diff --git a/.gitattributes b/.gitattributes
index 84c7add05..14c3c3594 100644
--- a/.gitattributes
+++ b/.gitattributes
@@ -1,4 +1,3 @@
 /Tests export-ignore
 /phpunit.xml.dist export-ignore
-/.gitattributes export-ignore
-/.gitignore export-ignore
+/.git* export-ignore
diff --git a/.github/PULL_REQUEST_TEMPLATE.md b/.github/PULL_REQUEST_TEMPLATE.md
new file mode 100644
index 000000000..4689c4dad
--- /dev/null
+++ b/.github/PULL_REQUEST_TEMPLATE.md
@@ -0,0 +1,8 @@
+Please do not submit any Pull Requests here. They will be closed.
+---
+
+Please submit your PR here instead:
+https://github.com/symfony/symfony
+
+This repository is what we call a "subtree split": a read-only subset of that main repository.
+We're looking forward to your PR there!
diff --git a/.github/workflows/close-pull-request.yml b/.github/workflows/close-pull-request.yml
new file mode 100644
index 000000000..e55b47817
--- /dev/null
+++ b/.github/workflows/close-pull-request.yml
@@ -0,0 +1,20 @@
+name: Close Pull Request
+
+on:
+  pull_request_target:
+    types: [opened]
+
+jobs:
+  run:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: superbrothers/close-pull-request@v3
+      with:
+        comment: |
+          Thanks for your Pull Request! We love contributions.
+
+          However, you should instead open your PR on the main repository:
+          https://github.com/symfony/symfony
+
+          This repository is what we call a "subtree split": a read-only subset of that main repository.
+          We're looking forward to your PR there!
diff --git a/Builder/ClassBuilder.php b/Builder/ClassBuilder.php
index 619ebd857..5ae8bda16 100644
--- a/Builder/ClassBuilder.php
+++ b/Builder/ClassBuilder.php
@@ -20,7 +20,6 @@
  */
 class ClassBuilder
 {
-    private string $namespace;
     private string $name;
 
     /** @var Property[] */
@@ -33,9 +32,10 @@ class ClassBuilder
     private array $implements = [];
     private bool $allowExtraKeys = false;
 
-    public function __construct(string $namespace, string $name)
-    {
-        $this->namespace = $namespace;
+    public function __construct(
+        private string $namespace,
+        string $name,
+    ) {
         $this->name = ucfirst($this->camelCase($name)).'Config';
     }
 
@@ -63,11 +63,11 @@ public function build(): string
                 }
                 unset($path[$key]);
             }
-            $require .= sprintf('require_once __DIR__.\DIRECTORY_SEPARATOR.\'%s\';', implode('\'.\DIRECTORY_SEPARATOR.\'', $path))."\n";
+            $require .= \sprintf('require_once __DIR__.\DIRECTORY_SEPARATOR.\'%s\';', implode('\'.\DIRECTORY_SEPARATOR.\'', $path))."\n";
         }
         $use = $require ? "\n" : '';
         foreach (array_keys($this->use) as $statement) {
-            $use .= sprintf('use %s;', $statement)."\n";
+            $use .= \sprintf('use %s;', $statement)."\n";
         }
 
         $implements = [] === $this->implements ? '' : 'implements '.implode(', ', $this->implements);
@@ -82,7 +82,7 @@ public function build(): string
             }
         }
 
-        $content = strtr('<?php
+        return strtr('<?php
 
 namespace NAMESPACE;
 
@@ -95,8 +95,6 @@ class CLASS IMPLEMENTS
 BODY
 }
 ', ['NAMESPACE' => $this->namespace, 'REQUIRE' => $require, 'USE' => $use, 'CLASS' => $this->getName(), 'IMPLEMENTS' => $implements, 'BODY' => $body]);
-
-        return $content;
     }
 
     public function addRequire(self $class): void
@@ -126,8 +124,8 @@ public function addProperty(string $name, ?string $classType = null, ?string $de
             $property->setType($classType);
         }
         $this->properties[] = $property;
-        $defaultValue = null !== $defaultValue ? sprintf(' = %s', $defaultValue) : '';
-        $property->setContent(sprintf('private $%s%s;', $property->getName(), $defaultValue));
+        $defaultValue = null !== $defaultValue ? \sprintf(' = %s', $defaultValue) : '';
+        $property->setContent(\sprintf('private $%s%s;', $property->getName(), $defaultValue));
 
         return $property;
     }
diff --git a/Builder/ConfigBuilderGenerator.php b/Builder/ConfigBuilderGenerator.php
index d43d814eb..08e91c2d1 100644
--- a/Builder/ConfigBuilderGenerator.php
+++ b/Builder/ConfigBuilderGenerator.php
@@ -37,11 +37,10 @@ class ConfigBuilderGenerator implements ConfigBuilderGeneratorInterface
      * @var ClassBuilder[]
      */
     private array $classes = [];
-    private string $outputDir;
 
-    public function __construct(string $outputDir)
-    {
-        $this->outputDir = $outputDir;
+    public function __construct(
+        private string $outputDir,
+    ) {
     }
 
     /**
@@ -115,7 +114,7 @@ private function buildNode(NodeInterface $node, ClassBuilder $class, string $nam
                 $child instanceof PrototypedArrayNode => $this->handlePrototypedArrayNode($child, $class, $namespace),
                 $child instanceof VariableNode => $this->handleVariableNode($child, $class),
                 $child instanceof ArrayNode => $this->handleArrayNode($child, $class, $namespace),
-                default => throw new \RuntimeException(sprintf('Unknown node "%s".', $child::class)),
+                default => throw new \RuntimeException(\sprintf('Unknown node "%s".', $child::class)),
             };
         }
     }
@@ -130,9 +129,9 @@ private function handleArrayNode(ArrayNode $node, ClassBuilder $class, string $n
         $hasNormalizationClosures = $this->hasNormalizationClosures($node);
         $comment = $this->getComment($node);
         if ($hasNormalizationClosures) {
-            $comment = sprintf(" * @template TValue\n * @param TValue \$value\n%s", $comment);
-            $comment .= sprintf(' * @return %s|$this'."\n", $childClass->getFqcn());
-            $comment .= sprintf(' * @psalm-return (TValue is array ? %s : static)'."\n ", $childClass->getFqcn());
+            $comment = \sprintf(" * @template TValue\n * @param TValue \$value\n%s", $comment);
+            $comment .= \sprintf(' * @return %s|$this'."\n", $childClass->getFqcn());
+            $comment .= \sprintf(' * @psalm-return (TValue is array ? %s : static)'."\n ", $childClass->getFqcn());
         }
         if ('' !== $comment) {
             $comment = "/**\n$comment*/\n";
@@ -282,9 +281,9 @@ public function NAME(string $VAR, TYPE $VALUE): static
 
         $comment = $this->getComment($node);
         if ($hasNormalizationClosures) {
-            $comment = sprintf(" * @template TValue\n * @param TValue \$value\n%s", $comment);
-            $comment .= sprintf(' * @return %s|$this'."\n", $childClass->getFqcn());
-            $comment .= sprintf(' * @psalm-return (TValue is array ? %s : static)'."\n ", $childClass->getFqcn());
+            $comment = \sprintf(" * @template TValue\n * @param TValue \$value\n%s", $comment);
+            $comment .= \sprintf(' * @return %s|$this'."\n", $childClass->getFqcn());
+            $comment .= \sprintf(' * @psalm-return (TValue is array ? %s : static)'."\n ", $childClass->getFqcn());
         }
         if ('' !== $comment) {
             $comment = "/**\n$comment*/\n";
@@ -426,7 +425,7 @@ private function getComment(BaseNode $node): string
             }
 
             if ($node instanceof EnumNode) {
-                $comment .= sprintf(' * @param ParamConfigurator|%s $value', implode('|', array_unique(array_map(fn ($a) => !$a instanceof \UnitEnum ? var_export($a, true) : '\\'.ltrim(var_export($a, true), '\\'), $node->getValues()))))."\n";
+                $comment .= \sprintf(' * @param ParamConfigurator|%s $value', implode('|', array_unique(array_map(fn ($a) => !$a instanceof \UnitEnum ? var_export($a, true) : '\\'.ltrim(var_export($a, true), '\\'), $node->getValues()))))."\n";
             } else {
                 $parameterTypes = $this->getParameterTypes($node);
                 $comment .= ' * @param ParamConfigurator|'.implode('|', $parameterTypes).' $value'."\n";
@@ -579,7 +578,7 @@ public function NAME(string $key, mixed $value): static
 
     private function getSubNamespace(ClassBuilder $rootClass): string
     {
-        return sprintf('%s\\%s', $rootClass->getNamespace(), substr($rootClass->getName(), 0, -6));
+        return \sprintf('%s\\%s', $rootClass->getNamespace(), substr($rootClass->getName(), 0, -6));
     }
 
     private function hasNormalizationClosures(NodeInterface $node): bool
diff --git a/Builder/Method.php b/Builder/Method.php
index c97c98649..8fba068a9 100644
--- a/Builder/Method.php
+++ b/Builder/Method.php
@@ -20,11 +20,9 @@
  */
 class Method
 {
-    private string $content;
-
-    public function __construct(string $content)
-    {
-        $this->content = $content;
+    public function __construct(
+        private string $content,
+    ) {
     }
 
     public function getContent(): string
diff --git a/Builder/Property.php b/Builder/Property.php
index cf2f8d549..ede5351c7 100644
--- a/Builder/Property.php
+++ b/Builder/Property.php
@@ -20,17 +20,15 @@
  */
 class Property
 {
-    private string $name;
-    private string $originalName;
     private bool $array = false;
     private bool $scalarsAllowed = false;
     private ?string $type = null;
     private ?string $content = null;
 
-    public function __construct(string $originalName, string $name)
-    {
-        $this->name = $name;
-        $this->originalName = $originalName;
+    public function __construct(
+        private string $originalName,
+        private string $name,
+    ) {
     }
 
     public function getName(): string
diff --git a/CHANGELOG.md b/CHANGELOG.md
index 094d5abba..e38639e4d 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -1,6 +1,28 @@
 CHANGELOG
 =========
 
+7.2
+---
+
+ * Add `#[WhenNot]` attribute to prevent service from being registered in a specific environment
+ * Generate a meta file in JSON format for resource tracking
+ * Add `SkippingResourceChecker`
+ * Add support for `defaultNull()` on `BooleanNode`
+ * Add `StringNode` and `StringNodeDefinition`
+ * Add `ArrayNodeDefinition::stringPrototype()` method
+ * Add `NodeBuilder::stringNode()` method
+
+7.1
+---
+
+ * Allow custom meta location in `ResourceCheckerConfigCache`
+ * Allow custom meta location in `ConfigCache`
+
+7.0
+---
+
+ * Require explicit argument when calling `NodeBuilder::setParent()`
+
 6.3
 ---
 
diff --git a/ConfigCache.php b/ConfigCache.php
index 89519417d..400b6162c 100644
--- a/ConfigCache.php
+++ b/ConfigCache.php
@@ -11,7 +11,9 @@
 
 namespace Symfony\Component\Config;
 
+use Symfony\Component\Config\Resource\ResourceInterface;
 use Symfony\Component\Config\Resource\SelfCheckingResourceChecker;
+use Symfony\Component\Config\Resource\SkippingResourceChecker;
 
 /**
  * ConfigCache caches arbitrary content in files on disk.
@@ -25,22 +27,27 @@
  */
 class ConfigCache extends ResourceCheckerConfigCache
 {
-    private bool $debug;
-
     /**
-     * @param string $file  The absolute cache path
-     * @param bool   $debug Whether debugging is enabled or not
+     * @param string                                 $file                 The absolute cache path
+     * @param bool                                   $debug                Whether debugging is enabled or not
+     * @param string|null                            $metaFile             The absolute path to the meta file
+     * @param class-string<ResourceInterface>[]|null $skippedResourceTypes
      */
-    public function __construct(string $file, bool $debug)
-    {
-        $this->debug = $debug;
-
+    public function __construct(
+        string $file,
+        private bool $debug,
+        ?string $metaFile = null,
+        array|null $skippedResourceTypes = null,
+    ) {
         $checkers = [];
-        if (true === $this->debug) {
-            $checkers = [new SelfCheckingResourceChecker()];
+        if ($this->debug) {
+            if (null !== $skippedResourceTypes) {
+                $checkers[] = new SkippingResourceChecker($skippedResourceTypes);
+            }
+            $checkers[] = new SelfCheckingResourceChecker();
         }
 
