diff --git a/DataCollector/SerializerDataCollector.php b/DataCollector/SerializerDataCollector.php
index 9dd1752fa..671239d28 100644
--- a/DataCollector/SerializerDataCollector.php
+++ b/DataCollector/SerializerDataCollector.php
@@ -33,7 +33,7 @@ public function reset(): void
         $this->collected = [];
     }
 
-    public function collect(Request $request, Response $response, \Throwable $exception = null): void
+    public function collect(Request $request, Response $response, ?\Throwable $exception = null): void
     {
         // Everything is collected during the request, and formatted on kernel terminate.
     }
diff --git a/Debug/TraceableNormalizer.php b/Debug/TraceableNormalizer.php
index 4bdd3f7b4..fc4db40ad 100644
--- a/Debug/TraceableNormalizer.php
+++ b/Debug/TraceableNormalizer.php
@@ -48,7 +48,7 @@ public function getSupportedTypes(?string $format): array
         return $this->normalizer->getSupportedTypes($format);
     }
 
-    public function normalize(mixed $object, string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
+    public function normalize(mixed $object, ?string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
     {
         if (!$this->normalizer instanceof NormalizerInterface) {
             throw new \BadMethodCallException(sprintf('The "%s()" method cannot be called as nested normalizer doesn\'t implements "%s".', __METHOD__, NormalizerInterface::class));
@@ -65,7 +65,7 @@ public function normalize(mixed $object, string $format = null, array $context =
         return $normalized;
     }
 
-    public function supportsNormalization(mixed $data, string $format = null, array $context = []): bool
+    public function supportsNormalization(mixed $data, ?string $format = null, array $context = []): bool
     {
         if (!$this->normalizer instanceof NormalizerInterface) {
             return false;
@@ -74,7 +74,7 @@ public function supportsNormalization(mixed $data, string $format = null, array
         return $this->normalizer->supportsNormalization($data, $format, $context);
     }
 
-    public function denormalize(mixed $data, string $type, string $format = null, array $context = []): mixed
+    public function denormalize(mixed $data, string $type, ?string $format = null, array $context = []): mixed
     {
         if (!$this->normalizer instanceof DenormalizerInterface) {
             throw new \BadMethodCallException(sprintf('The "%s()" method cannot be called as nested normalizer doesn\'t implements "%s".', __METHOD__, DenormalizerInterface::class));
@@ -91,7 +91,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
         return $denormalized;
     }
 
-    public function supportsDenormalization(mixed $data, string $type, string $format = null, array $context = []): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null, array $context = []): bool
     {
         if (!$this->normalizer instanceof DenormalizerInterface) {
             return false;
diff --git a/Debug/TraceableSerializer.php b/Debug/TraceableSerializer.php
index 2a8e96c7a..2e375e08d 100644
--- a/Debug/TraceableSerializer.php
+++ b/Debug/TraceableSerializer.php
@@ -69,7 +69,7 @@ public function deserialize(mixed $data, string $type, string $format, array $co
         return $result;
     }
 
-    public function normalize(mixed $object, string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
+    public function normalize(mixed $object, ?string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
     {
         $context[self::DEBUG_TRACE_ID] = $traceId = uniqid();
 
@@ -84,7 +84,7 @@ public function normalize(mixed $object, string $format = null, array $context =
         return $result;
     }
 
-    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
     {
         $context[self::DEBUG_TRACE_ID] = $traceId = uniqid();
 
@@ -139,12 +139,12 @@ public function getSupportedTypes(?string $format): array
         return $this->serializer->getSupportedTypes($format);
     }
 
-    public function supportsNormalization(mixed $data, string $format = null, array $context = []): bool
+    public function supportsNormalization(mixed $data, ?string $format = null, array $context = []): bool
     {
         return $this->serializer->supportsNormalization($data, $format, $context);
     }
 
-    public function supportsDenormalization(mixed $data, string $type, string $format = null, array $context = []): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null, array $context = []): bool
     {
         return $this->serializer->supportsDenormalization($data, $type, $format, $context);
     }
diff --git a/Encoder/JsonEncoder.php b/Encoder/JsonEncoder.php
index 0d8bf8d09..dabb89c58 100644
--- a/Encoder/JsonEncoder.php
+++ b/Encoder/JsonEncoder.php
@@ -27,7 +27,7 @@ class JsonEncoder implements EncoderInterface, DecoderInterface
         JsonDecode::ASSOCIATIVE => true,
     ];
 
-    public function __construct(JsonEncode $encodingImpl = null, JsonDecode $decodingImpl = null, array $defaultContext = [])
+    public function __construct(?JsonEncode $encodingImpl = null, ?JsonDecode $decodingImpl = null, array $defaultContext = [])
     {
         $this->defaultContext = array_merge($this->defaultContext, $defaultContext);
         $this->encodingImpl = $encodingImpl ?? new JsonEncode($this->defaultContext);
diff --git a/Encoder/XmlEncoder.php b/Encoder/XmlEncoder.php
index 26ee3237c..7b177e49d 100644
--- a/Encoder/XmlEncoder.php
+++ b/Encoder/XmlEncoder.php
@@ -340,7 +340,7 @@ private function addXmlNamespaces(array $data, \DOMNode $node, \DOMDocument $doc
      *
      * @throws NotEncodableValueException
      */
-    private function buildXml(\DOMNode $parentNode, mixed $data, string $format, array $context, string $xmlRootNodeName = null): bool
+    private function buildXml(\DOMNode $parentNode, mixed $data, string $format, array $context, ?string $xmlRootNodeName = null): bool
     {
         $append = true;
         $removeEmptyTags = $context[self::REMOVE_EMPTY_TAGS] ?? $this->defaultContext[self::REMOVE_EMPTY_TAGS] ?? false;
@@ -414,7 +414,7 @@ private function buildXml(\DOMNode $parentNode, mixed $data, string $format, arr
     /**
      * Selects the type of node to create and appends it to the parent.
      */
-    private function appendNode(\DOMNode $parentNode, mixed $data, string $format, array $context, string $nodeName, string $key = null): bool
+    private function appendNode(\DOMNode $parentNode, mixed $data, string $format, array $context, string $nodeName, ?string $key = null): bool
     {
         $dom = $parentNode instanceof \DOMDocument ? $parentNode : $parentNode->ownerDocument;
         $node = $dom->createElement($nodeName);
diff --git a/Encoder/YamlEncoder.php b/Encoder/YamlEncoder.php
index 031a3105e..53ec93001 100644
--- a/Encoder/YamlEncoder.php
+++ b/Encoder/YamlEncoder.php
@@ -50,7 +50,7 @@ class YamlEncoder implements EncoderInterface, DecoderInterface
         self::YAML_FLAGS => 0,
     ];
 
-    public function __construct(Dumper $dumper = null, Parser $parser = null, array $defaultContext = [])
+    public function __construct(?Dumper $dumper = null, ?Parser $parser = null, array $defaultContext = [])
     {
         if (!class_exists(Dumper::class)) {
             throw new RuntimeException('The YamlEncoder class requires the "Yaml" component. Install "symfony/yaml" to use it.');
diff --git a/Exception/ExtraAttributesException.php b/Exception/ExtraAttributesException.php
index d681de419..24b031ae3 100644
--- a/Exception/ExtraAttributesException.php
+++ b/Exception/ExtraAttributesException.php
@@ -20,7 +20,7 @@ class ExtraAttributesException extends RuntimeException
 {
     public function __construct(
         private readonly array $extraAttributes,
-        \Throwable $previous = null,
+        ?\Throwable $previous = null,
     ) {
         $msg = sprintf('Extra attributes are not allowed ("%s" %s unknown).', implode('", "', $extraAttributes), \count($extraAttributes) > 1 ? 'are' : 'is');
 
diff --git a/Exception/MissingConstructorArgumentsException.php b/Exception/MissingConstructorArgumentsException.php
index ee8fcb5dc..ad3f5c82b 100644
--- a/Exception/MissingConstructorArgumentsException.php
+++ b/Exception/MissingConstructorArgumentsException.php
@@ -23,7 +23,7 @@ class MissingConstructorArgumentsException extends RuntimeException
     public function __construct(
         string $message,
         int $code = 0,
-        \Throwable $previous = null,
+        ?\Throwable $previous = null,
         private array $missingArguments = [],
         private ?string $class = null,
     ) {
diff --git a/Exception/NotNormalizableValueException.php b/Exception/NotNormalizableValueException.php
index 148c60ada..279be4127 100644
--- a/Exception/NotNormalizableValueException.php
+++ b/Exception/NotNormalizableValueException.php
@@ -27,7 +27,7 @@ class NotNormalizableValueException extends UnexpectedValueException
      *                                    safely to your user. In other words, avoid catching other exceptions and
      *                                    passing their message directly to this class.
      */
-    public static function createForUnexpectedDataType(string $message, mixed $data, array $expectedTypes, string $path = null, bool $useMessageForUser = false, int $code = 0, \Throwable $previous = null): self
+    public static function createForUnexpectedDataType(string $message, mixed $data, array $expectedTypes, ?string $path = null, bool $useMessageForUser = false, int $code = 0, ?\Throwable $previous = null): self
     {
         $self = new self($message, $code, $previous);
 
diff --git a/Extractor/ObjectPropertyListExtractor.php b/Extractor/ObjectPropertyListExtractor.php
index c237e13a7..8422b0786 100644
--- a/Extractor/ObjectPropertyListExtractor.php
+++ b/Extractor/ObjectPropertyListExtractor.php
@@ -21,7 +21,7 @@ final class ObjectPropertyListExtractor implements ObjectPropertyListExtractorIn
     private PropertyListExtractorInterface $propertyListExtractor;
     private \Closure $objectClassResolver;
 
-    public function __construct(PropertyListExtractorInterface $propertyListExtractor, callable $objectClassResolver = null)
+    public function __construct(PropertyListExtractorInterface $propertyListExtractor, ?callable $objectClassResolver = null)
     {
         $this->propertyListExtractor = $propertyListExtractor;
         $this->objectClassResolver = ($objectClassResolver ?? 'get_class')(...);
diff --git a/Mapping/AttributeMetadata.php b/Mapping/AttributeMetadata.php
index c77d07e5e..eaa14eb6e 100644
--- a/Mapping/AttributeMetadata.php
+++ b/Mapping/AttributeMetadata.php
@@ -110,7 +110,7 @@ public function getMaxDepth(): ?int
         return $this->maxDepth;
     }
 
-    public function setSerializedName(string $serializedName = null): void
+    public function setSerializedName(?string $serializedName = null): void
     {
         if (1 > \func_num_args()) {
             trigger_deprecation('symfony/serializer', '6.2', 'Calling "%s()" without any arguments is deprecated, pass null explicitly instead.', __METHOD__);
@@ -124,7 +124,7 @@ public function getSerializedName(): ?string
         return $this->serializedName;
     }
 
