diff --git a/src/Symfony/Component/VarDumper/Caster/CutStub.php b/src/Symfony/Component/VarDumper/Caster/CutStub.php
index 464c6dbd1905d..b5a96a02cfcdc 100644
--- a/src/Symfony/Component/VarDumper/Caster/CutStub.php
+++ b/src/Symfony/Component/VarDumper/Caster/CutStub.php
@@ -20,7 +20,7 @@
  */
 class CutStub extends Stub
 {
-    public function __construct($value)
+    public function __construct(mixed $value)
     {
         $this->value = $value;
 
diff --git a/src/Symfony/Component/VarDumper/Caster/DsPairStub.php b/src/Symfony/Component/VarDumper/Caster/DsPairStub.php
index a1dcc156183e9..22112af9c073d 100644
--- a/src/Symfony/Component/VarDumper/Caster/DsPairStub.php
+++ b/src/Symfony/Component/VarDumper/Caster/DsPairStub.php
@@ -18,7 +18,7 @@
  */
 class DsPairStub extends Stub
 {
-    public function __construct($key, $value)
+    public function __construct(string|int $key, mixed $value)
     {
         $this->value = [
             Caster::PREFIX_VIRTUAL.'key' => $key,
diff --git a/src/Symfony/Component/VarDumper/Caster/LinkStub.php b/src/Symfony/Component/VarDumper/Caster/LinkStub.php
index 0aa076a265846..e937cdc3efdc4 100644
--- a/src/Symfony/Component/VarDumper/Caster/LinkStub.php
+++ b/src/Symfony/Component/VarDumper/Caster/LinkStub.php
@@ -23,7 +23,7 @@ class LinkStub extends ConstStub
     private static $vendorRoots;
     private static $composerRoots;
 
-    public function __construct($label, int $line = 0, $href = null)
+    public function __construct(string $label, int $line = 0, string $href = null)
     {
         $this->value = $label;
 
diff --git a/src/Symfony/Component/VarDumper/Caster/RdKafkaCaster.php b/src/Symfony/Component/VarDumper/Caster/RdKafkaCaster.php
index c3e4eb9f341c6..8053363956637 100644
--- a/src/Symfony/Component/VarDumper/Caster/RdKafkaCaster.php
+++ b/src/Symfony/Component/VarDumper/Caster/RdKafkaCaster.php
@@ -31,7 +31,7 @@
  */
 class RdKafkaCaster
 {
-    public static function castKafkaConsumer(KafkaConsumer $c, array $a, Stub $stub, $isNested)
+    public static function castKafkaConsumer(KafkaConsumer $c, array $a, Stub $stub, bool $isNested)
     {
         $prefix = Caster::PREFIX_VIRTUAL;
 
@@ -51,7 +51,7 @@ public static function castKafkaConsumer(KafkaConsumer $c, array $a, Stub $stub,
         return $a;
     }
 
-    public static function castTopic(Topic $c, array $a, Stub $stub, $isNested)
+    public static function castTopic(Topic $c, array $a, Stub $stub, bool $isNested)
     {
         $prefix = Caster::PREFIX_VIRTUAL;
 
@@ -75,7 +75,7 @@ public static function castTopicPartition(TopicPartition $c, array $a)
         return $a;
     }
 
-    public static function castMessage(Message $c, array $a, Stub $stub, $isNested)
+    public static function castMessage(Message $c, array $a, Stub $stub, bool $isNested)
     {
         $prefix = Caster::PREFIX_VIRTUAL;
 
@@ -86,7 +86,7 @@ public static function castMessage(Message $c, array $a, Stub $stub, $isNested)
         return $a;
     }
 
-    public static function castConf(Conf $c, array $a, Stub $stub, $isNested)
+    public static function castConf(Conf $c, array $a, Stub $stub, bool $isNested)
     {
         $prefix = Caster::PREFIX_VIRTUAL;
 
@@ -97,7 +97,7 @@ public static function castConf(Conf $c, array $a, Stub $stub, $isNested)
         return $a;
     }
 
-    public static function castTopicConf(TopicConf $c, array $a, Stub $stub, $isNested)
+    public static function castTopicConf(TopicConf $c, array $a, Stub $stub, bool $isNested)
     {
         $prefix = Caster::PREFIX_VIRTUAL;
 
@@ -108,7 +108,7 @@ public static function castTopicConf(TopicConf $c, array $a, Stub $stub, $isNest
         return $a;
     }
 
