diff --git a/.composer-require-checker.json b/.composer-require-checker.json
index 2c63c08..7ec31a8 100644
--- a/.composer-require-checker.json
+++ b/.composer-require-checker.json
@@ -1,2 +1,17 @@
 {
+  "symbol-whitelist" : [
+    "null", "true", "false",
+    "self", "parent",
+    "array", "string", "int", "float", "bool", "iterable", "callable", "void", "object",
+    "Contao\\ManagerPlugin\\Bundle\\BundlePluginInterface",
+    "Contao\\ManagerPlugin\\Bundle\\Config\\BundleConfig",
+    "Contao\\ManagerPlugin\\Bundle\\Parser\\ParserInterface",
+    "Contao\\ManagerPlugin\\Config\\ConfigPluginInterface",
+    "Contao\\ManagerPlugin\\Routing\\RoutingPluginInterface",
+    "CyberSpectrum\\I18N\\MetaModels\\MetaModelDictionaryDefinitionBuilder",
+    "CyberSpectrum\\I18N\\MetaModels\\MetaModelDictionaryProvider",
+    "MadeYourDay\\RockSolidCustomElements\\RockSolidCustomElementsBundle",
+    "MetaModels\\CoreBundle\\MetaModelsCoreBundle",
+    "Terminal42\\ChangeLanguage\\Terminal42ChangeLanguageBundle"
+  ]
 }
diff --git a/composer.json b/composer.json
index dee5df1..7bac0d4 100644
--- a/composer.json
+++ b/composer.json
@@ -22,13 +22,17 @@
   },
   "require": {
     "php": "^7.1.3",
+    "ext-json": "*",
     "contao/core-bundle": "^4.4.0",
     "cyberspectrum/i18n": "dev-fix/phpcq-2 as 1.0.0@dev",
     "cyberspectrum/i18n-bundle": "dev-fix/phpcq-2 as 1.0.0@dev",
     "cyberspectrum/i18n-contao": "dev-fix/phpcq-2 as 1.0.0@dev",
     "cyberspectrum/i18n-xliff": "dev-fix/phpcq-2 as 1.0.0@dev",
+    "psr/log": "^1.1.4 || ^2.0 || ^3.0",
     "symfony/config": "^3.4 || ^4.1 || ^5.0",
+    "symfony/console": "^3.4 || ^4.1 || ^5.0",
     "symfony/dependency-injection": "^4.4 || ^5.4 || ^6.0",
+    "symfony/error-handler": "^4.4 || ^5.4 || ^6.0",
     "symfony/form": "^4.4 || ^5.4 || ^6.0",
     "symfony/framework-bundle": "^4.4 || ^5.4 || ^6.0",
     "symfony/http-foundation": "^4.4 || ^5.4 || ^6.0",
@@ -42,7 +46,6 @@
     "contao-community-alliance/dc-general": "^2.1",
     "contao/manager-plugin": "^2.6.0",
     "cyberspectrum/i18n-metamodels": "dev-fix/phpcq-2 as 1.0.0@dev",
-    "metamodels/core": "^2.1",
     "phpcq/runner-bootstrap": "^1.0@dev"
   },
   "suggest": {
diff --git a/src/Command/DebugMapCommand.php b/src/Command/DebugMapCommand.php
index 8ef3f86..e2eedf6 100644
--- a/src/Command/DebugMapCommand.php
+++ b/src/Command/DebugMapCommand.php
@@ -1,23 +1,6 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2019 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2019 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\Command;
 
@@ -33,12 +16,8 @@
  */
 class DebugMapCommand extends Command
 {
-    /**
-     * The map builder.
-     *
-     * @var MapBuilderInterface
-     */
-    private $mapBuilder;
+    /** The map builder. */
+    private MapBuilderInterface $mapBuilder;
 
     /**
      * Create a new instance.
@@ -51,28 +30,25 @@ public function __construct(MapBuilderInterface $mapBuilder)
         $this->mapBuilder = $mapBuilder;
     }
 
-    /**
-     * {@inheritDoc}
-     */
     protected function configure(): void
     {
         parent::configure();
 
         $this->setName('debug:i18n-map');
         $this->setDescription('Dump the mapping');
-        $this->addArgument('table', InputArgument::OPTIONAL, 'The table name');
-        $this->addArgument('source-language', InputArgument::OPTIONAL, 'The source language');
-        $this->addArgument('target-language', InputArgument::OPTIONAL, 'The target language');
+        $this->addArgument('table', InputArgument::REQUIRED, 'The table name');
+        $this->addArgument('source-language', InputArgument::REQUIRED, 'The source language');
+        $this->addArgument('target-language', InputArgument::REQUIRED, 'The target language');
     }
 
-    /**
-     * {@inheritDoc}
-     */
-    protected function execute(InputInterface $input, OutputInterface $output)
+    protected function execute(InputInterface $input, OutputInterface $output): int
     {
-        $tableName      = $input->getArgument('table');
+        $tableName = $input->getArgument('table');
+        assert(is_string($tableName));
         $sourceLanguage = $input->getArgument('source-language');
+        assert(is_string($sourceLanguage));
         $targetLanguage = $input->getArgument('target-language');
+        assert(is_string($targetLanguage));
 
         $tableMap = $this->mapBuilder->getMappingFor($tableName, $sourceLanguage, $targetLanguage);
         $keys     = $tableMap->sourceIds();
@@ -83,5 +59,7 @@ protected function execute(InputInterface $input, OutputInterface $output)
         }
 
         $table->render();
+
+        return 0;
     }
 }
diff --git a/src/ContaoManager/Plugin.php b/src/ContaoManager/Plugin.php
index c63eeef..1cdb404 100644
--- a/src/ContaoManager/Plugin.php
+++ b/src/ContaoManager/Plugin.php
@@ -1,23 +1,6 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\ContaoManager;
 
@@ -27,13 +10,14 @@
 use Contao\ManagerPlugin\Bundle\Parser\ParserInterface;
 use Contao\ManagerPlugin\Config\ConfigPluginInterface;
 use Contao\ManagerPlugin\Routing\RoutingPluginInterface;
-use CyberSpectrum\I18N\ContaoBundle\CyberSpectrumI18NContaoBundle;
 use CyberSpectrum\I18NBundle\CyberSpectrumI18NBundle;
+use CyberSpectrum\I18N\ContaoBundle\CyberSpectrumI18NContaoBundle;
 use MetaModels\CoreBundle\MetaModelsCoreBundle;
 use Symfony\Bundle\FrameworkBundle\FrameworkBundle;
 use Symfony\Component\Config\Loader\LoaderInterface;
 use Symfony\Component\Config\Loader\LoaderResolverInterface;
 use Symfony\Component\HttpKernel\KernelInterface;
+use Symfony\Component\Routing\RouteCollection;
 
