diff --git a/.github/workflows/ci.yml b/.github/workflows/ci.yml
index 9c646d9..640398e 100644
--- a/.github/workflows/ci.yml
+++ b/.github/workflows/ci.yml
@@ -6,36 +6,36 @@ on:
     - cron: "0 0 * * *"
 
 jobs:
-  php82:
-    name: PHP 8.2
+  php83:
+    name: PHP 8.3
     runs-on: ubuntu-24.04
     steps:
       - name: checkout
         uses: actions/checkout@v4
       - name: composer test
-        uses: docker://ghcr.io/chubbyphp/ci-php82:latest
+        uses: docker://ghcr.io/chubbyphp/ci-php83:latest
         env:
           COVERALLS_REPO_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           STRYKER_DASHBOARD_API_KEY: ${{ secrets.STRYKER_DASHBOARD_API_KEY }}
-  php83:
-    name: PHP 8.3
+  php84:
+    name: PHP 8.4
     runs-on: ubuntu-24.04
     steps:
       - name: checkout
         uses: actions/checkout@v4
       - name: composer test
-        uses: docker://ghcr.io/chubbyphp/ci-php83:latest
+        uses: docker://ghcr.io/chubbyphp/ci-php84:latest
         env:
           COVERALLS_REPO_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           STRYKER_DASHBOARD_API_KEY: ${{ secrets.STRYKER_DASHBOARD_API_KEY }}
-  php84:
-    name: PHP 8.4
+  php85:
+    name: PHP 8.5
     runs-on: ubuntu-24.04
     steps:
       - name: checkout
         uses: actions/checkout@v4
       - name: composer test
-        uses: docker://ghcr.io/chubbyphp/ci-php84:latest
+        uses: docker://ghcr.io/chubbyphp/ci-php85:latest
         env:
           COVERALLS_REPO_TOKEN: ${{ secrets.GITHUB_TOKEN }}
           STRYKER_DASHBOARD_API_KEY: ${{ secrets.STRYKER_DASHBOARD_API_KEY }}
diff --git a/.php-cs-fixer.php b/.php-cs-fixer.php
index 19ba81e..85172b8 100644
--- a/.php-cs-fixer.php
+++ b/.php-cs-fixer.php
@@ -12,10 +12,8 @@
 /** @var array $config */
 $config = require __DIR__ . '/vendor/chubbyphp/chubbyphp-dev-helper/phpcs.php';
 