-        parent::__construct($file, $checkers);
+        parent::__construct($file, $checkers, $metaFile);
     }
 
     /**
diff --git a/ConfigCacheFactory.php b/ConfigCacheFactory.php
index 39adad1e1..27a18e751 100644
--- a/ConfigCacheFactory.php
+++ b/ConfigCacheFactory.php
@@ -22,14 +22,12 @@
  */
 class ConfigCacheFactory implements ConfigCacheFactoryInterface
 {
-    private bool $debug;
-
     /**
      * @param bool $debug The debug flag to pass to ConfigCache
      */
-    public function __construct(bool $debug)
-    {
-        $this->debug = $debug;
+    public function __construct(
+        private bool $debug,
+    ) {
     }
 
     public function cache(string $file, callable $callback): ConfigCacheInterface
diff --git a/ConfigCacheInterface.php b/ConfigCacheInterface.php
index f8d270634..7b9d38897 100644
--- a/ConfigCacheInterface.php
+++ b/ConfigCacheInterface.php
@@ -39,9 +39,7 @@ public function isFresh(): bool;
      * @param string                   $content  The content to write into the cache
      * @param ResourceInterface[]|null $metadata An array of ResourceInterface instances
      *
-     * @return void
-     *
      * @throws \RuntimeException When the cache file cannot be written
      */
-    public function write(string $content, ?array $metadata = null);
+    public function write(string $content, ?array $metadata = null): void;
 }
diff --git a/Definition/ArrayNode.php b/Definition/ArrayNode.php
index 1448220cd..5301b7243 100644
--- a/Definition/ArrayNode.php
+++ b/Definition/ArrayNode.php
@@ -22,20 +22,17 @@
  */
 class ArrayNode extends BaseNode implements PrototypeNodeInterface
 {
-    protected $xmlRemappings = [];
-    protected $children = [];
-    protected $allowFalse = false;
-    protected $allowNewKeys = true;
-    protected $addIfNotSet = false;
-    protected $performDeepMerging = true;
-    protected $ignoreExtraKeys = false;
-    protected $removeExtraKeys = true;
-    protected $normalizeKeys = true;
-
-    /**
-     * @return void
-     */
-    public function setNormalizeKeys(bool $normalizeKeys)
+    protected array $xmlRemappings = [];
+    protected array $children = [];
+    protected bool $allowFalse = false;
+    protected bool $allowNewKeys = true;
+    protected bool $addIfNotSet = false;
+    protected bool $performDeepMerging = true;
+    protected bool $ignoreExtraKeys = false;
+    protected bool $removeExtraKeys = true;
+    protected bool $normalizeKeys = true;
+
+    public function setNormalizeKeys(bool $normalizeKeys): void
     {
         $this->normalizeKeys = $normalizeKeys;
     }
@@ -80,10 +77,8 @@ public function getChildren(): array
      * Sets the xml remappings that should be performed.
      *
      * @param array $remappings An array of the form [[string, string]]
-     *
-     * @return void
      */
-    public function setXmlRemappings(array $remappings)
+    public function setXmlRemappings(array $remappings): void
     {
         $this->xmlRemappings = $remappings;
     }
@@ -101,40 +96,32 @@ public function getXmlRemappings(): array
     /**
      * Sets whether to add default values for this array if it has not been
      * defined in any of the configuration files.
-     *
-     * @return void
      */
-    public function setAddIfNotSet(bool $boolean)
+    public function setAddIfNotSet(bool $boolean): void
     {
         $this->addIfNotSet = $boolean;
     }
 
     /**
      * Sets whether false is allowed as value indicating that the array should be unset.
-     *
-     * @return void
      */
-    public function setAllowFalse(bool $allow)
+    public function setAllowFalse(bool $allow): void
     {
         $this->allowFalse = $allow;
     }
 
     /**
      * Sets whether new keys can be defined in subsequent configurations.
-     *
-     * @return void
      */
-    public function setAllowNewKeys(bool $allow)
+    public function setAllowNewKeys(bool $allow): void
     {
         $this->allowNewKeys = $allow;
     }
 
     /**
      * Sets if deep merging should occur.
-     *
-     * @return void
      */
-    public function setPerformDeepMerging(bool $boolean)
+    public function setPerformDeepMerging(bool $boolean): void
     {
         $this->performDeepMerging = $boolean;
     }
@@ -144,10 +131,8 @@ public function setPerformDeepMerging(bool $boolean)
      *
      * @param bool $boolean To allow extra keys
      * @param bool $remove  To remove extra keys
-     *
-     * @return void
      */
-    public function setIgnoreExtraKeys(bool $boolean, bool $remove = true)
+    public function setIgnoreExtraKeys(bool $boolean, bool $remove = true): void
     {
         $this->ignoreExtraKeys = $boolean;
         $this->removeExtraKeys = $this->ignoreExtraKeys && $remove;
@@ -161,10 +146,7 @@ public function shouldIgnoreExtraKeys(): bool
         return $this->ignoreExtraKeys;
     }
 
-    /**
-     * @return void
-     */
-    public function setName(string $name)
+    public function setName(string $name): void
     {
         $this->name = $name;
     }
@@ -177,7 +159,7 @@ public function hasDefaultValue(): bool
     public function getDefaultValue(): mixed
     {
         if (!$this->hasDefaultValue()) {
-            throw new \RuntimeException(sprintf('The node at path "%s" has no default value.', $this->getPath()));
+            throw new \RuntimeException(\sprintf('The node at path "%s" has no default value.', $this->getPath()));
         }
 
         $defaults = [];
@@ -193,19 +175,17 @@ public function getDefaultValue(): mixed
     /**
      * Adds a child node.
      *
-     * @return void
-     *
      * @throws \InvalidArgumentException when the child node has no name
      * @throws \InvalidArgumentException when the child node's name is not unique
      */
-    public function addChild(NodeInterface $node)
+    public function addChild(NodeInterface $node): void
     {
         $name = $node->getName();
         if ('' === $name) {
             throw new \InvalidArgumentException('Child nodes must be named.');
         }
         if (isset($this->children[$name])) {
-            throw new \InvalidArgumentException(sprintf('A child node named "%s" already exists.', $name));
+            throw new \InvalidArgumentException(\sprintf('A child node named "%s" already exists.', $name));
         }
 
         $this->children[$name] = $node;
@@ -218,15 +198,15 @@ public function addChild(NodeInterface $node)
     protected function finalizeValue(mixed $value): mixed
     {
         if (false === $value) {
-            throw new UnsetKeyException(sprintf('Unsetting key for path "%s", value: %s.', $this->getPath(), json_encode($value)));
+            throw new UnsetKeyException(\sprintf('Unsetting key for path "%s", value: false.', $this->getPath()));
         }
 
         foreach ($this->children as $name => $child) {
             if (!\array_key_exists($name, $value)) {
                 if ($child->isRequired()) {
-                    $message = sprintf('The child config "%s" under "%s" must be configured', $name, $this->getPath());
+                    $message = \sprintf('The child config "%s" under "%s" must be configured', $name, $this->getPath());
                     if ($child->getInfo()) {
-                        $message .= sprintf(': %s', $child->getInfo());
+                        $message .= \sprintf(': %s', $child->getInfo());
                     } else {
                         $message .= '.';
                     }
@@ -258,13 +238,10 @@ protected function finalizeValue(mixed $value): mixed
         return $value;
     }
 
-    /**
-     * @return void
-     */
-    protected function validateType(mixed $value)
+    protected function validateType(mixed $value): void
     {
         if (!\is_array($value) && (!$this->allowFalse || false !== $value)) {
-            $ex = new InvalidTypeException(sprintf('Invalid type for path "%s". Expected "array", but got "%s"', $this->getPath(), get_debug_type($value)));
+            $ex = new InvalidTypeException(\sprintf('Invalid type for path "%s". Expected "array", but got "%s"', $this->getPath(), get_debug_type($value)));
             if ($hint = $this->getInfo()) {
                 $ex->addHint($hint);
             }
@@ -315,13 +292,13 @@ protected function normalizeValue(mixed $value): mixed
                 }
             }
 
-            $msg = sprintf('Unrecognized option%s "%s" under "%s"', 1 === \count($value) ? '' : 's', implode(', ', array_keys($value)), $this->getPath());
+            $msg = \sprintf('Unrecognized option%s "%s" under "%s"', 1 === \count($value) ? '' : 's', implode(', ', array_keys($value)), $this->getPath());
 
             if (\count($guesses)) {
                 asort($guesses);
-                $msg .= sprintf('. Did you mean "%s"?', implode('", "', array_keys($guesses)));
+                $msg .= \sprintf('. Did you mean "%s"?', implode('", "', array_keys($guesses)));
             } else {
-                $msg .= sprintf('. Available option%s %s "%s".', 1 === \count($proposals) ? '' : 's', 1 === \count($proposals) ? 'is' : 'are', implode('", "', $proposals));
+                $msg .= \sprintf('. Available option%s %s "%s".', 1 === \count($proposals) ? '' : 's', 1 === \count($proposals) ? 'is' : 'are', implode('", "', $proposals));
             }
 
             $ex = new InvalidConfigurationException($msg);
@@ -370,7 +347,7 @@ protected function mergeValues(mixed $leftSide, mixed $rightSide): mixed
             // no conflict
             if (!\array_key_exists($k, $leftSide)) {
                 if (!$this->allowNewKeys) {
-                    $ex = new InvalidConfigurationException(sprintf('You are not allowed to define new elements for path "%s". Please define all elements for this path in one config file. If you are trying to overwrite an element, make sure you redefine it with the same name.', $this->getPath()));
+                    $ex = new InvalidConfigurationException(\sprintf('You are not allowed to define new elements for path "%s". Please define all elements for this path in one config file. If you are trying to overwrite an element, make sure you redefine it with the same name.', $this->getPath()));
                     $ex->setPath($this->getPath());
 
                     throw $ex;
diff --git a/Definition/BaseNode.php b/Definition/BaseNode.php
index 6e2a19227..9cfd69239 100644
--- a/Definition/BaseNode.php
+++ b/Definition/BaseNode.php
@@ -29,32 +29,31 @@ abstract class BaseNode implements NodeInterface
     private static array $placeholderUniquePrefixes = [];
     private static array $placeholders = [];
 
-    protected $name;
-    protected $parent;
-    protected $normalizationClosures = [];
-    protected $normalizedTypes = [];
-    protected $finalValidationClosures = [];
-    protected $allowOverwrite = true;
-    protected $required = false;
-    protected $deprecation = [];
-    protected $equivalentValues = [];
-    protected $attributes = [];
-    protected $pathSeparator;
+    protected string $name;
+    protected array $normalizationClosures = [];
+    protected array $normalizedTypes = [];
+    protected array $finalValidationClosures = [];
+    protected bool $allowOverwrite = true;
+    protected bool $required = false;
+    protected array $deprecation = [];
+    protected array $equivalentValues = [];
+    protected array $attributes = [];
 
     private mixed $handlingPlaceholder = null;
 
     /**
      * @throws \InvalidArgumentException if the name contains a period
      */
-    public function __construct(?string $name, ?NodeInterface $parent = null, string $pathSeparator = self::DEFAULT_PATH_SEPARATOR)
-    {
+    public function __construct(
+        ?string $name,
+        protected ?NodeInterface $parent = null,
+        protected string $pathSeparator = self::DEFAULT_PATH_SEPARATOR,
+    ) {
         if (str_contains($name = (string) $name, $pathSeparator)) {
             throw new \InvalidArgumentException('The name must not contain ".'.$pathSeparator.'".');
         }
 