-    public function setSerializedPath(PropertyPath $serializedPath = null): void
+    public function setSerializedPath(?PropertyPath $serializedPath = null): void
     {
         $this->serializedPath = $serializedPath;
     }
diff --git a/Mapping/ClassMetadata.php b/Mapping/ClassMetadata.php
index 3a711634a..5cec14c91 100644
--- a/Mapping/ClassMetadata.php
+++ b/Mapping/ClassMetadata.php
@@ -44,7 +44,7 @@ class ClassMetadata implements ClassMetadataInterface
     /**
      * Constructs a metadata for the given class.
      */
-    public function __construct(string $class, ClassDiscriminatorMapping $classDiscriminatorMapping = null)
+    public function __construct(string $class, ?ClassDiscriminatorMapping $classDiscriminatorMapping = null)
     {
         $this->name = $class;
         $this->classDiscriminatorMapping = $classDiscriminatorMapping;
@@ -90,7 +90,7 @@ public function getClassDiscriminatorMapping(): ?ClassDiscriminatorMapping
         return $this->classDiscriminatorMapping;
     }
 
-    public function setClassDiscriminatorMapping(ClassDiscriminatorMapping $mapping = null): void
+    public function setClassDiscriminatorMapping(?ClassDiscriminatorMapping $mapping = null): void
     {
         if (1 > \func_num_args()) {
             trigger_deprecation('symfony/serializer', '6.2', 'Calling "%s()" without any arguments is deprecated, pass null explicitly instead.', __METHOD__);
diff --git a/NameConverter/AdvancedNameConverterInterface.php b/NameConverter/AdvancedNameConverterInterface.php
index 4e7ed504f..1e74f4d20 100644
--- a/NameConverter/AdvancedNameConverterInterface.php
+++ b/NameConverter/AdvancedNameConverterInterface.php
@@ -18,7 +18,7 @@
  */
 interface AdvancedNameConverterInterface extends NameConverterInterface
 {
-    public function normalize(string $propertyName, string $class = null, string $format = null, array $context = []): string;
+    public function normalize(string $propertyName, ?string $class = null, ?string $format = null, array $context = []): string;
 
-    public function denormalize(string $propertyName, string $class = null, string $format = null, array $context = []): string;
+    public function denormalize(string $propertyName, ?string $class = null, ?string $format = null, array $context = []): string;
 }
diff --git a/NameConverter/MetadataAwareNameConverter.php b/NameConverter/MetadataAwareNameConverter.php
index d1a0b28f2..64abd37d3 100644
--- a/NameConverter/MetadataAwareNameConverter.php
+++ b/NameConverter/MetadataAwareNameConverter.php
@@ -41,7 +41,7 @@ public function __construct(
     ) {
     }
 
-    public function normalize(string $propertyName, string $class = null, string $format = null, array $context = []): string
+    public function normalize(string $propertyName, ?string $class = null, ?string $format = null, array $context = []): string
     {
         if (null === $class) {
             return $this->normalizeFallback($propertyName, $class, $format, $context);
@@ -54,7 +54,7 @@ public function normalize(string $propertyName, string $class = null, string $fo
         return self::$normalizeCache[$class][$propertyName] ?? $this->normalizeFallback($propertyName, $class, $format, $context);
     }
 
-    public function denormalize(string $propertyName, string $class = null, string $format = null, array $context = []): string
+    public function denormalize(string $propertyName, ?string $class = null, ?string $format = null, array $context = []): string
     {
         if (null === $class) {
             return $this->denormalizeFallback($propertyName, $class, $format, $context);
@@ -86,7 +86,7 @@ private function getCacheValueForNormalization(string $propertyName, string $cla
         return $attributesMetadata[$propertyName]->getSerializedName() ?? null;
     }
 
-    private function normalizeFallback(string $propertyName, string $class = null, string $format = null, array $context = []): string
+    private function normalizeFallback(string $propertyName, ?string $class = null, ?string $format = null, array $context = []): string
     {
         return $this->fallbackNameConverter ? $this->fallbackNameConverter->normalize($propertyName, $class, $format, $context) : $propertyName;
     }
@@ -101,7 +101,7 @@ private function getCacheValueForDenormalization(string $propertyName, string $c
         return self::$attributesMetadataCache[$cacheKey][$propertyName] ?? null;
     }
 
-    private function denormalizeFallback(string $propertyName, string $class = null, string $format = null, array $context = []): string
+    private function denormalizeFallback(string $propertyName, ?string $class = null, ?string $format = null, array $context = []): string
     {
         return $this->fallbackNameConverter ? $this->fallbackNameConverter->denormalize($propertyName, $class, $format, $context) : $propertyName;
     }
diff --git a/Normalizer/AbstractNormalizer.php b/Normalizer/AbstractNormalizer.php
index 06c316eb0..a88544154 100644
--- a/Normalizer/AbstractNormalizer.php
+++ b/Normalizer/AbstractNormalizer.php
@@ -143,7 +143,7 @@ abstract class AbstractNormalizer implements NormalizerInterface, DenormalizerIn
     /**
      * Sets the {@link ClassMetadataFactoryInterface} to use.
      */
-    public function __construct(ClassMetadataFactoryInterface $classMetadataFactory = null, NameConverterInterface $nameConverter = null, array $defaultContext = [])
+    public function __construct(?ClassMetadataFactoryInterface $classMetadataFactory = null, ?NameConverterInterface $nameConverter = null, array $defaultContext = [])
     {
         $this->classMetadataFactory = $classMetadataFactory;
         $this->nameConverter = $nameConverter;
@@ -201,7 +201,7 @@ protected function isCircularReference(object $object, array &$context): bool
      *
      * @throws CircularReferenceException
      */
-    protected function handleCircularReference(object $object, string $format = null, array $context = []): mixed
+    protected function handleCircularReference(object $object, ?string $format = null, array $context = []): mixed
     {
         $circularReferenceHandler = $context[self::CIRCULAR_REFERENCE_HANDLER] ?? $this->defaultContext[self::CIRCULAR_REFERENCE_HANDLER];
         if ($circularReferenceHandler) {
@@ -270,7 +270,7 @@ protected function getGroups(array $context): array
      *
      * @return bool
      */
-    protected function isAllowedAttribute(object|string $classOrObject, string $attribute, string $format = null, array $context = [])
+    protected function isAllowedAttribute(object|string $classOrObject, string $attribute, ?string $format = null, array $context = [])
     {
         $ignoredAttributes = $context[self::IGNORED_ATTRIBUTES] ?? $this->defaultContext[self::IGNORED_ATTRIBUTES];
         if (\in_array($attribute, $ignoredAttributes)) {
@@ -321,7 +321,7 @@ protected function getConstructor(array &$data, string $class, array &$context,
      * @throws RuntimeException
      * @throws MissingConstructorArgumentsException
      */
-    protected function instantiateObject(array &$data, string $class, array &$context, \ReflectionClass $reflectionClass, array|bool $allowedAttributes, string $format = null)
+    protected function instantiateObject(array &$data, string $class, array &$context, \ReflectionClass $reflectionClass, array|bool $allowedAttributes, ?string $format = null)
     {
         if (null !== $object = $this->extractObjectToPopulate($class, $context, self::OBJECT_TO_POPULATE)) {
             unset($context[self::OBJECT_TO_POPULATE]);
@@ -361,7 +361,7 @@ protected function instantiateObject(array &$data, string $class, array &$contex
                             $variadicParameters[$parameterKey] = $this->denormalizeParameter($reflectionClass, $constructorParameter, $paramName, $parameterData, $attributeContext, $format);
                         }
 
-                        $params = array_merge($params, $variadicParameters);
+                        $params = array_merge(array_values($params), $variadicParameters);
                         $unsetKeys[] = $key;
                     }
                 } elseif ($allowed && !$ignored && (isset($data[$key]) || \array_key_exists($key, $data))) {
@@ -403,7 +403,7 @@ protected function instantiateObject(array &$data, string $class, array &$contex
                         sprintf('Failed to create object because the class misses the "%s" property.', $constructorParameter->name),
                         $data,
                         ['unknown'],
-                        $context['deserialization_path'] ?? null,
+                        $attributeContext['deserialization_path'] ?? null,
                         true
                     );
                     $context['not_normalizable_value_exceptions'][] = $exception;
@@ -460,7 +460,7 @@ protected function instantiateObject(array &$data, string $class, array &$contex
     /**
      * @internal
      */
-    protected function denormalizeParameter(\ReflectionClass $class, \ReflectionParameter $parameter, string $parameterName, mixed $parameterData, array $context, string $format = null): mixed
+    protected function denormalizeParameter(\ReflectionClass $class, \ReflectionParameter $parameter, string $parameterName, mixed $parameterData, array $context, ?string $format = null): mixed
     {
         try {
             if (($parameterType = $parameter->getType()) instanceof \ReflectionNamedType && !$parameterType->isBuiltin()) {
diff --git a/Normalizer/AbstractObjectNormalizer.php b/Normalizer/AbstractObjectNormalizer.php
index d43cbbbdd..11ba28c75 100644
--- a/Normalizer/AbstractObjectNormalizer.php
+++ b/Normalizer/AbstractObjectNormalizer.php
@@ -116,11 +116,11 @@ abstract class AbstractObjectNormalizer extends AbstractNormalizer
     protected $classDiscriminatorResolver;
 
     public function __construct(
-        ClassMetadataFactoryInterface $classMetadataFactory = null,
-        NameConverterInterface $nameConverter = null,
+        ?ClassMetadataFactoryInterface $classMetadataFactory = null,
+        ?NameConverterInterface $nameConverter = null,
         private ?PropertyTypeExtractorInterface $propertyTypeExtractor = null,
-        ClassDiscriminatorResolverInterface $classDiscriminatorResolver = null,
-        callable $objectClassResolver = null,
+        ?ClassDiscriminatorResolverInterface $classDiscriminatorResolver = null,
+        ?callable $objectClassResolver = null,
         array $defaultContext = [],
     ) {
         parent::__construct($classMetadataFactory, $nameConverter, $defaultContext);
@@ -143,7 +143,7 @@ public function __construct(
      *
      * @return bool
      */
-    public function supportsNormalization(mixed $data, string $format = null /* , array $context = [] */)
+    public function supportsNormalization(mixed $data, ?string $format = null /* , array $context = [] */)
     {
         return \is_object($data) && !$data instanceof \Traversable;
     }
@@ -151,7 +151,7 @@ public function supportsNormalization(mixed $data, string $format = null /* , ar
     /**
      * @return array|string|int|float|bool|\ArrayObject|null
      */
-    public function normalize(mixed $object, string $format = null, array $context = [])
+    public function normalize(mixed $object, ?string $format = null, array $context = [])
     {
         if (!isset($context['cache_key'])) {
             $context['cache_key'] = $this->getCacheKey($format, $context);
@@ -232,7 +232,7 @@ public function normalize(mixed $object, string $format = null, array $context =
     /**
      * @return object
      */
-    protected function instantiateObject(array &$data, string $class, array &$context, \ReflectionClass $reflectionClass, array|bool $allowedAttributes, string $format = null)
+    protected function instantiateObject(array &$data, string $class, array &$context, \ReflectionClass $reflectionClass, array|bool $allowedAttributes, ?string $format = null)
     {
         if ($class !== $mappedClass = $this->getMappedClass($data, $class, $context)) {
             return $this->instantiateObject($data, $mappedClass, $context, new \ReflectionClass($mappedClass), $allowedAttributes, $format);
@@ -283,21 +283,21 @@ protected function getAttributes(object $object, ?string $format, array $context
      *
      * @return string[]
      */
-    abstract protected function extractAttributes(object $object, string $format = null, array $context = []);
+    abstract protected function extractAttributes(object $object, ?string $format = null, array $context = []);
 
