diff --git a/src/PropertyDescriber/PropertyDescriber.php b/src/PropertyDescriber/PropertyDescriber.php
index 03793ae1b..d18e480b0 100644
--- a/src/PropertyDescriber/PropertyDescriber.php
+++ b/src/PropertyDescriber/PropertyDescriber.php
@@ -71,11 +71,6 @@ private function getHash(array $types): string
     private function getPropertyDescriber(array $types, array $context): ?PropertyDescriberInterface
     {
         foreach ($this->propertyDescribers as $propertyDescriber) {
-            /* BC layer for Symfony < 6.3 @see https://symfony.com/doc/6.3/service_container/tags.html#reference-tagged-services */
-            if ($propertyDescriber instanceof self) {
-                continue;
-            }
-
             // Prevent infinite recursion
             if (\array_key_exists($this->getHash($types), $this->called)) {
                 if (\in_array($propertyDescriber, $this->called[$this->getHash($types)], true)) {
diff --git a/tests/Functional/ControllerTest.php b/tests/Functional/ControllerTest.php
index 01e6e7276..b09da5001 100644
--- a/tests/Functional/ControllerTest.php
+++ b/tests/Functional/ControllerTest.php
@@ -79,12 +79,10 @@ public function testControllers(?array $controller, ?string $fixtureName = null,
 
     public static function provideAttributeTestCases(): \Generator
     {
-        $type = Kernel::MAJOR_VERSION === 5 ? 'annotation' : 'attribute';
-
         yield 'Promoted properties defaults attributes' => [
             [
                 'name' => 'PromotedPropertiesController81',
-                'type' => $type,
+                'type' => 'attribute',
             ],
             'PromotedPropertiesDefaults',
             [],
@@ -94,78 +92,78 @@ public static function provideAttributeTestCases(): \Generator
         yield 'JMS model opt out' => [
             [
                 'name' => 'JmsOptOutController',
-                'type' => $type,
+                'type' => 'attribute',
             ],
             'JmsOptOutController',
             [new JMSSerializerBundle()],
             [__DIR__.'/Configs/JMS.yaml'],
         ];
 
-        if (version_compare(Kernel::VERSION, '6.3.0', '>=')) {
-            yield 'https://github.com/nelmio/NelmioApiDocBundle/issues/2209' => [
-                [
-                    'name' => 'Controller2209',
-                    'type' => $type,
-                ],
-            ];
-            yield 'MapQueryString' => [
-                [
-                    'name' => 'MapQueryStringController',
-                    'type' => $type,
-                    null,
-                    [],
-                    [__DIR__.'/Configs/EnableSerializer.yaml'],
-                ],
-            ];
-            yield 'https://github.com/nelmio/NelmioApiDocBundle/issues/2191' => [
-                [
-                    'name' => 'MapQueryStringController',
-                    'type' => $type,
-                ],
-                'MapQueryStringCleanupComponents',
-                [],
-                [__DIR__.'/Configs/CleanUnusedComponentsProcessor.yaml', __DIR__.'/Configs/EnableSerializer.yaml'],
-            ];
-
-            yield 'operationId must always be generated' => [
-                [
-                    'name' => 'OperationIdController',
-                    'type' => $type,
-                ],
-            ];
-
-            yield 'Symfony 6.3 MapQueryParameter attribute' => [
-                [
-                    'name' => 'MapQueryParameterController',
-                    'type' => $type,
-                ],
-            ];
+        yield 'https://github.com/nelmio/NelmioApiDocBundle/issues/2209' => [
+            [
+                'name' => 'Controller2209',
+                'type' => 'attribute',
+            ],
+        ];
 
-            yield 'Symfony 6.3 MapRequestPayload attribute' => [
-                [
-                    'name' => 'MapRequestPayloadController',
-                    'type' => $type,
-                ],
+        yield 'MapQueryString' => [
+            [
+                'name' => 'MapQueryStringController',
+                'type' => 'attribute',
                 null,
                 [],
                 [__DIR__.'/Configs/EnableSerializer.yaml'],
-            ];
+            ],
+        ];
+
+        yield 'https://github.com/nelmio/NelmioApiDocBundle/issues/2191' => [
+            [
+                'name' => 'MapQueryStringController',
+                'type' => 'attribute',
+            ],
+            'MapQueryStringCleanupComponents',
+            [],
+            [__DIR__.'/Configs/CleanUnusedComponentsProcessor.yaml', __DIR__.'/Configs/EnableSerializer.yaml'],
+        ];
+
+        yield 'operationId must always be generated' => [
+            [
+                'name' => 'OperationIdController',
+                'type' => 'attribute',
+            ],
+        ];
+
+        yield 'Symfony 6.3 MapQueryParameter attribute' => [
+            [
+                'name' => 'MapQueryParameterController',
+                'type' => 'attribute',
+            ],
+        ];
+
+        yield 'Symfony 6.3 MapRequestPayload attribute' => [
+            [
+                'name' => 'MapRequestPayloadController',
+                'type' => 'attribute',
+            ],
+            null,
+            [],
+            [__DIR__.'/Configs/EnableSerializer.yaml'],
+        ];
 
