diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index 6bdb8844..9e8b6885 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -1,20 +1,22 @@
 <?xml version="1.0" encoding="UTF-8"?>
 <phpunit xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
          xsi:noNamespaceSchemaLocation="https://schema.phpunit.de/12.0/phpunit.xsd"
-         bootstrap="vendor/autoload.php"
+         bootstrap="tests/bootstrap.php"
          cacheDirectory=".phpunit.cache"
          executionOrder="defects"
          requireCoverageMetadata="true"
          beStrictAboutCoverageMetadata="true"
          beStrictAboutOutputDuringTests="true"
          failOnRisky="true"
-         failOnWarning="true">
+         failOnWarning="true"
+         failOnDeprecation="true"
+         displayDetailsOnTestsThatTriggerDeprecations="true">
     <testsuites>
         <testsuite name="default">
             <directory>tests</directory>
         </testsuite>
     </testsuites>
-    <source>
+    <source ignoreSuppressionOfDeprecations="true">
         <include>
             <directory suffix=".php">src</directory>
         </include>
diff --git a/rector.php b/rector.php
index a601b303..68fbff99 100644
--- a/rector.php
+++ b/rector.php
@@ -3,6 +3,7 @@
 declare(strict_types=1);
 
 use Rector\Config\RectorConfig;
+use Rector\DeadCode\Rector\If_\RemoveAlwaysTrueIfConditionRector;
 use Rector\Symfony\Set\SymfonySetList;
 use Rector\ValueObject\PhpVersion;
 
@@ -20,4 +21,8 @@
     ->withSets([
         SymfonySetList::SYMFONY_CONSTRUCTOR_INJECTION,
     ])
+    ->withSkip([
+        // Conditions on the Symfony version: always true with the installed version only
+        RemoveAlwaysTrueIfConditionRector::class => [__DIR__.'/tests/App/TestKernel.php'],
+    ])
 ;
diff --git a/tests/App/TestKernel.php b/tests/App/TestKernel.php
new file mode 100644
index 00000000..bdda2eee
--- /dev/null
+++ b/tests/App/TestKernel.php
@@ -0,0 +1,131 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the CleverAge/ProcessBundle package.
+ *
+ * Copyright (c) Clever-Age
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace CleverAge\ProcessBundle\Tests\App;
+
+use CleverAge\ProcessBundle\CleverAgeProcessBundle;
+use CleverAge\ProcessBundle\Manager\ProcessManager;
+use CleverAge\ProcessBundle\Registry\ProcessConfigurationRegistry;
+use CleverAge\ProcessBundle\Registry\TaskRegistry;
+use CleverAge\ProcessBundle\Registry\TransformerRegistry;
+use Psr\Log\NullLogger;
+use Symfony\Bundle\FrameworkBundle\FrameworkBundle;
+use Symfony\Bundle\FrameworkBundle\Kernel\MicroKernelTrait;
+use Symfony\Component\DependencyInjection\Loader\Configurator\ContainerConfigurator;
+use Symfony\Component\HttpKernel\Kernel;
+use Symfony\Component\Yaml\Yaml;
+
+/**
+ * Application used by the integration tests: the bundle with FrameworkBundle, a process referencing every task of the
+ * bundle by its code and a process to run, in a temporary directory of its own (per PHP process).
+ */
+final class TestKernel extends Kernel
+{
+    use MicroKernelTrait;
+
+    public function registerBundles(): iterable
+    {
+        yield new FrameworkBundle();
+        yield new CleverAgeProcessBundle();
+    }
+
+    public function getProjectDir(): string
+    {
+        return __DIR__;
+    }
+
+    public function getCacheDir(): string
+    {
+        return $this->getRunDir().'/cache/'.$this->environment;
+    }
+
+    public function getLogDir(): string
+    {
+        return $this->getRunDir().'/logs';
+    }
+
+    /**
+     * Codes of the tasks of the bundle (cleverage.task tags of config/services/task.yaml).
+     *
+     * @return list<string>
+     */
+    public static function getTaskCodes(): array
+    {
+        /** @var array{services: array<string, array{tags?: list<array{name?: string, code?: string}|string>}|string|null>} $config */
+        $config = Yaml::parseFile(\dirname(__DIR__, 2).'/config/services/task.yaml', Yaml::PARSE_CUSTOM_TAGS);
+        $codes = [];
+        foreach ($config['services'] as $service) {
+            foreach (\is_array($service) ? $service['tags'] ?? [] : [] as $tag) {
+                if (\is_array($tag) && 'cleverage.task' === ($tag['name'] ?? null) && isset($tag['code'])) {
+                    $codes[] = $tag['code'];
+                }
+            }
+        }
+
+        return $codes;
+    }
+
+    protected function configureContainer(ContainerConfigurator $container): void
+    {
+        $container->extension('framework', [
+            'secret' => 'test',
+            'test' => true,
+            'http_method_override' => false,
+            'handle_all_throwables' => true,
+            'php_errors' => ['log' => true],
+            'validation' => ['email_validation_mode' => 'html5'],
+        ]);
+        if (Kernel::VERSION_ID >= 70300) {
+            // Not setting it is deprecated since Symfony 7.3: its default value changes in 8.0
+            $container->extension('framework', ['property_info' => ['with_constructor_extractor' => true]]);
+        }
+
+        $tasks = [];
+        foreach (self::getTaskCodes() as $code) {
+            $tasks[$code] = ['task' => $code];
+        }
+        $container->extension('clever_age_process', [
+            'configurations' => [
+                'test.every_task' => ['tasks' => $tasks],
+                'test.run' => [
+                    'end_point' => 'format',
+                    'tasks' => [
+                        'constant' => [
+                            'task' => 'constant_output',
+                            'options' => ['output' => 'world'],
+                            'outputs' => ['format'],
+                        ],
+                        'format' => [
+                            'task' => 'transformer',
+                            'options' => ['transformers' => ['sprintf' => ['format' => 'Hello %s']]],
+                        ],
+                    ],
+                ],
+            ],
+        ]);
+
+        $services = $container->services();
+        // The default logger of FrameworkBundle may write the process logs to the output
+        $services->set('logger', NullLogger::class);
+        // Exposed to the tests
+        $services->alias('test.task_registry', TaskRegistry::class)->public();
+        $services->alias('test.transformer_registry', TransformerRegistry::class)->public();
+        $services->alias('test.process_configuration_registry', ProcessConfigurationRegistry::class)->public();
+        $services->alias('test.process_manager', ProcessManager::class)->public();
+    }
+
+    private function getRunDir(): string
+    {
+        return sys_get_temp_dir().'/process_bundle_tests_'.getmypid();
+    }
+}
diff --git a/tests/DependencyInjection/Compiler/RegistryCompilerPassTest.php b/tests/DependencyInjection/Compiler/RegistryCompilerPassTest.php
index de3314dd..97b2a4fd 100644
--- a/tests/DependencyInjection/Compiler/RegistryCompilerPassTest.php
+++ b/tests/DependencyInjection/Compiler/RegistryCompilerPassTest.php
@@ -14,6 +14,7 @@
 namespace CleverAge\ProcessBundle\Tests\DependencyInjection\Compiler;
 