     /**
      * Gets the attribute value.
      *
      * @return mixed
      */
-    abstract protected function getAttributeValue(object $object, string $attribute, string $format = null, array $context = []);
+    abstract protected function getAttributeValue(object $object, string $attribute, ?string $format = null, array $context = []);
 
     /**
      * @param array $context
      *
      * @return bool
      */
-    public function supportsDenormalization(mixed $data, string $type, string $format = null /* , array $context = [] */)
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null /* , array $context = [] */)
     {
         return class_exists($type) || (interface_exists($type, false) && null !== $this->classDiscriminatorResolver?->getMappingForClass($type));
     }
@@ -305,7 +305,7 @@ public function supportsDenormalization(mixed $data, string $type, string $forma
     /**
      * @return mixed
      */
-    public function denormalize(mixed $data, string $type, string $format = null, array $context = [])
+    public function denormalize(mixed $data, string $type, ?string $format = null, array $context = [])
     {
         if (!isset($context['cache_key'])) {
             $context['cache_key'] = $this->getCacheKey($format, $context);
@@ -398,7 +398,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
                     sprintf('Failed to denormalize attribute "%s" value for class "%s": '.$e->getMessage(), $attribute, $type),
                     $data,
                     ['unknown'],
-                    $context['deserialization_path'] ?? null,
+                    $attributeContext['deserialization_path'] ?? null,
                     false,
                     $e->getCode(),
                     $e
@@ -421,7 +421,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
     /**
      * @return void
      */
-    abstract protected function setAttributeValue(object $object, string $attribute, mixed $value, string $format = null, array $context = []);
+    abstract protected function setAttributeValue(object $object, string $attribute, mixed $value, ?string $format = null, array $context = []);
 
     /**
      * Validates the submitted data and denormalizes it.
@@ -619,7 +619,7 @@ private function validateAndDenormalize(array $types, string $currentClass, stri
     /**
      * @internal
      */
-    protected function denormalizeParameter(\ReflectionClass $class, \ReflectionParameter $parameter, string $parameterName, mixed $parameterData, array $context, string $format = null): mixed
+    protected function denormalizeParameter(\ReflectionClass $class, \ReflectionParameter $parameter, string $parameterName, mixed $parameterData, array $context, ?string $format = null): mixed
     {
         if ($parameter->isVariadic() || null === $this->propertyTypeExtractor || null === $types = $this->getTypes($class->getName(), $parameterName)) {
             return parent::denormalizeParameter($class, $parameter, $parameterName, $parameterData, $context, $format);
@@ -734,7 +734,11 @@ private function isMaxDepthReached(array $attributesMetadata, string $class, str
     protected function createChildContext(array $parentContext, string $attribute, ?string $format): array
     {
         $context = parent::createChildContext($parentContext, $attribute, $format);
-        $context['cache_key'] = $this->getCacheKey($format, $context);
+        if ($context['cache_key'] ?? false) {
+            $context['cache_key'] .= '-'.$attribute;
+        } elseif (false !== ($context['cache_key'] ?? null)) {
+            $context['cache_key'] = $this->getCacheKey($format, $context);
+        }
 
         return $context;
     }
diff --git a/Normalizer/ArrayDenormalizer.php b/Normalizer/ArrayDenormalizer.php
index e6669634a..38aee6d86 100644
--- a/Normalizer/ArrayDenormalizer.php
+++ b/Normalizer/ArrayDenormalizer.php
@@ -44,7 +44,7 @@ public function getSupportedTypes(?string $format): array
     /**
      * @throws NotNormalizableValueException
      */
-    public function denormalize(mixed $data, string $type, string $format = null, array $context = []): array
+    public function denormalize(mixed $data, string $type, ?string $format = null, array $context = []): array
     {
         if (null === $this->denormalizer) {
             throw new BadMethodCallException('Please set a denormalizer before calling denormalize()!');
@@ -74,7 +74,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
         return $data;
     }
 
-    public function supportsDenormalization(mixed $data, string $type, string $format = null, array $context = []): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null, array $context = []): bool
     {
         if (null === $this->denormalizer) {
             throw new BadMethodCallException(sprintf('The nested denormalizer needs to be set to allow "%s()" to be used.', __METHOD__));
diff --git a/Normalizer/BackedEnumNormalizer.php b/Normalizer/BackedEnumNormalizer.php
index fc7a70188..8b0aa7f5a 100644
--- a/Normalizer/BackedEnumNormalizer.php
+++ b/Normalizer/BackedEnumNormalizer.php
@@ -34,7 +34,7 @@ public function getSupportedTypes(?string $format): array
         ];
     }
 
-    public function normalize(mixed $object, string $format = null, array $context = []): int|string
+    public function normalize(mixed $object, ?string $format = null, array $context = []): int|string
     {
         if (!$object instanceof \BackedEnum) {
             throw new InvalidArgumentException('The data must belong to a backed enumeration.');
@@ -43,7 +43,7 @@ public function normalize(mixed $object, string $format = null, array $context =
         return $object->value;
     }
 
-    public function supportsNormalization(mixed $data, string $format = null, array $context = []): bool
+    public function supportsNormalization(mixed $data, ?string $format = null, array $context = []): bool
     {
         return $data instanceof \BackedEnum;
     }
@@ -51,7 +51,7 @@ public function supportsNormalization(mixed $data, string $format = null, array
     /**
      * @throws NotNormalizableValueException
      */
-    public function denormalize(mixed $data, string $type, string $format = null, array $context = []): mixed
+    public function denormalize(mixed $data, string $type, ?string $format = null, array $context = []): mixed
     {
         if (!is_subclass_of($type, \BackedEnum::class)) {
             throw new InvalidArgumentException('The data must belong to a backed enumeration.');
@@ -84,7 +84,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
         }
     }
 
-    public function supportsDenormalization(mixed $data, string $type, string $format = null, array $context = []): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null, array $context = []): bool
     {
         return is_subclass_of($type, \BackedEnum::class);
     }
diff --git a/Normalizer/ConstraintViolationListNormalizer.php b/Normalizer/ConstraintViolationListNormalizer.php
index 2b6a8ec2e..814b6f872 100644
--- a/Normalizer/ConstraintViolationListNormalizer.php
+++ b/Normalizer/ConstraintViolationListNormalizer.php
@@ -45,7 +45,7 @@ public function getSupportedTypes(?string $format): array
         ];
     }
 
-    public function normalize(mixed $object, string $format = null, array $context = []): array
+    public function normalize(mixed $object, ?string $format = null, array $context = []): array
     {
         if (\array_key_exists(self::PAYLOAD_FIELDS, $context)) {
             $payloadFieldsToSerialize = $context[self::PAYLOAD_FIELDS];
@@ -111,7 +111,7 @@ public function normalize(mixed $object, string $format = null, array $context =
     /**
      * @param array $context
      */
-    public function supportsNormalization(mixed $data, string $format = null /* , array $context = [] */): bool
+    public function supportsNormalization(mixed $data, ?string $format = null /* , array $context = [] */): bool
     {
         return $data instanceof ConstraintViolationListInterface;
     }
diff --git a/Normalizer/ContextAwareDenormalizerInterface.php b/Normalizer/ContextAwareDenormalizerInterface.php
index a02951093..19fe3ad1f 100644
--- a/Normalizer/ContextAwareDenormalizerInterface.php
+++ b/Normalizer/ContextAwareDenormalizerInterface.php
@@ -23,5 +23,5 @@ interface ContextAwareDenormalizerInterface extends DenormalizerInterface
     /**
      * @param array $context options that denormalizers have access to
      */
-    public function supportsDenormalization(mixed $data, string $type, string $format = null, array $context = []): bool;
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null, array $context = []): bool;
 }
diff --git a/Normalizer/ContextAwareNormalizerInterface.php b/Normalizer/ContextAwareNormalizerInterface.php
index 44f2f0219..164d638e5 100644
--- a/Normalizer/ContextAwareNormalizerInterface.php
+++ b/Normalizer/ContextAwareNormalizerInterface.php
@@ -23,5 +23,5 @@ interface ContextAwareNormalizerInterface extends NormalizerInterface
     /**
      * @param array $context options that normalizers have access to
      */
-    public function supportsNormalization(mixed $data, string $format = null, array $context = []): bool;
+    public function supportsNormalization(mixed $data, ?string $format = null, array $context = []): bool;
 }
diff --git a/Normalizer/CustomNormalizer.php b/Normalizer/CustomNormalizer.php
index f45f36296..d7f61b4d4 100644
--- a/Normalizer/CustomNormalizer.php
+++ b/Normalizer/CustomNormalizer.php
@@ -32,12 +32,12 @@ public function getSupportedTypes(?string $format): array
         ];
     }
 
-    public function normalize(mixed $object, string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
+    public function normalize(mixed $object, ?string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
     {
         return $object->normalize($this->serializer, $format, $context);
     }
 
-    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
     {
         $object = $this->extractObjectToPopulate($type, $context) ?? new $type();
         $object->denormalize($this->serializer, $data, $format, $context);
@@ -52,7 +52,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
      * @param string|null $format The format being (de-)serialized from or into
      * @param array       $context
      */
-    public function supportsNormalization(mixed $data, string $format = null /* , array $context = [] */): bool
+    public function supportsNormalization(mixed $data, ?string $format = null /* , array $context = [] */): bool
     {
         return $data instanceof NormalizableInterface;
     }
@@ -65,7 +65,7 @@ public function supportsNormalization(mixed $data, string $format = null /* , ar
      * @param string|null $format The format being deserialized from
      * @param array       $context
      */
-    public function supportsDenormalization(mixed $data, string $type, string $format = null /* , array $context = [] */): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null /* , array $context = [] */): bool
     {
         return is_subclass_of($type, DenormalizableInterface::class);
     }
diff --git a/Normalizer/DataUriNormalizer.php b/Normalizer/DataUriNormalizer.php
index 0b4d0b273..9252a69b5 100644
--- a/Normalizer/DataUriNormalizer.php
+++ b/Normalizer/DataUriNormalizer.php
@@ -35,7 +35,7 @@ class DataUriNormalizer implements NormalizerInterface, DenormalizerInterface, C
 
     private readonly ?MimeTypeGuesserInterface $mimeTypeGuesser;
 
-    public function __construct(MimeTypeGuesserInterface $mimeTypeGuesser = null)
+    public function __construct(?MimeTypeGuesserInterface $mimeTypeGuesser = null)
     {
         if (!$mimeTypeGuesser && class_exists(MimeTypes::class)) {
             $mimeTypeGuesser = MimeTypes::getDefault();
@@ -55,7 +55,7 @@ public function getSupportedTypes(?string $format): array
         ];
     }
 
