diff --git a/.gitattributes b/.gitattributes
index fc86054..46cbe14 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1,4 +1,5 @@
 # Files that composer should ignore when downloading package
+/.*  export-ignore
 /Dockerfile  export-ignore
 /Makefile  export-ignore
 /README.md  export-ignore
diff --git a/.gitignore b/.gitignore
index 405484d..4c6bc4c 100644
--- a/.gitignore
+++ b/.gitignore
@@ -1,3 +1,4 @@
 /var
 /vendor
 /composer.lock
+.*.cache
diff --git a/.php-cs-fixer.php b/.php-cs-fixer.php
new file mode 100644
index 0000000..0d154ff
--- /dev/null
+++ b/.php-cs-fixer.php
@@ -0,0 +1,14 @@
+<?php
+
+return (new PhpCsFixer\Config())
+    ->setRules([
+        '@Symfony' => true,
+        '@Symfony:risky' => true,
+    ])
+    ->setRiskyAllowed(true)
+    ->setFinder(
+        PhpCsFixer\Finder::create()
+            ->in(__DIR__.'/src')
+            ->in(__DIR__.'/tests')
+    )
+;
diff --git a/Dockerfile b/Dockerfile
index be3eece..e6eb5d6 100644
--- a/Dockerfile
+++ b/Dockerfile
@@ -2,4 +2,7 @@ FROM php:8.1-fpm-alpine
 
 RUN curl -s https://getcomposer.org/installer | php -- --install-dir=/usr/local/bin --filename=composer
 
+RUN curl -s https://cs.symfony.com/download/php-cs-fixer-v3.phar -o /usr/local/bin/php-cs-fixer \
+  && chmod +x /usr/local/bin/php-cs-fixer
+
 WORKDIR /app
diff --git a/Makefile b/Makefile
index c469bcc..538b38e 100644
--- a/Makefile
+++ b/Makefile
@@ -1,6 +1,9 @@
 clear-cache:
 	rm -rf var
 
+php-cs-fixer: clear-cache
+	docker-compose run --rm -T php /usr/local/bin/php-cs-fixer fix --no-interaction --verbose --dry-run
+
 phpunit: clear-cache
 	docker-compose run --rm -T php /usr/local/bin/php /app/vendor/bin/phpunit
 
diff --git a/README.md b/README.md
index ea296f1..11510ef 100644
--- a/README.md
+++ b/README.md
@@ -45,10 +45,10 @@ public function indexAction(Request $request)
 
 Per default request content will be transformed only for requests with content type `json` or `jsonld`.
 