         $this->name = $name;
-        $this->parent = $parent;
-        $this->pathSeparator = $pathSeparator;
     }
 
     /**
@@ -98,10 +97,7 @@ public static function resetPlaceholders(): void
         self::$placeholders = [];
     }
 
-    /**
-     * @return void
-     */
-    public function setAttribute(string $key, mixed $value)
+    public function setAttribute(string $key, mixed $value): void
     {
         $this->attributes[$key] = $value;
     }
@@ -121,28 +117,20 @@ public function getAttributes(): array
         return $this->attributes;
     }
 
-    /**
-     * @return void
-     */
-    public function setAttributes(array $attributes)
+    public function setAttributes(array $attributes): void
     {
         $this->attributes = $attributes;
     }
 
-    /**
-     * @return void
-     */
-    public function removeAttribute(string $key)
+    public function removeAttribute(string $key): void
     {
         unset($this->attributes[$key]);
     }
 
     /**
      * Sets an info message.
-     *
-     * @return void
      */
-    public function setInfo(string $info)
+    public function setInfo(string $info): void
     {
         $this->setAttribute('info', $info);
     }
@@ -157,10 +145,8 @@ public function getInfo(): ?string
 
     /**
      * Sets the example configuration for this node.
-     *
-     * @return void
      */
-    public function setExample(string|array $example)
+    public function setExample(string|array $example): void
     {
         $this->setAttribute('example', $example);
     }
@@ -175,20 +161,16 @@ public function getExample(): string|array|null
 
     /**
      * Adds an equivalent value.
-     *
-     * @return void
      */
-    public function addEquivalentValue(mixed $originalValue, mixed $equivalentValue)
+    public function addEquivalentValue(mixed $originalValue, mixed $equivalentValue): void
     {
         $this->equivalentValues[] = [$originalValue, $equivalentValue];
     }
 
     /**
      * Set this node as required.
-     *
-     * @return void
      */
-    public function setRequired(bool $boolean)
+    public function setRequired(bool $boolean): void
     {
         $this->required = $boolean;
     }
@@ -202,10 +184,8 @@ public function setRequired(bool $boolean)
      * @param string $package The name of the composer package that is triggering the deprecation
      * @param string $version The version of the package that introduced the deprecation
      * @param string $message the deprecation message to use
-     *
-     * @return void
      */
-    public function setDeprecated(string $package, string $version, string $message = 'The child node "%node%" at path "%path%" is deprecated.')
+    public function setDeprecated(string $package, string $version, string $message = 'The child node "%node%" at path "%path%" is deprecated.'): void
     {
         $this->deprecation = [
             'package' => $package,
@@ -216,10 +196,8 @@ public function setDeprecated(string $package, string $version, string $message
 
     /**
      * Sets if this node can be overridden.
-     *
-     * @return void
      */
-    public function setAllowOverwrite(bool $allow)
+    public function setAllowOverwrite(bool $allow): void
     {
         $this->allowOverwrite = $allow;
     }
@@ -228,10 +206,8 @@ public function setAllowOverwrite(bool $allow)
      * Sets the closures used for normalization.
      *
      * @param \Closure[] $closures An array of Closures used for normalization
-     *
-     * @return void
      */
-    public function setNormalizationClosures(array $closures)
+    public function setNormalizationClosures(array $closures): void
     {
         $this->normalizationClosures = $closures;
     }
@@ -240,10 +216,8 @@ public function setNormalizationClosures(array $closures)
      * Sets the list of types supported by normalization.
      *
      * see ExprBuilder::TYPE_* constants.
-     *
-     * @return void
      */
-    public function setNormalizedTypes(array $types)
+    public function setNormalizedTypes(array $types): void
     {
         $this->normalizedTypes = $types;
     }
@@ -262,10 +236,8 @@ public function getNormalizedTypes(): array
      * Sets the closures used for final validation.
      *
      * @param \Closure[] $closures An array of Closures used for final validation
-     *
-     * @return void
      */
-    public function setFinalValidationClosures(array $closures)
+    public function setFinalValidationClosures(array $closures): void
     {
         $this->finalValidationClosures = $closures;
     }
@@ -313,7 +285,7 @@ public function getPath(): string
     final public function merge(mixed $leftSide, mixed $rightSide): mixed
     {
         if (!$this->allowOverwrite) {
-            throw new ForbiddenOverwriteException(sprintf('Configuration path "%s" cannot be overwritten. You have to define all options for this path, and any of its sub-paths in one configuration section.', $this->getPath()));
+            throw new ForbiddenOverwriteException(\sprintf('Configuration path "%s" cannot be overwritten. You have to define all options for this path, and any of its sub-paths in one configuration section.', $this->getPath()));
         }
 
         if ($leftSide !== $leftPlaceholders = self::resolvePlaceholderValue($leftSide)) {
@@ -432,7 +404,7 @@ final public function finalize(mixed $value): mixed
 
                 throw $e;
             } catch (\Exception $e) {
-                throw new InvalidConfigurationException(sprintf('Invalid configuration for path "%s": ', $this->getPath()).$e->getMessage(), $e->getCode(), $e);
+                throw new InvalidConfigurationException(\sprintf('Invalid configuration for path "%s": ', $this->getPath()).$e->getMessage(), $e->getCode(), $e);
             }
         }
 
@@ -442,11 +414,9 @@ final public function finalize(mixed $value): mixed
     /**
      * Validates the type of a Node.
      *
-     * @return void
-     *
      * @throws InvalidTypeException when the value is invalid
      */
-    abstract protected function validateType(mixed $value);
+    abstract protected function validateType(mixed $value): void;
 
     /**
      * Normalizes the value.
@@ -507,7 +477,7 @@ private static function resolvePlaceholderValue(mixed $value): mixed
     private function doValidateType(mixed $value): void
     {
         if (null !== $this->handlingPlaceholder && !$this->allowPlaceholders()) {
-            $e = new InvalidTypeException(sprintf('A dynamic value is not compatible with a "%s" node type at path "%s".', static::class, $this->getPath()));
+            $e = new InvalidTypeException(\sprintf('A dynamic value is not compatible with a "%s" node type at path "%s".', static::class, $this->getPath()));
             $e->setPath($this->getPath());
 
             throw $e;
@@ -523,7 +493,7 @@ private function doValidateType(mixed $value): void
         $validTypes = $this->getValidPlaceholderTypes();
 
         if ($validTypes && array_diff($knownTypes, $validTypes)) {
-            $e = new InvalidTypeException(sprintf(
+            $e = new InvalidTypeException(\sprintf(
                 'Invalid type for path "%s". Expected %s, but got %s.',
                 $this->getPath(),
                 1 === \count($validTypes) ? '"'.reset($validTypes).'"' : 'one of "'.implode('", "', $validTypes).'"',
diff --git a/Definition/BooleanNode.php b/Definition/BooleanNode.php
index 7ec903cd6..b4ed0f0eb 100644
--- a/Definition/BooleanNode.php
+++ b/Definition/BooleanNode.php
@@ -20,13 +20,23 @@
  */
 class BooleanNode extends ScalarNode
 {
-    /**
-     * @return void
-     */
-    protected function validateType(mixed $value)
+    public function __construct(
+        ?string $name,
+        ?NodeInterface $parent = null,
+        string $pathSeparator = self::DEFAULT_PATH_SEPARATOR,
+        private bool $nullable = false,
+    ) {
+        parent::__construct($name, $parent, $pathSeparator);
+    }
+
+    protected function validateType(mixed $value): void
     {
         if (!\is_bool($value)) {
-            $ex = new InvalidTypeException(sprintf('Invalid type for path "%s". Expected "bool", but got "%s".', $this->getPath(), get_debug_type($value)));
+            if (null === $value && $this->nullable) {
+                return;
+            }
+
+            $ex = new InvalidTypeException(\sprintf('Invalid type for path "%s". Expected "bool%s", but got "%s".', $this->getPath(), $this->nullable ? '" or "null' : '', get_debug_type($value)));
             if ($hint = $this->getInfo()) {
                 $ex->addHint($hint);
             }
diff --git a/Definition/Builder/ArrayNodeDefinition.php b/Definition/Builder/ArrayNodeDefinition.php
index 7a82334ee..6b75ba137 100644
--- a/Definition/Builder/ArrayNodeDefinition.php
+++ b/Definition/Builder/ArrayNodeDefinition.php
@@ -23,19 +23,19 @@
  */
 class ArrayNodeDefinition extends NodeDefinition implements ParentNodeDefinitionInterface
 {
-    protected $performDeepMerging = true;
-    protected $ignoreExtraKeys = false;
-    protected $removeExtraKeys = true;
-    protected $children = [];
-    protected $prototype;
-    protected $atLeastOne = false;
-    protected $allowNewKeys = true;
-    protected $key;
-    protected $removeKeyItem;
-    protected $addDefaults = false;
-    protected $addDefaultChildren = false;
-    protected $nodeBuilder;
-    protected $normalizeKeys = true;
+    protected bool $performDeepMerging = true;
+    protected bool $ignoreExtraKeys = false;
+    protected bool $removeExtraKeys = true;
+    protected array $children = [];
+    protected NodeDefinition $prototype;
+    protected bool $atLeastOne = false;
+    protected bool $allowNewKeys = true;
+    protected ?string $key = null;
+    protected bool $removeKeyItem = false;
+    protected bool $addDefaults = false;
+    protected int|string|array|false|null $addDefaultChildren = false;
+    protected NodeBuilder $nodeBuilder;
+    protected bool $normalizeKeys = true;
 
     public function __construct(?string $name, ?NodeParentInterface $parent = null)
     {
@@ -45,10 +45,7 @@ public function __construct(?string $name, ?NodeParentInterface $parent = null)
         $this->trueEquivalent = [];
     }
 
-    /**
-     * @return void
-     */
-    public function setBuilder(NodeBuilder $builder)
+    public function setBuilder(NodeBuilder $builder): void
     {
         $this->nodeBuilder = $builder;
     }
@@ -76,6 +73,11 @@ public function scalarPrototype(): ScalarNodeDefinition
         return $this->prototype('scalar');
     }
 
+    public function stringPrototype(): StringNodeDefinition
+    {
+        return $this->prototype('string');
+    }
+
     public function booleanPrototype(): BooleanNodeDefinition
     {
         return $this->prototype('boolean');
@@ -374,7 +376,7 @@ protected function createNode(): NodeInterface
 
             if ($this->default) {
                 if (!\is_array($this->defaultValue)) {
-                    throw new \InvalidArgumentException(sprintf('%s: the default value of an array node has to be an array.', $node->getPath()));
+                    throw new \InvalidArgumentException(\sprintf('%s: the default value of an array node has to be an array.', $node->getPath()));
                 }
 
                 $node->setDefaultValue($this->defaultValue);
@@ -425,61 +427,57 @@ protected function createNode(): NodeInterface
     /**
      * Validate the configuration of a concrete node.
      *
-     * @return void
-     *
      * @throws InvalidDefinitionException
      */
-    protected function validateConcreteNode(ArrayNode $node)
+    protected function validateConcreteNode(ArrayNode $node): void
     {
         $path = $node->getPath();
 
         if (null !== $this->key) {
-            throw new InvalidDefinitionException(sprintf('->useAttributeAsKey() is not applicable to concrete nodes at path "%s".', $path));
+            throw new InvalidDefinitionException(\sprintf('->useAttributeAsKey() is not applicable to concrete nodes at path "%s".', $path));
         }
 
         if (false === $this->allowEmptyValue) {
-            throw new InvalidDefinitionException(sprintf('->cannotBeEmpty() is not applicable to concrete nodes at path "%s".', $path));
+            throw new InvalidDefinitionException(\sprintf('->cannotBeEmpty() is not applicable to concrete nodes at path "%s".', $path));
         }
 
         if (true === $this->atLeastOne) {
-            throw new InvalidDefinitionException(sprintf('->requiresAtLeastOneElement() is not applicable to concrete nodes at path "%s".', $path));
+            throw new InvalidDefinitionException(\sprintf('->requiresAtLeastOneElement() is not applicable to concrete nodes at path "%s".', $path));
         }
 
         if ($this->default) {
-            throw new InvalidDefinitionException(sprintf('->defaultValue() is not applicable to concrete nodes at path "%s".', $path));
+            throw new InvalidDefinitionException(\sprintf('->defaultValue() is not applicable to concrete nodes at path "%s".', $path));
         }
 
         if (false !== $this->addDefaultChildren) {
-            throw new InvalidDefinitionException(sprintf('->addDefaultChildrenIfNoneSet() is not applicable to concrete nodes at path "%s".', $path));
+            throw new InvalidDefinitionException(\sprintf('->addDefaultChildrenIfNoneSet() is not applicable to concrete nodes at path "%s".', $path));
         }
     }
 