 /**
  * Plugin for the Contao Manager.
@@ -43,7 +27,7 @@ class Plugin implements BundlePluginInterface, ConfigPluginInterface, RoutingPlu
     /**
      * {@inheritdoc}
      */
-    public function getBundles(ParserInterface $parser)
+    public function getBundles(ParserInterface $parser): array
     {
         return [
             BundleConfig::create(CyberSpectrumI18NContaoBundle::class)
@@ -62,18 +46,26 @@ public function getBundles(ParserInterface $parser)
     /**
      * {@inheritDoc}
      */
-    public function registerContainerConfiguration(LoaderInterface $loader, array $managerConfig)
+    public function registerContainerConfiguration(LoaderInterface $loader, array $managerConfig): void
     {
         $loader->load('@CyberSpectrumI18NContaoBundle/Resources/contao-manager/framework.yml');
     }
 
     /**
      * {@inheritDoc}
+     *
+     * @psalm-suppress MixedInferredReturnType
+     * @psalm-suppress MixedReturnStatement
      */
-    public function getRouteCollection(LoaderResolverInterface $resolver, KernelInterface $kernel)
+    public function getRouteCollection(LoaderResolverInterface $resolver, KernelInterface $kernel): ?RouteCollection
     {
-        return $resolver
-            ->resolve(__DIR__.'/../Resources/config/contao/routing.yml')
-            ->load(__DIR__.'/../Resources/config/contao/routing.yml');
+        $loader = $resolver->resolve(__DIR__ . '/../Resources/config/contao/routing.yml');
+
+        if (!$loader instanceof LoaderInterface) {
+            throw new \RuntimeException('Failed to load routes');
+        }
+
+        return $loader
+            ->load(__DIR__ . '/../Resources/config/contao/routing.yml');
     }
 }
diff --git a/src/Controller/ContaoInspectProblemsController.php b/src/Controller/ContaoInspectProblemsController.php
index 17b33c0..9dce9d3 100644
--- a/src/Controller/ContaoInspectProblemsController.php
+++ b/src/Controller/ContaoInspectProblemsController.php
@@ -1,68 +1,39 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\Controller;
 
 use CyberSpectrum\I18N\Contao\Mapping\MapBuilderInterface;
 use CyberSpectrum\I18N\Contao\Mapping\Terminal42ChangeLanguage\ArticleMap;
 use CyberSpectrum\I18N\ContaoBundle\FormType\InspectMappingFormType;
+use Psr\Log\LoggerAwareInterface;
 use Symfony\Bundle\FrameworkBundle\Controller\AbstractController;
-use Symfony\Component\Debug\BufferingLogger;
+use Symfony\Component\ErrorHandler\BufferingLogger;
 use Symfony\Component\HttpFoundation\Request;
 use Symfony\Component\HttpFoundation\Response;
 use Symfony\Component\Security\Csrf\CsrfTokenManager;
 use Symfony\Component\Templating\EngineInterface;
 
+use function in_array;
+use function strtr;
+
 /**
  * This allows to inspect dictionary problems in the Contao backend.
  */
 class ContaoInspectProblemsController extends AbstractController
 {
-    /**
-     * The twig engine.
-     *
-     * @var EngineInterface
-     */
-    private $templating;
+    /** The twig engine. */
+    private EngineInterface $templating;
 
-    /**
-     * The Contao map builder.
-     *
-     * @var MapBuilderInterface
-     */
-    private $mapBuilder;
+    /** The Contao map builder. */
+    private MapBuilderInterface $mapBuilder;
 
-    /**
-     * The CSRF token manager.
-     *
-     * @var CsrfTokenManager
-     */
-    private $csrfTokenManager;
+    /** The CSRF token manager. */
+    private CsrfTokenManager $csrfTokenManager;
 
-    /**
-     * The CSRF token name.
-     *
-     * @var string
-     */
-    private $csrfTokenName;
+    /** The CSRF token name. */
+    private string $csrfTokenName;
 
     /**
      * Create a new instance.
@@ -93,7 +64,7 @@ public function __construct(
      */
     public function __invoke(Request $request): Response
     {
-        switch ($request->get('act')) {
+        switch ($request->query->get('act')) {
             case 'inspect-map':
                 return $this->inspectMap($request);
             default:
@@ -106,25 +77,29 @@ public function __invoke(Request $request): Response
      * Inspect Terminal42 mappings.
      *
      * @param Request $request The request.
-     *
-     * @return Response
      */
     private function inspectMap(Request $request): Response
     {
-        if (empty($map = $request->get('map'))) {
+        if (empty($map = $request->query->get('map'))) {
             $map = 'tl_page';
         }
+        assert(is_string($map));
 
         $form = $this->createForm(InspectMappingFormType::class);
         $form->handleRequest($request);
 
-        $logger = new BufferingLogger();
+        /** @var array{source: string, target: string} $data */
         $data   = $form->getData();
+        $logger = new BufferingLogger();
         $errors = [];
         if ($form->isSubmitted() && $form->isValid()) {
-            $this->mapBuilder->setLogger($logger);
+            if ($this->mapBuilder instanceof LoggerAwareInterface) {
+                $this->mapBuilder->setLogger($logger);
+            }
             $this->mapBuilder->getMappingFor($map, $data['source'], $data['target']);
-            foreach ($logger->cleanLogs() as $message) {
+            /** @var list<array{0: string, 1: string, 2: array<string, string>}> $logs */
+            $logs = $logger->cleanLogs();
+            foreach ($logs as $message) {
                 if ([] !== ($converted = $this->convertMessage($message))) {
                     $errors[] = $converted;
                 }
@@ -143,7 +118,7 @@ private function inspectMap(Request $request): Response
     /**
      * Convert an error message to the correct error array.
      *
-     * @param array $message The error message to convert.
+     * @param array{0: string, 1: string, 2: array<string, string>} $message The error message to convert.
      *
      * @return array
      *
@@ -153,7 +128,7 @@ private function inspectMap(Request $request): Response
     private function convertMessage(array $message): array
     {
         [$level, $text, $context] = $message;
-        if (!\in_array($level, ['warning', 'error'])) {
+        if (!in_array($level, ['warning', 'error'])) {
             return [];
         }
 