-    public function normalize(mixed $object, string $format = null, array $context = []): string
+    public function normalize(mixed $object, ?string $format = null, array $context = []): string
     {
         if (!$object instanceof \SplFileInfo) {
             throw new InvalidArgumentException('The object must be an instance of "\SplFileInfo".');
@@ -81,7 +81,7 @@ public function normalize(mixed $object, string $format = null, array $context =
     /**
      * @param array $context
      */
-    public function supportsNormalization(mixed $data, string $format = null /* , array $context = [] */): bool
+    public function supportsNormalization(mixed $data, ?string $format = null /* , array $context = [] */): bool
     {
         return $data instanceof \SplFileInfo;
     }
@@ -94,7 +94,7 @@ public function supportsNormalization(mixed $data, string $format = null /* , ar
      * @throws InvalidArgumentException
      * @throws NotNormalizableValueException
      */
-    public function denormalize(mixed $data, string $type, string $format = null, array $context = []): \SplFileInfo
+    public function denormalize(mixed $data, string $type, ?string $format = null, array $context = []): \SplFileInfo
     {
         if (null === $data || !preg_match('/^data:([a-z0-9][a-z0-9\!\#\$\&\-\^\_\+\.]{0,126}\/[a-z0-9][a-z0-9\!\#\$\&\-\^\_\+\.]{0,126}(;[a-z0-9\-]+\=[a-z0-9\-]+)?)?(;base64)?,[a-z0-9\!\$\&\\\'\,\(\)\*\+\,\;\=\-\.\_\~\:\@\/\?\%\s]*\s*$/i', $data)) {
             throw NotNormalizableValueException::createForUnexpectedDataType('The provided "data:" URI is not valid.', $data, ['string'], $context['deserialization_path'] ?? null, true);
@@ -123,7 +123,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
     /**
      * @param array $context
      */
-    public function supportsDenormalization(mixed $data, string $type, string $format = null /* , array $context = [] */): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null /* , array $context = [] */): bool
     {
         return isset(self::SUPPORTED_TYPES[$type]);
     }
diff --git a/Normalizer/DateIntervalNormalizer.php b/Normalizer/DateIntervalNormalizer.php
index 202f0e861..ce59a71a9 100644
--- a/Normalizer/DateIntervalNormalizer.php
+++ b/Normalizer/DateIntervalNormalizer.php
@@ -45,7 +45,7 @@ public function getSupportedTypes(?string $format): array
     /**
      * @throws InvalidArgumentException
      */
-    public function normalize(mixed $object, string $format = null, array $context = []): string
+    public function normalize(mixed $object, ?string $format = null, array $context = []): string
     {
         if (!$object instanceof \DateInterval) {
             throw new InvalidArgumentException('The object must be an instance of "\DateInterval".');
@@ -57,7 +57,7 @@ public function normalize(mixed $object, string $format = null, array $context =
     /**
      * @param array $context
      */
-    public function supportsNormalization(mixed $data, string $format = null /* , array $context = [] */): bool
+    public function supportsNormalization(mixed $data, ?string $format = null /* , array $context = [] */): bool
     {
         return $data instanceof \DateInterval;
     }
@@ -75,7 +75,7 @@ public function hasCacheableSupportsMethod(): bool
     /**
      * @throws NotNormalizableValueException
      */
-    public function denormalize(mixed $data, string $type, string $format = null, array $context = []): \DateInterval
+    public function denormalize(mixed $data, string $type, ?string $format = null, array $context = []): \DateInterval
     {
         if (!\is_string($data)) {
             throw NotNormalizableValueException::createForUnexpectedDataType('Data expected to be a string.', $data, ['string'], $context['deserialization_path'] ?? null, true);
@@ -124,7 +124,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
     /**
      * @param array $context
      */
-    public function supportsDenormalization(mixed $data, string $type, string $format = null /* , array $context = [] */): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null /* , array $context = [] */): bool
     {
         return \DateInterval::class === $type;
     }
diff --git a/Normalizer/DateTimeNormalizer.php b/Normalizer/DateTimeNormalizer.php
index 37fa2ef42..82d2657c5 100644
--- a/Normalizer/DateTimeNormalizer.php
+++ b/Normalizer/DateTimeNormalizer.php
@@ -63,7 +63,7 @@ public function getSupportedTypes(?string $format): array
     /**
      * @throws InvalidArgumentException
      */
-    public function normalize(mixed $object, string $format = null, array $context = []): string
+    public function normalize(mixed $object, ?string $format = null, array $context = []): string
     {
         if (!$object instanceof \DateTimeInterface) {
             throw new InvalidArgumentException('The object must implement the "\DateTimeInterface".');
@@ -83,7 +83,7 @@ public function normalize(mixed $object, string $format = null, array $context =
     /**
      * @param array $context
      */
-    public function supportsNormalization(mixed $data, string $format = null /* , array $context = [] */): bool
+    public function supportsNormalization(mixed $data, ?string $format = null /* , array $context = [] */): bool
     {
         return $data instanceof \DateTimeInterface;
     }
@@ -91,7 +91,7 @@ public function supportsNormalization(mixed $data, string $format = null /* , ar
     /**
      * @throws NotNormalizableValueException
      */
-    public function denormalize(mixed $data, string $type, string $format = null, array $context = []): \DateTimeInterface
+    public function denormalize(mixed $data, string $type, ?string $format = null, array $context = []): \DateTimeInterface
     {
         if (\is_int($data) || \is_float($data)) {
             switch ($context[self::FORMAT_KEY] ?? $this->defaultContext[self::FORMAT_KEY] ?? null) {
@@ -141,7 +141,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
     /**
      * @param array $context
      */
-    public function supportsDenormalization(mixed $data, string $type, string $format = null /* , array $context = [] */): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null /* , array $context = [] */): bool
     {
         return isset(self::SUPPORTED_TYPES[$type]);
     }
diff --git a/Normalizer/DateTimeZoneNormalizer.php b/Normalizer/DateTimeZoneNormalizer.php
index b4e1584ad..892a576ce 100644
--- a/Normalizer/DateTimeZoneNormalizer.php
+++ b/Normalizer/DateTimeZoneNormalizer.php
@@ -34,7 +34,7 @@ public function getSupportedTypes(?string $format): array
     /**
      * @throws InvalidArgumentException
      */
-    public function normalize(mixed $object, string $format = null, array $context = []): string
+    public function normalize(mixed $object, ?string $format = null, array $context = []): string
     {
         if (!$object instanceof \DateTimeZone) {
             throw new InvalidArgumentException('The object must be an instance of "\DateTimeZone".');
@@ -46,7 +46,7 @@ public function normalize(mixed $object, string $format = null, array $context =
     /**
      * @param array $context
      */
-    public function supportsNormalization(mixed $data, string $format = null /* , array $context = [] */): bool
+    public function supportsNormalization(mixed $data, ?string $format = null /* , array $context = [] */): bool
     {
         return $data instanceof \DateTimeZone;
     }
@@ -54,7 +54,7 @@ public function supportsNormalization(mixed $data, string $format = null /* , ar
     /**
      * @throws NotNormalizableValueException
      */
-    public function denormalize(mixed $data, string $type, string $format = null, array $context = []): \DateTimeZone
+    public function denormalize(mixed $data, string $type, ?string $format = null, array $context = []): \DateTimeZone
     {
         if ('' === $data || null === $data) {
             throw NotNormalizableValueException::createForUnexpectedDataType('The data is either an empty string or null, you should pass a string that can be parsed as a DateTimeZone.', $data, [Type::BUILTIN_TYPE_STRING], $context['deserialization_path'] ?? null, true);
@@ -70,7 +70,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
     /**
      * @param array $context
      */
-    public function supportsDenormalization(mixed $data, string $type, string $format = null /* , array $context = [] */): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null /* , array $context = [] */): bool
     {
         return \DateTimeZone::class === $type;
     }
diff --git a/Normalizer/DenormalizableInterface.php b/Normalizer/DenormalizableInterface.php
index 503f3cb51..1811c93a4 100644
--- a/Normalizer/DenormalizableInterface.php
+++ b/Normalizer/DenormalizableInterface.php
@@ -36,5 +36,5 @@ interface DenormalizableInterface
      *
      * @return void
      */
-    public function denormalize(DenormalizerInterface $denormalizer, array|string|int|float|bool $data, string $format = null, array $context = []);
+    public function denormalize(DenormalizerInterface $denormalizer, array|string|int|float|bool $data, ?string $format = null, array $context = []);
 }
diff --git a/Normalizer/DenormalizerInterface.php b/Normalizer/DenormalizerInterface.php
index d047ec298..98c59fc66 100644
--- a/Normalizer/DenormalizerInterface.php
+++ b/Normalizer/DenormalizerInterface.php
@@ -46,7 +46,7 @@ interface DenormalizerInterface
      * @throws RuntimeException         Occurs if the class cannot be instantiated
      * @throws ExceptionInterface       Occurs for all the other cases of errors
      */
-    public function denormalize(mixed $data, string $type, string $format = null, array $context = []);
+    public function denormalize(mixed $data, string $type, ?string $format = null, array $context = []);
 
     /**
      * Checks whether the given class is supported for denormalization by this normalizer.
@@ -58,7 +58,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
      *
      * @return bool
      */
-    public function supportsDenormalization(mixed $data, string $type, string $format = null /* , array $context = [] */);
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null /* , array $context = [] */);
 
     /**
      * Returns the types potentially supported by this denormalizer.
diff --git a/Normalizer/FormErrorNormalizer.php b/Normalizer/FormErrorNormalizer.php
index 57d9bd4bb..8c0d3a1c0 100644
--- a/Normalizer/FormErrorNormalizer.php
+++ b/Normalizer/FormErrorNormalizer.php
@@ -22,7 +22,7 @@ final class FormErrorNormalizer implements NormalizerInterface, CacheableSupport
     public const TYPE = 'type';
     public const CODE = 'status_code';
 
-    public function normalize(mixed $object, string $format = null, array $context = []): array
+    public function normalize(mixed $object, ?string $format = null, array $context = []): array
     {
         $data = [
             'title' => $context[self::TITLE] ?? 'Validation Failed',
@@ -45,7 +45,7 @@ public function getSupportedTypes(?string $format): array
         ];
     }
 
-    public function supportsNormalization(mixed $data, string $format = null, array $context = []): bool
+    public function supportsNormalization(mixed $data, ?string $format = null, array $context = []): bool
     {
         return $data instanceof FormInterface && $data->isSubmitted() && !$data->isValid();
     }
diff --git a/Normalizer/GetSetMethodNormalizer.php b/Normalizer/GetSetMethodNormalizer.php
index b47ea6a5f..b4e2bef56 100644
--- a/Normalizer/GetSetMethodNormalizer.php
+++ b/Normalizer/GetSetMethodNormalizer.php
@@ -48,7 +48,7 @@ public function getSupportedTypes(?string $format): array
     /**
      * @param array $context
      */
-    public function supportsNormalization(mixed $data, string $format = null /* , array $context = [] */): bool
+    public function supportsNormalization(mixed $data, ?string $format = null /* , array $context = [] */): bool
     {
         return parent::supportsNormalization($data, $format) && $this->supports($data::class);
     }
@@ -56,7 +56,7 @@ public function supportsNormalization(mixed $data, string $format = null /* , ar
     /**
      * @param array $context
      */
-    public function supportsDenormalization(mixed $data, string $type, string $format = null /* , array $context = [] */): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null /* , array $context = [] */): bool
     {
         return parent::supportsDenormalization($data, $type, $format) && $this->supports($type);
     }
@@ -104,7 +104,7 @@ private function isGetMethod(\ReflectionMethod $method): bool
             );
     }
 
-    protected function extractAttributes(object $object, string $format = null, array $context = []): array
+    protected function extractAttributes(object $object, ?string $format = null, array $context = []): array
     {
         $reflectionObject = new \ReflectionObject($object);
         $reflectionMethods = $reflectionObject->getMethods(\ReflectionMethod::IS_PUBLIC);
@@ -125,7 +125,7 @@ protected function extractAttributes(object $object, string $format = null, arra
         return $attributes;
     }
 