-// drop onces code is >= 8.0
-unset($config['rules']['phpdoc_to_return_type']);
-
 return (new PhpCsFixer\Config)
+    ->setUnsupportedPhpVersionAllowed(true)
     ->setIndent($config['indent'])
     ->setLineEnding($config['lineEnding'])
     ->setRules($config['rules'])
diff --git a/composer.json b/composer.json
index 25ca245..cdd8f74 100644
--- a/composer.json
+++ b/composer.json
@@ -14,17 +14,17 @@
         }
     ],
     "require": {
-        "php": "^8.2",
+        "php": "^8.3",
         "psr/container": "^2.0.2"
     },
     "require-dev": {
         "chubbyphp/chubbyphp-dev-helper": "dev-master",
-        "chubbyphp/chubbyphp-mock": "^2.0",
-        "infection/infection": "^0.29.13",
-        "php-coveralls/php-coveralls": "^2.7.0",
+        "chubbyphp/chubbyphp-mock": "^2.0.1",
+        "infection/infection": "^0.31.9",
+        "php-coveralls/php-coveralls": "^2.9",
         "phpstan/extension-installer": "^1.4.3",
-        "phpstan/phpstan": "^2.1.6",
-        "phpunit/phpunit": "^11.5.10"
+        "phpstan/phpstan": "^2.1.32",
+        "phpunit/phpunit": "^12.4.5"
     },
     "autoload": {
         "psr-4": { "Chubbyphp\\Container\\": "src/" }
@@ -45,7 +45,7 @@
         }
     },
     "scripts": {
-        "fix:cs": "mkdir -p build && PHP_CS_FIXER_IGNORE_ENV=1 vendor/bin/php-cs-fixer fix --cache-file=build/phpcs.cache",
+        "fix:cs": "mkdir -p build && vendor/bin/php-cs-fixer fix --cache-file=build/phpcs.cache",
         "test": [
             "@test:lint",
             "@test:unit",
@@ -54,7 +54,7 @@
             "@test:static-analysis",
             "@test:cs"
         ],
-        "test:cs": "mkdir -p build && PHP_CS_FIXER_IGNORE_ENV=1 vendor/bin/php-cs-fixer fix --dry-run --stop-on-violation --cache-file=build/phpcs.cache",
+        "test:cs": "mkdir -p build && vendor/bin/php-cs-fixer fix --dry-run --stop-on-violation --cache-file=build/phpcs.cache",
         "test:infection": "vendor/bin/infection --threads=$(nproc) --min-msi=100 --verbose --coverage=build/phpunit",
         "test:integration": "vendor/bin/phpunit --testsuite=Integration --cache-directory=build/phpunit",
         "test:lint": "mkdir -p build && find src tests -name '*.php' -print0 | xargs -0 -n1 -P$(nproc) php -l | tee build/phplint.log",
diff --git a/src/Container.php b/src/Container.php
index 1333823..e58237a 100644
--- a/src/Container.php
+++ b/src/Container.php
@@ -89,10 +89,7 @@ public function prototypeFactory(string $id, callable $factory): ContainerInterf
         return $this;
     }
 
-    /**
-     * @return mixed
-     */
-    public function get(string $id)
+    public function get(string $id): mixed
     {
         if (isset($this->prototypeFactories[$id])) {
             return $this->createFromPrototypeFactory($id);
@@ -106,10 +103,7 @@ public function has(string $id): bool
         return isset($this->factories[$id]) || isset($this->prototypeFactories[$id]);
     }
 
-    /**
-     * @return mixed
-     */
-    private function createFromFactory(string $id)
+    private function createFromFactory(string $id): mixed
     {
         if (!isset($this->factories[$id])) {
             throw NotFoundException::create($id);
@@ -122,10 +116,7 @@ private function createFromFactory(string $id)
         }
     }
 
-    /**
-     * @return mixed
-     */
-    private function createFromPrototypeFactory(string $id)
+    private function createFromPrototypeFactory(string $id): mixed
     {
         try {
             return ($this->prototypeFactories[$id])($this);
diff --git a/src/Exceptions/ExistsException.php b/src/Exceptions/ExistsException.php
index dda849b..c402c04 100644
--- a/src/Exceptions/ExistsException.php
+++ b/src/Exceptions/ExistsException.php
@@ -8,8 +8,9 @@
 
 final class ExistsException extends \LogicException implements ContainerExceptionInterface
 {
-    public const TYPE_FACTORY = 'factory';
-    public const TYPE_PROTOTYPE_FACTORY = 'prototype factory';
+    public const string TYPE_FACTORY = 'factory';
+
+    public const string TYPE_PROTOTYPE_FACTORY = 'prototype factory';
 
     private function __construct(string $message, int $code, ?\Throwable $previous = null)
     {
diff --git a/src/Factory.php b/src/Factory.php
index 400ea61..3d1fe88 100644
--- a/src/Factory.php
+++ b/src/Factory.php
@@ -24,10 +24,7 @@ public function __construct(callable $previousFactory, callable $factory)
         $this->factory = $factory;
     }
 
-    /**
-     * @return mixed
-     */
-    public function __invoke(ContainerInterface $container)
+    public function __invoke(ContainerInterface $container): mixed
     {
         return ($this->factory)($container, $this->previousFactory);
     }
diff --git a/src/MinimalContainer.php b/src/MinimalContainer.php
index 32f0370..eedbf51 100644
--- a/src/MinimalContainer.php
+++ b/src/MinimalContainer.php
@@ -52,10 +52,7 @@ public function factory(string $id, callable $factory): ContainerInterface
         return $this;
     }
 