     /**
      * Validate the configuration of a prototype node.
      *
-     * @return void
-     *
      * @throws InvalidDefinitionException
      */
-    protected function validatePrototypeNode(PrototypedArrayNode $node)
+    protected function validatePrototypeNode(PrototypedArrayNode $node): void
     {
         $path = $node->getPath();
 
         if ($this->addDefaults) {
-            throw new InvalidDefinitionException(sprintf('->addDefaultsIfNotSet() is not applicable to prototype nodes at path "%s".', $path));
+            throw new InvalidDefinitionException(\sprintf('->addDefaultsIfNotSet() is not applicable to prototype nodes at path "%s".', $path));
         }
 
         if (false !== $this->addDefaultChildren) {
             if ($this->default) {
-                throw new InvalidDefinitionException(sprintf('A default value and default children might not be used together at path "%s".', $path));
+                throw new InvalidDefinitionException(\sprintf('A default value and default children might not be used together at path "%s".', $path));
             }
 
             if (null !== $this->key && (null === $this->addDefaultChildren || \is_int($this->addDefaultChildren) && $this->addDefaultChildren > 0)) {
-                throw new InvalidDefinitionException(sprintf('->addDefaultChildrenIfNoneSet() should set default children names as ->useAttributeAsKey() is used at path "%s".', $path));
+                throw new InvalidDefinitionException(\sprintf('->addDefaultChildrenIfNoneSet() should set default children names as ->useAttributeAsKey() is used at path "%s".', $path));
             }
 
             if (null === $this->key && (\is_string($this->addDefaultChildren) || \is_array($this->addDefaultChildren))) {
-                throw new InvalidDefinitionException(sprintf('->addDefaultChildrenIfNoneSet() might not set default children names as ->useAttributeAsKey() is not used at path "%s".', $path));
+                throw new InvalidDefinitionException(\sprintf('->addDefaultChildrenIfNoneSet() might not set default children names as ->useAttributeAsKey() is not used at path "%s".', $path));
             }
         }
     }
@@ -504,7 +502,7 @@ public function find(string $nodePath): NodeDefinition
             : substr($nodePath, 0, $pathSeparatorPos);
 
         if (null === $node = ($this->children[$firstPathSegment] ?? null)) {
-            throw new \RuntimeException(sprintf('Node with name "%s" does not exist in the current node "%s".', $firstPathSegment, $this->name));
+            throw new \RuntimeException(\sprintf('Node with name "%s" does not exist in the current node "%s".', $firstPathSegment, $this->name));
         }
 
         if (false === $pathSeparatorPos) {
diff --git a/Definition/Builder/BooleanNodeDefinition.php b/Definition/Builder/BooleanNodeDefinition.php
index 15e63961a..bc03c9c94 100644
--- a/Definition/Builder/BooleanNodeDefinition.php
+++ b/Definition/Builder/BooleanNodeDefinition.php
@@ -33,7 +33,7 @@ public function __construct(?string $name, ?NodeParentInterface $parent = null)
      */
     protected function instantiateNode(): BooleanNode
     {
-        return new BooleanNode($this->name, $this->parent, $this->pathSeparator);
+        return new BooleanNode($this->name, $this->parent, $this->pathSeparator, null === $this->nullEquivalent);
     }
 
     /**
@@ -43,4 +43,20 @@ public function cannotBeEmpty(): static
     {
         throw new InvalidDefinitionException('->cannotBeEmpty() is not applicable to BooleanNodeDefinition.');
     }
+
+    public function defaultNull(): static
+    {
+        $this->nullEquivalent = null;
+
+        return parent::defaultNull();
+    }
+
+    public function defaultValue(mixed $value): static
+    {
+        if (null === $value) {
+            $this->nullEquivalent = null;
+        }
+
+        return parent::defaultValue($value);
+    }
 }
diff --git a/Definition/Builder/BuilderAwareInterface.php b/Definition/Builder/BuilderAwareInterface.php
index bb40307e1..cf646a140 100644
--- a/Definition/Builder/BuilderAwareInterface.php
+++ b/Definition/Builder/BuilderAwareInterface.php
@@ -20,8 +20,6 @@ interface BuilderAwareInterface
 {
     /**
      * Sets a custom children builder.
-     *
-     * @return void
      */
-    public function setBuilder(NodeBuilder $builder);
+    public function setBuilder(NodeBuilder $builder): void;
 }
diff --git a/Definition/Builder/ExprBuilder.php b/Definition/Builder/ExprBuilder.php
index 93cdb49dd..e802df2ee 100644
--- a/Definition/Builder/ExprBuilder.php
+++ b/Definition/Builder/ExprBuilder.php
@@ -26,15 +26,13 @@ class ExprBuilder
     public const TYPE_NULL = 'null';
     public const TYPE_ARRAY = 'array';
 
-    protected $node;
+    public string $allowedTypes;
+    public ?\Closure $ifPart = null;
+    public ?\Closure $thenPart = null;
 
-    public $allowedTypes;
-    public $ifPart;
-    public $thenPart;
-
-    public function __construct(NodeDefinition $node)
-    {
-        $this->node = $node;
+    public function __construct(
+        protected NodeDefinition $node,
+    ) {
     }
 
     /**
@@ -102,7 +100,7 @@ public function ifNull(): static
      */
     public function ifEmpty(): static
     {
-        $this->ifPart = static fn ($v) => empty($v);
+        $this->ifPart = static fn ($v) => !$v;
         $this->allowedTypes = self::TYPE_ANY;
 
         return $this;
@@ -196,7 +194,7 @@ public function thenEmptyArray(): static
      */
     public function thenInvalid(string $message): static
     {
-        $this->thenPart = static fn ($v) => throw new \InvalidArgumentException(sprintf($message, json_encode($v)));
+        $this->thenPart = static fn ($v) => throw new \InvalidArgumentException(\sprintf($message, json_encode($v)));
 
         return $this;
     }
diff --git a/Definition/Builder/MergeBuilder.php b/Definition/Builder/MergeBuilder.php
index f8980a6e0..b90865cfc 100644
--- a/Definition/Builder/MergeBuilder.php
+++ b/Definition/Builder/MergeBuilder.php
@@ -18,13 +18,12 @@
  */
 class MergeBuilder
 {
-    protected $node;
-    public $allowFalse = false;
-    public $allowOverwrite = true;
+    public bool $allowFalse = false;
+    public bool $allowOverwrite = true;
 
-    public function __construct(NodeDefinition $node)
-    {
-        $this->node = $node;
+    public function __construct(
+        protected NodeDefinition $node,
+    ) {
     }
 
     /**
diff --git a/Definition/Builder/NodeBuilder.php b/Definition/Builder/NodeBuilder.php
index 93069d437..b3fa7bfd5 100644
--- a/Definition/Builder/NodeBuilder.php
+++ b/Definition/Builder/NodeBuilder.php
@@ -18,8 +18,8 @@
  */
 class NodeBuilder implements NodeParentInterface
 {
-    protected $parent;
-    protected $nodeMapping;
+    protected (NodeDefinition&ParentNodeDefinitionInterface)|null $parent = null;
+    protected array $nodeMapping;
 
     public function __construct()
     {
@@ -31,6 +31,7 @@ public function __construct()
             'float' => FloatNodeDefinition::class,
             'array' => ArrayNodeDefinition::class,
             'enum' => EnumNodeDefinition::class,
+            'string' => StringNodeDefinition::class,
         ];
     }
 
@@ -39,11 +40,8 @@ public function __construct()
      *
      * @return $this
      */
-    public function setParent(?ParentNodeDefinitionInterface $parent = null): static
+    public function setParent((NodeDefinition&ParentNodeDefinitionInterface)|null $parent): static
     {
-        if (1 > \func_num_args()) {
-            trigger_deprecation('symfony/form', '6.2', 'Calling "%s()" without any arguments is deprecated, pass null explicitly instead.', __METHOD__);
-        }
         $this->parent = $parent;
 
         return $this;
@@ -105,12 +103,18 @@ public function variableNode(string $name): VariableNodeDefinition
         return $this->node($name, 'variable');
     }
 
+    /**
+     * Creates a child string node.
+     */
+    public function stringNode(string $name): StringNodeDefinition
+    {
+        return $this->node($name, 'string');
+    }
+
     /**
      * Returns the parent node.
-     *
-     * @return NodeDefinition&ParentNodeDefinitionInterface
      */
-    public function end()
+    public function end(): NodeDefinition&ParentNodeDefinitionInterface
     {
         return $this->parent;
     }
@@ -190,13 +194,13 @@ protected function getNodeClass(string $type): string
         $type = strtolower($type);
 
         if (!isset($this->nodeMapping[$type])) {
-            throw new \RuntimeException(sprintf('The node type "%s" is not registered.', $type));
+            throw new \RuntimeException(\sprintf('The node type "%s" is not registered.', $type));
         }
 
         $class = $this->nodeMapping[$type];
 
         if (!class_exists($class)) {
-            throw new \RuntimeException(sprintf('The node class "%s" does not exist.', $class));
+            throw new \RuntimeException(\sprintf('The node class "%s" does not exist.', $class));
         }
 
         return $class;
diff --git a/Definition/Builder/NodeDefinition.php b/Definition/Builder/NodeDefinition.php
index cf2173e17..54e976e24 100644
--- a/Definition/Builder/NodeDefinition.php
+++ b/Definition/Builder/NodeDefinition.php
@@ -22,21 +22,21 @@
  */
 abstract class NodeDefinition implements NodeParentInterface
 {
-    protected $name;
-    protected $normalization;
-    protected $validation;
-    protected $defaultValue;
-    protected $default = false;
-    protected $required = false;
-    protected $deprecation = [];
-    protected $merge;
-    protected $allowEmptyValue = true;
-    protected $nullEquivalent;
-    protected $trueEquivalent = true;
-    protected $falseEquivalent = false;
-    protected $pathSeparator = BaseNode::DEFAULT_PATH_SEPARATOR;
-    protected $parent;
-    protected $attributes = [];
+    protected ?string $name = null;
+    protected NormalizationBuilder $normalization;
+    protected ValidationBuilder $validation;
+    protected mixed $defaultValue;
+    protected bool $default = false;
+    protected bool $required = false;
+    protected array $deprecation = [];
+    protected MergeBuilder $merge;
+    protected bool $allowEmptyValue = true;
+    protected mixed $nullEquivalent = null;
+    protected mixed $trueEquivalent = true;
+    protected mixed $falseEquivalent = false;
+    protected string $pathSeparator = BaseNode::DEFAULT_PATH_SEPARATOR;
+    protected NodeParentInterface|NodeInterface|null $parent;
+    protected array $attributes = [];
 
     public function __construct(?string $name, ?NodeParentInterface $parent = null)
     {
@@ -90,8 +90,10 @@ public function attribute(string $key, mixed $value): static
 
     /**
      * Returns the parent node.
+     *
+     * @return NodeParentInterface|NodeBuilder|self|ArrayNodeDefinition|VariableNodeDefinition
      */
-    public function end(): NodeParentInterface|NodeBuilder|self|ArrayNodeDefinition|VariableNodeDefinition|null
+    public function end(): NodeParentInterface
     {
         return $this->parent;
     }
diff --git a/Definition/Builder/NormalizationBuilder.php b/Definition/Builder/NormalizationBuilder.php
index 1f6b34441..8a8141c19 100644
--- a/Definition/Builder/NormalizationBuilder.php
+++ b/Definition/Builder/NormalizationBuilder.php
@@ -18,14 +18,13 @@
  */
 class NormalizationBuilder
 {
-    protected $node;
-    public $before = [];
-    public $declaredTypes = [];
-    public $remappings = [];
+    public array $before = [];
+    public array $declaredTypes = [];
+    public array $remappings = [];
 