-but you can stil configure it with
+But you can stil configure it with
 
 ``` yaml
-# serices.yaml
+# config/serices.yaml
 
 json_request:
     content_types:
diff --git a/composer.json b/composer.json
index 8d04206..fc7a90c 100644
--- a/composer.json
+++ b/composer.json
@@ -26,8 +26,13 @@
         "phpunit/php-code-coverage": "^9.2",
         "phpunit/phpunit": "^9.5",
         "symfony/browser-kit": "^5.2 || ^6.0",
+        "symfony/phpunit-bridge": "^5.2 || ^6.2",
         "symfony/yaml": "^5.2 || ^6.0"
     },
+    "scripts": {
+        "csfixer": "php-cs-fixer fix --verbose --dry-run --diff",
+        "csfixer-fix": "php-cs-fixer fix --verbose"
+    },
     "config": {
         "preferred-install": "dist",
         "sort-packages": true
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 8a80d2e..16d882e 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -22,6 +22,10 @@
         </testsuite>
     </testsuites>
 
+    <listeners>
+        <listener class="Symfony\Bridge\PhpUnit\SymfonyTestsListener" />
+    </listeners>
+
     <coverage>
         <include>
             <directory>src</directory>
diff --git a/src/DependencyInjection/Configuration.php b/src/DependencyInjection/Configuration.php
index 9d86ebb..ece96ef 100644
--- a/src/DependencyInjection/Configuration.php
+++ b/src/DependencyInjection/Configuration.php
@@ -1,4 +1,6 @@
-<?php declare(strict_types=1);
+<?php
+
+declare(strict_types=1);
 
 namespace SymfonyBundles\JsonRequestBundle\DependencyInjection;
 
diff --git a/src/DependencyInjection/JsonRequestExtension.php b/src/DependencyInjection/JsonRequestExtension.php
index 930e60e..818bf8f 100644
--- a/src/DependencyInjection/JsonRequestExtension.php
+++ b/src/DependencyInjection/JsonRequestExtension.php
@@ -1,11 +1,13 @@
-<?php declare(strict_types=1);
+<?php
+
+declare(strict_types=1);
 
 namespace SymfonyBundles\JsonRequestBundle\DependencyInjection;
 
 use Symfony\Component\Config\Definition\Processor;
-use Symfony\Component\HttpKernel\KernelEvents;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Extension\Extension;
+use Symfony\Component\HttpKernel\KernelEvents;
 use SymfonyBundles\JsonRequestBundle\EventListener\RequestTransformerListener;
 
 final class JsonRequestExtension extends Extension
diff --git a/src/EventListener/RequestTransformerListener.php b/src/EventListener/RequestTransformerListener.php
index b87870d..761c8c6 100644
--- a/src/EventListener/RequestTransformerListener.php
+++ b/src/EventListener/RequestTransformerListener.php
@@ -1,10 +1,12 @@
-<?php declare(strict_types=1);
+<?php
+
+declare(strict_types=1);
 
 namespace SymfonyBundles\JsonRequestBundle\EventListener;
 
+use Symfony\Component\HttpFoundation\JsonResponse;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
-use Symfony\Component\HttpFoundation\JsonResponse;
 use Symfony\Component\HttpKernel\Event\RequestEvent;
 
 final class RequestTransformerListener
@@ -25,7 +27,7 @@ public function onKernelRequest(RequestEvent $event): void
         }
 
         try {
-            $data = \json_decode((string) $request->getContent(), true, 512, \JSON_THROW_ON_ERROR);
+            $data = json_decode((string) $request->getContent(), true, 512, \JSON_THROW_ON_ERROR);
 
             if (\is_array($data)) {
                 $request->request->replace($data);
@@ -37,6 +39,8 @@ public function onKernelRequest(RequestEvent $event): void
 
     private function supports(Request $request): bool
     {
-        return in_array($request->getContentType(), $this->contentTypes, true) && $request->getContent();
+        $contentType = method_exists($request, 'getContentTypeFormat') ? $request->getContentTypeFormat() : $request->getContentType();
+
+        return \in_array($contentType, $this->contentTypes, true) && $request->getContent();
     }
 }
diff --git a/src/JsonRequestBundle.php b/src/JsonRequestBundle.php
index a04e224..a55d9c7 100644
--- a/src/JsonRequestBundle.php
+++ b/src/JsonRequestBundle.php
@@ -1,4 +1,6 @@
-<?php declare(strict_types=1);
+<?php
+
+declare(strict_types=1);
 
 namespace SymfonyBundles\JsonRequestBundle;
 
diff --git a/tests/Controller/ExampleControllerTest.php b/tests/Controller/ExampleControllerTest.php
index 9aca38b..e5b188e 100644
--- a/tests/Controller/ExampleControllerTest.php
+++ b/tests/Controller/ExampleControllerTest.php
@@ -1,16 +1,18 @@
-<?php declare(strict_types=1);
+<?php
+
+declare(strict_types=1);
 
 namespace SymfonyBundles\JsonRequestBundle\Tests\Controller;
 
+use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
-use Symfony\Bundle\FrameworkBundle\Test\WebTestCase;
 
 final class ExampleControllerTest extends WebTestCase
 {
     public function testTransformRequest(): void
     {
-        $body = \json_encode(['foo' => 'baz']);
+        $body = json_encode(['foo' => 'baz']);
 
         $response = $this->sendRequest($body);
 
@@ -19,7 +21,7 @@ public function testTransformRequest(): void
 
     public function testTransformJsonldRequest(): void
     {
-        $body = \json_encode(['foo' => 'baz']);
+        $body = json_encode(['foo' => 'baz']);
 
         $response = $this->sendRequest($body, 'application/ld+json');
 
@@ -28,7 +30,7 @@ public function testTransformJsonldRequest(): void
 
     public function testTransformSoneOtherTypeRequest(): void
     {
-        $body = \json_encode(['foo' => 'baz']);