-            yield 'Create top level Tag from Tag attribute' => [
+        yield 'Create top level Tag from Tag attribute' => [
+            [
+                'name' => 'OpenApiTagController',
+                'type' => 'attribute',
+            ],
+        ];
+
+        if (property_exists(MapRequestPayload::class, 'type')) {
+            yield 'Symfony 7.1 MapRequestPayload array type' => [
                 [
-                    'name' => 'OpenApiTagController',
-                    'type' => $type,
+                    'name' => 'MapRequestPayloadArray',
+                    'type' => 'attribute',
                 ],
             ];
-
-            if (property_exists(MapRequestPayload::class, 'type')) {
-                yield 'Symfony 7.1 MapRequestPayload array type' => [
-                    [
-                        'name' => 'MapRequestPayloadArray',
-                        'type' => $type,
-                    ],
-                ];
-            }
         }
     }
 
diff --git a/tests/Functional/Entity/RangeInteger.php b/tests/Functional/Entity/RangeInteger.php
index c41488d6f..a3c4b1527 100644
--- a/tests/Functional/Entity/RangeInteger.php
+++ b/tests/Functional/Entity/RangeInteger.php
@@ -13,8 +13,6 @@
 
 namespace Nelmio\ApiDocBundle\Tests\Functional\Entity;
 
-use Symfony\Component\HttpKernel\Kernel;
-
 trait RangeIntegerTrait
 {
     /**
@@ -38,24 +36,17 @@ trait RangeIntegerTrait
     public $nullableRangeInt;
 }
 
-if (version_compare(Kernel::VERSION, '6.1', '>=')) {
-    class RangeInteger
-    {
-        use RangeIntegerTrait;
-
-        /**
-         * @var positive-int
-         */
-        public $positiveInt;
-
-        /**
-         * @var negative-int
-         */
-        public $negativeInt;
-    }
-} else {
-    class RangeInteger
-    {
-        use RangeIntegerTrait;
-    }
+class RangeInteger
+{
+    use RangeIntegerTrait;
+
+    /**
+     * @var positive-int
+     */
+    public $positiveInt;
+
+    /**
+     * @var negative-int
+     */
+    public $negativeInt;
 }
diff --git a/tests/Functional/FOSRestTest.php b/tests/Functional/FOSRestTest.php
index 205d18d55..5c449947b 100644
--- a/tests/Functional/FOSRestTest.php
+++ b/tests/Functional/FOSRestTest.php
@@ -80,10 +80,8 @@ public function testFOSRestAction(string $route): void
 
     public static function provideRoute(): \Generator
     {
-        yield 'Annotations' => ['/api/fosrest'];
+        yield ['/api/fosrest'];
 
-        if (TestKernel::isAttributesAvailable()) {
-            yield 'Attributes' => ['/api/fosrest_attributes'];
-        }
+        yield ['/api/fosrest_attributes'];
     }
 }
diff --git a/tests/Functional/FunctionalTest.php b/tests/Functional/FunctionalTest.php
index 2f1481c37..455d040b8 100644
--- a/tests/Functional/FunctionalTest.php
+++ b/tests/Functional/FunctionalTest.php
@@ -16,7 +16,6 @@
 use OpenApi\Attributes as OAAttributes;
 use OpenApi\Generator;
 use PHPUnit\Framework\Attributes\DataProvider;
-use Symfony\Component\HttpKernel\Kernel;
 
 class FunctionalTest extends WebTestCase
 {
@@ -1234,19 +1233,17 @@ public function testRangeIntegers(): void
             'type' => 'object',
         ];
 