 use CleverAge\ProcessBundle\DependencyInjection\Compiler\RegistryCompilerPass;
+use CleverAge\ProcessBundle\Tests\IgnoreDeprecationsTrait;
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Reference;
@@ -21,6 +22,8 @@
 #[\PHPUnit\Framework\Attributes\CoversClass(RegistryCompilerPass::class)]
 class RegistryCompilerPassTest extends TestCase
 {
+    use IgnoreDeprecationsTrait;
+
     public function testIsDeprecated(): void
     {
         $deprecations = [];
@@ -44,7 +47,7 @@ public function testTaggedServicesAreAddedToTheRegistry(): void
         $container->register('registry', \ArrayObject::class);
         $container->register('service', \stdClass::class)->addTag('tag');
 
-        (new RegistryCompilerPass('registry', 'tag', 'append'))->process($container);
+        self::ignoreDeprecations(static fn () => new RegistryCompilerPass('registry', 'tag', 'append'))->process($container);
 
         self::assertEquals([['append', [new Reference('service')]]], $container->getDefinition('registry')->getMethodCalls());
     }
@@ -54,7 +57,7 @@ public function testMissingRegistryIsIgnored(): void
         $container = new ContainerBuilder();
         $container->register('service', \stdClass::class)->addTag('tag');
 
-        (new RegistryCompilerPass('registry', 'tag', 'append'))->process($container);
+        self::ignoreDeprecations(static fn () => new RegistryCompilerPass('registry', 'tag', 'append'))->process($container);
 
         self::assertFalse($container->has('registry'));
     }
@@ -64,6 +67,6 @@ public function testUndefinedConfigurationThrows(): void
         $this->expectException(\LogicException::class);
         $this->expectExceptionMessage('The registry, tag and method of the RegistryCompilerPass must be defined');
 