-    /**
-     * @return mixed
-     */
-    public function get(string $id)
+    public function get(string $id): mixed
     {
         return $this->services[$id] ?? $this->services[$id] = $this->createFromFactory($id);
     }
@@ -65,10 +62,7 @@ public function has(string $id): bool
         return isset($this->factories[$id]);
     }
 
-    /**
-     * @return mixed
-     */
-    private function createFromFactory(string $id)
+    private function createFromFactory(string $id): mixed
     {
         if (!isset($this->factories[$id])) {
             throw NotFoundException::create($id);
diff --git a/src/Parameter.php b/src/Parameter.php
index 78e4c37..43ca44c 100644
--- a/src/Parameter.php
+++ b/src/Parameter.php
@@ -11,10 +11,7 @@ final class Parameter
      */
     public function __construct(private $parameter) {}
 
-    /**
-     * @return mixed
-     */
-    public function __invoke()
+    public function __invoke(): mixed
     {
         return $this->parameter;
     }
diff --git a/tests/Unit/ContainerTest.php b/tests/Unit/ContainerTest.php
index 2463bf1..ec1c34e 100644
--- a/tests/Unit/ContainerTest.php
+++ b/tests/Unit/ContainerTest.php
@@ -8,14 +8,14 @@
 use Chubbyphp\Container\Exceptions\ContainerException;
 use Chubbyphp\Container\Exceptions\ExistsException;
 use Chubbyphp\Container\Exceptions\NotFoundException;
+use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\TestCase;
 use Psr\Container\ContainerInterface;
 
 /**
- * @covers \Chubbyphp\Container\Container
- *
  * @internal
  */
+#[CoversClass(Container::class)]
 final class ContainerTest extends TestCase
 {
     /**
@@ -120,7 +120,7 @@ public function testFactoryReplace(): void
     {
         $container = new Container();
 
-        $container->factory('id', static function (): void {
+        $container->factory('id', static function (): never {
             throw new \Exception('should not be called!');
         });
 
@@ -249,7 +249,7 @@ public function testPrototypeFactoryReplace(): void
     {
         $container = new Container();
 
-        $container->prototypeFactory('id', static function (): void {
+        $container->prototypeFactory('id', static function (): never {
             throw new \Exception('should not be called!');
         });
 
diff --git a/tests/Unit/Exceptions/ContainerExceptionTest.php b/tests/Unit/Exceptions/ContainerExceptionTest.php
index b51dfbc..d0bb756 100644
--- a/tests/Unit/Exceptions/ContainerExceptionTest.php
+++ b/tests/Unit/Exceptions/ContainerExceptionTest.php
@@ -5,13 +5,13 @@
 namespace Chubbyphp\Tests\Container\Unit\Exceptions;
 
 use Chubbyphp\Container\Exceptions\ContainerException;
+use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\TestCase;
 
 /**
- * @covers \Chubbyphp\Container\Exceptions\ContainerException
- *
  * @internal
  */
+#[CoversClass(ContainerException::class)]
 final class ContainerExceptionTest extends TestCase
 {
     public function testConstruct(): void
diff --git a/tests/Unit/Exceptions/ExistsExceptionTest.php b/tests/Unit/Exceptions/ExistsExceptionTest.php
index 2742f76..fe08728 100644
--- a/tests/Unit/Exceptions/ExistsExceptionTest.php
+++ b/tests/Unit/Exceptions/ExistsExceptionTest.php
@@ -5,13 +5,14 @@
 namespace Chubbyphp\Tests\Container\Unit\Exceptions;
 
 use Chubbyphp\Container\Exceptions\ExistsException;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
 