-    public static function castRdKafka(\RdKafka $c, array $a, Stub $stub, $isNested)
+    public static function castRdKafka(\RdKafka $c, array $a, Stub $stub, bool $isNested)
     {
         $prefix = Caster::PREFIX_VIRTUAL;
 
@@ -121,14 +121,14 @@ public static function castRdKafka(\RdKafka $c, array $a, Stub $stub, $isNested)
         return $a;
     }
 
-    public static function castCollectionMetadata(CollectionMetadata $c, array $a, Stub $stub, $isNested)
+    public static function castCollectionMetadata(CollectionMetadata $c, array $a, Stub $stub, bool $isNested)
     {
         $a += iterator_to_array($c);
 
         return $a;
     }
 
-    public static function castTopicMetadata(TopicMetadata $c, array $a, Stub $stub, $isNested)
+    public static function castTopicMetadata(TopicMetadata $c, array $a, Stub $stub, bool $isNested)
     {
         $prefix = Caster::PREFIX_VIRTUAL;
 
@@ -140,7 +140,7 @@ public static function castTopicMetadata(TopicMetadata $c, array $a, Stub $stub,
         return $a;
     }
 
-    public static function castPartitionMetadata(PartitionMetadata $c, array $a, Stub $stub, $isNested)
+    public static function castPartitionMetadata(PartitionMetadata $c, array $a, Stub $stub, bool $isNested)
     {
         $prefix = Caster::PREFIX_VIRTUAL;
 
@@ -153,7 +153,7 @@ public static function castPartitionMetadata(PartitionMetadata $c, array $a, Stu
         return $a;
     }
 
-    public static function castBrokerMetadata(BrokerMetadata $c, array $a, Stub $stub, $isNested)
+    public static function castBrokerMetadata(BrokerMetadata $c, array $a, Stub $stub, bool $isNested)
     {
         $prefix = Caster::PREFIX_VIRTUAL;
 
@@ -166,7 +166,7 @@ public static function castBrokerMetadata(BrokerMetadata $c, array $a, Stub $stu
         return $a;
     }
 
-    private static function extractMetadata($c)
+    private static function extractMetadata(KafkaConsumer|\RdKafka $c)
     {
         $prefix = Caster::PREFIX_VIRTUAL;
 
diff --git a/src/Symfony/Component/VarDumper/Caster/RedisCaster.php b/src/Symfony/Component/VarDumper/Caster/RedisCaster.php
index 8f97eaad3bd3f..eac25a12a8b56 100644
--- a/src/Symfony/Component/VarDumper/Caster/RedisCaster.php
+++ b/src/Symfony/Component/VarDumper/Caster/RedisCaster.php
@@ -102,10 +102,7 @@ public static function castRedisCluster(\RedisCluster $c, array $a, Stub $stub,
         return $a;
     }
 
-    /**
-     * @param \Redis|\RedisArray|\RedisCluster $redis
-     */
-    private static function getRedisOptions($redis, array $options = []): EnumStub
+    private static function getRedisOptions(\Redis|\RedisArray|\RedisCluster $redis, array $options = []): EnumStub
     {
         $serializer = $redis->getOption(\Redis::OPT_SERIALIZER);
         if (\is_array($serializer)) {
diff --git a/src/Symfony/Component/VarDumper/Caster/ResourceCaster.php b/src/Symfony/Component/VarDumper/Caster/ResourceCaster.php
index 6b2ed522364e7..6ae908524f6c1 100644
--- a/src/Symfony/Component/VarDumper/Caster/ResourceCaster.php
+++ b/src/Symfony/Component/VarDumper/Caster/ResourceCaster.php
@@ -48,7 +48,7 @@ public static function castProcess($process, array $a, Stub $stub, bool $isNeste
     public static function castStream($stream, array $a, Stub $stub, bool $isNested)
     {
         $a = stream_get_meta_data($stream) + static::castStreamContext($stream, $a, $stub, $isNested);
-        if (isset($a['uri'])) {
+        if ($a['uri'] ?? false) {
             $a['uri'] = new LinkStub($a['uri']);
         }
 
@@ -60,7 +60,7 @@ public static function castStreamContext($stream, array $a, Stub $stub, bool $is
         return @stream_context_get_params($stream) ?: $a;
     }
 