-        (new RegistryCompilerPass())->process(new ContainerBuilder());
+        self::ignoreDeprecations(static fn () => new RegistryCompilerPass())->process(new ContainerBuilder());
     }
 }
diff --git a/tests/DependencyInjection/Compiler/TaskLocatorCompilerPassTest.php b/tests/DependencyInjection/Compiler/TaskLocatorCompilerPassTest.php
index 431ab3c3..75825e9c 100644
--- a/tests/DependencyInjection/Compiler/TaskLocatorCompilerPassTest.php
+++ b/tests/DependencyInjection/Compiler/TaskLocatorCompilerPassTest.php
@@ -17,6 +17,7 @@
 use CleverAge\ProcessBundle\DependencyInjection\Compiler\TaskLocatorCompilerPass;
 use CleverAge\ProcessBundle\DependencyInjection\Configuration;
 use CleverAge\ProcessBundle\Task\DummyTask;
+use CleverAge\ProcessBundle\Tests\IgnoreDeprecationsTrait;
 use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\Attributes\UsesClass;
 use PHPUnit\Framework\TestCase;
@@ -32,10 +33,13 @@
 #[UsesClass(Configuration::class)]
 class TaskLocatorCompilerPassTest extends TestCase
 {
+    use IgnoreDeprecationsTrait;
+
     public function testLocatorContainsTheServicesReferencedByTheProcesses(): void
     {
         $container = new ContainerBuilder();
-        (new CleverAgeProcessExtension())->load([[
+        // Deprecated "service" option
+        self::ignoreDeprecations(static fn () => (new CleverAgeProcessExtension())->load([[
             'configurations' => [
                 'test.first' => ['tasks' => [
                     'dummy' => ['service' => '@'.DummyTask::class],
@@ -46,7 +50,7 @@ public function testLocatorContainsTheServicesReferencedByTheProcesses(): void
                     'unknown' => ['service' => '@app.unknown'],
                 ]],
             ],
-        ]], $container);
+        ]], $container));
         // Private services can be fetched from the locator
         $container->setDefinition('app.private_task', (new Definition(DummyTask::class))->setPublic(false));
 
diff --git a/tests/DependencyInjection/ConfigurationTest.php b/tests/DependencyInjection/ConfigurationTest.php
index 8d3ead2b..a5baf3cd 100644
--- a/tests/DependencyInjection/ConfigurationTest.php
+++ b/tests/DependencyInjection/ConfigurationTest.php
@@ -15,6 +15,7 @@
 
 use CleverAge\ProcessBundle\DependencyInjection\CleverAgeProcessExtension;
 use CleverAge\ProcessBundle\DependencyInjection\Configuration;
+use CleverAge\ProcessBundle\Tests\IgnoreDeprecationsTrait;
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\Config\Definition\Exception\InvalidConfigurationException;
 use Symfony\Component\Config\Definition\Processor;
@@ -24,6 +25,8 @@
 #[\PHPUnit\Framework\Attributes\CoversClass(CleverAgeProcessExtension::class)]
 class ConfigurationTest extends TestCase
 {
+    use IgnoreDeprecationsTrait;
+
     public function testLogLevelsDefaults(): void
     {
         $config = $this->process(['configurations' => ['test.process' => ['tasks' => []]]]);
@@ -56,10 +59,11 @@ public function testLogLevelsCanBeConfigured(): void
 
     public function testTaskIsDefinedByAServiceOrACode(): void
     {
-        $config = $this->process(['configurations' => ['test.process' => ['tasks' => [
+        // Deprecated "service" option, see testServiceIsDeprecated()
+        $config = self::ignoreDeprecations(fn (): array => $this->process(['configurations' => ['test.process' => ['tasks' => [
             'by_service' => ['service' => '@app.task'],
             'by_code' => ['task' => 'transformer'],
-        ]]]]);
+        ]]]]));
 
         $tasks = $config['configurations']['test.process']['tasks'];
         self::assertSame(['@app.task', null], [$tasks['by_service']['service'], $tasks['by_service']['task']]);
@@ -107,7 +111,8 @@ public function testTaskMustDefineEitherAServiceOrACode(array $task): void
         $this->expectException(InvalidConfigurationException::class);
         $this->expectExceptionMessage('A task must define either its code ("task: <code>") or, deprecated, its "service", not both');
 