 /**
- * @covers \Chubbyphp\Container\Exceptions\ExistsException
- *
  * @internal
  */
+#[CoversClass(ExistsException::class)]
 final class ExistsExceptionTest extends TestCase
 {
     public function testConstruct(): void
@@ -22,9 +23,7 @@ public function testConstruct(): void
         new ExistsException('test', 0);
     }
 
-    /**
-     * @dataProvider provideCreateCases
-     */
+    #[DataProvider('provideCreateCases')]
     public function testCreate(string $type): void
     {
         $exception = ExistsException::create('id', $type);
diff --git a/tests/Unit/Exceptions/NotFoundExceptionTest.php b/tests/Unit/Exceptions/NotFoundExceptionTest.php
index 2b007e5..a4df076 100644
--- a/tests/Unit/Exceptions/NotFoundExceptionTest.php
+++ b/tests/Unit/Exceptions/NotFoundExceptionTest.php
@@ -5,13 +5,13 @@
 namespace Chubbyphp\Tests\Container\Unit\Exceptions;
 
 use Chubbyphp\Container\Exceptions\NotFoundException;
+use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\TestCase;
 
 /**
- * @covers \Chubbyphp\Container\Exceptions\NotFoundException
- *
  * @internal
  */
+#[CoversClass(NotFoundException::class)]
 final class NotFoundExceptionTest extends TestCase
 {
     public function testConstruct(): void
diff --git a/tests/Unit/FactoryTest.php b/tests/Unit/FactoryTest.php
index c262a5e..ce90a9e 100644
--- a/tests/Unit/FactoryTest.php
+++ b/tests/Unit/FactoryTest.php
@@ -7,14 +7,14 @@
 use Chubbyphp\Container\Factory;
 use Chubbyphp\Mock\MockMethod\WithReturn;
 use Chubbyphp\Mock\MockObjectBuilder;
+use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\TestCase;
 use Psr\Container\ContainerInterface;
 
 /**
- * @covers \Chubbyphp\Container\Factory
- *
  * @internal
  */
+#[CoversClass(Factory::class)]
 final class FactoryTest extends TestCase
 {
     public function testInvoke(): void
diff --git a/tests/Unit/MinimalContainerTest.php b/tests/Unit/MinimalContainerTest.php
index 6734b5e..017691b 100644
--- a/tests/Unit/MinimalContainerTest.php
+++ b/tests/Unit/MinimalContainerTest.php
@@ -7,14 +7,14 @@
 use Chubbyphp\Container\Exceptions\ContainerException;
 use Chubbyphp\Container\Exceptions\NotFoundException;
 use Chubbyphp\Container\MinimalContainer;
+use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\TestCase;
 use Psr\Container\ContainerInterface;
 
 /**
- * @covers \Chubbyphp\Container\MinimalContainer
- *
  * @internal
  */
+#[CoversClass(MinimalContainer::class)]
 final class MinimalContainerTest extends TestCase
 {
     /**
@@ -104,7 +104,7 @@ public function testFactoryReplace(): void
     {
         $container = new MinimalContainer();
 
-        $container->factory('id', static function (): void {
+        $container->factory('id', static function (): never {
             throw new \Exception('should not be called!');
         });
 
diff --git a/tests/Unit/ParameterTest.php b/tests/Unit/ParameterTest.php
index bb57ee8..c33a628 100644
--- a/tests/Unit/ParameterTest.php
+++ b/tests/Unit/ParameterTest.php
@@ -5,18 +5,17 @@
 namespace Chubbyphp\Tests\Container\Unit;
 
 use Chubbyphp\Container\Parameter;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
 
 /**
- * @covers \Chubbyphp\Container\Parameter
- *
  * @internal
  */
+#[CoversClass(Parameter::class)]
 final class ParameterTest extends TestCase
 {
-    /**
-     * @dataProvider provideInvokeCases
-     */
+    #[DataProvider('provideInvokeCases')]
     public function testInvoke(mixed $data): void
     {
         $parameter = new Parameter($data);