-    protected function getAttributeValue(object $object, string $attribute, string $format = null, array $context = []): mixed
+    protected function getAttributeValue(object $object, string $attribute, ?string $format = null, array $context = []): mixed
     {
         $ucfirsted = ucfirst($attribute);
 
@@ -150,7 +150,7 @@ protected function getAttributeValue(object $object, string $attribute, string $
     /**
      * @return void
      */
-    protected function setAttributeValue(object $object, string $attribute, mixed $value, string $format = null, array $context = [])
+    protected function setAttributeValue(object $object, string $attribute, mixed $value, ?string $format = null, array $context = [])
     {
         $setter = 'set'.ucfirst($attribute);
         $key = $object::class.':'.$setter;
diff --git a/Normalizer/JsonSerializableNormalizer.php b/Normalizer/JsonSerializableNormalizer.php
index 238cffa1e..0753c8ba7 100644
--- a/Normalizer/JsonSerializableNormalizer.php
+++ b/Normalizer/JsonSerializableNormalizer.php
@@ -23,7 +23,7 @@
  */
 class JsonSerializableNormalizer extends AbstractNormalizer
 {
-    public function normalize(mixed $object, string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
+    public function normalize(mixed $object, ?string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
     {
         if ($this->isCircularReference($object, $context)) {
             return $this->handleCircularReference($object, $format, $context);
@@ -50,7 +50,7 @@ public function getSupportedTypes(?string $format): array
     /**
      * @param array $context
      */
-    public function supportsNormalization(mixed $data, string $format = null /* , array $context = [] */): bool
+    public function supportsNormalization(mixed $data, ?string $format = null /* , array $context = [] */): bool
     {
         return $data instanceof \JsonSerializable;
     }
@@ -58,12 +58,12 @@ public function supportsNormalization(mixed $data, string $format = null /* , ar
     /**
      * @param array $context
      */
-    public function supportsDenormalization(mixed $data, string $type, string $format = null /* , array $context = [] */): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null /* , array $context = [] */): bool
     {
         return false;
     }
 
-    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
     {
         throw new LogicException(sprintf('Cannot denormalize with "%s".', \JsonSerializable::class));
     }
diff --git a/Normalizer/MimeMessageNormalizer.php b/Normalizer/MimeMessageNormalizer.php
index ab9544bf2..07a170d6b 100644
--- a/Normalizer/MimeMessageNormalizer.php
+++ b/Normalizer/MimeMessageNormalizer.php
@@ -17,6 +17,7 @@
 use Symfony\Component\Mime\Header\UnstructuredHeader;
 use Symfony\Component\Mime\Message;
 use Symfony\Component\Mime\Part\AbstractPart;
+use Symfony\Component\Mime\RawMessage;
 use Symfony\Component\Serializer\Exception\LogicException;
 use Symfony\Component\Serializer\SerializerAwareInterface;
 use Symfony\Component\Serializer\SerializerInterface;
@@ -63,7 +64,7 @@ public function setSerializer(SerializerInterface $serializer): void
         $this->normalizer->setSerializer($serializer);
     }
 
-    public function normalize(mixed $object, string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
+    public function normalize(mixed $object, ?string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
     {
         if ($object instanceof Headers) {
             $ret = [];
@@ -74,18 +75,21 @@ public function normalize(mixed $object, string $format = null, array $context =
             return $ret;
         }
 
+        $ret = $this->normalizer->normalize($object, $format, $context);
+
         if ($object instanceof AbstractPart) {
-            $ret = $this->normalizer->normalize($object, $format, $context);
             $ret['class'] = $object::class;
             unset($ret['seekable'], $ret['cid'], $ret['handle']);
+        }
 
-            return $ret;
+        if ($object instanceof RawMessage && \array_key_exists('message', $ret) && null === $ret['message']) {
+            unset($ret['message']);
         }
 
-        return $this->normalizer->normalize($object, $format, $context);
+        return $ret;
     }
 
-    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 (Headers::class === $type) {
             $ret = [];
@@ -107,12 +111,12 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
         return $this->normalizer->denormalize($data, $type, $format, $context);
     }
 
-    public function supportsNormalization(mixed $data, string $format = null, array $context = []): bool
+    public function supportsNormalization(mixed $data, ?string $format = null, array $context = []): bool
     {
         return $data instanceof Message || $data instanceof Headers || $data instanceof HeaderInterface || $data instanceof Address || $data instanceof AbstractPart;
     }
 
-    public function supportsDenormalization(mixed $data, string $type, string $format = null, array $context = []): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null, array $context = []): bool
     {
         return is_a($type, Message::class, true) || Headers::class === $type || AbstractPart::class === $type;
     }
diff --git a/Normalizer/NormalizableInterface.php b/Normalizer/NormalizableInterface.php
index 0bad9d183..7be598668 100644
--- a/Normalizer/NormalizableInterface.php
+++ b/Normalizer/NormalizableInterface.php
@@ -33,5 +33,5 @@ interface NormalizableInterface
      *                                        based on different output formats
      * @param array               $context    Options for normalizing this object
      */
-    public function normalize(NormalizerInterface $normalizer, string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null;
+    public function normalize(NormalizerInterface $normalizer, ?string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null;
 }
diff --git a/Normalizer/NormalizerInterface.php b/Normalizer/NormalizerInterface.php
index 5710167f4..4bf04602e 100644
--- a/Normalizer/NormalizerInterface.php
+++ b/Normalizer/NormalizerInterface.php
@@ -38,7 +38,7 @@ interface NormalizerInterface
      * @throws LogicException             Occurs when the normalizer is not called in an expected context
      * @throws ExceptionInterface         Occurs for all the other cases of errors
      */
-    public function normalize(mixed $object, string $format = null, array $context = []);
+    public function normalize(mixed $object, ?string $format = null, array $context = []);
 
     /**
      * Checks whether the given class is supported for normalization by this normalizer.
@@ -49,7 +49,7 @@ public function normalize(mixed $object, string $format = null, array $context =
      *
      * @return bool
      */
-    public function supportsNormalization(mixed $data, string $format = null /* , array $context = [] */);
+    public function supportsNormalization(mixed $data, ?string $format = null /* , array $context = [] */);
 
     /**
      * Returns the types potentially supported by this normalizer.
diff --git a/Normalizer/ObjectNormalizer.php b/Normalizer/ObjectNormalizer.php
index 3f4638ca6..eb37f8897 100644
--- a/Normalizer/ObjectNormalizer.php
+++ b/Normalizer/ObjectNormalizer.php
@@ -34,7 +34,7 @@ class ObjectNormalizer extends AbstractObjectNormalizer
 
     private readonly \Closure $objectClassResolver;
 
-    public function __construct(ClassMetadataFactoryInterface $classMetadataFactory = null, NameConverterInterface $nameConverter = null, PropertyAccessorInterface $propertyAccessor = null, PropertyTypeExtractorInterface $propertyTypeExtractor = null, ClassDiscriminatorResolverInterface $classDiscriminatorResolver = null, callable $objectClassResolver = null, array $defaultContext = [])
+    public function __construct(?ClassMetadataFactoryInterface $classMetadataFactory = null, ?NameConverterInterface $nameConverter = null, ?PropertyAccessorInterface $propertyAccessor = null, ?PropertyTypeExtractorInterface $propertyTypeExtractor = null, ?ClassDiscriminatorResolverInterface $classDiscriminatorResolver = null, ?callable $objectClassResolver = null, array $defaultContext = [])
     {
         if (!class_exists(PropertyAccess::class)) {
             throw new LogicException('The ObjectNormalizer class requires the "PropertyAccess" component. Install "symfony/property-access" to use it.');
@@ -62,7 +62,7 @@ public function hasCacheableSupportsMethod(): bool
         return __CLASS__ === static::class;
     }
 
-    protected function extractAttributes(object $object, string $format = null, array $context = []): array
+    protected function extractAttributes(object $object, ?string $format = null, array $context = []): array
     {
         if (\stdClass::class === $object::class) {
             return array_keys((array) $object);
@@ -125,7 +125,7 @@ protected function extractAttributes(object $object, string $format = null, arra
         return array_keys($attributes);
     }
 
-    protected function getAttributeValue(object $object, string $attribute, string $format = null, array $context = []): mixed
+    protected function getAttributeValue(object $object, string $attribute, ?string $format = null, array $context = []): mixed
     {
         $mapping = $this->classDiscriminatorResolver?->getMappingForMappedObject($object);
 
@@ -137,7 +137,7 @@ protected function getAttributeValue(object $object, string $attribute, string $
     /**
      * @return void
      */
-    protected function setAttributeValue(object $object, string $attribute, mixed $value, string $format = null, array $context = [])
+    protected function setAttributeValue(object $object, string $attribute, mixed $value, ?string $format = null, array $context = [])
     {
         try {
             $this->propertyAccessor->setValue($object, $attribute, $value);
diff --git a/Normalizer/ObjectToPopulateTrait.php b/Normalizer/ObjectToPopulateTrait.php
index 23be4c6af..21ad5f7ad 100644
--- a/Normalizer/ObjectToPopulateTrait.php
+++ b/Normalizer/ObjectToPopulateTrait.php
@@ -21,7 +21,7 @@ trait ObjectToPopulateTrait
      * @param string|null $key   They in which to look for the object to populate.
      *                           Keeps backwards compatibility with `AbstractNormalizer`.
      */
-    protected function extractObjectToPopulate(string $class, array $context, string $key = null): ?object
+    protected function extractObjectToPopulate(string $class, array $context, ?string $key = null): ?object
     {
         $key ??= AbstractNormalizer::OBJECT_TO_POPULATE;
 
diff --git a/Normalizer/ProblemNormalizer.php b/Normalizer/ProblemNormalizer.php
index f7a8077ec..66e2d0647 100644
--- a/Normalizer/ProblemNormalizer.php
+++ b/Normalizer/ProblemNormalizer.php
@@ -50,7 +50,7 @@ public function getSupportedTypes(?string $format): array
         ];
     }
 
-    public function normalize(mixed $object, string $format = null, array $context = []): array
+    public function normalize(mixed $object, ?string $format = null, array $context = []): array
     {
         if (!$object instanceof FlattenException) {
             throw new InvalidArgumentException(sprintf('The object must implement "%s".', FlattenException::class));
@@ -109,7 +109,7 @@ public function normalize(mixed $object, string $format = null, array $context =
     /**
      * @param array $context
      */
-    public function supportsNormalization(mixed $data, string $format = null /* , array $context = [] */): bool
+    public function supportsNormalization(mixed $data, ?string $format = null /* , array $context = [] */): bool
     {
         return $data instanceof FlattenException;
     }
diff --git a/Normalizer/PropertyNormalizer.php b/Normalizer/PropertyNormalizer.php
index 7b3a26426..6a5d0acd8 100644
--- a/Normalizer/PropertyNormalizer.php
+++ b/Normalizer/PropertyNormalizer.php
@@ -47,7 +47,7 @@ class PropertyNormalizer extends AbstractObjectNormalizer
      */
     public const NORMALIZE_VISIBILITY = 'normalize_visibility';
 