@@ -281,10 +256,8 @@ private function link(array $params): array
     /**
      * Transform the message by replacing the context parameters.
      *
-     * @param string $message The message template.
-     * @param array  $context The context parameters.
-     *
-     * @return string
+     * @param string                $message The message template.
+     * @param array<string, string> $context The context parameters.
      */
     private function transformMessage(string $message, array $context): string
     {
diff --git a/src/CyberSpectrumI18NContaoBundle.php b/src/CyberSpectrumI18NContaoBundle.php
index 16e91cd..1423f4c 100644
--- a/src/CyberSpectrumI18NContaoBundle.php
+++ b/src/CyberSpectrumI18NContaoBundle.php
@@ -1,23 +1,6 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle;
 
@@ -36,10 +19,7 @@
  */
 class CyberSpectrumI18NContaoBundle extends Bundle
 {
-    /**
-     * {@inheritDoc}
-     */
-    public function build(ContainerBuilder $container)
+    public function build(ContainerBuilder $container): void
     {
         parent::build($container);
 
diff --git a/src/DependencyInjection/CompilerPass/CollectContaoExtractorsPass.php b/src/DependencyInjection/CompilerPass/CollectContaoExtractorsPass.php
index 2b71247..8f70339 100644
--- a/src/DependencyInjection/CompilerPass/CollectContaoExtractorsPass.php
+++ b/src/DependencyInjection/CompilerPass/CollectContaoExtractorsPass.php
@@ -1,31 +1,17 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\DependencyInjection\CompilerPass;
 
 use CyberSpectrum\I18N\Contao\ExtractorFactory;
+use RuntimeException;
 use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Reference;
 
+use function array_key_exists;
+
 /**
  * This pass adds tagged services to the various factories.
  */
@@ -41,11 +27,9 @@ class CollectContaoExtractorsPass implements CompilerPassInterface
      *
      * @param ContainerBuilder $container The container builder.
      *
-     * @return void
-     *
-     * @throws \RuntimeException When a tag has no table name.
+     * @throws RuntimeException When a tag has no table name.
      */
-    public function process(ContainerBuilder $container)
+    public function process(ContainerBuilder $container): void
     {
         if (!$container->has(ExtractorFactory::class)) {
             return;
@@ -54,13 +38,19 @@ public function process(ContainerBuilder $container)
             return;
         }
 
+        /** @var array<string, list<string>> $extractorLists */
         $extractorLists     = [];
         $extractorContainer = $container->getDefinition('cyberspectrum_i18n.contao.extractor_container');
-        $extractorList      = $extractorContainer->getArgument(0);
+        /** @var array<string, Reference> $extractorList */
+        $extractorList = $extractorContainer->getArgument(0);
+        /**
+         * @var string $serviceId
+         * @var list<array{table?: string}> $tags
+         */
         foreach ($services as $serviceId => $tags) {
             foreach ($tags as $tag) {
                 if (!array_key_exists('table', $tag)) {
-                    throw new \RuntimeException('Tagged service "'. $serviceId .'" has no table name.');
+                    throw new RuntimeException('Tagged service "' . $serviceId . '" has no table name.');
                 }
 
                 $tableName = $tag['table'];
diff --git a/src/DependencyInjection/CompilerPass/CollectExtractorConditionsPass.php b/src/DependencyInjection/CompilerPass/CollectExtractorConditionsPass.php
index f4cc446..4fd5f91 100644
--- a/src/DependencyInjection/CompilerPass/CollectExtractorConditionsPass.php
+++ b/src/DependencyInjection/CompilerPass/CollectExtractorConditionsPass.php
@@ -1,23 +1,6 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\DependencyInjection\CompilerPass;
 
@@ -28,26 +11,29 @@
 use CyberSpectrum\I18N\Contao\Extractor\ConditionalStringExtractor;
 use CyberSpectrum\I18N\Contao\Extractor\MultiStringExtractorInterface;
 use CyberSpectrum\I18N\Contao\Extractor\StringExtractorInterface;
+use RuntimeException;
 use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Definition;
 use Symfony\Component\DependencyInjection\Reference;
 
+use function array_merge;
+use function array_slice;
+use function assert;
+use function in_array;
+use function is_array;
+use function json_encode;
+use function sprintf;
+
 /**
  * This pass adds tagged services to the various factories.
  */
 class CollectExtractorConditionsPass implements CompilerPassInterface
 {
-    /**
-     * The tag name to use for attribute factories.
-     */
+    /** The tag name to use for attribute factories. */
     public const TAG_CONTAO_EXTRACTOR_CONDITION = 'cyberspectrum_i18n.contao_condition';
 
-    /**
-     * Id of the expression language to use.
-     *
-     * @var string
-     */
+    /** Id of the expression language to use. */
     private const EXPRESSION_LANGUAGE = 'cyberspectrum_i18n.expression_language';
 
     /**
@@ -55,9 +41,7 @@ class CollectExtractorConditionsPass implements CompilerPassInterface
      *
      * @param ContainerBuilder $container The container builder.
      *
-     * @return void
-     *
-     * @throws \RuntimeException When a tag has no table name.
+     * @throws RuntimeException When a tag has no table name.
      */
     public function process(ContainerBuilder $container): void
     {
@@ -65,6 +49,10 @@ public function process(ContainerBuilder $container): void
             return;
         }
 
+        /**
+         * @var string $serviceId
+         * @var list<array{type?: string}> $tags
+         */
         foreach ($services as $serviceId => $tags) {
             foreach ($tags as $tag) {
                 $this->handleTag($serviceId, $tag, $container);
@@ -79,9 +67,7 @@ public function process(ContainerBuilder $container): void
      * @param array            $tag       The tag content.
      * @param ContainerBuilder $container The container builder.
      *
-     * @return void
-     *
-     * @throws \RuntimeException On error.
+     * @throws RuntimeException On error.
      */
     private function handleTag(string $serviceId, array $tag, ContainerBuilder $container): void
     {
@@ -91,11 +77,13 @@ private function handleTag(string $serviceId, array $tag, ContainerBuilder $cont
             return;
         }
 
+        /** @var list<Reference> $conditions */
         $conditions = [];
+        /** @var array{0: string, 1: list<mixed> } $call */
         foreach ($definition->getMethodCalls() as $call) {
             if ('setCondition' === $call[0]) {
                 if (!$call[1][0] instanceof Reference) {
-                    throw new \RuntimeException('Expected a reference as argument');
+                    throw new RuntimeException('Expected a reference as argument');
                 }
                 $conditions[] = $call[1][0];
             }
@@ -107,16 +95,16 @@ private function handleTag(string $serviceId, array $tag, ContainerBuilder $cont
 
         // Scan if any of the conditions is a WhitelistCondition - if so, add all other to that one.
         foreach ($conditions as $index => $condition) {
-            /** @var Reference $condition */
-            $referenced = $container->getDefinition($condition);
+            $referenced = $container->getDefinition($condition->__toString());
             if ($referenced->getClass() === WhitelistCondition::class) {
                 $arguments = $referenced->getArgument(0);
+                assert(is_array($arguments));
 