-    public static function castGd($gd, array $a, Stub $stub, $isNested)
+    public static function castGd($gd, array $a, Stub $stub, bool $isNested)
     {
         $a['size'] = imagesx($gd).'x'.imagesy($gd);
         $a['trueColor'] = imageistruecolor($gd);
diff --git a/src/Symfony/Component/VarDumper/Caster/SplCaster.php b/src/Symfony/Component/VarDumper/Caster/SplCaster.php
index 80af4c4c3e38d..c0dbecfc6c77f 100644
--- a/src/Symfony/Component/VarDumper/Caster/SplCaster.php
+++ b/src/Symfony/Component/VarDumper/Caster/SplCaster.php
@@ -39,7 +39,7 @@ public static function castArrayIterator(\ArrayIterator $c, array $a, Stub $stub
         return self::castSplArray($c, $a, $stub, $isNested);
     }
 
-    public static function castHeap(\Iterator $c, array $a, Stub $stub, $isNested)
+    public static function castHeap(\Iterator $c, array $a, Stub $stub, bool $isNested)
     {
         $a += [
             Caster::PREFIX_VIRTUAL.'heap' => iterator_to_array(clone $c),
@@ -121,7 +121,7 @@ public static function castFileInfo(\SplFileInfo $c, array $a, Stub $stub, bool
             }
         }
 
-        if (isset($a[$prefix.'realPath'])) {
+        if ($a[$prefix.'realPath'] ?? false) {
             $a[$prefix.'realPath'] = new LinkStub($a[$prefix.'realPath']);
         }
 
diff --git a/src/Symfony/Component/VarDumper/Cloner/AbstractCloner.php b/src/Symfony/Component/VarDumper/Cloner/AbstractCloner.php
index 1b7fa35eb7015..3b0e07229fa75 100644
--- a/src/Symfony/Component/VarDumper/Cloner/AbstractCloner.php
+++ b/src/Symfony/Component/VarDumper/Cloner/AbstractCloner.php
@@ -253,12 +253,11 @@ public function setMinDepth(int $minDepth)
     /**
      * Clones a PHP variable.
      *
-     * @param mixed $var    Any PHP variable
-     * @param int   $filter A bit field of Caster::EXCLUDE_* constants
+     * @param int $filter A bit field of Caster::EXCLUDE_* constants
      *
      * @return Data The cloned variable represented by a Data object
      */
-    public function cloneVar($var, int $filter = 0)
+    public function cloneVar(mixed $var, int $filter = 0)
     {
         $this->prevErrorHandler = set_error_handler(function ($type, $msg, $file, $line, $context = []) {
             if (\E_RECOVERABLE_ERROR === $type || \E_USER_ERROR === $type) {
@@ -291,11 +290,9 @@ public function cloneVar($var, int $filter = 0)
     /**
      * Effectively clones the PHP variable.
      *
-     * @param mixed $var Any PHP variable
-     *
      * @return array The cloned variable represented in an array
      */
-    abstract protected function doClone($var);
+    abstract protected function doClone(mixed $var);
 
     /**
      * Casts an object to an array representation.
diff --git a/src/Symfony/Component/VarDumper/Cloner/ClonerInterface.php b/src/Symfony/Component/VarDumper/Cloner/ClonerInterface.php
index 7ed287a2ddf0d..fa1df1e8fd3db 100644
--- a/src/Symfony/Component/VarDumper/Cloner/ClonerInterface.php
+++ b/src/Symfony/Component/VarDumper/Cloner/ClonerInterface.php
@@ -19,9 +19,7 @@ interface ClonerInterface
     /**
      * Clones a PHP variable.
      *
-     * @param mixed $var Any PHP variable
-     *
      * @return Data The cloned variable represented by a Data object
      */
-    public function cloneVar($var);
+    public function cloneVar(mixed $var);
 }
diff --git a/src/Symfony/Component/VarDumper/Cloner/Data.php b/src/Symfony/Component/VarDumper/Cloner/Data.php
index c695a11aef71e..6027d666f2d6e 100644
--- a/src/Symfony/Component/VarDumper/Cloner/Data.php
+++ b/src/Symfony/Component/VarDumper/Cloner/Data.php
@@ -69,7 +69,7 @@ public function getType()
      *
      * @return string|int|float|bool|array|Data[]|null A native representation of the original value
      */
-    public function getValue($recursive = false)
+    public function getValue(array|bool $recursive = false)
     {
         $item = $this->data[$this->position][$this->key];
 
@@ -239,11 +239,9 @@ public function withContext(array $context)
     /**
      * Seeks to a specific key in nested data structures.
      *
-     * @param string|int $key The key to seek to
-     *
      * @return static|null Null if the key is not set
      */
-    public function seek($key)
+    public function seek(string|int $key)
     {
         $item = $this->data[$this->position][$this->key];
 
