diff --git a/composer.json b/composer.json
index 1167cdd..5886ca7 100644
--- a/composer.json
+++ b/composer.json
@@ -28,7 +28,7 @@
     },
     "require-dev": {
         "phpunit/phpunit": "^9.6",
-        "sigwin/infra": "~1.5.0"
+        "sigwin/infra": "~1.6.0"
     },
     "conflict": {
         "nikic/php-parser": "< 4.14",
diff --git a/psalm.xml.dist b/psalm.xml.dist
index b1db58c..5f892b9 100644
--- a/psalm.xml.dist
+++ b/psalm.xml.dist
@@ -11,7 +11,7 @@
        findUnusedPsalmSuppress="true"
        findUnusedVariablesAndParams="true"
        limitMethodComplexity="true"
-       restrictReturnTypes="true"
+       restrictReturnTypes="false"
        strictBinaryOperands="true">
     <projectFiles>
         <directory name="./"/>
diff --git a/src/Bridge/Symfony/HttpKernel/Fragment/RelativeUrlInlineFragmentRenderer.php b/src/Bridge/Symfony/HttpKernel/Fragment/RelativeUrlInlineFragmentRenderer.php
index 9a49cce..b038ac3 100644
--- a/src/Bridge/Symfony/HttpKernel/Fragment/RelativeUrlInlineFragmentRenderer.php
+++ b/src/Bridge/Symfony/HttpKernel/Fragment/RelativeUrlInlineFragmentRenderer.php
@@ -32,8 +32,6 @@ public function __construct(InlineFragmentRenderer $fragmentRenderer, UrlGenerat
 
         /**
          * @psalm-param string|\Symfony\Component\HttpKernel\Controller\ControllerReference $uri
-         *
-         * @param mixed $uri
          */
         public function render($uri, Request $request, array $options = []): \Symfony\Component\HttpFoundation\Response
         {
diff --git a/src/Bridge/Symfony/Serializer/Normalizer/CollectionNormalizer.php b/src/Bridge/Symfony/Serializer/Normalizer/CollectionNormalizer.php
index 1149158..33f704d 100644
--- a/src/Bridge/Symfony/Serializer/Normalizer/CollectionNormalizer.php
+++ b/src/Bridge/Symfony/Serializer/Normalizer/CollectionNormalizer.php
@@ -36,7 +36,7 @@ public function __construct(ExpressionLanguage $expressionLanguage, ClassMetadat
         $this->classMetadataFactory = $classMetadataFactory;
     }
 
-    public function denormalize(mixed $data, string $type, string $format = null, array $context = []): Collection
+    public function denormalize(mixed $data, string $type, ?string $format = null, array $context = []): Collection
     {
         $type = mb_substr($type, 0, -2);
         if ($data === null) {
@@ -55,7 +55,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
         return new ReadOnlyCollection($this->expressionLanguage, $this->getProperties($type), $denormalized);
     }
 
-    public function supportsDenormalization(mixed $data, string $type, string $format = null, array $context = null): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null, ?array $context = null): bool
     {
         return str_ends_with($type, '[]');
     }
diff --git a/src/Bridge/Symfony/Serializer/Normalizer/ExpressionNormalizer.php b/src/Bridge/Symfony/Serializer/Normalizer/ExpressionNormalizer.php
index 0b44d03..e05c624 100644
--- a/src/Bridge/Symfony/Serializer/Normalizer/ExpressionNormalizer.php
+++ b/src/Bridge/Symfony/Serializer/Normalizer/ExpressionNormalizer.php
@@ -28,7 +28,7 @@ public function __construct(ExpressionLanguage $expressionLanguage, DatabaseProv
         $this->databaseProvider = $databaseProvider;
     }
 
-    public function denormalize(mixed $data, string $type, string $format = null, array $context = [])
+    public function denormalize(mixed $data, string $type, ?string $format = null, array $context = [])
     {
         /** @var string $data */
         $value = $this->expressionLanguage->evaluate(mb_substr($data, 2), [
@@ -47,7 +47,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
         return $value;
     }
 
-    public function supportsDenormalization(mixed $data, string $type, string $format = null): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null): bool
     {
         return \is_string($data) && str_starts_with($data, '@=');
     }
diff --git a/src/Bridge/Symfony/Serializer/Normalizer/LocalizingNormalizer.php b/src/Bridge/Symfony/Serializer/Normalizer/LocalizingNormalizer.php
index 2ed793d..11ff452 100644
--- a/src/Bridge/Symfony/Serializer/Normalizer/LocalizingNormalizer.php
+++ b/src/Bridge/Symfony/Serializer/Normalizer/LocalizingNormalizer.php
@@ -31,7 +31,7 @@ public function __construct(array $classes)
         $this->classes = $classes;
     }
 
-    public function denormalize(mixed $data, string $type, string $format = null, array $context = []): mixed
+    public function denormalize(mixed $data, string $type, ?string $format = null, array $context = []): mixed
     {
         if (isset($this->classes[$type])) {
             $locale = $context[LocaleContext::LOCALE];
@@ -55,7 +55,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
         return $this->denormalizer->denormalize($data, $type, $format, $context);
     }
 