-    public function __construct(NodeDefinition $node)
-    {
-        $this->node = $node;
+    public function __construct(
+        protected NodeDefinition $node,
+    ) {
     }
 
     /**
diff --git a/Definition/Builder/NumericNodeDefinition.php b/Definition/Builder/NumericNodeDefinition.php
index 890910c95..06dc97994 100644
--- a/Definition/Builder/NumericNodeDefinition.php
+++ b/Definition/Builder/NumericNodeDefinition.php
@@ -20,8 +20,8 @@
  */
 abstract class NumericNodeDefinition extends ScalarNodeDefinition
 {
-    protected $min;
-    protected $max;
+    protected int|float|null $min = null;
+    protected int|float|null $max = null;
 
     /**
      * Ensures that the value is smaller than the given reference.
@@ -33,7 +33,7 @@ abstract class NumericNodeDefinition extends ScalarNodeDefinition
     public function max(int|float $max): static
     {
         if (isset($this->min) && $this->min > $max) {
-            throw new \InvalidArgumentException(sprintf('You cannot define a max(%s) as you already have a min(%s).', $max, $this->min));
+            throw new \InvalidArgumentException(\sprintf('You cannot define a max(%s) as you already have a min(%s).', $max, $this->min));
         }
         $this->max = $max;
 
@@ -50,7 +50,7 @@ public function max(int|float $max): static
     public function min(int|float $min): static
     {
         if (isset($this->max) && $this->max < $min) {
-            throw new \InvalidArgumentException(sprintf('You cannot define a min(%s) as you already have a max(%s).', $min, $this->max));
+            throw new \InvalidArgumentException(\sprintf('You cannot define a min(%s) as you already have a max(%s).', $min, $this->max));
         }
         $this->min = $min;
 
diff --git a/Definition/Builder/StringNodeDefinition.php b/Definition/Builder/StringNodeDefinition.php
new file mode 100644
index 000000000..c86f1bfd7
--- /dev/null
+++ b/Definition/Builder/StringNodeDefinition.php
@@ -0,0 +1,34 @@
+<?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\Config\Definition\Builder;
+
+use Symfony\Component\Config\Definition\StringNode;
+
+/**
+ * This class provides a fluent interface for defining a node.
+ *
+ * @author Raffaele Carelle <raffaele.carelle@gmail.com>
+ */
+class StringNodeDefinition extends ScalarNodeDefinition
+{
+    public function __construct(?string $name, ?NodeParentInterface $parent = null)
+    {
+        parent::__construct($name, $parent);
+
+        $this->nullEquivalent = '';
+    }
+
+    protected function instantiateNode(): StringNode
+    {
+        return new StringNode($this->name, $this->parent, $this->pathSeparator);
+    }
+}
diff --git a/Definition/Builder/TreeBuilder.php b/Definition/Builder/TreeBuilder.php
index f7da3e794..5170e19d1 100644
--- a/Definition/Builder/TreeBuilder.php
+++ b/Definition/Builder/TreeBuilder.php
@@ -20,15 +20,8 @@
  */
 class TreeBuilder implements NodeParentInterface
 {
-    /**
-     * @var NodeInterface|null
-     */
-    protected $tree;
-
-    /**
-     * @var NodeDefinition
-     */
-    protected $root;
+    protected ?NodeInterface $tree = null;
+    protected ?NodeDefinition $root = null;
 
     public function __construct(string $name, string $type = 'array', ?NodeBuilder $builder = null)
     {
@@ -54,10 +47,7 @@ public function buildTree(): NodeInterface
         return $this->tree ??= $this->root->getNode(true);
     }
 
-    /**
-     * @return void
-     */
-    public function setPathSeparator(string $separator)
+    public function setPathSeparator(string $separator): void
     {
         // unset last built as changing path separator changes all nodes
         $this->tree = null;
diff --git a/Definition/Builder/ValidationBuilder.php b/Definition/Builder/ValidationBuilder.php
index 64623d6d6..ad2239349 100644
--- a/Definition/Builder/ValidationBuilder.php
+++ b/Definition/Builder/ValidationBuilder.php
@@ -18,12 +18,11 @@
  */
 class ValidationBuilder
 {
-    protected $node;
-    public $rules = [];
+    public array $rules = [];
 
-    public function __construct(NodeDefinition $node)
-    {
-        $this->node = $node;
+    public function __construct(
+        protected NodeDefinition $node,
+    ) {
     }
 
     /**
diff --git a/Definition/ConfigurationInterface.php b/Definition/ConfigurationInterface.php
index 7b5d443fe..97a325bb6 100644
--- a/Definition/ConfigurationInterface.php
+++ b/Definition/ConfigurationInterface.php
@@ -22,8 +22,6 @@ interface ConfigurationInterface
 {
     /**
      * Generates the configuration tree builder.
-     *
-     * @return TreeBuilder
      */
-    public function getConfigTreeBuilder();
+    public function getConfigTreeBuilder(): TreeBuilder;
 }
diff --git a/Definition/Dumper/XmlReferenceDumper.php b/Definition/Dumper/XmlReferenceDumper.php
index aac2d8456..2131c7131 100644
--- a/Definition/Dumper/XmlReferenceDumper.php
+++ b/Definition/Dumper/XmlReferenceDumper.php
@@ -31,18 +31,12 @@ class XmlReferenceDumper
 {
     private ?string $reference = null;
 
-    /**
-     * @return string
-     */
-    public function dump(ConfigurationInterface $configuration, ?string $namespace = null)
+    public function dump(ConfigurationInterface $configuration, ?string $namespace = null): string
     {
         return $this->dumpNode($configuration->getConfigTreeBuilder()->buildTree(), $namespace);
     }
 
-    /**
-     * @return string
-     */
-    public function dumpNode(NodeInterface $node, ?string $namespace = null)
+    public function dumpNode(NodeInterface $node, ?string $namespace = null): string
     {
         $this->reference = '';
         $this->writeNode($node, 0, true, $namespace);
@@ -151,7 +145,7 @@ private function writeNode(NodeInterface $node, int $depth = 0, bool $root = fal
 
                 if ($child instanceof BaseNode && $child->isDeprecated()) {
                     $deprecation = $child->getDeprecation($child->getName(), $node->getPath());
-                    $comments[] = sprintf('Deprecated (%s)', ($deprecation['package'] || $deprecation['version'] ? "Since {$deprecation['package']} {$deprecation['version']}: " : '').$deprecation['message']);
+                    $comments[] = \sprintf('Deprecated (%s)', ($deprecation['package'] || $deprecation['version'] ? "Since {$deprecation['package']} {$deprecation['version']}: " : '').$deprecation['message']);
                 }
 
                 if ($child instanceof EnumNode) {
@@ -205,7 +199,7 @@ private function writeNode(NodeInterface $node, int $depth = 0, bool $root = fal
         $rootOpenTag = '<'.$rootName;
         if (1 >= ($attributesCount = \count($rootAttributes))) {
             if (1 === $attributesCount) {
-                $rootOpenTag .= sprintf(' %s="%s"', current(array_keys($rootAttributes)), $this->writeValue(current($rootAttributes)));
+                $rootOpenTag .= \sprintf(' %s="%s"', current(array_keys($rootAttributes)), $this->writeValue(current($rootAttributes)));
             }
 
             $rootOpenTag .= $rootIsEmptyTag ? ' />' : '>';
@@ -221,7 +215,7 @@ private function writeNode(NodeInterface $node, int $depth = 0, bool $root = fal
             $i = 1;
 
             foreach ($rootAttributes as $attrName => $attrValue) {
-                $attr = sprintf('%s="%s"', $attrName, $this->writeValue($attrValue));
+                $attr = \sprintf('%s="%s"', $attrName, $this->writeValue($attrValue));
 
                 $this->writeLine($attr, $depth + 4);
 
@@ -258,7 +252,7 @@ private function writeLine(string $text, int $indent = 0): void
         $indent = \strlen($text) + $indent;
         $format = '%'.$indent.'s';
 
-        $this->reference .= sprintf($format, $text).\PHP_EOL;
+        $this->reference .= \sprintf($format, $text).\PHP_EOL;
     }
 
     /**
@@ -286,7 +280,7 @@ private function writeValue(mixed $value): string
             return 'null';
         }
 
-        if (empty($value)) {
+        if (!$value) {
             return '';
         }
 
diff --git a/Definition/Dumper/YamlReferenceDumper.php b/Definition/Dumper/YamlReferenceDumper.php
index abcf1bd9e..267444d92 100644
--- a/Definition/Dumper/YamlReferenceDumper.php
+++ b/Definition/Dumper/YamlReferenceDumper.php
@@ -29,24 +29,18 @@ class YamlReferenceDumper
 {
     private ?string $reference = null;
 
-    /**
-     * @return string
-     */
-    public function dump(ConfigurationInterface $configuration)
+    public function dump(ConfigurationInterface $configuration): string
     {
         return $this->dumpNode($configuration->getConfigTreeBuilder()->buildTree());
     }
 
-    /**
-     * @return string
-     */
-    public function dumpAtPath(ConfigurationInterface $configuration, string $path)
+    public function dumpAtPath(ConfigurationInterface $configuration, string $path): string
     {
         $rootNode = $node = $configuration->getConfigTreeBuilder()->buildTree();
 
         foreach (explode('.', $path) as $step) {
             if (!$node instanceof ArrayNode) {
-                throw new \UnexpectedValueException(sprintf('Unable to find node at path "%s.%s".', $rootNode->getName(), $path));
+                throw new \UnexpectedValueException(\sprintf('Unable to find node at path "%s.%s".', $rootNode->getName(), $path));
             }
 
             /** @var NodeInterface[] $children */
@@ -60,16 +54,13 @@ public function dumpAtPath(ConfigurationInterface $configuration, string $path)
                 }
             }
 
-            throw new \UnexpectedValueException(sprintf('Unable to find node at path "%s.%s".', $rootNode->getName(), $path));
+            throw new \UnexpectedValueException(\sprintf('Unable to find node at path "%s.%s".', $rootNode->getName(), $path));
         }
 
         return $this->dumpNode($node);
     }
 
-    /**
-     * @return string
-     */
-    public function dumpNode(NodeInterface $node)
+    public function dumpNode(NodeInterface $node): string
     {
         $this->reference = '';
         $this->writeNode($node);
@@ -130,7 +121,7 @@ private function writeNode(NodeInterface $node, ?NodeInterface $parentNode = nul
         // deprecated?
         if ($node instanceof BaseNode && $node->isDeprecated()) {
             $deprecation = $node->getDeprecation($node->getName(), $parentNode ? $parentNode->getPath() : $node->getPath());
-            $comments[] = sprintf('Deprecated (%s)', ($deprecation['package'] || $deprecation['version'] ? "Since {$deprecation['package']} {$deprecation['version']}: " : '').$deprecation['message']);
+            $comments[] = \sprintf('Deprecated (%s)', ($deprecation['package'] || $deprecation['version'] ? "Since {$deprecation['package']} {$deprecation['version']}: " : '').$deprecation['message']);
         }
 
         // example
@@ -142,12 +133,12 @@ private function writeNode(NodeInterface $node, ?NodeInterface $parentNode = nul
         $comments = \count($comments) ? '# '.implode(', ', $comments) : '';
 
         $key = $prototypedArray ? '-' : $node->getName().':';
-        $text = rtrim(sprintf('%-21s%s %s', $key, $default, $comments), ' ');
+        $text = rtrim(\sprintf('%-21s%s %s', $key, $default, $comments), ' ');
 
         if ($node instanceof BaseNode && $info = $node->getInfo()) {
             $this->writeLine('');
             // indenting multi-line info
-            $info = str_replace("\n", sprintf("\n%".($depth * 4).'s# ', ' '), $info);
+            $info = str_replace("\n", \sprintf("\n%".($depth * 4).'s# ', ' '), $info);
             $this->writeLine('# '.$info, $depth * 4);
         }
 