@@ -309,7 +307,7 @@ public function dump(DumperInterface $dumper)
      *
      * @param mixed $item A Stub object or the original value being dumped
      */
-    private function dumpItem(DumperInterface $dumper, Cursor $cursor, array &$refs, $item)
+    private function dumpItem(DumperInterface $dumper, Cursor $cursor, array &$refs, mixed $item)
     {
         $cursor->refIndex = 0;
         $cursor->softRefTo = $cursor->softRefHandle = $cursor->softRefCount = 0;
@@ -431,7 +429,7 @@ private function dumpChildren(DumperInterface $dumper, Cursor $parentCursor, arr
         return $hashCut;
     }
 
-    private function getStub($item)
+    private function getStub(mixed $item)
     {
         if (!$item || !\is_array($item)) {
             return $item;
diff --git a/src/Symfony/Component/VarDumper/Cloner/DumperInterface.php b/src/Symfony/Component/VarDumper/Cloner/DumperInterface.php
index 6d60b723c7f79..61d02d2406d66 100644
--- a/src/Symfony/Component/VarDumper/Cloner/DumperInterface.php
+++ b/src/Symfony/Component/VarDumper/Cloner/DumperInterface.php
@@ -20,11 +20,8 @@ interface DumperInterface
 {
     /**
      * Dumps a scalar value.
-     *
-     * @param string                $type  The PHP type of the value being dumped
-     * @param string|int|float|bool $value The scalar value being dumped
      */
-    public function dumpScalar(Cursor $cursor, string $type, $value);
+    public function dumpScalar(Cursor $cursor, string $type, string|int|float|bool|null $value);
 
     /**
      * Dumps a string.
@@ -38,19 +35,19 @@ public function dumpString(Cursor $cursor, string $str, bool $bin, int $cut);
     /**
      * Dumps while entering an hash.
      *
-     * @param int        $type     A Cursor::HASH_* const for the type of hash
-     * @param string|int $class    The object class, resource type or array count
-     * @param bool       $hasChild When the dump of the hash has child item
+     * @param int             $type     A Cursor::HASH_* const for the type of hash
+     * @param string|int|null $class    The object class, resource type or array count
+     * @param bool            $hasChild When the dump of the hash has child item
      */
-    public function enterHash(Cursor $cursor, int $type, $class, bool $hasChild);
+    public function enterHash(Cursor $cursor, int $type, string|int|null $class, bool $hasChild);
 
     /**
      * Dumps while leaving an hash.
      *
-     * @param int        $type     A Cursor::HASH_* const for the type of hash
-     * @param string|int $class    The object class, resource type or array count
-     * @param bool       $hasChild When the dump of the hash has child item
-     * @param int        $cut      The number of items the hash has been cut by
+     * @param int             $type     A Cursor::HASH_* const for the type of hash
+     * @param string|int|null $class    The object class, resource type or array count
+     * @param bool            $hasChild When the dump of the hash has child item
+     * @param int             $cut      The number of items the hash has been cut by
      */
-    public function leaveHash(Cursor $cursor, int $type, $class, bool $hasChild, int $cut);
+    public function leaveHash(Cursor $cursor, int $type, string|int|null $class, bool $hasChild, int $cut);
 }
diff --git a/src/Symfony/Component/VarDumper/Cloner/VarCloner.php b/src/Symfony/Component/VarDumper/Cloner/VarCloner.php
index a3aab6ec43353..4a6817c1c4869 100644
--- a/src/Symfony/Component/VarDumper/Cloner/VarCloner.php
+++ b/src/Symfony/Component/VarDumper/Cloner/VarCloner.php
@@ -22,7 +22,7 @@ class VarCloner extends AbstractCloner
     /**
      * {@inheritdoc}
      */
-    protected function doClone($var)
+    protected function doClone(mixed $var)
     {
         $len = 1;                       // Length of $queue
         $pos = 0;                       // Number of cloned items past the minimum depth
diff --git a/src/Symfony/Component/VarDumper/Dumper/CliDumper.php b/src/Symfony/Component/VarDumper/Dumper/CliDumper.php
index ab919e155850e..8cef9d3af49af 100644
--- a/src/Symfony/Component/VarDumper/Dumper/CliDumper.php
+++ b/src/Symfony/Component/VarDumper/Dumper/CliDumper.php
@@ -125,7 +125,7 @@ public function setDisplayOptions(array $displayOptions)
     /**
      * {@inheritdoc}
      */
-    public function dumpScalar(Cursor $cursor, string $type, $value)
+    public function dumpScalar(Cursor $cursor, string $type, string|int|float|bool|null $value)
     {
         $this->dumpKey($cursor);
 