-    public function supportsDenormalization(mixed $data, string $type, string $format = null, array $context = null): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null, ?array $context = null): bool
     {
         return isset($this->classes[$type]) && ($context[self::LOCALIZING_NORMALIZER_LAST_TYPE] ?? null) !== $type;
     }
diff --git a/src/Bridge/Symfony/Serializer/Normalizer/ResourceLocatorNormalizer.php b/src/Bridge/Symfony/Serializer/Normalizer/ResourceLocatorNormalizer.php
index f022ab1..e46828b 100644
--- a/src/Bridge/Symfony/Serializer/Normalizer/ResourceLocatorNormalizer.php
+++ b/src/Bridge/Symfony/Serializer/Normalizer/ResourceLocatorNormalizer.php
@@ -26,7 +26,7 @@ public function __construct(FileLocatorInterface $locator)
         $this->locator = $locator;
     }
 
-    public function denormalize(mixed $data, string $type, string $format = null, array $context = [])
+    public function denormalize(mixed $data, string $type, ?string $format = null, array $context = [])
     {
         if (\is_string($data) === false) {
             throw new \LogicException('String expected');
@@ -35,7 +35,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
         return $this->locator->locate($data);
     }
 
-    public function supportsDenormalization(mixed $data, string $type, string $format = null): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null): bool
     {
         return $type === Resource::class && \is_string($data) && str_starts_with($data, '@');
     }
diff --git a/src/Storage/FilesystemStorage.php b/src/Storage/FilesystemStorage.php
index f9a8327..ae3c15e 100644
--- a/src/Storage/FilesystemStorage.php
+++ b/src/Storage/FilesystemStorage.php
@@ -100,7 +100,6 @@ public static function resolveOptions(array $options): array
         $resolver->setRequired(['root']);
         $resolver->setAllowedTypes('root', ['array', 'string']);
         $resolver->setAllowedTypes('names', ['array', 'string']);
-        /** @psalm-suppress UnusedClosureParam */
         $resolver->setNormalizer('root', static function (OptionsResolver $resolver, array|string $value): array {
             if (\is_string($value)) {
                 $value = [$value];
diff --git a/tests/unit/GeneratorTest.php b/tests/unit/GeneratorTest.php
index 6eaac7b..42172ca 100644
--- a/tests/unit/GeneratorTest.php
+++ b/tests/unit/GeneratorTest.php
@@ -104,7 +104,7 @@ private function generate(Generator $generator): void
             $called = true;
         });
         if (! $called) {
-            static::fail('Callback not called');
+            self::fail('Callback not called');
         }
     }
 
@@ -121,12 +121,12 @@ private function mockUrlGenerator(string $baseUrl, array $routes, mixed $indexFi
     {
         $requestContext = $this->getMockBuilder(RequestContext::class)->getMock();
         $requestContext
-            ->expects(static::once())
+            ->expects(self::once())
             ->method('getBaseUrl')
             ->willReturn($baseUrl)
         ;
         $requestContext
-            ->expects(static::once())
+            ->expects(self::once())
             ->method('getParameter')
             ->with('index-file')
             ->willReturn($indexFile)
@@ -134,7 +134,7 @@ private function mockUrlGenerator(string $baseUrl, array $routes, mixed $indexFi
 
         $urlGenerator = $this->getMockBuilder(UrlGeneratorInterface::class)->getMock();
         $urlGenerator
-            ->expects(static::once())
+            ->expects(self::once())
             ->method('getContext')
             ->willReturn($requestContext)
         ;
@@ -145,7 +145,7 @@ private function mockUrlGenerator(string $baseUrl, array $routes, mixed $indexFi
         }
 
         $urlGenerator
-            ->expects(static::exactly(\count($routes)))
+            ->expects(self::exactly(\count($routes)))
             ->method('generate')
             ->withConsecutive(...$remapped)
             ->willReturn('/////')
@@ -158,21 +158,21 @@ private function mockKernel(string $baseUrl, string|false $body, int $status = 2
     {
         $response = $this->getMockBuilder(Response::class)->getMock();
         $response
-            ->expects(static::once())
+            ->expects(self::once())
             ->method('getStatusCode')
             ->willReturn($status)
         ;
         $response
-            ->expects(static::once())
+            ->expects(self::once())
             ->method('getContent')
             ->willReturn($body)
         ;
 
         $kernel = $this->getMockBuilder(KernelInterface::class)->getMock();
         $kernel
-            ->expects(static::once())
+            ->expects(self::once())
             ->method('handle')
-            ->with(static::callback(static function (\Symfony\Component\HttpFoundation\Request $request) use ($baseUrl): bool {
+            ->with(self::callback(static function (\Symfony\Component\HttpFoundation\Request $request) use ($baseUrl): bool {
                 return $request->getUri() === 'http://localhost/'.$baseUrl;
             }))
             ->willReturn($response)
@@ -185,7 +185,7 @@ private function mockFilesystem(?string $path, string $content): Filesystem
     {
         $filesystem = $this->getMockBuilder(Filesystem::class)->getMock();
         $filesystem
-            ->expects(static::once())
+            ->expects(self::once())
             ->method('dumpFile')
             ->with($path, $content)
         ;