-    public function __construct(ClassMetadataFactoryInterface $classMetadataFactory = null, NameConverterInterface $nameConverter = null, PropertyTypeExtractorInterface $propertyTypeExtractor = null, ClassDiscriminatorResolverInterface $classDiscriminatorResolver = null, callable $objectClassResolver = null, array $defaultContext = [])
+    public function __construct(?ClassMetadataFactoryInterface $classMetadataFactory = null, ?NameConverterInterface $nameConverter = null, ?PropertyTypeExtractorInterface $propertyTypeExtractor = null, ?ClassDiscriminatorResolverInterface $classDiscriminatorResolver = null, ?callable $objectClassResolver = null, array $defaultContext = [])
     {
         parent::__construct($classMetadataFactory, $nameConverter, $propertyTypeExtractor, $classDiscriminatorResolver, $objectClassResolver, $defaultContext);
 
@@ -64,7 +64,7 @@ public function getSupportedTypes(?string $format): array
     /**
      * @param array $context
      */
-    public function supportsNormalization(mixed $data, string $format = null /* , array $context = [] */): bool
+    public function supportsNormalization(mixed $data, ?string $format = null /* , array $context = [] */): bool
     {
         return parent::supportsNormalization($data, $format) && $this->supports($data::class);
     }
@@ -72,7 +72,7 @@ public function supportsNormalization(mixed $data, string $format = null /* , ar
     /**
      * @param array $context
      */
-    public function supportsDenormalization(mixed $data, string $type, string $format = null /* , array $context = [] */): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null /* , array $context = [] */): bool
     {
         return parent::supportsDenormalization($data, $type, $format) && $this->supports($type);
     }
@@ -110,7 +110,7 @@ private function supports(string $class): bool
         return false;
     }
 
-    protected function isAllowedAttribute(object|string $classOrObject, string $attribute, string $format = null, array $context = []): bool
+    protected function isAllowedAttribute(object|string $classOrObject, string $attribute, ?string $format = null, array $context = []): bool
     {
         if (!parent::isAllowedAttribute($classOrObject, $attribute, $format, $context)) {
             return false;
@@ -143,7 +143,7 @@ protected function isAllowedAttribute(object|string $classOrObject, string $attr
         return false;
     }
 
-    protected function extractAttributes(object $object, string $format = null, array $context = []): array
+    protected function extractAttributes(object $object, ?string $format = null, array $context = []): array
     {
         $reflectionObject = new \ReflectionObject($object);
         $attributes = [];
@@ -161,7 +161,7 @@ protected function extractAttributes(object $object, string $format = null, arra
         return array_unique($attributes);
     }
 
-    protected function getAttributeValue(object $object, string $attribute, string $format = null, array $context = []): mixed
+    protected function getAttributeValue(object $object, string $attribute, ?string $format = null, array $context = []): mixed
     {
         try {
             $reflectionProperty = $this->getReflectionProperty($object, $attribute);
@@ -190,7 +190,7 @@ protected function getAttributeValue(object $object, string $attribute, string $
     /**
      * @return void
      */
-    protected function setAttributeValue(object $object, string $attribute, mixed $value, string $format = null, array $context = [])
+    protected function setAttributeValue(object $object, string $attribute, mixed $value, ?string $format = null, array $context = [])
     {
         try {
             $reflectionProperty = $this->getReflectionProperty($object, $attribute);
diff --git a/Normalizer/UidNormalizer.php b/Normalizer/UidNormalizer.php
index 0dfeae7b8..a5f8b8c0d 100644
--- a/Normalizer/UidNormalizer.php
+++ b/Normalizer/UidNormalizer.php
@@ -51,7 +51,7 @@ public function getSupportedTypes(?string $format): array
     /**
      * @param AbstractUid $object
      */
-    public function normalize(mixed $object, string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
+    public function normalize(mixed $object, ?string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
     {
         return match ($context[self::NORMALIZATION_FORMAT_KEY] ?? $this->defaultContext[self::NORMALIZATION_FORMAT_KEY]) {
             self::NORMALIZATION_FORMAT_CANONICAL => (string) $object,
@@ -62,12 +62,12 @@ public function normalize(mixed $object, string $format = null, array $context =
         };
     }
 
-    public function supportsNormalization(mixed $data, string $format = null, array $context = []): bool
+    public function supportsNormalization(mixed $data, ?string $format = null, array $context = []): bool
     {
         return $data instanceof AbstractUid;
     }
 
-    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
     {
         try {
             if (AbstractUid::class === $type) {
@@ -88,7 +88,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
         }
     }
 
-    public function supportsDenormalization(mixed $data, string $type, string $format = null, array $context = []): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null, array $context = []): bool
     {
         if (AbstractUid::class === $type) {
             trigger_deprecation('symfony/serializer', '6.1', 'Supporting denormalization for the "%s" type in "%s" is deprecated, use one of "%s" child class instead.', AbstractUid::class, __CLASS__, AbstractUid::class);
diff --git a/Normalizer/UnwrappingDenormalizer.php b/Normalizer/UnwrappingDenormalizer.php
index 3708b1a08..aa4d74c45 100644
--- a/Normalizer/UnwrappingDenormalizer.php
+++ b/Normalizer/UnwrappingDenormalizer.php
@@ -28,7 +28,7 @@ final class UnwrappingDenormalizer implements DenormalizerInterface, SerializerA
 
     private readonly PropertyAccessorInterface $propertyAccessor;
 
-    public function __construct(PropertyAccessorInterface $propertyAccessor = null)
+    public function __construct(?PropertyAccessorInterface $propertyAccessor = null)
     {
         $this->propertyAccessor = $propertyAccessor ?? PropertyAccess::createPropertyAccessor();
     }
@@ -38,7 +38,7 @@ public function getSupportedTypes(?string $format): array
         return ['*' => false];
     }
 
-    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
     {
         $propertyPath = $context[self::UNWRAP_PATH];
         $context['unwrapped'] = true;
@@ -58,7 +58,7 @@ public function denormalize(mixed $data, string $type, string $format = null, ar
         return $this->serializer->denormalize($data, $type, $format, $context);
     }
 
-    public function supportsDenormalization(mixed $data, string $type, string $format = null, array $context = []): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null, array $context = []): bool
     {
         return \array_key_exists(self::UNWRAP_PATH, $context) && !isset($context['unwrapped']);
     }
diff --git a/Serializer.php b/Serializer.php
index f65281492..7044c2f20 100644
--- a/Serializer.php
+++ b/Serializer.php
@@ -152,7 +152,7 @@ final public function deserialize(mixed $data, string $type, string $format, arr
         return $this->denormalize($data, $type, $format, $context);
     }
 
-    public function normalize(mixed $data, string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
+    public function normalize(mixed $data, ?string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
     {
         // If a normalizer supports the given data, use it
         if ($normalizer = $this->getNormalizer($data, $format, $context)) {
@@ -195,7 +195,7 @@ public function normalize(mixed $data, string $format = null, array $context = [
      * @throws NotNormalizableValueException
      * @throws PartialDenormalizationException Occurs when one or more properties of $type fails to denormalize
      */
-    public function denormalize(mixed $data, string $type, string $format = null, array $context = []): mixed
+    public function denormalize(mixed $data, string $type, ?string $format = null, array $context = []): mixed
     {
         if (isset($context[DenormalizerInterface::COLLECT_DENORMALIZATION_ERRORS], $context['not_normalizable_value_exceptions'])) {
             throw new LogicException('Passing a value for "not_normalizable_value_exceptions" context key is not allowed.');
@@ -252,12 +252,12 @@ public function getSupportedTypes(?string $format): array
         return ['*' => false];
     }
 
-    public function supportsNormalization(mixed $data, string $format = null, array $context = []): bool
+    public function supportsNormalization(mixed $data, ?string $format = null, array $context = []): bool
     {
         return null !== $this->getNormalizer($data, $format, $context);
     }
 
-    public function supportsDenormalization(mixed $data, string $type, string $format = null, array $context = []): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null, array $context = []): bool
     {
         return isset(self::SCALAR_TYPES[$type]) || null !== $this->getDenormalizer($data, $type, $format, $context);
     }
diff --git a/Tests/Debug/TraceableSerializerTest.php b/Tests/Debug/TraceableSerializerTest.php
index 9cc43d40a..ea3c851c6 100644
--- a/Tests/Debug/TraceableSerializerTest.php
+++ b/Tests/Debug/TraceableSerializerTest.php
@@ -140,7 +140,7 @@ public function deserialize(mixed $data, string $type, string $format, array $co
         return 'deserialized';
     }
 
-    public function normalize(mixed $object, string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
+    public function normalize(mixed $object, ?string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
     {
         return 'normalized';
     }
@@ -150,17 +150,17 @@ public function getSupportedTypes(?string $format): array
         return ['*' => false];
     }
 
-    public function supportsNormalization(mixed $data, string $format = null, array $context = []): bool
+    public function supportsNormalization(mixed $data, ?string $format = null, array $context = []): bool
     {
         return true;
     }
 
-    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
     {
         return 'denormalized';
     }
 
-    public function supportsDenormalization(mixed $data, string $type, string $format = null, array $context = []): bool
+    public function supportsDenormalization(mixed $data, string $type, ?string $format = null, array $context = []): bool
     {
         return true;
     }
diff --git a/Tests/Fixtures/DummyWithWithVariadicParameterConstructor.php b/Tests/Fixtures/DummyWithWithVariadicParameterConstructor.php
new file mode 100644
index 000000000..7b3819ac9
--- /dev/null
+++ b/Tests/Fixtures/DummyWithWithVariadicParameterConstructor.php
@@ -0,0 +1,44 @@
+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Serializer\Tests\Fixtures;
+
+class DummyWithWithVariadicParameterConstructor
+{
+    private $foo;
+
+    private $bar;
+
+    private $baz;
+
+    public function __construct(string $foo, int $bar = 1, Dummy ...$baz)
+    {
+        $this->foo = $foo;
+        $this->bar = $bar;
+        $this->baz = $baz;
+    }
+
+    public function getFoo(): string
+    {
+        return $this->foo;
+    }
+
+    public function getBar(): int
+    {
+        return $this->bar;
+    }
+
+    /** @return Dummy[] */
+    public function getBaz(): array
+    {
+        return $this->baz;
+    }
+}
diff --git a/Tests/Normalizer/AbstractNormalizerTest.php b/Tests/Normalizer/AbstractNormalizerTest.php
index 9720d323b..1166a37e9 100644
--- a/Tests/Normalizer/AbstractNormalizerTest.php
+++ b/Tests/Normalizer/AbstractNormalizerTest.php
@@ -30,6 +30,7 @@
 use Symfony\Component\Serializer\Tests\Fixtures\AbstractNormalizerDummy;
 use Symfony\Component\Serializer\Tests\Fixtures\Annotations\IgnoreDummy;
 use Symfony\Component\Serializer\Tests\Fixtures\Dummy;
+use Symfony\Component\Serializer\Tests\Fixtures\DummyWithWithVariadicParameterConstructor;
 use Symfony\Component\Serializer\Tests\Fixtures\NullableConstructorArgumentDummy;
 use Symfony\Component\Serializer\Tests\Fixtures\NullableOptionalConstructorArgumentDummy;
 use Symfony\Component\Serializer\Tests\Fixtures\StaticConstructorDummy;
@@ -255,6 +256,25 @@ public static function getNormalizer()
         yield [new ObjectNormalizer(null, null, null, $extractor)];
     }
 