@@ -267,7 +267,7 @@ public function dumpString(Cursor $cursor, string $str, bool $bin, int $cut)
     /**
      * {@inheritdoc}
      */
-    public function enterHash(Cursor $cursor, int $type, $class, bool $hasChild)
+    public function enterHash(Cursor $cursor, int $type, string|int|null $class, bool $hasChild)
     {
         if (null === $this->colors) {
             $this->colors = $this->supportsColors();
@@ -308,7 +308,7 @@ public function enterHash(Cursor $cursor, int $type, $class, bool $hasChild)
     /**
      * {@inheritdoc}
      */
-    public function leaveHash(Cursor $cursor, int $type, $class, bool $hasChild, int $cut)
+    public function leaveHash(Cursor $cursor, int $type, string|int|null $class, bool $hasChild, int $cut)
     {
         if (empty($cursor->attr['cut_hash'])) {
             $this->dumpEllipsis($cursor, $hasChild, $cut);
@@ -324,7 +324,7 @@ public function leaveHash(Cursor $cursor, int $type, $class, bool $hasChild, int
      * @param bool $hasChild When the dump of the hash has child item
      * @param int  $cut      The number of items the hash has been cut by
      */
-    protected function dumpEllipsis(Cursor $cursor, $hasChild, $cut)
+    protected function dumpEllipsis(Cursor $cursor, bool $hasChild, int $cut)
     {
         if ($cut) {
             $this->line .= ' …';
@@ -428,7 +428,7 @@ protected function dumpKey(Cursor $cursor)
      *
      * @return string The value with style decoration
      */
-    protected function style($style, $value, $attr = [])
+    protected function style(string $style, string $value, array $attr = [])
     {
         if (null === $this->colors) {
             $this->colors = $this->supportsColors();
@@ -576,10 +576,8 @@ protected function endValue(Cursor $cursor)
      *
      * Reference: Composer\XdebugHandler\Process::supportsColor
      * https://github.com/composer/xdebug-handler
-     *
-     * @param mixed $stream A CLI output stream
      */
-    private function hasColorSupport($stream): bool
+    private function hasColorSupport(mixed $stream): bool
     {
         if (!\is_resource($stream) || 'stream' !== get_resource_type($stream)) {
             return false;
diff --git a/src/Symfony/Component/VarDumper/Dumper/HtmlDumper.php b/src/Symfony/Component/VarDumper/Dumper/HtmlDumper.php
index 9bbd2d65abc68..9b6d0a34dbed5 100644
--- a/src/Symfony/Component/VarDumper/Dumper/HtmlDumper.php
+++ b/src/Symfony/Component/VarDumper/Dumper/HtmlDumper.php
@@ -116,21 +116,16 @@ public function setDisplayOptions(array $displayOptions)
 
     /**
      * Sets an HTML header that will be dumped once in the output stream.
-     *
-     * @param string $header An HTML string
      */
-    public function setDumpHeader($header)
+    public function setDumpHeader(string $header)
     {
         $this->dumpHeader = $header;
     }
 
     /**
      * Sets an HTML prefix and suffix that will encapse every single dump.
-     *
-     * @param string $prefix The prepended HTML string
-     * @param string $suffix The appended HTML string
      */
-    public function setDumpBoundaries($prefix, $suffix)
+    public function setDumpBoundaries(string $prefix, string $suffix)
     {
         $this->dumpPrefix = $prefix;
         $this->dumpSuffix = $suffix;
@@ -808,7 +803,7 @@ public function dumpString(Cursor $cursor, string $str, bool $bin, int $cut)
     /**
      * {@inheritdoc}
      */
-    public function enterHash(Cursor $cursor, int $type, $class, bool $hasChild)
+    public function enterHash(Cursor $cursor, int $type, string|int|null $class, bool $hasChild)
     {
         if (Cursor::HASH_OBJECT === $type) {
             $cursor->attr['depth'] = $cursor->depth;
@@ -839,7 +834,7 @@ public function enterHash(Cursor $cursor, int $type, $class, bool $hasChild)
     /**
      * {@inheritdoc}
      */
-    public function leaveHash(Cursor $cursor, int $type, $class, bool $hasChild, int $cut)
+    public function leaveHash(Cursor $cursor, int $type, string|int|null $class, bool $hasChild, int $cut)
     {
         $this->dumpEllipsis($cursor, $hasChild, $cut);
         if ($hasChild) {
@@ -851,7 +846,7 @@ public function leaveHash(Cursor $cursor, int $type, $class, bool $hasChild, int
     /**
      * {@inheritdoc}
      */
-    protected function style($style, $value, $attr = [])
+    protected function style(string $style, string $value, array $attr = [])
     {
         if ('' === $value) {
             return '';
diff --git a/src/Symfony/Component/VarDumper/Resources/functions/dump.php b/src/Symfony/Component/VarDumper/Resources/functions/dump.php
index a485d573a007a..ed94fe148c947 100644
--- a/src/Symfony/Component/VarDumper/Resources/functions/dump.php
+++ b/src/Symfony/Component/VarDumper/Resources/functions/dump.php
@@ -15,7 +15,7 @@
     /**
      * @author Nicolas Grekas <p@tchwork.com>
      */
-    function dump($var, ...$moreVars)
+    function dump(mixed $var, mixed ...$moreVars): mixed
     {
         VarDumper::dump($var);
 