-        $this->process(['configurations' => ['test.process' => ['tasks' => ['invalid' => $task]]]]);
+        // Deprecated "service" option, see testServiceIsDeprecated()
+        self::ignoreDeprecations(fn (): array => $this->process(['configurations' => ['test.process' => ['tasks' => ['invalid' => $task]]]]));
     }
 
     public function testInvalidDefaultLogLevelIsRejected(): void
diff --git a/tests/Functional/KernelTest.php b/tests/Functional/KernelTest.php
new file mode 100644
index 00000000..8e216b3d
--- /dev/null
+++ b/tests/Functional/KernelTest.php
@@ -0,0 +1,95 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the CleverAge/ProcessBundle package.
+ *
+ * Copyright (c) Clever-Age
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace CleverAge\ProcessBundle\Tests\Functional;
+
+use CleverAge\ProcessBundle\Manager\ProcessManager;
+use CleverAge\ProcessBundle\Model\TaskInterface;
+use CleverAge\ProcessBundle\Registry\ProcessConfigurationRegistry;
+use CleverAge\ProcessBundle\Registry\TaskRegistry;
+use CleverAge\ProcessBundle\Registry\TransformerRegistry;
+use CleverAge\ProcessBundle\Tests\App\TestKernel;
+use CleverAge\ProcessBundle\Transformer\TransformerInterface;
+use PHPUnit\Framework\Attributes\CoversNothing;
+use Symfony\Bundle\FrameworkBundle\Test\KernelTestCase;
+
+/**
+ * The bundle in an application (see TestKernel): the container compiles, the tasks and transformers are resolved with
+ * their dependencies, a process runs.
+ */
+#[CoversNothing]
+class KernelTest extends KernelTestCase
+{
+    private mixed $exceptionHandler;
+
+    protected function setUp(): void
+    {
+        $this->exceptionHandler = $this->getExceptionHandler();
+    }
+
+    protected function tearDown(): void
+    {
+        parent::tearDown();
+        // The ErrorHandler registered when the kernel boots is not removed by the first Symfony 6.4 versions
+        if ($this->getExceptionHandler() !== $this->exceptionHandler) {
+            restore_exception_handler();
+        }
+    }
+
+    public function testEveryTaskIsResolvedByItsCode(): void
+    {
+        $processConfigurationRegistry = self::getContainer()->get('test.process_configuration_registry');
+        self::assertInstanceOf(ProcessConfigurationRegistry::class, $processConfigurationRegistry);
+        $taskRegistry = self::getContainer()->get('test.task_registry');
+        self::assertInstanceOf(TaskRegistry::class, $taskRegistry);
+
+        $processConfiguration = $processConfigurationRegistry->getProcessConfiguration('test.every_task');
+        $codes = TestKernel::getTaskCodes();
+        self::assertNotEmpty($codes);
+        foreach ($codes as $code) {
+            self::assertInstanceOf(TaskInterface::class, $taskRegistry->getTask($processConfiguration->getTaskConfiguration($code)), $code);
+        }
+    }
+
+    public function testEveryTransformerIsResolved(): void
+    {
+        $transformerRegistry = self::getContainer()->get('test.transformer_registry');
+        self::assertInstanceOf(TransformerRegistry::class, $transformerRegistry);
+
+        $transformers = $transformerRegistry->getTransformers();
+        self::assertNotEmpty($transformers);
+        self::assertContainsOnlyInstancesOf(TransformerInterface::class, $transformers);
+        self::assertInstanceOf(TransformerInterface::class, $transformerRegistry->getTransformer('sprintf'));
+    }
+
+    public function testProcessIsExecuted(): void
+    {
+        $processManager = self::getContainer()->get('test.process_manager');
+        self::assertInstanceOf(ProcessManager::class, $processManager);
+
+        self::assertSame('Hello world', $processManager->execute('test.run'));
+    }
+
+    private function getExceptionHandler(): mixed
+    {
+        $handler = set_exception_handler(null);
+        restore_exception_handler();
+
+        return $handler;
+    }
+
+    protected static function getKernelClass(): string
+    {
+        return TestKernel::class;
+    }
+}
diff --git a/tests/IgnoreDeprecationsTrait.php b/tests/IgnoreDeprecationsTrait.php
new file mode 100644
index 00000000..b17c519b
--- /dev/null
+++ b/tests/IgnoreDeprecationsTrait.php
@@ -0,0 +1,38 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the CleverAge/ProcessBundle package.
+ *
+ * Copyright (c) Clever-Age
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace CleverAge\ProcessBundle\Tests;
+
+/**
+ * For the tests using a deprecated feature whose deprecation is checked by another test: the tests fail on
+ * deprecations (failOnDeprecation).
+ */
+trait IgnoreDeprecationsTrait
+{
+    /**
+     * @template T
+     *
+     * @param callable(): T $callback
+     *
+     * @return T
+     */
+    private static function ignoreDeprecations(callable $callback): mixed
+    {
+        set_error_handler(static fn (): bool => true, \E_USER_DEPRECATED);
+        try {
+            return $callback();
+        } finally {
+            restore_error_handler();
+        }
+    }
+}
diff --git a/tests/Transformer/CallbackTransformerTest.php b/tests/Transformer/CallbackTransformerTest.php
index 3f88d162..6b17d323 100644
--- a/tests/Transformer/CallbackTransformerTest.php
+++ b/tests/Transformer/CallbackTransformerTest.php
@@ -13,6 +13,7 @@
 