+        $body = json_encode(['foo' => 'baz']);
 
         // add content type. they are stored in static Request::formats variable
         (new Request())->setFormat('someother', 'application/some+other+type');
@@ -48,7 +50,7 @@ public function testInvalidBody(): void
 
     public function testInvalidContentType(): void
     {
-        $body = \json_encode(['foo' => 'baz']);
+        $body = json_encode(['foo' => 'baz']);
 
         $response = $this->sendRequest($body, 'application/javascript');
 
@@ -56,10 +58,7 @@ public function testInvalidContentType(): void
     }
 
     /**
-     * @param mixed  $body
-     * @param string $contentType
-     *
-     * @return Response
+     * @param mixed $body
      */
     private function sendRequest($body, string $contentType = 'application/json'): Response
     {
diff --git a/tests/DependencyInjectionTest.php b/tests/DependencyInjectionTest.php
index bf24a51..009a4c1 100644
--- a/tests/DependencyInjectionTest.php
+++ b/tests/DependencyInjectionTest.php
@@ -1,4 +1,6 @@
-<?php declare(strict_types=1);
+<?php
+
+declare(strict_types=1);
 
 namespace SymfonyBundles\JsonRequestBundle\Tests;
 
@@ -100,7 +102,7 @@ public function testContentTypesExpectedScalarArrayGiven(): void
         $extension->load([$config], $this->containerBuilder);
     }
 
-    private function assertContentTypes(array $expected)
+    private function assertContentTypes(array $expected): void
     {
         $listenerDefinition = $this->containerBuilder->findDefinition(RequestTransformerListener::class);
         $this->assertEquals($expected, $listenerDefinition->getArgument(0));
diff --git a/tests/EventListener/RequestTransformerListenerTest.php b/tests/EventListener/RequestTransformerListenerTest.php
index 3c0a623..0244b37 100644
--- a/tests/EventListener/RequestTransformerListenerTest.php
+++ b/tests/EventListener/RequestTransformerListenerTest.php
@@ -12,8 +12,17 @@
 
 class RequestTransformerListenerTest extends TestCase
 {
+    private static string $getContentTypeFormat = 'getContentTypeFormat';
+
     private RequestTransformerListener $listener;
 
+    public static function setUpBeforeClass(): void
+    {
+        if (!method_exists(Request::class, 'getContentTypeFormat')) {
+            self::$getContentTypeFormat = 'getContentType';
+        }
+    }
+
     protected function setUp(): void
     {
         $this->listener = new RequestTransformerListener(['json']);
@@ -23,7 +32,7 @@ public function testOnKernelRequestWithInvalidJson(): void
     {
         $request = $this->createMock(Request::class);
         $request->method('getContent')->willReturn('{"test": "val}');
-        $request->method('getContentType')->willReturn("json");
+        $request->method(self::$getContentTypeFormat)->willReturn('json');
 
         $requestEvent = $this->createMock(RequestEvent::class);
         $requestEvent->method('getRequest')->willReturn($request);
@@ -31,6 +40,7 @@ public function testOnKernelRequestWithInvalidJson(): void
         $requestEvent->expects($this->once())->method('setResponse')->willReturnCallback(function ($resp) {
             $this->assertInstanceOf(JsonResponse::class, $resp);
             $this->assertEquals(Response::HTTP_BAD_REQUEST, $resp->getStatusCode());
+            $this->assertIsString($resp->getContent());
             $this->assertJson($resp->getContent());
         });
 
@@ -43,7 +53,7 @@ public function testOnKernelRequestWithValidJson(): void
 
         $request = $this->createMock(Request::class);
         $request->method('getContent')->willReturn('{"test": "val"}');
-        $request->method('getContentType')->willReturn('json');
+        $request->method(self::$getContentTypeFormat)->willReturn('json');
         $request->request = $inputBag;
 
         $requestEvent = $this->createMock(RequestEvent::class);
diff --git a/tests/Fixture/App/Controller/ExampleController.php b/tests/Fixture/App/Controller/ExampleController.php
index 098a4ee..fa420e4 100644
--- a/tests/Fixture/App/Controller/ExampleController.php
+++ b/tests/Fixture/App/Controller/ExampleController.php
@@ -1,13 +1,14 @@
-<?php declare(strict_types=1);
+<?php
+
+declare(strict_types=1);
 
 namespace SymfonyBundles\JsonRequestBundle\Tests\Fixture\App\Controller;
 
-use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\JsonResponse;
+use Symfony\Component\HttpFoundation\Request;
 
 final class ExampleController
 {
-
     public function index(Request $request): JsonResponse
     {
         return new JsonResponse($request->request->all());
diff --git a/tests/Fixture/App/Kernel.php b/tests/Fixture/App/Kernel.php
index 74d2d2b..8fdd404 100644
--- a/tests/Fixture/App/Kernel.php
+++ b/tests/Fixture/App/Kernel.php
@@ -1,11 +1,13 @@
-<?php declare(strict_types=1);
+<?php
+
+declare(strict_types=1);
 
 namespace SymfonyBundles\JsonRequestBundle\Tests\Fixture\App;
 
-use Symfony\Component\HttpKernel\Kernel as BaseKernel;
 use Symfony\Bundle\FrameworkBundle\Kernel\MicroKernelTrait;
-use Symfony\Component\Routing\Loader\Configurator\RoutingConfigurator;
 use Symfony\Component\DependencyInjection\Loader\Configurator\ContainerConfigurator;
+use Symfony\Component\HttpKernel\Kernel as BaseKernel;
+use Symfony\Component\Routing\Loader\Configurator\RoutingConfigurator;
 
 final class Kernel extends BaseKernel
 {