@@ -32,7 +32,7 @@ function dump($var, ...$moreVars)
 }
 
 if (!function_exists('dd')) {
-    function dd(...$vars)
+    function dd(mixed ...$vars): void
     {
         foreach ($vars as $v) {
             VarDumper::dump($v);
diff --git a/src/Symfony/Component/VarDumper/Server/Connection.php b/src/Symfony/Component/VarDumper/Server/Connection.php
index d8be23587e764..ae4e76f7efdd3 100644
--- a/src/Symfony/Component/VarDumper/Server/Connection.php
+++ b/src/Symfony/Component/VarDumper/Server/Connection.php
@@ -78,7 +78,7 @@ public function write(Data $data): bool
         return false;
     }
 
-    private static function nullErrorHandler($t, $m)
+    private static function nullErrorHandler(int $t, string $m)
     {
         // no-op
     }
diff --git a/src/Symfony/Component/VarDumper/Test/VarDumperTestTrait.php b/src/Symfony/Component/VarDumper/Test/VarDumperTestTrait.php
index 33d60c020196b..ec18463252730 100644
--- a/src/Symfony/Component/VarDumper/Test/VarDumperTestTrait.php
+++ b/src/Symfony/Component/VarDumper/Test/VarDumperTestTrait.php
@@ -42,17 +42,17 @@ protected function tearDownVarDumper(): void
         $this->varDumperConfig['flags'] = null;
     }
 
-    public function assertDumpEquals($expected, $data, int $filter = 0, string $message = '')
+    public function assertDumpEquals(mixed $expected, mixed $data, int $filter = 0, string $message = '')
     {
         $this->assertSame($this->prepareExpectation($expected, $filter), $this->getDump($data, null, $filter), $message);
     }
 
-    public function assertDumpMatchesFormat($expected, $data, int $filter = 0, string $message = '')
+    public function assertDumpMatchesFormat(mixed $expected, mixed $data, int $filter = 0, string $message = '')
     {
         $this->assertStringMatchesFormat($this->prepareExpectation($expected, $filter), $this->getDump($data, null, $filter), $message);
     }
 
-    protected function getDump($data, $key = null, int $filter = 0): ?string
+    protected function getDump(mixed $data, string|int|null $key = null, int $filter = 0): ?string
     {
         if (null === $flags = $this->varDumperConfig['flags']) {
             $flags = getenv('DUMP_LIGHT_ARRAY') ? CliDumper::DUMP_LIGHT_ARRAY : 0;
@@ -73,7 +73,7 @@ protected function getDump($data, $key = null, int $filter = 0): ?string
         return rtrim($dumper->dump($data, true));
     }
 
-    private function prepareExpectation($expected, int $filter): string
+    private function prepareExpectation(mixed $expected, int $filter): string
     {
         if (!\is_string($expected)) {
             $expected = $this->getDump($expected, null, $filter);
diff --git a/src/Symfony/Component/VarDumper/VarDumper.php b/src/Symfony/Component/VarDumper/VarDumper.php
index b223e065106d2..e965d05e0e15f 100644
--- a/src/Symfony/Component/VarDumper/VarDumper.php
+++ b/src/Symfony/Component/VarDumper/VarDumper.php
@@ -34,7 +34,7 @@ class VarDumper
 {
     private static $handler;
 
-    public static function dump($var)
+    public static function dump(mixed $var)
     {
         if (null === self::$handler) {
             self::register();