 namespace CleverAge\ProcessBundle\Tests\Transformer;
 
+use CleverAge\ProcessBundle\Tests\IgnoreDeprecationsTrait;
 use CleverAge\ProcessBundle\Transformer\CallbackTransformer;
 use PHPUnit\Framework\Attributes\DataProvider;
 use PHPUnit\Framework\TestCase;
@@ -23,6 +24,8 @@
 #[\PHPUnit\Framework\Attributes\CoversClass(CallbackTransformer::class)]
 class CallbackTransformerTest extends TestCase
 {
+    use IgnoreDeprecationsTrait;
+
     public static function doCallback(mixed ...$args): string
     {
         return implode('-', $args);
@@ -82,10 +85,10 @@ public function testTransform(array $options, mixed $value, mixed $expected): vo
     public function testAdditionalParametersAreUsedAsRightParameters(): void
     {
         $transformer = new CallbackTransformer();
-        $options = $this->resolveOptions($transformer, [
+        $options = self::ignoreDeprecations(fn (): array => $this->resolveOptions($transformer, [
             'callback' => [self::class, 'doCallback'],
             'additional_parameters' => [7, 8],
-        ]);
+        ]));
 
         self::assertSame('6-7-8', $transformer->transform('6', $options));
     }
@@ -121,11 +124,11 @@ public function testAdditionalParametersAreDeprecated(): void
     public function testAdditionalParametersAreIgnoredWhenRightParametersAreSet(): void
     {
         $transformer = new CallbackTransformer();
-        $options = $this->resolveOptions($transformer, [
+        $options = self::ignoreDeprecations(fn (): array => $this->resolveOptions($transformer, [
             'callback' => [self::class, 'doCallback'],
             'right_parameters' => [4],
             'additional_parameters' => [7, 8],
-        ]);
+        ]));
 
         self::assertSame('6-4', $transformer->transform('6', $options));
     }
diff --git a/tests/Transformer/Serialization/DenormalizeTransformerTest.php b/tests/Transformer/Serialization/DenormalizeTransformerTest.php
index e05faa53..baab1728 100644
--- a/tests/Transformer/Serialization/DenormalizeTransformerTest.php
+++ b/tests/Transformer/Serialization/DenormalizeTransformerTest.php
@@ -49,7 +49,7 @@ public function testCollectionClassIsSupported(): void
         $transformer = $this->createTransformer();
         $options = $this->resolveOptions($transformer, ['class' => \DateTimeImmutable::class.'[]']);
 
-        $result = $transformer->transform(['a' => '2024-01-02', 'b' => '2024-02-03'], $options);
+        $result = $transformer->transform(['a' => '2024-01-02T00:00:00+00:00', 'b' => '2024-02-03T00:00:00+00:00'], $options);
 
         self::assertIsArray($result);
         self::assertSame(['a', 'b'], array_keys($result));
diff --git a/tests/bootstrap.php b/tests/bootstrap.php
new file mode 100644
index 00000000..ede03ad4
--- /dev/null
+++ b/tests/bootstrap.php
@@ -0,0 +1,19 @@
+<?php
+
+declare(strict_types=1);
+
+/*
+ * This file is part of the CleverAge/ProcessBundle package.
+ *
+ * Copyright (c) Clever-Age
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+use Symfony\Component\ErrorHandler\DebugClassLoader;
+
+require __DIR__.'/../vendor/autoload.php';
+
+// Deprecations of the class loading: extending a class marked @final or @internal, missing return types...
+DebugClassLoader::enable();