                 $referenced->setArgument(
                     0,
                     array_merge(
-                        \array_slice($arguments, 0, $index),
-                        \array_slice($arguments, ($index + 1)),
+                        array_slice($arguments, 0, $index),
+                        array_slice($arguments, ($index + 1)),
                         [$newCondition]
                     )
                 );
@@ -146,12 +134,15 @@ private function handleTag(string $serviceId, array $tag, ContainerBuilder $cont
      *
      * @return Definition
      *
-     * @throws \RuntimeException On error.
+     * @throws RuntimeException On error.
      */
     private function ensureConditionalService(string $serviceId, ContainerBuilder $container): Definition
     {
         $definition = $container->getDefinition($serviceId);
-        if ($this->classImplements($class = $definition->getClass(), ConditionalExtractorInterface::class)) {
+        if (
+            (null === ($class = $definition->getClass()))
+            || $this->classImplements($class, ConditionalExtractorInterface::class)
+        ) {
             return $definition;
         }
 
@@ -181,12 +172,14 @@ private function ensureConditionalService(string $serviceId, ContainerBuilder $c
             default:
         }
 
-        throw new \RuntimeException(sprintf(
-            'Class %1$s does not implement %2$s - can not apply conditions (service: %3$s).',
-            $definition->getClass(),
-            ConditionalExtractorInterface::class,
-            $serviceId
-        ));
+        throw new RuntimeException(
+            sprintf(
+                'Class %1$s does not implement %2$s - can not apply conditions (service: %3$s).',
+                $definition->getClass() ?? '?',
+                ConditionalExtractorInterface::class,
+                $serviceId
+            )
+        );
     }
 
     /**
@@ -194,12 +187,10 @@ private function ensureConditionalService(string $serviceId, ContainerBuilder $c
      *
      * @param string $class     The class to test.
      * @param string $interface The interface to test.
-     *
-     * @return bool
      */
     private function classImplements(string $class, string $interface): bool
     {
-        return \in_array($interface, class_implements($class), true);
+        return in_array($interface, class_implements($class), true);
     }
 
     /**
@@ -211,12 +202,12 @@ private function classImplements(string $class, string $interface): bool
      *
      * @return Reference
      *
-     * @throws \RuntimeException When the condition type is unknown.
+     * @throws RuntimeException When the condition type is unknown.
      */
     private function createCondition(string $serviceId, array $tag, ContainerBuilder $container): Reference
     {
         if (!isset($tag['type'])) {
-            throw new \RuntimeException(sprintf(
+            throw new RuntimeException(sprintf(
                 'No type given for condition of service: %1$s.',
                 $serviceId
             ));
@@ -225,7 +216,7 @@ private function createCondition(string $serviceId, array $tag, ContainerBuilder
         switch ($tag['type']) {
             case 'expression':
                 if (!isset($tag['expression'])) {
-                    throw new \RuntimeException('Expression missing in tag for: ' . $serviceId);
+                    throw new RuntimeException('Expression missing in tag for: ' . $serviceId);
                 }
                 $container->setDefinition(
                     $conditionId = 'cyberspectrum_i18n.contao.extractor.condition.' .
@@ -240,6 +231,6 @@ private function createCondition(string $serviceId, array $tag, ContainerBuilder
             default:
         }
 
-        throw new \RuntimeException('Unknown condition tag: ' . json_encode($tag));
+        throw new RuntimeException('Unknown condition tag: ' . json_encode($tag));
     }
 }
diff --git a/src/DependencyInjection/CompilerPass/CollectMetaModelAttributeHandlerPass.php b/src/DependencyInjection/CompilerPass/CollectMetaModelAttributeHandlerPass.php
index 88bf518..6571c43 100644
--- a/src/DependencyInjection/CompilerPass/CollectMetaModelAttributeHandlerPass.php
+++ b/src/DependencyInjection/CompilerPass/CollectMetaModelAttributeHandlerPass.php
@@ -1,23 +1,6 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\DependencyInjection\CompilerPass;
 
@@ -35,10 +18,7 @@ class CollectMetaModelAttributeHandlerPass implements CompilerPassInterface
      */
     public const TAG_ATTRIBUTE_HANDLER_FACTORY = 'cyberspectrum_i18n.metamodels.attribute_handler';
 
-    /**
-     * {@inheritDoc}
-     */
-    public function process(ContainerBuilder $container)
+    public function process(ContainerBuilder $container): void
     {
         if (!$container->hasDefinition('cyberspectrum_i18n.metamodels.attribute_handler_factories')) {
             return;
@@ -46,7 +26,12 @@ public function process(ContainerBuilder $container)
 
         $factoryList = $container->getDefinition('cyberspectrum_i18n.metamodels.attribute_handler_factories');
         $factories   = $factoryList->getArgument(0);
+        assert(\is_array($factories));
 
+        /**
+         * @var string $serviceId
+         * @var list<array{type?: string}> $tags
+         */
         foreach ($container->findTaggedServiceIds(self::TAG_ATTRIBUTE_HANDLER_FACTORY) as $serviceId => $tags) {
             foreach ($tags as $tag) {
                 if ($type = ($tag['type'] ?? null)) {
diff --git a/src/DependencyInjection/CompilerPass/RegisterDictionaryTypesPass.php b/src/DependencyInjection/CompilerPass/RegisterDictionaryTypesPass.php
index d676d1a..eca12ac 100644
--- a/src/DependencyInjection/CompilerPass/RegisterDictionaryTypesPass.php
+++ b/src/DependencyInjection/CompilerPass/RegisterDictionaryTypesPass.php
@@ -1,33 +1,21 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\DependencyInjection\CompilerPass;
 
 use CyberSpectrum\I18N\Contao\ContaoDictionaryDefinitionBuilder;
 use CyberSpectrum\I18N\MetaModels\MetaModelDictionaryDefinitionBuilder;
 use CyberSpectrum\I18N\MetaModels\MetaModelDictionaryProvider;
+use RuntimeException;
 use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Reference;
 
+use function array_merge;
+use function assert;
+use function is_array;
+
 /**
  * This pass adds dictionary builders.
  */
@@ -40,7 +28,7 @@ class RegisterDictionaryTypesPass implements CompilerPassInterface
      *
      * @return void
      *
-     * @throws \RuntimeException When a tag has no provider name or multiple services have been registered.
+     * @throws RuntimeException When a tag has no provider name or multiple services have been registered.
      */
     public function process(ContainerBuilder $container): void
     {
@@ -51,6 +39,8 @@ public function process(ContainerBuilder $container): void
         }
 