@@ -189,7 +180,7 @@ private function writeLine(string $text, int $indent = 0): void
         $indent = \strlen($text) + $indent;
         $format = '%'.$indent.'s';
 
-        $this->reference .= sprintf($format, $text)."\n";
+        $this->reference .= \sprintf($format, $text)."\n";
     }
 
     private function writeArray(array $array, int $depth, bool $asComment = false): void
@@ -208,7 +199,7 @@ private function writeArray(array $array, int $depth, bool $asComment = false):
             if ($isIndexed) {
                 $this->writeLine($prefix.'- '.$val, $depth * 4);
             } else {
-                $this->writeLine(sprintf('%s%-20s %s', $prefix, $key.':', $val), $depth * 4);
+                $this->writeLine(\sprintf('%s%-20s %s', $prefix, $key.':', $val), $depth * 4);
             }
 
             if (\is_array($value)) {
diff --git a/Definition/EnumNode.php b/Definition/EnumNode.php
index f5acbe906..b253406c8 100644
--- a/Definition/EnumNode.php
+++ b/Definition/EnumNode.php
@@ -34,11 +34,11 @@ public function __construct(?string $name, ?NodeInterface $parent = null, array
             }
 
             if (!$value instanceof \UnitEnum) {
-                throw new \InvalidArgumentException(sprintf('"%s" only supports scalar, enum, or null values, "%s" given.', __CLASS__, get_debug_type($value)));
+                throw new \InvalidArgumentException(\sprintf('"%s" only supports scalar, enum, or null values, "%s" given.', __CLASS__, get_debug_type($value)));
             }
 
             if ($value::class !== ($enumClass ??= $value::class)) {
-                throw new \InvalidArgumentException(sprintf('"%s" only supports one type of enum, "%s" and "%s" passed.', __CLASS__, $enumClass, $value::class));
+                throw new \InvalidArgumentException(\sprintf('"%s" only supports one type of enum, "%s" and "%s" passed.', __CLASS__, $enumClass, $value::class));
             }
         }
 
@@ -46,10 +46,7 @@ public function __construct(?string $name, ?NodeInterface $parent = null, array
         $this->values = $values;
     }
 
-    /**
-     * @return array
-     */
-    public function getValues()
+    public function getValues(): array
     {
         return $this->values;
     }
@@ -68,10 +65,7 @@ public function getPermissibleValues(string $separator): string
         }, $this->values)));
     }
 
-    /**
-     * @return void
-     */
-    protected function validateType(mixed $value)
+    protected function validateType(mixed $value): void
     {
         if ($value instanceof \UnitEnum) {
             return;
@@ -85,7 +79,7 @@ protected function finalizeValue(mixed $value): mixed
         $value = parent::finalizeValue($value);
 
         if (!\in_array($value, $this->values, true)) {
-            $ex = new InvalidConfigurationException(sprintf('The value %s is not allowed for path "%s". Permissible values: %s', json_encode($value), $this->getPath(), $this->getPermissibleValues(', ')));
+            $ex = new InvalidConfigurationException(\sprintf('The value %s is not allowed for path "%s". Permissible values: %s', json_encode($value), $this->getPath(), $this->getPermissibleValues(', ')));
             $ex->setPath($this->getPath());
 
             throw $ex;
diff --git a/Definition/Exception/InvalidConfigurationException.php b/Definition/Exception/InvalidConfigurationException.php
index 794447bf8..e3f29f8e6 100644
--- a/Definition/Exception/InvalidConfigurationException.php
+++ b/Definition/Exception/InvalidConfigurationException.php
@@ -22,10 +22,7 @@ class InvalidConfigurationException extends Exception
     private ?string $path = null;
     private bool $containsHints = false;
 
-    /**
-     * @return void
-     */
-    public function setPath(string $path)
+    public function setPath(string $path): void
     {
         $this->path = $path;
     }
@@ -37,10 +34,8 @@ public function getPath(): ?string
 
     /**
      * Adds extra information that is suffixed to the original exception message.
-     *
-     * @return void
      */
-    public function addHint(string $hint)
+    public function addHint(string $hint): void
     {
         if (!$this->containsHints) {
             $this->message .= "\nHint: ".$hint;
diff --git a/Definition/FloatNode.php b/Definition/FloatNode.php
index ce4193e09..8b922804b 100644
--- a/Definition/FloatNode.php
+++ b/Definition/FloatNode.php
@@ -20,10 +20,7 @@
  */
 class FloatNode extends NumericNode
 {
-    /**
-     * @return void
-     */
-    protected function validateType(mixed $value)
+    protected function validateType(mixed $value): void
     {
         // Integers are also accepted, we just cast them
         if (\is_int($value)) {
@@ -31,7 +28,7 @@ protected function validateType(mixed $value)
         }
 
         if (!\is_float($value)) {
-            $ex = new InvalidTypeException(sprintf('Invalid type for path "%s". Expected "float", but got "%s".', $this->getPath(), get_debug_type($value)));
+            $ex = new InvalidTypeException(\sprintf('Invalid type for path "%s". Expected "float", but got "%s".', $this->getPath(), get_debug_type($value)));
             if ($hint = $this->getInfo()) {
                 $ex->addHint($hint);
             }
diff --git a/Definition/IntegerNode.php b/Definition/IntegerNode.php
index 4a3e3253c..6fa3e6032 100644
--- a/Definition/IntegerNode.php
+++ b/Definition/IntegerNode.php
@@ -20,13 +20,10 @@
  */
 class IntegerNode extends NumericNode
 {
-    /**
-     * @return void
-     */
-    protected function validateType(mixed $value)
+    protected function validateType(mixed $value): void
     {
         if (!\is_int($value)) {
-            $ex = new InvalidTypeException(sprintf('Invalid type for path "%s". Expected "int", but got "%s".', $this->getPath(), get_debug_type($value)));
+            $ex = new InvalidTypeException(\sprintf('Invalid type for path "%s". Expected "int", but got "%s".', $this->getPath(), get_debug_type($value)));
             if ($hint = $this->getInfo()) {
                 $ex->addHint($hint);
             }
diff --git a/Definition/Loader/DefinitionFileLoader.php b/Definition/Loader/DefinitionFileLoader.php
index 940b894f7..09147f791 100644
--- a/Definition/Loader/DefinitionFileLoader.php
+++ b/Definition/Loader/DefinitionFileLoader.php
@@ -81,7 +81,7 @@ private function executeCallback(callable $callback, DefinitionConfigurator $con
             $reflectionType = $parameter->getType();
 
             if (!$reflectionType instanceof \ReflectionNamedType) {
-                throw new \InvalidArgumentException(sprintf('Could not resolve argument "$%s" for "%s". You must typehint it (for example with "%s").', $parameter->getName(), $path, DefinitionConfigurator::class));
+                throw new \InvalidArgumentException(\sprintf('Could not resolve argument "$%s" for "%s". You must typehint it (for example with "%s").', $parameter->getName(), $path, DefinitionConfigurator::class));
             }
 
             $arguments[] = match ($reflectionType->getName()) {
diff --git a/Definition/NumericNode.php b/Definition/NumericNode.php
index 22359fd25..a97850c9d 100644
--- a/Definition/NumericNode.php
+++ b/Definition/NumericNode.php
@@ -20,14 +20,14 @@
  */
 class NumericNode extends ScalarNode
 {
-    protected $min;
-    protected $max;
-
-    public function __construct(?string $name, ?NodeInterface $parent = null, int|float|null $min = null, int|float|null $max = null, string $pathSeparator = BaseNode::DEFAULT_PATH_SEPARATOR)
-    {
+    public function __construct(
+        ?string $name,
+        ?NodeInterface $parent = null,
+        protected int|float|null $min = null,
+        protected int|float|null $max = null,
+        string $pathSeparator = BaseNode::DEFAULT_PATH_SEPARATOR,
+    ) {
         parent::__construct($name, $parent, $pathSeparator);
-        $this->min = $min;
-        $this->max = $max;
     }
 
     protected function finalizeValue(mixed $value): mixed
@@ -36,10 +36,10 @@ protected function finalizeValue(mixed $value): mixed
 
         $errorMsg = null;
         if (isset($this->min) && $value < $this->min) {
-            $errorMsg = sprintf('The value %s is too small for path "%s". Should be greater than or equal to %s', $value, $this->getPath(), $this->min);
+            $errorMsg = \sprintf('The value %s is too small for path "%s". Should be greater than or equal to %s', $value, $this->getPath(), $this->min);
         }
         if (isset($this->max) && $value > $this->max) {
-            $errorMsg = sprintf('The value %s is too big for path "%s". Should be less than or equal to %s', $value, $this->getPath(), $this->max);
+            $errorMsg = \sprintf('The value %s is too big for path "%s". Should be less than or equal to %s', $value, $this->getPath(), $this->max);
         }
         if (isset($errorMsg)) {
             $ex = new InvalidConfigurationException($errorMsg);
diff --git a/Definition/PrototypeNodeInterface.php b/Definition/PrototypeNodeInterface.php
index 9dce7444b..109889f37 100644
--- a/Definition/PrototypeNodeInterface.php
+++ b/Definition/PrototypeNodeInterface.php
@@ -20,8 +20,6 @@ interface PrototypeNodeInterface extends NodeInterface
 {
     /**
      * Sets the name of the node.
-     *
-     * @return void
      */
-    public function setName(string $name);
+    public function setName(string $name): void;
 }
diff --git a/Definition/PrototypedArrayNode.php b/Definition/PrototypedArrayNode.php
index c105ac1f3..a901dab78 100644
--- a/Definition/PrototypedArrayNode.php
+++ b/Definition/PrototypedArrayNode.php
@@ -23,12 +23,12 @@
  */
 class PrototypedArrayNode extends ArrayNode
 {
-    protected $prototype;
-    protected $keyAttribute;
-    protected $removeKeyAttribute = false;
-    protected $minNumberOfElements = 0;
-    protected $defaultValue = [];
-    protected $defaultChildren;
+    protected PrototypeNodeInterface $prototype;
+    protected ?string $keyAttribute = null;
+    protected bool $removeKeyAttribute = false;
+    protected int $minNumberOfElements = 0;
+    protected array $defaultValue = [];
+    protected ?array $defaultChildren = null;
     /**
      * @var NodeInterface[] An array of the prototypes of the simplified value children
      */
@@ -37,10 +37,8 @@ class PrototypedArrayNode extends ArrayNode
     /**
      * Sets the minimum number of elements that a prototype based node must
      * contain. By default this is zero, meaning no elements.
-     *
-     * @return void
      */
-    public function setMinNumberOfElements(int $number)
+    public function setMinNumberOfElements(int $number): void
     {
         $this->minNumberOfElements = $number;
     }
@@ -68,10 +66,8 @@ public function setMinNumberOfElements(int $number)
      *
      * @param string $attribute The name of the attribute which value is to be used as a key
      * @param bool   $remove    Whether or not to remove the key
-     *
-     * @return void
      */
-    public function setKeyAttribute(string $attribute, bool $remove = true)
+    public function setKeyAttribute(string $attribute, bool $remove = true): void
     {
         $this->keyAttribute = $attribute;
         $this->removeKeyAttribute = $remove;
@@ -87,10 +83,8 @@ public function getKeyAttribute(): ?string
 
     /**
      * Sets the default value of this node.
-     *
-     * @return void
      */
-    public function setDefaultValue(array $value)
+    public function setDefaultValue(array $value): void
     {
         $this->defaultValue = $value;
     }
@@ -104,10 +98,8 @@ public function hasDefaultValue(): bool
      * Adds default children when none are set.
      *
      * @param int|string|array|null $children The number of children|The child name|The children names to be added
-     *
-     * @return void
      */
-    public function setAddChildrenIfNoneSet(int|string|array|null $children = ['defaults'])
+    public function setAddChildrenIfNoneSet(int|string|array|null $children = ['defaults']): void
     {
         if (null === $children) {
             $this->defaultChildren = ['defaults'];
@@ -137,10 +129,8 @@ public function getDefaultValue(): mixed
 
