServerException;
 use GuzzleHttp\HandlerStack;
 use GuzzleHttp\MessageFormatter;
 use GuzzleHttp\Middleware;
-use GuzzleHttp\Promise\FulfilledPromise;
-use GuzzleHttp\Promise\PromiseInterface;
-use GuzzleHttp\Psr7\Response;
-use Psr\Http\Message\RequestInterface;
 use Psr\Log\LoggerInterface;
 use Psr\Log\NullLogger;
 
-use function assert;
-
 class MockedGuzzleClientBuilder
 {
     private HandlerBuilder $handlerBuilder;
-    private LoggerInterface $logger;
 
     /** @var array<callable>  */
     private array $middlewares = [];
@@ -32,7 +23,10 @@ public function __construct(
         ?LoggerInterface $logger = null
     ) {
         $this->handlerBuilder = $handlerBuilder;
-        $this->logger         = $logger ?? new NullLogger();
+        $this->addMiddleware(Middleware::log(
+            $logger ?? new NullLogger(),
+            new MessageFormatter()
+        ));
     }
 
     public function addMiddleware(callable $middleware): self
@@ -42,43 +36,19 @@ public function addMiddleware(callable $middleware): self
         return $this;
     }
 
-    public function build(): Client
+    /** @param array<string,mixed> $options */
+    public function build(array $options = []): Client
     {
         $handler = $this->handlerBuilder->build();
 
-        $callback = static function (RequestInterface $request, $options) use ($handler): PromiseInterface {
-            $response = $handler($request);
-            assert($response instanceof Response);
-            if ($response->getStatusCode() >= 400 && $response->getStatusCode() < 500) {
-                throw new ClientException(
-                    $response->getBody()->getContents(),
-                    $request,
-                    $response
-                );
-            }
-
-            if ($response->getStatusCode() >= 500 && $response->getStatusCode() < 600) {
-                throw new ServerException(
-                    $response->getBody()->getContents(),
-                    $request,
-                    $response
-                );
-            }
-
-            return new FulfilledPromise($response);
-        };
-
-        $handlerStack = new HandlerStack($callback);
-
-        $handlerStack->push(Middleware::log(
-            $this->logger,
-            new MessageFormatter()
-        ));
+        $handlerStack = HandlerStack::create($handler);
 
         foreach ($this->middlewares as $middleware) {
             $handlerStack->push($middleware);
         }
 
-        return new Client(['handler' => $handlerStack]);
+        $options['handler'] = $handlerStack;
+
+        return new Client($options);
     }
 }
diff --git a/tests/ClientBuilderTest.php b/tests/ClientBuilderTest.php
index 97da84f..883b49a 100644
--- a/tests/ClientBuilderTest.php
+++ b/tests/ClientBuilderTest.php
@@ -81,8 +81,12 @@ public function testRouteNotFound(): void
 
     public function testClientWithFullUrl(): void
     {
-        $response = $this->getMockedClient()->request('GET', 'http://user:password@localhost:8099/country/?page=1&code=it');
-        $body     = (string) $response->getBody();
+        $response = $this->getMockedClient()->request(
+            'GET',
+            'http://user:password@localhost:8099/country/?page=1&code=it'
+        );
+
+        $body = (string) $response->getBody();
         $this->assertEquals('{"id":"+39","code":"IT","name":"Italy"}', $body);
     }