         $definition = $container->getDefinition('cyberspectrum_i18n.dictionary_definition_builders');
-        $definition->setArgument(0, array_merge($definition->getArgument(0), $builders));
+        $prevBuilders = $definition->getArgument(0);
+        assert(is_array($prevBuilders));
+        $definition->setArgument(0, array_merge($prevBuilders, $builders));
     }
 }
diff --git a/src/DependencyInjection/CompilerPass/SetDefaultsPass.php b/src/DependencyInjection/CompilerPass/SetDefaultsPass.php
index fc38758..1f55cde 100644
--- a/src/DependencyInjection/CompilerPass/SetDefaultsPass.php
+++ b/src/DependencyInjection/CompilerPass/SetDefaultsPass.php
@@ -1,28 +1,12 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\DependencyInjection\CompilerPass;
 
 use CyberSpectrum\I18N\Contao\ContaoDictionaryProvider;
 use CyberSpectrum\I18N\Contao\Mapping\Terminal42ChangeLanguage\MapBuilder as Terminal42MapBuilder;
+use RuntimeException;
 use Symfony\Component\DependencyInjection\Compiler\CompilerPassInterface;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 
@@ -31,10 +15,7 @@
  */
 class SetDefaultsPass implements CompilerPassInterface
 {
-    /**
-     * {@inheritDoc}
-     */
-    public function process(ContainerBuilder $container)
+    public function process(ContainerBuilder $container): void
     {
         if ($container->has(ContaoDictionaryProvider::class)) {
             $this->setDefaultMapBuilder($container);
@@ -46,9 +27,7 @@ public function process(ContainerBuilder $container)
      *
      * @param ContainerBuilder $container The container builder.
      *
-     * @return void
-     *
-     * @throws \RuntimeException When no default map builder has been defined.
+     * @throws RuntimeException When no default map builder has been defined.
      */
     private function setDefaultMapBuilder(ContainerBuilder $container): void
     {
@@ -60,7 +39,7 @@ private function setDefaultMapBuilder(ContainerBuilder $container): void
             return;
         }
 
-        throw new \RuntimeException(
+        throw new RuntimeException(
             'No default map builder defined, please install an extension that provides ' .
             '"cyberspectrum_i18n.contao.default_map_builder".'
         );
diff --git a/src/DependencyInjection/CompilerPass/UpdateForRockSolidCustomElementPass.php b/src/DependencyInjection/CompilerPass/UpdateForRockSolidCustomElementPass.php
index 98a3437..deb3fda 100644
--- a/src/DependencyInjection/CompilerPass/UpdateForRockSolidCustomElementPass.php
+++ b/src/DependencyInjection/CompilerPass/UpdateForRockSolidCustomElementPass.php
@@ -1,23 +1,6 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\DependencyInjection\CompilerPass;
 
@@ -29,10 +12,7 @@
  */
 class UpdateForRockSolidCustomElementPass implements CompilerPassInterface
 {
-    /**
-     * {@inheritDoc}
-     */
-    public function process(ContainerBuilder $container)
+    public function process(ContainerBuilder $container): void
     {
         $extractor = $container->getDefinition('cyberspectrum_i18n.contao.extractor.tl_content.headline');
         $extractor->addTag(CollectExtractorConditionsPass::TAG_CONTAO_EXTRACTOR_CONDITION, [
diff --git a/src/DependencyInjection/CyberSpectrumI18NContaoExtension.php b/src/DependencyInjection/CyberSpectrumI18NContaoExtension.php
index 5fb4c49..538e421 100644
--- a/src/DependencyInjection/CyberSpectrumI18NContaoExtension.php
+++ b/src/DependencyInjection/CyberSpectrumI18NContaoExtension.php
@@ -1,23 +1,6 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\DependencyInjection;
 
@@ -28,6 +11,10 @@
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Extension\Extension;
 use Symfony\Component\DependencyInjection\Loader\YamlFileLoader;
+use Terminal42\ChangeLanguage\Terminal42ChangeLanguageBundle;
+
+use function array_key_exists;
+use function in_array;
 
 /**
  * This is the class that loads and manages the bundle configuration
@@ -37,15 +24,20 @@ class CyberSpectrumI18NContaoExtension extends Extension
     /**
      * {@inheritDoc}
      */
-    public function load(array $configs, ContainerBuilder $container)
+    public function load(array $configs, ContainerBuilder $container): void
     {
         $loader = new YamlFileLoader($container, new FileLocator(__DIR__ . '/../Resources/config'));
         $loader->load('contao/services.yml');
         $loader->load('contao/extractor.yml');
+        /** @psalm-suppress UndefinedClass - we do not need this class, this check is for feature detection only */
         if ($this->hasBundle(RockSolidCustomElementsBundle::class, $container)) {
             $loader->load('contao/rock-solid-custom-elements.yml');
         }
-        if ($this->hasBundle('changelanguage', $container)) {
+        /** @psalm-suppress UndefinedClass - we do not need this class, this check is for feature detection only */
+        if (
+            $this->hasBundle('changelanguage', $container)
+            || $this->hasBundle(Terminal42ChangeLanguageBundle::class, $container)
+        ) {
             $loader->load('contao/terminal42-change-language.yml');
         }
         // Only activate if MetaModels bundle present.
@@ -59,12 +51,15 @@ public function load(array $configs, ContainerBuilder $container)
      *
      * @param string           $class     The bundle class or bundle name.
      * @param ContainerBuilder $container The container builder.
-     *
-     * @return bool
      */
     private function hasBundle(string $class, ContainerBuilder $container): bool
     {
-        if (\in_array($class, $bundles = $container->getParameter('kernel.bundles'), true)) {
+        /**
+         * @var array<string, string> $bundles
+         * @psalm-suppress UndefinedDocblockClass - UnitEnum is added in PHP 8.1 and therefore throws in PHP 7.4.
+         */
+        $bundles = $container->getParameter('kernel.bundles');
+        if (in_array($class, $bundles, true)) {
             return true;
         }
 
diff --git a/src/FormType/InspectMappingFormType.php b/src/FormType/InspectMappingFormType.php
index 80e2b90..fcc7b84 100644
--- a/src/FormType/InspectMappingFormType.php
+++ b/src/FormType/InspectMappingFormType.php
@@ -1,23 +1,6 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\FormType;
 
@@ -33,19 +16,11 @@
  */
 class InspectMappingFormType extends AbstractType
 {
-    /**
-     * The Contao map builder.
-     *
-     * @var MapBuilderInterface
-     */
-    private $mapBuilder;
+    /** The Contao map builder. */
+    private MapBuilderInterface $mapBuilder;
 
-    /**
-     * The Contao token name.
-     *
-     * @var string
-     */
-    private $tokenName;
+    /** The Contao token name. */
+    private string $tokenName;
 