-        if (version_compare(Kernel::VERSION, '6.1', '>=')) {
-            array_unshift($expected['required'], 'positiveInt', 'negativeInt');
-            $expected['properties'] += [
-                'positiveInt' => [
-                    'type' => 'integer',
-                    'minimum' => 1,
-                ],
-                'negativeInt' => [
-                    'type' => 'integer',
-                    'maximum' => -1,
-                ],
-            ];
-        }
+        array_unshift($expected['required'], 'positiveInt', 'negativeInt');
+        $expected['properties'] += [
+            'positiveInt' => [
+                'type' => 'integer',
+                'minimum' => 1,
+            ],
+            'negativeInt' => [
+                'type' => 'integer',
+                'maximum' => -1,
+            ],
+        ];
 
         self::assertEquals($expected, json_decode($this->getModel('RangeInteger')->toJson(), true));
     }
diff --git a/tests/Functional/JMSFunctionalTest.php b/tests/Functional/JMSFunctionalTest.php
index a8834fef4..73dc49eb7 100644
--- a/tests/Functional/JMSFunctionalTest.php
+++ b/tests/Functional/JMSFunctionalTest.php
@@ -380,11 +380,6 @@ public function testEnumSupport(): void
             ],
         ], json_decode($this->getModel('ArticleType81')->toJson(), true));
 
-        if (TestKernel::isAnnotationsAvailable()) {
-            // Further tests have only been defined with attributes
-            return;
-        }
-
         self::assertEquals([
             'schema' => 'ArticleType812',
             'type' => 'string',
diff --git a/tests/Functional/ModelDescriber/ObjectModelDescriberTest.php b/tests/Functional/ModelDescriber/ObjectModelDescriberTest.php
index c1a2d0c84..ab0b435d2 100644
--- a/tests/Functional/ModelDescriber/ObjectModelDescriberTest.php
+++ b/tests/Functional/ModelDescriber/ObjectModelDescriberTest.php
@@ -18,7 +18,6 @@
 use Nelmio\ApiDocBundle\Tests\Functional\WebTestCase;
 use OpenApi\Annotations as OA;
 use OpenApi\Annotations\OpenApi;
-use Symfony\Component\HttpKernel\Kernel;
 use Symfony\Component\PropertyInfo\Type as LegacyType;
 
 class ObjectModelDescriberTest extends WebTestCase
@@ -92,11 +91,9 @@ public static function provideFixtures(): \Generator
             Fixtures\ClassWithObject::class,
         ];
 
-        if (\PHP_VERSION_ID >= 80100) {
-            yield [
-                Fixtures\ClassWithIntersection::class,
-            ];
-        }
+        yield [
+            Fixtures\ClassWithIntersection::class,
+        ];
 
         yield [
             Fixtures\DateTimeClass::class,
@@ -106,11 +103,9 @@ public static function provideFixtures(): \Generator
             Fixtures\UuidClass::class,
         ];
 
-        if (version_compare(Kernel::VERSION, '6.4.0', '>=')) {
-            yield [
-                Fixtures\UuidClass7And8::class,
-            ];
-        }
+        yield [
+            Fixtures\UuidClass7And8::class,
+        ];
 
         yield [
             Fixtures\Refs::class,
diff --git a/tests/Functional/Resources/routes-attributes.yaml b/tests/Functional/Resources/routes-attributes.yaml
deleted file mode 100644
index 7d131ab52..000000000
--- a/tests/Functional/Resources/routes-attributes.yaml
+++ /dev/null
@@ -1,46 +0,0 @@
-# Resources
-test:
-    resource: ../Controller/TestController.php
-    type: attribute
-
-api:
-    resource: ../Controller/ApiController.php
-    type: attribute
-
-class_api:
-    resource: ../Controller/ClassApiController.php
-    type: attribute
-  
-undocumented:
-    resource: ../Controller/UndocumentedController.php
-    type: attribute
-  
-invokable:
-    resource: ../Controller/InvokableController.php
-    type: attribute
-  
-api_platform:
-    resource: .
-    prefix: /api
-    type: api_platform
-
-# Controllers
-doc_area:
-    path: /{area}/docs
-    controller: nelmio_api_doc.controller.swagger_ui
-    defaults: 
-        area: default
-
-redocly_doc_area:
-    path: /{area}/redocly/docs
-    controller: nelmio_api_doc.controller.redocly
-    defaults:
-        area: default
-
-doc_json:
-    path: /{area}/docs.json
-    controller: nelmio_api_doc.controller.swagger_json
-
-doc_yaml:
-    path: /{area}/docs.yaml
-    controller: nelmio_api_doc.controller.swagger_yaml
diff --git a/tests/Functional/Resources/routes.yaml b/tests/Functional/Resources/routes.yaml
index 469d84bc0..f221309fe 100644
--- a/tests/Functional/Resources/routes.yaml
+++ b/tests/Functional/Resources/routes.yaml
@@ -1,24 +1,24 @@
 # Resources
 test:
     resource: ../Controller/TestController.php
-    type: annotation
+    type: attribute
 