     /**
      * Sets the node prototype.
-     *
-     * @return void
      */
-    public function setPrototype(PrototypeNodeInterface $node)
+    public function setPrototype(PrototypeNodeInterface $node): void
     {
         $this->prototype = $node;
     }
@@ -156,11 +146,9 @@ public function getPrototype(): PrototypeNodeInterface
     /**
      * Disable adding concrete children for prototyped nodes.
      *
-     * @return never
-     *
      * @throws Exception
      */
-    public function addChild(NodeInterface $node)
+    public function addChild(NodeInterface $node): never
     {
         throw new Exception('A prototyped array node cannot have concrete children.');
     }
@@ -168,7 +156,7 @@ public function addChild(NodeInterface $node)
     protected function finalizeValue(mixed $value): mixed
     {
         if (false === $value) {
-            throw new UnsetKeyException(sprintf('Unsetting key for path "%s", value: %s.', $this->getPath(), json_encode($value)));
+            throw new UnsetKeyException(\sprintf('Unsetting key for path "%s", value: false.', $this->getPath()));
         }
 
         foreach ($value as $k => $v) {
@@ -181,7 +169,7 @@ protected function finalizeValue(mixed $value): mixed
         }
 
         if (\count($value) < $this->minNumberOfElements) {
-            $ex = new InvalidConfigurationException(sprintf('The path "%s" should have at least %d element(s) defined.', $this->getPath(), $this->minNumberOfElements));
+            $ex = new InvalidConfigurationException(\sprintf('The path "%s" should have at least %d element(s) defined.', $this->getPath(), $this->minNumberOfElements));
             $ex->setPath($this->getPath());
 
             throw $ex;
@@ -206,7 +194,7 @@ protected function normalizeValue(mixed $value): mixed
         foreach ($value as $k => $v) {
             if (null !== $this->keyAttribute && \is_array($v)) {
                 if (!isset($v[$this->keyAttribute]) && \is_int($k) && $isList) {
-                    $ex = new InvalidConfigurationException(sprintf('The attribute "%s" must be set for path "%s".', $this->keyAttribute, $this->getPath()));
+                    $ex = new InvalidConfigurationException(\sprintf('The attribute "%s" must be set for path "%s".', $this->keyAttribute, $this->getPath()));
                     $ex->setPath($this->getPath());
 
                     throw $ex;
@@ -229,17 +217,15 @@ protected function normalizeValue(mixed $value): mixed
                             $valuePrototype = current($this->valuePrototypes) ?: clone $children['value'];
                             $valuePrototype->parent = $this;
                             $originalClosures = $this->prototype->normalizationClosures;
-                            if (\is_array($originalClosures)) {
-                                $valuePrototypeClosures = $valuePrototype->normalizationClosures;
-                                $valuePrototype->normalizationClosures = \is_array($valuePrototypeClosures) ? array_merge($originalClosures, $valuePrototypeClosures) : $originalClosures;
-                            }
+                            $valuePrototypeClosures = $valuePrototype->normalizationClosures;
+                            $valuePrototype->normalizationClosures = array_merge($originalClosures, $valuePrototypeClosures);
                             $this->valuePrototypes[$k] = $valuePrototype;
                         }
                     }
                 }
 
                 if (\array_key_exists($k, $normalized)) {
-                    $ex = new DuplicateKeyException(sprintf('Duplicate key "%s" for path "%s".', $k, $this->getPath()));
+                    $ex = new DuplicateKeyException(\sprintf('Duplicate key "%s" for path "%s".', $k, $this->getPath()));
                     $ex->setPath($this->getPath());
 
                     throw $ex;
@@ -280,7 +266,7 @@ protected function mergeValues(mixed $leftSide, mixed $rightSide): mixed
             // no conflict
             if (!\array_key_exists($k, $leftSide)) {
                 if (!$this->allowNewKeys) {
-                    $ex = new InvalidConfigurationException(sprintf('You are not allowed to define new elements for path "%s". Please define all elements for this path in one config file.', $this->getPath()));
+                    $ex = new InvalidConfigurationException(\sprintf('You are not allowed to define new elements for path "%s". Please define all elements for this path in one config file.', $this->getPath()));
                     $ex->setPath($this->getPath());
 
                     throw $ex;
diff --git a/Definition/ScalarNode.php b/Definition/ScalarNode.php
index e11fa1ee1..341769249 100644
--- a/Definition/ScalarNode.php
+++ b/Definition/ScalarNode.php
@@ -27,13 +27,10 @@
  */
 class ScalarNode extends VariableNode
 {
-    /**
-     * @return void
-     */
-    protected function validateType(mixed $value)
+    protected function validateType(mixed $value): void
     {
         if (!\is_scalar($value) && null !== $value) {
-            $ex = new InvalidTypeException(sprintf('Invalid type for path "%s". Expected "scalar", but got "%s".', $this->getPath(), get_debug_type($value)));
+            $ex = new InvalidTypeException(\sprintf('Invalid type for path "%s". Expected "scalar", but got "%s".', $this->getPath(), get_debug_type($value)));
             if ($hint = $this->getInfo()) {
                 $ex->addHint($hint);
             }
diff --git a/Definition/StringNode.php b/Definition/StringNode.php
new file mode 100644
index 000000000..6687b8825
--- /dev/null
+++ b/Definition/StringNode.php
@@ -0,0 +1,40 @@
+<?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\Config\Definition;
+
+use Symfony\Component\Config\Definition\Exception\InvalidTypeException;
+
+/**
+ * This node represents a String value in the config tree.
+ *
+ * @author Raffaele Carelle <raffaele.carelle@gmail.com>
+ */
+class StringNode extends ScalarNode
+{
+    protected function validateType(mixed $value): void
+    {
+        if (!\is_string($value)) {
+            $ex = new InvalidTypeException(\sprintf('Invalid type for path "%s". Expected "string", but got "%s".', $this->getPath(), get_debug_type($value)));
+            if ($hint = $this->getInfo()) {
+                $ex->addHint($hint);
+            }
+            $ex->setPath($this->getPath());
+
+            throw $ex;
+        }
+    }
+
+    protected function getValidPlaceholderTypes(): array
+    {
+        return ['string'];
+    }
+}
diff --git a/Definition/VariableNode.php b/Definition/VariableNode.php
index 6bdc65b4e..ed1b903a1 100644
--- a/Definition/VariableNode.php
+++ b/Definition/VariableNode.php
@@ -23,14 +23,11 @@
  */
 class VariableNode extends BaseNode implements PrototypeNodeInterface
 {
-    protected $defaultValueSet = false;
-    protected $defaultValue;
-    protected $allowEmptyValue = true;
+    protected bool $defaultValueSet = false;
+    protected mixed $defaultValue = null;
+    protected bool $allowEmptyValue = true;
 
-    /**
-     * @return void
-     */
-    public function setDefaultValue(mixed $value)
+    public function setDefaultValue(mixed $value): void
     {
         $this->defaultValueSet = true;
         $this->defaultValue = $value;
@@ -52,26 +49,18 @@ public function getDefaultValue(): mixed
      * Sets if this node is allowed to have an empty value.
      *
      * @param bool $boolean True if this entity will accept empty values
-     *
-     * @return void
      */
-    public function setAllowEmptyValue(bool $boolean)
+    public function setAllowEmptyValue(bool $boolean): void
     {
         $this->allowEmptyValue = $boolean;
     }
 
-    /**
-     * @return void
-     */
-    public function setName(string $name)
+    public function setName(string $name): void
     {
         $this->name = $name;
     }
 
-    /**
-     * @return void
-     */
-    protected function validateType(mixed $value)
+    protected function validateType(mixed $value): void
     {
     }
 
@@ -80,7 +69,7 @@ protected function finalizeValue(mixed $value): mixed
         // deny environment variables only when using custom validators
         // this avoids ever passing an empty value to final validation closures
         if (!$this->allowEmptyValue && $this->isHandlingPlaceholder() && $this->finalValidationClosures) {
-            $e = new InvalidConfigurationException(sprintf('The path "%s" cannot contain an environment variable when empty values are not allowed by definition and are validated.', $this->getPath()));
+            $e = new InvalidConfigurationException(\sprintf('The path "%s" cannot contain an environment variable when empty values are not allowed by definition and are validated.', $this->getPath()));
             if ($hint = $this->getInfo()) {
                 $e->addHint($hint);
             }
@@ -90,7 +79,7 @@ protected function finalizeValue(mixed $value): mixed
         }
 
         if (!$this->allowEmptyValue && $this->isValueEmpty($value)) {
-            $ex = new InvalidConfigurationException(sprintf('The path "%s" cannot contain an empty value, but got %s.', $this->getPath(), json_encode($value)));
+            $ex = new InvalidConfigurationException(\sprintf('The path "%s" cannot contain an empty value, but got %s.', $this->getPath(), json_encode($value)));
             if ($hint = $this->getInfo()) {
                 $ex->addHint($hint);
             }
@@ -123,6 +112,6 @@ protected function mergeValues(mixed $leftSide, mixed $rightSide): mixed
      */
     protected function isValueEmpty(mixed $value): bool
     {
-        return empty($value);
+        return !$value;
     }
 }
diff --git a/Exception/FileLoaderImportCircularReferenceException.php b/Exception/FileLoaderImportCircularReferenceException.php
index 2d2a4de00..d39bde046 100644
--- a/Exception/FileLoaderImportCircularReferenceException.php
+++ b/Exception/FileLoaderImportCircularReferenceException.php
@@ -20,7 +20,7 @@ class FileLoaderImportCircularReferenceException extends LoaderLoadException
 {
     public function __construct(array $resources, int $code = 0, ?\Throwable $previous = null)
     {
-        $message = sprintf('Circular reference detected in "%s" ("%s" > "%s").', $this->varToString($resources[0]), implode('" > "', $resources), $resources[0]);
+        $message = \sprintf('Circular reference detected in "%s" ("%s" > "%s").', $this->varToString($resources[0]), implode('" > "', $resources), $resources[0]);
 
         \Exception::__construct($message, $code, $previous);
     }
diff --git a/Exception/FileLocatorFileNotFoundException.php b/Exception/FileLocatorFileNotFoundException.php
index a3fcc901b..d9e5b4f36 100644
--- a/Exception/FileLocatorFileNotFoundException.php
+++ b/Exception/FileLocatorFileNotFoundException.php
@@ -18,19 +18,16 @@
  */
 class FileLocatorFileNotFoundException extends \InvalidArgumentException
 {
-    private array $paths;
-
-    public function __construct(string $message = '', int $code = 0, ?\Throwable $previous = null, array $paths = [])
-    {
+    public function __construct(
+        string $message = '',
+        int $code = 0,
+        ?\Throwable $previous = null,
+        private array $paths = [],
+    ) {
         parent::__construct($message, $code, $previous);
-
-        $this->paths = $paths;
     }
 
-    /**
-     * @return array
-     */
-    public function getPaths()
+    public function getPaths(): array
     {
         return $this->paths;
     }
diff --git a/Exception/LoaderLoadException.php b/Exception/LoaderLoadException.php
index 2b40688a5..ce486a35f 100644
--- a/Exception/LoaderLoadException.php
+++ b/Exception/LoaderLoadException.php
@@ -31,7 +31,7 @@ public function __construct(mixed $resource, ?string $sourceResource = null, int
             try {
                 $resource = json_encode($resource, \JSON_THROW_ON_ERROR);
             } catch (\JsonException) {
-                $resource = sprintf('resource of type "%s"', get_debug_type($resource));
+                $resource = \sprintf('resource of type "%s"', get_debug_type($resource));
             }
         }
 