     /**
      * Create a new instance.
@@ -62,7 +37,7 @@ public function __construct(MapBuilderInterface $mapBuilder, string $tokenName)
     /**
      * {@inheritDoc}
      */
-    public function buildForm(FormBuilderInterface $builder, array $options)
+    public function buildForm(FormBuilderInterface $builder, array $options): void
     {
         $languages = [];
         foreach ($this->mapBuilder->getSupportedLanguages() as $language) {
@@ -78,7 +53,7 @@ public function buildForm(FormBuilderInterface $builder, array $options)
     /**
      * {@inheritdoc}
      */
-    public function configureOptions(OptionsResolver $resolver)
+    public function configureOptions(OptionsResolver $resolver): void
     {
         $resolver->setDefaults([
             'csrf_field_name' => 'REQUEST_TOKEN',
@@ -86,10 +61,7 @@ public function configureOptions(OptionsResolver $resolver)
         ]);
     }
 
-    /**
-     * {@inheritDoc}
-     */
-    public function getBlockPrefix()
+    public function getBlockPrefix(): string
     {
         return '';
     }
diff --git a/tests/ContaoManager/PluginTest.php b/tests/ContaoManager/PluginTest.php
index a55913e..6164168 100644
--- a/tests/ContaoManager/PluginTest.php
+++ b/tests/ContaoManager/PluginTest.php
@@ -1,23 +1,6 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\Test\ContaoManager;
 
@@ -35,28 +18,21 @@
 use Symfony\Component\HttpKernel\KernelInterface;
 use Symfony\Component\Routing\RouteCollection;
 
-/**
- * This tests the plugin.
- *
- * @covers \CyberSpectrum\I18N\ContaoBundle\ContaoManager\Plugin
- */
+use function realpath;
+
+/** @covers \CyberSpectrum\I18N\ContaoBundle\ContaoManager\Plugin */
 class PluginTest extends TestCase
 {
-    /**
-     * Test
-     *
-     * @return void
-     */
     public function testGetBundles(): void
     {
         $plugin  = new Plugin();
         $bundles = $plugin->getBundles($this->getMockForAbstractClass(ParserInterface::class));
 
-        $this->assertCount(2, $bundles);
+        self::assertCount(2, $bundles);
         /** @var ConfigInterface $bundle */
         $bundle = $bundles[0];
-        $this->assertSame(CyberSpectrumI18NContaoBundle::class, $bundle->getName());
-        $this->assertSame(
+        self::assertSame(CyberSpectrumI18NContaoBundle::class, $bundle->getName());
+        self::assertSame(
             [
                 ContaoCoreBundle::class,
                 CyberSpectrumI18NBundle::class,
@@ -66,14 +42,9 @@ public function testGetBundles(): void
             $bundle->getLoadAfter()
         );
         $bundle = $bundles[1];
-        $this->assertSame(CyberSpectrumI18NBundle::class, $bundle->getName());
+        self::assertSame(CyberSpectrumI18NBundle::class, $bundle->getName());
     }
 
-    /**
-     * Test
-     *
-     * @return void
-     */
     public function testRegisterContainerConfiguration(): void
     {
         $plugin  = new Plugin();
@@ -86,11 +57,6 @@ public function testRegisterContainerConfiguration(): void
         $plugin->registerContainerConfiguration($loader, []);
     }
 
-    /**
-     * Test
-     *
-     * @return void
-     */
     public function testGetRouteCollection(): void
     {
         $plugin   = new Plugin();
@@ -108,7 +74,7 @@ public function testGetRouteCollection(): void
             ->with($basePath . '/../Resources/config/contao/routing.yml')
             ->willReturn($collection = $this->getMockBuilder(RouteCollection::class)->getMock());
 
-        $this->assertSame($collection, $plugin->getRouteCollection(
+        self::assertSame($collection, $plugin->getRouteCollection(
             $resolver,
             $this->getMockForAbstractClass(KernelInterface::class)
         ));
diff --git a/tests/CyberSpectrumI18NContaoBundleTest.php b/tests/CyberSpectrumI18NContaoBundleTest.php
index f4ed970..128acfd 100644
--- a/tests/CyberSpectrumI18NContaoBundleTest.php
+++ b/tests/CyberSpectrumI18NContaoBundleTest.php
@@ -1,23 +1,6 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\Test;
 
@@ -32,18 +15,16 @@
 use Symfony\Component\DependencyInjection\Compiler\PassConfig;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 
-/**
- * This tests the bundle.
- *
- * @covers \CyberSpectrum\I18N\ContaoBundle\CyberSpectrumI18NContaoBundle
- */
+use function func_get_args;
+
+/** @covers \CyberSpectrum\I18N\ContaoBundle\CyberSpectrumI18NContaoBundle */
 class CyberSpectrumI18NContaoBundleTest extends TestCase
 {
     public function testBuild(): void
     {
         $container = $this
             ->getMockBuilder(ContainerBuilder::class)
-            ->setMethods(['addCompilerPass'])
+            ->onlyMethods(['addCompilerPass'])
             ->getMock();
 
         $arguments = [];
@@ -58,13 +39,13 @@ public function testBuild(): void
 
         $bundle->build($container);
 
-        $this->assertInstanceOf(CollectContaoExtractorsPass::class, $arguments[0][0]);
-        $this->assertInstanceOf(CollectExtractorConditionsPass::class, $arguments[1][0]);
-        $this->assertInstanceOf(CollectMetaModelAttributeHandlerPass::class, $arguments[2][0]);
-        $this->assertInstanceOf(SetDefaultsPass::class, $arguments[3][0]);
-        $this->assertInstanceOf(UpdateForRockSolidCustomElementPass::class, $arguments[4][0]);
-        $this->assertSame(PassConfig::TYPE_BEFORE_OPTIMIZATION, $arguments[4][1]);
-        $this->assertSame(10, $arguments[4][2]);
-        $this->assertInstanceOf(RegisterDictionaryTypesPass::class, $arguments[5][0]);
+        self::assertInstanceOf(CollectContaoExtractorsPass::class, $arguments[0][0]);
+        self::assertInstanceOf(CollectExtractorConditionsPass::class, $arguments[1][0]);
+        self::assertInstanceOf(CollectMetaModelAttributeHandlerPass::class, $arguments[2][0]);
+        self::assertInstanceOf(SetDefaultsPass::class, $arguments[3][0]);
+        self::assertInstanceOf(UpdateForRockSolidCustomElementPass::class, $arguments[4][0]);
+        self::assertSame(PassConfig::TYPE_BEFORE_OPTIMIZATION, $arguments[4][1]);
+        self::assertSame(10, $arguments[4][2]);
+        self::assertInstanceOf(RegisterDictionaryTypesPass::class, $arguments[5][0]);
     }
 }
diff --git a/tests/DependencyInjection/CompilerPass/CollectContaoExtractorsPassTest.php b/tests/DependencyInjection/CompilerPass/CollectContaoExtractorsPassTest.php
index 09d1406..d40ec90 100644
--- a/tests/DependencyInjection/CompilerPass/CollectContaoExtractorsPassTest.php
+++ b/tests/DependencyInjection/CompilerPass/CollectContaoExtractorsPassTest.php
@@ -1,23 +1,6 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\Test\DependencyInjection\CompilerPass;
 