+    public function testVariadicConstructorDenormalization()
+    {
+        $data = [
+            'foo' => 'woo',
+            'baz' => [
+                ['foo' => null, 'bar' => null, 'baz' => null, 'qux' => null],
+                ['foo' => null, 'bar' => null, 'baz' => null, 'qux' => null],
+            ],
+        ];
+
+        $normalizer = new ObjectNormalizer();
+        $normalizer->setSerializer(new Serializer([$normalizer]));
+
+        $expected = new DummyWithWithVariadicParameterConstructor('woo', 1, new Dummy(), new Dummy());
+        $actual = $normalizer->denormalize($data, DummyWithWithVariadicParameterConstructor::class);
+
+        $this->assertEquals($expected, $actual);
+    }
+
     public static function getNormalizerWithCustomNameConverter()
     {
         $extractor = new PhpDocExtractor();
diff --git a/Tests/Normalizer/AbstractObjectNormalizerTest.php b/Tests/Normalizer/AbstractObjectNormalizerTest.php
index fa34dcf20..a07fcd54e 100644
--- a/Tests/Normalizer/AbstractObjectNormalizerTest.php
+++ b/Tests/Normalizer/AbstractObjectNormalizerTest.php
@@ -774,7 +774,7 @@ public function testDefaultExcludeFromCacheKey()
         $object->bar = 'not called';
 
         $normalizer = new class(null, null, null, null, null, [AbstractObjectNormalizer::EXCLUDE_FROM_CACHE_KEY => ['foo']]) extends AbstractObjectNormalizerDummy {
-            public function supportsNormalization(mixed $data, string $format = null, array $context = []): bool
+            public function supportsNormalization(mixed $data, ?string $format = null, array $context = []): bool
             {
                 AbstractObjectNormalizerTest::assertContains('foo', $this->defaultContext[ObjectNormalizer::EXCLUDE_FROM_CACHE_KEY]);
                 $data->bar = 'called';
@@ -862,17 +862,17 @@ protected function getAllowedAttributes($classOrObject, array $context, bool $at
                 return ['foo'];
             }
 
-            protected function extractAttributes(object $object, string $format = null, array $context = []): array
+            protected function extractAttributes(object $object, ?string $format = null, array $context = []): array
             {
                 return [];
             }
 
-            protected function getAttributeValue(object $object, string $attribute, string $format = null, array $context = []): mixed
+            protected function getAttributeValue(object $object, string $attribute, ?string $format = null, array $context = []): mixed
             {
                 return $object->$attribute;
             }
 
-            protected function setAttributeValue(object $object, string $attribute, $value, string $format = null, array $context = []): void
+            protected function setAttributeValue(object $object, string $attribute, $value, ?string $format = null, array $context = []): void
             {
             }
         };
@@ -922,6 +922,116 @@ public function testDenormalizeUntypedStringObject()
         $this->assertEquals(new DummyWithStringObject(new DummyString()), $actual);
         $this->assertEquals('', $actual->value->value);
     }
+
+    public function testProvidingContextCacheKeyGeneratesSameChildContextCacheKey()
+    {
+        $foobar = new Dummy();
+        $foobar->foo = new EmptyDummy();
+        $foobar->bar = 'bar';
+        $foobar->baz = 'baz';
+
+        $normalizer = new class() extends AbstractObjectNormalizerDummy {
+            public $childContextCacheKey;
+
+            protected function extractAttributes(object $object, string $format = null, array $context = []): array
+            {
+                return array_keys((array) $object);
+            }
+
+            protected function getAttributeValue(object $object, string $attribute, string $format = null, array $context = []): mixed
+            {
+                return $object->{$attribute};
+            }
+
+            protected function createChildContext(array $parentContext, string $attribute, ?string $format): array
+            {
+                $childContext = parent::createChildContext($parentContext, $attribute, $format);
+                $this->childContextCacheKey = $childContext['cache_key'];
+
+                return $childContext;
+            }
+        };
+
+        $serializer = new Serializer([$normalizer]);
+
+        $serializer->normalize($foobar, null, ['cache_key' => 'hardcoded', 'iri' => '/dummy/1']);
+        $firstChildContextCacheKey = $normalizer->childContextCacheKey;
+
+        $serializer->normalize($foobar, null, ['cache_key' => 'hardcoded', 'iri' => '/dummy/2']);
+        $secondChildContextCacheKey = $normalizer->childContextCacheKey;
+
+        $this->assertSame($firstChildContextCacheKey, $secondChildContextCacheKey);
+    }
+
+    public function testChildContextKeepsOriginalContextCacheKey()
+    {
+        $foobar = new Dummy();
+        $foobar->foo = new EmptyDummy();
+        $foobar->bar = 'bar';
+        $foobar->baz = 'baz';
+
+        $normalizer = new class() extends AbstractObjectNormalizerDummy {
+            public $childContextCacheKey;
+
+            protected function extractAttributes(object $object, string $format = null, array $context = []): array
+            {
+                return array_keys((array) $object);
+            }
+
+            protected function getAttributeValue(object $object, string $attribute, string $format = null, array $context = []): mixed
+            {
+                return $object->{$attribute};
+            }
+
+            protected function createChildContext(array $parentContext, string $attribute, ?string $format): array
+            {
+                $childContext = parent::createChildContext($parentContext, $attribute, $format);
+                $this->childContextCacheKey = $childContext['cache_key'];
+
+                return $childContext;
+            }
+        };
+
+        $serializer = new Serializer([$normalizer]);
+        $serializer->normalize($foobar, null, ['cache_key' => 'hardcoded', 'iri' => '/dummy/1']);
+
+        $this->assertSame('hardcoded-foo', $normalizer->childContextCacheKey);
+    }
+
+    public function testChildContextCacheKeyStaysFalseWhenOriginalCacheKeyIsFalse()
+    {
+        $foobar = new Dummy();
+        $foobar->foo = new EmptyDummy();
+        $foobar->bar = 'bar';
+        $foobar->baz = 'baz';
+
+        $normalizer = new class() extends AbstractObjectNormalizerDummy {
+            public $childContextCacheKey;
+
+            protected function extractAttributes(object $object, string $format = null, array $context = []): array
+            {
+                return array_keys((array) $object);
+            }
+
+            protected function getAttributeValue(object $object, string $attribute, string $format = null, array $context = []): mixed
+            {
+                return $object->{$attribute};
+            }
+
+            protected function createChildContext(array $parentContext, string $attribute, ?string $format): array
+            {
+                $childContext = parent::createChildContext($parentContext, $attribute, $format);
+                $this->childContextCacheKey = $childContext['cache_key'];
+
+                return $childContext;
+            }
+        };
+
+        $serializer = new Serializer([$normalizer]);
+        $serializer->normalize($foobar, null, ['cache_key' => false]);
+
+        $this->assertFalse($normalizer->childContextCacheKey);
+    }
 }
 
 class AbstractObjectNormalizerDummy extends AbstractObjectNormalizer
@@ -931,26 +1041,26 @@ public function getSupportedTypes(?string $format): array
         return ['*' => false];
     }
 
-    protected function extractAttributes(object $object, string $format = null, array $context = []): array
+    protected function extractAttributes(object $object, ?string $format = null, array $context = []): array
     {
         return [];
     }
 
-    protected function getAttributeValue(object $object, string $attribute, string $format = null, array $context = []): mixed
+    protected function getAttributeValue(object $object, string $attribute, ?string $format = null, array $context = []): mixed
     {
     }
 
-    protected function setAttributeValue(object $object, string $attribute, $value, string $format = null, array $context = []): void
+    protected function setAttributeValue(object $object, string $attribute, $value, ?string $format = null, array $context = []): void
     {
         $object->$attribute = $value;
     }
 
-    protected function isAllowedAttribute($classOrObject, string $attribute, string $format = null, array $context = []): bool
+    protected function isAllowedAttribute($classOrObject, string $attribute, ?string $format = null, array $context = []): bool
     {
         return \in_array($attribute, ['foo', 'baz', 'quux', 'value']);
     }
 
-    public function instantiateObject(array &$data, string $class, array &$context, \ReflectionClass $reflectionClass, $allowedAttributes, string $format = null): object
+    public function instantiateObject(array &$data, string $class, array &$context, \ReflectionClass $reflectionClass, $allowedAttributes, ?string $format = null): object
     {
         return parent::instantiateObject($data, $class, $context, $reflectionClass, $allowedAttributes, $format);
     }
@@ -1140,15 +1250,15 @@ public function getSupportedTypes(?string $format): array
         return ['*' => false];
     }
 
-    protected function extractAttributes(object $object, string $format = null, array $context = []): array
+    protected function extractAttributes(object $object, ?string $format = null, array $context = []): array
     {
     }
 
-    protected function getAttributeValue(object $object, string $attribute, string $format = null, array $context = []): mixed
+    protected function getAttributeValue(object $object, string $attribute, ?string $format = null, array $context = []): mixed
     {
     }
 
-    protected function setAttributeValue(object $object, string $attribute, $value, string $format = null, array $context = []): void
+    protected function setAttributeValue(object $object, string $attribute, $value, ?string $format = null, array $context = []): void
     {
         if (property_exists($object, $attribute)) {
             $object->$attribute = $value;
@@ -1238,7 +1348,7 @@ public function deserialize($data, string $type, string $format, array $context
     {
     }
 
-    public function denormalize($data, string $type, string $format = null, array $context = []): mixed
+    public function denormalize($data, string $type, ?string $format = null, array $context = []): mixed
     {
         foreach ($this->normalizers as $normalizer) {
             if ($normalizer instanceof DenormalizerInterface && $normalizer->supportsDenormalization($data, $type, $format, $context)) {
@@ -1254,7 +1364,7 @@ public function getSupportedTypes(?string $format): array
         return ['*' => false];
     }
 
-    public function supportsDenormalization($data, string $type, string $format = null, array $context = []): bool
+    public function supportsDenormalization($data, string $type, ?string $format = null, array $context = []): bool
     {
         return true;
     }
@@ -1267,25 +1377,25 @@ public function getSupportedTypes(?string $format): array
         return ['*' => false];
     }
 
-    protected function extractAttributes(object $object, string $format = null, array $context = []): array
+    protected function extractAttributes(object $object, ?string $format = null, array $context = []): array
     {
     }
 
-    protected function getAttributeValue(object $object, string $attribute, string $format = null, array $context = []): mixed
+    protected function getAttributeValue(object $object, string $attribute, ?string $format = null, array $context = []): mixed
     {
     }
 
-    protected function setAttributeValue(object $object, string $attribute, $value, string $format = null, array $context = []): void
+    protected function setAttributeValue(object $object, string $attribute, $value, ?string $format = null, array $context = []): void
     {
         $object->$attribute = $value;
     }
 
-    protected function isAllowedAttribute($classOrObject, string $attribute, string $format = null, array $context = []): bool
+    protected function isAllowedAttribute($classOrObject, string $attribute, ?string $format = null, array $context = []): bool
     {
         return true;
     }
 
-    public function instantiateObject(array &$data, string $class, array &$context, \ReflectionClass $reflectionClass, $allowedAttributes, string $format = null): object
+    public function instantiateObject(array &$data, string $class, array &$context, \ReflectionClass $reflectionClass, $allowedAttributes, ?string $format = null): object
     {
         return parent::instantiateObject($data, $class, $context, $reflectionClass, $allowedAttributes, $format);
     }
@@ -1309,7 +1419,7 @@ class ArrayDenormalizerDummy implements DenormalizerInterface, SerializerAwareIn
     /**
      * @throws NotNormalizableValueException
      */
-    public function denormalize($data, string $type, string $format = null, array $context = []): mixed
+    public function denormalize($data, string $type, ?string $format = null, array $context = []): mixed
     {
         $serializer = $this->serializer;
         $type = substr($type, 0, -2);
@@ -1326,7 +1436,7 @@ public function getSupportedTypes(?string $format): array
         return $this->serializer->getSupportedTypes($format);
     }
 