 api:
     resource: ../Controller/ApiController.php
-    type: annotation
+    type: attribute
 
 class_api:
     resource: ../Controller/ClassApiController.php
-    type: annotation
-  
+    type: attribute
+
 undocumented:
     resource: ../Controller/UndocumentedController.php
-    type: annotation
-  
+    type: attribute
+
 invokable:
     resource: ../Controller/InvokableController.php
-    type: annotation
-  
+    type: attribute
+
 api_platform:
     resource: .
     prefix: /api
@@ -28,7 +28,7 @@ api_platform:
 doc_area:
     path: /{area}/docs
     controller: nelmio_api_doc.controller.swagger_ui
-    defaults: 
+    defaults:
         area: default
 
 redocly_doc_area:
diff --git a/tests/Functional/TestKernel.php b/tests/Functional/TestKernel.php
index 0533f5416..c68f07f9b 100644
--- a/tests/Functional/TestKernel.php
+++ b/tests/Functional/TestKernel.php
@@ -79,22 +79,18 @@ public function registerBundles(): iterable
 
     protected function configureRoutes(RoutingConfigurator $routes): void
     {
-        if (self::isAnnotationsAvailable()) {
-            $routes->withPath('/')->import(__DIR__.'/Resources/routes.yaml', 'yaml');
-        } else {
-            $routes->withPath('/')->import(__DIR__.'/Resources/routes-attributes.yaml', 'yaml');
-        }
+        $routes->withPath('/')->import(__DIR__.'/Resources/routes.yaml', 'yaml');
 
         if (self::USE_JMS === $this->flag || self::USE_BAZINGA === $this->flag) {
-            $routes->withPath('/')->import(__DIR__.'/Controller/JMSController.php', self::isAnnotationsAvailable() ? 'annotation' : 'attribute');
+            $routes->withPath('/')->import(__DIR__.'/Controller/JMSController.php', 'attribute');
         }
 
         if (self::USE_BAZINGA === $this->flag) {
-            $routes->withPath('/')->import(__DIR__.'/Controller/BazingaTypedController.php', self::isAnnotationsAvailable() ? 'annotation' : 'attribute');
+            $routes->withPath('/')->import(__DIR__.'/Controller/BazingaTypedController.php', 'attribute');
         }
 
         if (self::USE_FOSREST === $this->flag) {
-            $routes->withPath('/')->import(__DIR__.'/Controller/FOSRestController.php', self::isAnnotationsAvailable() ? 'annotation' : 'attribute');
+            $routes->withPath('/')->import(__DIR__.'/Controller/FOSRestController.php', 'attribute');
         }
     }
 
@@ -106,11 +102,8 @@ protected function configureContainer(ContainerBuilder $c, LoaderInterface $load
             'test' => null,
             'validation' => null,
             'form' => null,
-            'serializer' => (
-                Kernel::MAJOR_VERSION < 7
-                    ? ['enable_annotations' => true]
-                    : []
-            ) + [
+            'serializer' => [
+                'enable_attributes' => true,
                 'mapping' => [
                     'paths' => [__DIR__.'/Resources/serializer/'],
                 ],
@@ -320,22 +313,4 @@ public function getLogDir(): string
     {
         return parent::getLogDir().'/'.$this->flag;
     }
-
-    public static function isAnnotationsAvailable(): bool
-    {
-        if (Kernel::MAJOR_VERSION <= 5) {
-            return true;
-        }
-
-        if (Kernel::MAJOR_VERSION >= 7) {
-            return false;
-        }
-
-        return false;
-    }
-
-    public static function isAttributesAvailable(): bool
-    {
-        return true;
-    }
 }
diff --git a/tests/Routing/FilteredRouteCollectionBuilderTest.php b/tests/Routing/FilteredRouteCollectionBuilderTest.php
index 9bca7b5ed..36bc78321 100644
--- a/tests/Routing/FilteredRouteCollectionBuilderTest.php
+++ b/tests/Routing/FilteredRouteCollectionBuilderTest.php
@@ -140,9 +140,7 @@ public static function getMatchingRoutes(): \Generator
             ['r10', new Route('/api/areas/new'), ['path_patterns' => ['^/api']]],
         ];
 
-        if (\PHP_VERSION_ID < 80000) {
-            yield ['r10', new Route('/api/areas_attributes/new'), ['path_patterns' => ['^/api']]];
-        }
+        yield ['r10', new Route('/api/areas_attributes/new'), ['path_patterns' => ['^/api']]];
     }
 
     /**