@@ -25,23 +8,17 @@
 use CyberSpectrum\I18N\Contao\ExtractorFactory;
 use CyberSpectrum\I18N\ContaoBundle\DependencyInjection\CompilerPass\CollectContaoExtractorsPass;
 use PHPUnit\Framework\TestCase;
+use RuntimeException;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Definition;
 use Symfony\Component\DependencyInjection\Reference;
 use Symfony\Component\DependencyInjection\ServiceLocator;
 
-/**
- * This tests the service collector pass.
- *
- * @covers \CyberSpectrum\I18N\ContaoBundle\DependencyInjection\CompilerPass\CollectContaoExtractorsPass
- */
+use function array_keys;
+
+/** @covers \CyberSpectrum\I18N\ContaoBundle\DependencyInjection\CompilerPass\CollectContaoExtractorsPass */
 class CollectContaoExtractorsPassTest extends TestCase
 {
-    /**
-     * Test.
-     *
-     * @return void
-     */
     public function testCollectExtractors(): void
     {
         $container = new ContainerBuilder();
@@ -70,20 +47,15 @@ public function testCollectExtractors(): void
 
         $extractorList = $extractorContainer->getArgument(0);
 
-        $this->assertSame(
+        self::assertSame(
             ['tl_something' => ['service']],
             $container->getParameter('cyberspectrum_i18n.contao.extractors')
         );
-        $this->assertSame(['service'], \array_keys($extractorList));
-        $this->assertInstanceOf(Reference::class, $extractorList['service']);
-        $this->assertSame('service', (string) $extractorList['service']);
+        self::assertSame(['service'], array_keys($extractorList));
+        self::assertInstanceOf(Reference::class, $extractorList['service']);
+        self::assertSame('service', (string) $extractorList['service']);
     }
 
-    /**
-     * Test.
-     *
-     * @return void
-     */
     public function testCollectExtractorsThrowsForServiceWithoutTableName(): void
     {
         $container = new ContainerBuilder();
@@ -103,7 +75,7 @@ public function testCollectExtractorsThrowsForServiceWithoutTableName(): void
             ]
         );
 
-        $this->expectException(\RuntimeException::class);
+        $this->expectException(RuntimeException::class);
         $this->expectExceptionMessage('Tagged service "service" has no table name.');
 
         $servicePass = new CollectContaoExtractorsPass();
diff --git a/tests/DependencyInjection/CompilerPass/CollectExtractorConditionsPassTest.php b/tests/DependencyInjection/CompilerPass/CollectExtractorConditionsPassTest.php
index 3bcccbe..f899951 100644
--- a/tests/DependencyInjection/CompilerPass/CollectExtractorConditionsPassTest.php
+++ b/tests/DependencyInjection/CompilerPass/CollectExtractorConditionsPassTest.php
@@ -1,23 +1,6 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\Test\DependencyInjection\CompilerPass;
 
@@ -27,22 +10,16 @@
 use CyberSpectrum\I18N\Contao\Extractor\StringExtractorInterface;
 use CyberSpectrum\I18N\ContaoBundle\DependencyInjection\CompilerPass\CollectExtractorConditionsPass;
 use PHPUnit\Framework\TestCase;
+use RuntimeException;
 use Symfony\Component\DependencyInjection\ContainerBuilder;
 use Symfony\Component\DependencyInjection\Definition;
 use Symfony\Component\DependencyInjection\Reference;
 
-/**
- * This tests the service collector pass.
- *
- * @covers \CyberSpectrum\I18N\ContaoBundle\DependencyInjection\CompilerPass\CollectExtractorConditionsPass
- */
+use function get_class;
+
+/** @covers \CyberSpectrum\I18N\ContaoBundle\DependencyInjection\CompilerPass\CollectExtractorConditionsPass */
 class CollectExtractorConditionsPassTest extends TestCase
 {
-    /**
-     * Test.
-     *
-     * @return void
-     */
     public function testCollectStringExtractorInterface(): void
     {
         $container = new ContainerBuilder();
@@ -60,18 +37,13 @@ public function testCollectStringExtractorInterface(): void
         $servicePass = new CollectExtractorConditionsPass();
         $servicePass->process($container);
 
-        $this->assertTrue($container->has('service.conditional'));
+        self::assertTrue($container->has('service.conditional'));
         $service = $container->getDefinition('service.conditional');
-        $this->assertSame(['service', null, 0], $service->getDecoratedService());
-        $this->assertInstanceOf(Reference::class, $service->getArgument(0));
-        $this->assertSame('service.conditional.inner', (string) $service->getArgument(0));
+        self::assertSame(['service', null, 0], $service->getDecoratedService());
+        self::assertInstanceOf(Reference::class, $service->getArgument(0));
+        self::assertSame('service.conditional.inner', (string) $service->getArgument(0));
     }
 
-    /**
-     * Test.
-     *
-     * @return void
-     */
     public function testCollectMultiStringExtractorInterface(): void
     {
         $container = new ContainerBuilder();
@@ -89,18 +61,13 @@ public function testCollectMultiStringExtractorInterface(): void
         $servicePass = new CollectExtractorConditionsPass();
         $servicePass->process($container);
 
-        $this->assertTrue($container->has('service.conditional'));
+        self::assertTrue($container->has('service.conditional'));
         $service = $container->getDefinition('service.conditional');
-        $this->assertSame(['service', null, 0], $service->getDecoratedService());
-        $this->assertInstanceOf(Reference::class, $service->getArgument(0));
-        $this->assertSame('service.conditional.inner', (string) $service->getArgument(0));
+        self::assertSame(['service', null, 0], $service->getDecoratedService());
+        self::assertInstanceOf(Reference::class, $service->getArgument(0));
+        self::assertSame('service.conditional.inner', (string) $service->getArgument(0));
     }
 
-    /**
-     * Test.
-     *
-     * @return void
-     */
     public function testCollectUnknownExtractorInterfaceThrows(): void
     {
         $container = new ContainerBuilder();
@@ -115,7 +82,7 @@ public function testCollectUnknownExtractorInterfaceThrows(): void
         $container->addDefinitions(['service' => $tagged]);
         unset($tagged);
 