-    public function supportsDenormalization($data, string $type, string $format = null, array $context = []): bool
+    public function supportsDenormalization($data, string $type, ?string $format = null, array $context = []): bool
     {
         return str_ends_with($type, '[]')
             && $this->serializer->supportsDenormalization($data, substr($type, 0, -2), $format, $context);
diff --git a/Tests/Normalizer/ConstraintViolationListNormalizerTest.php b/Tests/Normalizer/ConstraintViolationListNormalizerTest.php
index 8e8df388d..bb045b8ae 100644
--- a/Tests/Normalizer/ConstraintViolationListNormalizerTest.php
+++ b/Tests/Normalizer/ConstraintViolationListNormalizerTest.php
@@ -116,7 +116,7 @@ public function testNormalizeWithNameConverter()
     /**
      * @dataProvider payloadFieldsProvider
      */
-    public function testNormalizePayloadFields($fields, array $expected = null)
+    public function testNormalizePayloadFields($fields, ?array $expected = null)
     {
         $constraint = new NotNull();
         $constraint->payload = ['severity' => 'warning', 'anotherField2' => 'aValue'];
diff --git a/Tests/Normalizer/Features/CallbacksObject.php b/Tests/Normalizer/Features/CallbacksObject.php
index 19ad3f547..d484f8b8a 100644
--- a/Tests/Normalizer/Features/CallbacksObject.php
+++ b/Tests/Normalizer/Features/CallbacksObject.php
@@ -20,7 +20,7 @@ class CallbacksObject
      */
     public $foo;
 
-    public function __construct($bar = null, string $foo = null)
+    public function __construct($bar = null, ?string $foo = null)
     {
         $this->bar = $bar;
         $this->foo = $foo;
diff --git a/Tests/Normalizer/ObjectNormalizerTest.php b/Tests/Normalizer/ObjectNormalizerTest.php
index 153cab759..3658f1e1c 100644
--- a/Tests/Normalizer/ObjectNormalizerTest.php
+++ b/Tests/Normalizer/ObjectNormalizerTest.php
@@ -93,7 +93,7 @@ protected function setUp(): void
         $this->createNormalizer();
     }
 
-    private function createNormalizer(array $defaultContext = [], ClassMetadataFactoryInterface $classMetadataFactory = null)
+    private function createNormalizer(array $defaultContext = [], ?ClassMetadataFactoryInterface $classMetadataFactory = null)
     {
         $this->serializer = $this->createMock(ObjectSerializerNormalizer::class);
         $this->normalizer = new ObjectNormalizer($classMetadataFactory, null, null, null, null, null, $defaultContext);
@@ -775,12 +775,12 @@ public function testDenormalizeFalsePseudoType()
     public function testAdvancedNameConverter()
     {
         $nameConverter = new class() implements AdvancedNameConverterInterface {
-            public function normalize(string $propertyName, string $class = null, string $format = null, array $context = []): string
+            public function normalize(string $propertyName, ?string $class = null, ?string $format = null, array $context = []): string
             {
                 return sprintf('%s-%s-%s-%s', $propertyName, $class, $format, $context['foo']);
             }
 
-            public function denormalize(string $propertyName, string $class = null, string $format = null, array $context = []): string
+            public function denormalize(string $propertyName, ?string $class = null, ?string $format = null, array $context = []): string
             {
                 return sprintf('%s-%s-%s-%s', $propertyName, $class, $format, $context['foo']);
             }
@@ -1074,7 +1074,7 @@ class DummyWithConstructorObjectAndDefaultValue
     private $foo;
     private $inner;
 
-    public function __construct($foo = 'a', ObjectInner $inner = null)
+    public function __construct($foo = 'a', ?ObjectInner $inner = null)
     {
         $this->foo = $foo;
         $this->inner = $inner;
diff --git a/Tests/Normalizer/TestDenormalizer.php b/Tests/Normalizer/TestDenormalizer.php
index 70518c797..cd51b3c19 100644
--- a/Tests/Normalizer/TestDenormalizer.php
+++ b/Tests/Normalizer/TestDenormalizer.php
@@ -20,7 +20,7 @@
  */
 class TestDenormalizer implements DenormalizerInterface
 {
-    public function denormalize($data, string $type, string $format = null, array $context = []): mixed
+    public function denormalize($data, string $type, ?string $format = null, array $context = []): mixed
     {
     }
 
@@ -29,7 +29,7 @@ public function getSupportedTypes(?string $format): array
         return ['*' => false];
     }
 
-    public function supportsDenormalization($data, string $type, string $format = null, array $context = []): bool
+    public function supportsDenormalization($data, string $type, ?string $format = null, array $context = []): bool
     {
         return true;
     }
diff --git a/Tests/Normalizer/TestNormalizer.php b/Tests/Normalizer/TestNormalizer.php
index 26e5917e7..941fef42b 100644
--- a/Tests/Normalizer/TestNormalizer.php
+++ b/Tests/Normalizer/TestNormalizer.php
@@ -20,7 +20,7 @@
  */
 class TestNormalizer implements NormalizerInterface
 {
-    public function normalize($object, string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
+    public function normalize($object, ?string $format = null, array $context = []): array|string|int|float|bool|\ArrayObject|null
     {
         return null;
     }
@@ -30,7 +30,7 @@ public function getSupportedTypes(?string $format): array
         return ['*' => false];
     }
 
-    public function supportsNormalization($data, string $format = null, array $context = []): bool
+    public function supportsNormalization($data, ?string $format = null, array $context = []): bool
     {
         return true;
     }
diff --git a/Tests/SerializerTest.php b/Tests/SerializerTest.php
index daabf8e6c..2a79e9a97 100644
--- a/Tests/SerializerTest.php
+++ b/Tests/SerializerTest.php
@@ -1064,7 +1064,7 @@ public function testCollectDenormalizationErrors(?ClassMetadataFactory $classMet
                 'expectedTypes' => [
                     'unknown',
                 ],
-                'path' => 'php74FullWithConstructor',
+                'path' => 'php74FullWithConstructor.constructorArgument',
                 'useMessageForUser' => true,
                 'message' => 'Failed to create object because the class misses the "constructorArgument" property.',
             ],
@@ -1197,6 +1197,70 @@ public function testCollectDenormalizationErrors2(?ClassMetadataFactory $classMe
         $this->assertSame($expected, $exceptionsAsArray);
     }
 
+    public function testCollectDenormalizationErrorsWithoutTypeExtractor()
+    {
+        $json = '
+        {
+            "string": [],
+            "int": [],
+            "float": []
+        }';
+
+        $serializer = new Serializer([new ObjectNormalizer()], ['json' => new JsonEncoder()]);
+
+        try {
+            $serializer->deserialize($json, Php74Full::class, 'json', [
+                DenormalizerInterface::COLLECT_DENORMALIZATION_ERRORS => true,
+            ]);
+
+            $this->fail();
+        } catch (\Throwable $th) {
+            $this->assertInstanceOf(PartialDenormalizationException::class, $th);
+        }
+
+        $this->assertInstanceOf(Php74Full::class, $th->getData());
+
+        $exceptionsAsArray = array_map(fn (NotNormalizableValueException $e): array => [
+            'currentType' => $e->getCurrentType(),
+            'expectedTypes' => $e->getExpectedTypes(),
+            'path' => $e->getPath(),
+            'useMessageForUser' => $e->canUseMessageForUser(),
+            'message' => $e->getMessage(),
+        ], $th->getErrors());
+
+        $expected = [
+            [
+                'currentType' => 'array',
+                'expectedTypes' => [
+                    'unknown',
+                ],
+                'path' => 'string',
+                'useMessageForUser' => false,
+                'message' => 'Failed to denormalize attribute "string" value for class "Symfony\\Component\\Serializer\\Tests\\Fixtures\\Php74Full": Expected argument of type "string", "array" given at property path "string".',
+            ],
+            [
+                'currentType' => 'array',
+                'expectedTypes' => [
+                    'unknown',
+                ],
+                'path' => 'int',
+                'useMessageForUser' => false,
+                'message' => 'Failed to denormalize attribute "int" value for class "Symfony\\Component\\Serializer\\Tests\\Fixtures\\Php74Full": Expected argument of type "int", "array" given at property path "int".',
+            ],
+            [
+                'currentType' => 'array',
+                'expectedTypes' => [
+                    'unknown',
+                ],
+                'path' => 'float',
+                'useMessageForUser' => false,
+                'message' => 'Failed to denormalize attribute "float" value for class "Symfony\\Component\\Serializer\\Tests\\Fixtures\\Php74Full": Expected argument of type "float", "array" given at property path "float".',
+            ],
+        ];
+
+        $this->assertSame($expected, $exceptionsAsArray);
+    }
+
     /**
      * @dataProvider provideCollectDenormalizationErrors
      */
@@ -1248,7 +1312,7 @@ public function testCollectDenormalizationErrorsWithConstructor(?ClassMetadataFa
                 'expectedTypes' => [
                     'unknown',
                 ],
-                'path' => null,
+                'path' => 'string',
                 'useMessageForUser' => true,
                 'message' => 'Failed to create object because the class misses the "string" property.',
             ],
@@ -1257,7 +1321,7 @@ public function testCollectDenormalizationErrorsWithConstructor(?ClassMetadataFa
                 'expectedTypes' => [
                     'unknown',
                 ],
-                'path' => null,
+                'path' => 'int',
                 'useMessageForUser' => true,
                 'message' => 'Failed to create object because the class misses the "int" property.',
             ],
@@ -1307,7 +1371,7 @@ public function testCollectDenormalizationErrorsWithInvalidConstructorTypes()
             [
                 'currentType' => 'string',
                 'expectedTypes' => [
-                    0 => 'bool',
+                    'bool',
                 ],
                 'path' => 'bool',
                 'useMessageForUser' => false,
@@ -1316,7 +1380,7 @@ public function testCollectDenormalizationErrorsWithInvalidConstructorTypes()
             [
                 'currentType' => 'bool',
                 'expectedTypes' => [
-                    0 => 'int',
+                    'int',
                 ],
                 'path' => 'int',
                 'useMessageForUser' => false,
@@ -1544,7 +1608,7 @@ public function testPartialDenormalizationWithMissingConstructorTypes()
                 'expectedTypes' => [
                     'unknown',
                 ],
-                'path' => null,
+                'path' => 'two',
                 'useMessageForUser' => true,
                 'message' => 'Failed to create object because the class misses the "two" property.',
             ],
diff --git a/composer.json b/composer.json
index 5efabab21..d0f66972f 100644
--- a/composer.json
+++ b/composer.json
@@ -33,7 +33,7 @@
         "symfony/http-foundation": "^5.4|^6.0",
         "symfony/http-kernel": "^5.4|^6.0",
         "symfony/mime": "^5.4|^6.0",
-        "symfony/property-access": "^5.4|^6.0",
+        "symfony/property-access": "^5.4.26|^6.3",
         "symfony/property-info": "^5.4.24|^6.2.11",
         "symfony/uid": "^5.4|^6.0",
         "symfony/validator": "^5.4|^6.0",