-        $this->expectException(\RuntimeException::class);
+        $this->expectException(RuntimeException::class);
         $this->expectExceptionMessage('Class ' . $class . ' does not implement '
             . ConditionalExtractorInterface::class . ' - can not apply conditions (service: service).');
 
@@ -123,11 +90,6 @@ public function testCollectUnknownExtractorInterfaceThrows(): void
         $servicePass->process($container);
     }
 
-    /**
-     * Test.
-     *
-     * @return void
-     */
     public function testDoesNotDecorateTwice(): void
     {
         $container = new ContainerBuilder();
@@ -146,14 +108,9 @@ public function testDoesNotDecorateTwice(): void
         $servicePass = new CollectExtractorConditionsPass();
         $servicePass->process($container);
 
-        $this->assertSame($definition, $container->getDefinition('service.conditional'));
+        self::assertSame($definition, $container->getDefinition('service.conditional'));
     }
 
-    /**
-     * Test.
-     *
-     * @return void
-     */
     public function testDoesNotDecorateConditionalService(): void
     {
         $container = new ContainerBuilder();
@@ -168,18 +125,13 @@ public function testDoesNotDecorateConditionalService(): void
         $servicePass = new CollectExtractorConditionsPass();
         $servicePass->process($container);
 
-        $this->assertFalse($container->hasDefinition('service.conditional'));
-        $this->assertSame($tagged, $container->getDefinition('service'));
-        $this->assertCount(1, $calls = $container->getDefinition('service')->getMethodCalls());
-        $this->assertSame('setCondition', $calls[0][0]);
-        $this->assertInstanceOf(Reference::class, $calls[0][1][0]);
+        self::assertFalse($container->hasDefinition('service.conditional'));
+        self::assertSame($tagged, $container->getDefinition('service'));
+        self::assertCount(1, $calls = $container->getDefinition('service')->getMethodCalls());
+        self::assertSame('setCondition', $calls[0][0]);
+        self::assertInstanceOf(Reference::class, $calls[0][1][0]);
     }
 
-    /**
-     * Test.
-     *
-     * @return void
-     */
     public function testCollectExtractorsThrowsForTagWithoutConditionType(): void
     {
         $container = new ContainerBuilder();
@@ -188,18 +140,13 @@ public function testCollectExtractorsThrowsForTagWithoutConditionType(): void
         $tagged->addTag(CollectExtractorConditionsPass::TAG_CONTAO_EXTRACTOR_CONDITION);
         $container->addDefinitions(['service' => $tagged]);
 
-        $this->expectException(\RuntimeException::class);
+        $this->expectException(RuntimeException::class);
         $this->expectExceptionMessage('No type given for condition of service: service.');
 
         $servicePass = new CollectExtractorConditionsPass();
         $servicePass->process($container);
     }
 
-    /**
-     * Test.
-     *
-     * @return void
-     */
     public function testCollectExtractorsThrowsForTagWithoutExpression(): void
     {
         $container = new ContainerBuilder();
@@ -208,18 +155,13 @@ public function testCollectExtractorsThrowsForTagWithoutExpression(): void
         $tagged->addTag(CollectExtractorConditionsPass::TAG_CONTAO_EXTRACTOR_CONDITION, ['type' => 'expression']);
         $container->addDefinitions(['service' => $tagged]);
 
-        $this->expectException(\RuntimeException::class);
+        $this->expectException(RuntimeException::class);
         $this->expectExceptionMessage('Expression missing in tag for: service');
 
         $servicePass = new CollectExtractorConditionsPass();
         $servicePass->process($container);
     }
 
-    /**
-     * Test.
-     *
-     * @return void
-     */
     public function testCollectExtractorsThrowsForTagWithUnknownType(): void
     {
         $container = new ContainerBuilder();
@@ -228,7 +170,7 @@ public function testCollectExtractorsThrowsForTagWithUnknownType(): void
         $tagged->addTag(CollectExtractorConditionsPass::TAG_CONTAO_EXTRACTOR_CONDITION, ['type' => '-unknown-']);
         $container->addDefinitions(['service' => $tagged]);
 
-        $this->expectException(\RuntimeException::class);
+        $this->expectException(RuntimeException::class);
         $this->expectExceptionMessage('Unknown condition tag: {"type":"-unknown-"}');
 
         $servicePass = new CollectExtractorConditionsPass();
diff --git a/tests/DependencyInjection/CyberSpectrumI18NContaoExtensionTest.php b/tests/DependencyInjection/CyberSpectrumI18NContaoExtensionTest.php
index 0da36af..fed79e0 100644
--- a/tests/DependencyInjection/CyberSpectrumI18NContaoExtensionTest.php
+++ b/tests/DependencyInjection/CyberSpectrumI18NContaoExtensionTest.php
@@ -1,23 +1,6 @@
 <?php
 
-/**
- * This file is part of cyberspectrum/i18n-contao-bundle.
- *
- * (c) 2018 CyberSpectrum.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- *
- * This project is provided in good faith and hope to be usable by anyone.
- *
- * @package    cyberspectrum/i18n-contao-bundle
- * @author     Christian Schiffler <c.schiffler@cyberspectrum.de>
- * @copyright  2018 CyberSpectrum.
- * @license    https://github.com/cyberspectrum/i18n-contao-bundle/blob/master/LICENSE MIT
- * @filesource
- */
-
-declare(strict_types = 1);
+declare(strict_types=1);
 
 namespace CyberSpectrum\I18N\ContaoBundle\Test\DependencyInjection;
 
@@ -68,14 +51,14 @@ public function testLoad(): void
                 $class = $serviceId;
             }
 
-            $this->assertTrue(
+            self::assertTrue(
                 class_exists($class) || interface_exists($class),
                 'Class ' . $class . ' does not exist for ' . $serviceId
             );
         }
 
         // Assert we get all files loaded.
-        $this->assertSame([
+        self::assertSame([
             realpath(__DIR__ . '/../../src/Resources/config/contao/services.yml'),
             realpath(__DIR__ . '/../../src/Resources/config/contao/extractor.yml'),
             realpath(__DIR__ . '/../../src/Resources/config/contao/rock-solid-custom-elements.yml'),
@@ -105,7 +88,7 @@ public function testLoadSkipsConfigForUnknownBundles(): void
             }
         }
 
-        $this->assertSame([
+        self::assertSame([
             realpath(__DIR__ . '/../../src/Resources/config/contao/services.yml'),
             realpath(__DIR__ . '/../../src/Resources/config/contao/extractor.yml'),
         ], $files);