@@ -42,60 +42,57 @@ public function __construct(mixed $resource, ?string $sourceResource = null, int
             // Trim the trailing period of the previous message. We only want 1 period remove so no rtrim...
             if (str_ends_with($previous->getMessage(), '.')) {
                 $trimmedMessage = substr($previous->getMessage(), 0, -1);
-                $message .= sprintf('%s', $trimmedMessage).' in ';
+                $message .= \sprintf('%s', $trimmedMessage).' in ';
             } else {
-                $message .= sprintf('%s', $previous->getMessage()).' in ';
+                $message .= \sprintf('%s', $previous->getMessage()).' in ';
             }
             $message .= $resource.' ';
 
             // show tweaked trace to complete the human readable sentence
             if (null === $sourceResource) {
-                $message .= sprintf('(which is loaded in resource "%s")', $resource);
+                $message .= \sprintf('(which is loaded in resource "%s")', $resource);
             } else {
-                $message .= sprintf('(which is being imported from "%s")', $sourceResource);
+                $message .= \sprintf('(which is being imported from "%s")', $sourceResource);
             }
             $message .= '.';
 
         // if there's no previous message, present it the default way
         } elseif (null === $sourceResource) {
-            $message .= sprintf('Cannot load resource "%s".', $resource);
+            $message .= \sprintf('Cannot load resource "%s".', $resource);
         } else {
-            $message .= sprintf('Cannot import resource "%s" from "%s".', $resource, $sourceResource);
+            $message .= \sprintf('Cannot import resource "%s" from "%s".', $resource, $sourceResource);
         }
 
         // Is the resource located inside a bundle?
         if ('@' === $resource[0]) {
             $parts = explode(\DIRECTORY_SEPARATOR, $resource);
             $bundle = substr($parts[0], 1);
-            $message .= sprintf(' Make sure the "%s" bundle is correctly registered and loaded in the application kernel class.', $bundle);
-            $message .= sprintf(' If the bundle is registered, make sure the bundle path "%s" is not empty.', $resource);
+            $message .= \sprintf(' Make sure the "%s" bundle is correctly registered and loaded in the application kernel class.', $bundle);
+            $message .= \sprintf(' If the bundle is registered, make sure the bundle path "%s" is not empty.', $resource);
         } elseif (null !== $type) {
-            $message .= sprintf(' Make sure there is a loader supporting the "%s" type.', $type);
+            $message .= \sprintf(' Make sure there is a loader supporting the "%s" type.', $type);
         }
 
         parent::__construct($message, $code, $previous);
     }
 
-    /**
-     * @return string
-     */
-    protected function varToString(mixed $var)
+    protected function varToString(mixed $var): string
     {
         if (\is_object($var)) {
-            return sprintf('Object(%s)', $var::class);
+            return \sprintf('Object(%s)', $var::class);
         }
 
         if (\is_array($var)) {
             $a = [];
             foreach ($var as $k => $v) {
-                $a[] = sprintf('%s => %s', $k, $this->varToString($v));
+                $a[] = \sprintf('%s => %s', $k, $this->varToString($v));
             }
 
-            return sprintf('Array(%s)', implode(', ', $a));
+            return \sprintf('Array(%s)', implode(', ', $a));
         }
 
         if (\is_resource($var)) {
-            return sprintf('Resource(%s)', get_resource_type($var));
+            return \sprintf('Resource(%s)', get_resource_type($var));
         }
 
         if (null === $var) {
diff --git a/Exception/LogicException.php b/Exception/LogicException.php
new file mode 100644
index 000000000..d227aece4
--- /dev/null
+++ b/Exception/LogicException.php
@@ -0,0 +1,16 @@
+<?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\Config\Exception;
+
+class LogicException extends \LogicException
+{
+}
diff --git a/FileLocator.php b/FileLocator.php
index 99c35bd26..3a5064edc 100644
--- a/FileLocator.php
+++ b/FileLocator.php
@@ -20,7 +20,7 @@
  */
 class FileLocator implements FileLocatorInterface
 {
-    protected $paths;
+    protected array $paths;
 
     /**
      * @param string|string[] $paths A path or an array of paths where to look for resources
@@ -35,7 +35,7 @@ public function __construct(string|array $paths = [])
      *
      * @psalm-return ($first is true ? string : string[])
      */
-    public function locate(string $name, ?string $currentPath = null, bool $first = true)
+    public function locate(string $name, ?string $currentPath = null, bool $first = true): string|array
     {
         if ('' === $name) {
             throw new \InvalidArgumentException('An empty file name is not valid to be located.');
@@ -43,7 +43,7 @@ public function locate(string $name, ?string $currentPath = null, bool $first =
 
         if ($this->isAbsolutePath($name)) {
             if (!file_exists($name)) {
-                throw new FileLocatorFileNotFoundException(sprintf('The file "%s" does not exist.', $name), 0, null, [$name]);
+                throw new FileLocatorFileNotFoundException(\sprintf('The file "%s" does not exist.', $name), 0, null, [$name]);
             }
 
             return $name;
@@ -70,7 +70,7 @@ public function locate(string $name, ?string $currentPath = null, bool $first =
         }
 
         if (!$filepaths) {
-            throw new FileLocatorFileNotFoundException(sprintf('The file "%s" does not exist (in: "%s").', $name, implode('", "', $paths)), 0, null, $notfound);
+            throw new FileLocatorFileNotFoundException(\sprintf('The file "%s" does not exist (in: "%s").', $name, implode('", "', $paths)), 0, null, $notfound);
         }
 
         return $filepaths;
@@ -86,7 +86,8 @@ private function isAbsolutePath(string $file): bool
                 && ':' === $file[1]
                 && ('\\' === $file[2] || '/' === $file[2])
             )
-            || null !== parse_url($file, \PHP_URL_SCHEME)
+            || parse_url($file, \PHP_URL_SCHEME)
+            || str_starts_with($file, 'phar:///') // "parse_url()" doesn't handle absolute phar path, despite being valid
         ) {
             return true;
         }
diff --git a/FileLocatorInterface.php b/FileLocatorInterface.php
index 755cf018a..87cecf477 100644
--- a/FileLocatorInterface.php
+++ b/FileLocatorInterface.php
@@ -32,5 +32,5 @@ interface FileLocatorInterface
      *
      * @psalm-return ($first is true ? string : string[])
      */
-    public function locate(string $name, ?string $currentPath = null, bool $first = true);
+    public function locate(string $name, ?string $currentPath = null, bool $first = true): string|array;
 }
diff --git a/Loader/FileLoader.php b/Loader/FileLoader.php
index 8275ffcd3..8d9d84627 100644
--- a/Loader/FileLoader.php
+++ b/Loader/FileLoader.php
@@ -25,24 +25,21 @@
  */
 abstract class FileLoader extends Loader
 {
-    protected static $loading = [];
-
-    protected $locator;
+    protected static array $loading = [];
 
     private ?string $currentDir = null;
 
-    public function __construct(FileLocatorInterface $locator, ?string $env = null)
-    {
-        $this->locator = $locator;
+    public function __construct(
+        protected FileLocatorInterface $locator,
+        ?string $env = null,
+    ) {
         parent::__construct($env);
     }
 
     /**
      * Sets the current directory.
-     *
-     * @return void
      */
-    public function setCurrentDir(string $dir)
+    public function setCurrentDir(string $dir): void
     {
         $this->currentDir = $dir;
     }
@@ -64,13 +61,11 @@ public function getLocator(): FileLocatorInterface
      * @param string|null          $sourceResource The original resource importing the new resource
      * @param string|string[]|null $exclude        Glob patterns to exclude from the import
      *
-     * @return mixed
-     *
      * @throws LoaderLoadException
      * @throws FileLoaderImportCircularReferenceException
      * @throws FileLocatorFileNotFoundException
      */
-    public function import(mixed $resource, ?string $type = null, bool $ignoreErrors = false, ?string $sourceResource = null, string|array|null $exclude = null)
+    public function import(mixed $resource, ?string $type = null, bool $ignoreErrors = false, ?string $sourceResource = null, string|array|null $exclude = null): mixed
     {
         if (\is_string($resource) && \strlen($resource) !== ($i = strcspn($resource, '*?{[')) && !str_contains($resource, "\n")) {
             $excluded = [];
diff --git a/Loader/Loader.php b/Loader/Loader.php
index 66c38bbea..28e5877bf 100644
--- a/Loader/Loader.php
+++ b/Loader/Loader.php
@@ -12,6 +12,7 @@
 namespace Symfony\Component\Config\Loader;
 
 use Symfony\Component\Config\Exception\LoaderLoadException;
+use Symfony\Component\Config\Exception\LogicException;
 
 /**
  * Loader is the abstract class used by all built-in loaders.
@@ -20,33 +21,31 @@
  */
 abstract class Loader implements LoaderInterface
 {
-    protected $resolver;
-    protected $env;
+    protected ?LoaderResolverInterface $resolver = null;
 
-    public function __construct(?string $env = null)
-    {
-        $this->env = $env;
+    public function __construct(
+        protected ?string $env = null,
+    ) {
     }
 
     public function getResolver(): LoaderResolverInterface
     {
+        if (null === $this->resolver) {
+            throw new LogicException('Cannot get a resolver if none was set.');
+        }
+
         return $this->resolver;
     }
 
-    /**
-     * @return void
-     */
-    public function setResolver(LoaderResolverInterface $resolver)
+    public function setResolver(LoaderResolverInterface $resolver): void
     {
         $this->resolver = $resolver;
     }
 
     /**
      * Imports a resource.
-     *
-     * @return mixed
      */
-    public function import(mixed $resource, ?string $type = null)
+    public function import(mixed $resource, ?string $type = null): mixed
     {
         return $this->resolve($resource, $type)->load($resource, $type);
     }
diff --git a/Loader/LoaderInterface.php b/Loader/LoaderInterface.php
index 190d2c630..6ed1893a5 100644
--- a/Loader/LoaderInterface.php
+++ b/Loader/LoaderInterface.php
@@ -21,32 +21,24 @@ interface LoaderInterface
     /**
      * Loads a resource.
      *
-     * @return mixed
-     *
      * @throws \Exception If something went wrong
      */
-    public function load(mixed $resource, ?string $type = null);
+    public function load(mixed $resource, ?string $type = null): mixed;
 
     /**
      * Returns whether this class supports the given resource.
      *
      * @param mixed $resource A resource
-     *
-     * @return bool
      */
-    public function supports(mixed $resource, ?string $type = null);
+    public function supports(mixed $resource, ?string $type = null): bool;
 
     /**
      * Gets the loader resolver.
-     *
-     * @return LoaderResolverInterface
      */
-    public function getResolver();
+    public function getResolver(): LoaderResolverInterface;
 
     /**
      * Sets the loader resolver.
-     *
-     * @return void
      */
-    public function setResolver(LoaderResolverInterface $resolver);
+    public function setResolver(LoaderResolverInterface $resolver): void;
 }
diff --git a/Loader/LoaderResolver.php b/Loader/LoaderResolver.php
index 72ab33411..8308d7e89 100644
--- a/Loader/LoaderResolver.php
+++ b/Loader/LoaderResolver.php
@@ -47,10 +47,7 @@ public function resolve(mixed $resource, ?string $type = null): LoaderInterface|
         return false;
     }
 
-    /**
-     * @return void
-     */
-    public function addLoader(LoaderInterface $loader)
+    public function addLoader(LoaderInterface $loader): void
     {
         $this->loaders[] = $loader;
         $loader->setResolver($this);
diff --git a/Loader/ParamConfigurator.php b/Loader/ParamConfigurator.php
index d91de6a73..ed1045270 100644
--- a/Loader/ParamConfigurator.php
+++ b/Loader/ParamConfigurator.php
@@ -18,11 +18,9 @@
  */
 class ParamConfigurator
 {
-    private string $name;
-
-    public function __construct(string $name)
-    {
-        $this->name = $name;
+    public function __construct(
+        private string $name,
+    ) {
     }
 
     public function __toString(): string
diff --git a/Resource/ClassExistenceResource.php b/Resource/ClassExistenceResource.php
index eab04b8d0..e7851740c 100644
--- a/Resource/ClassExistenceResource.php
+++ b/Resource/ClassExistenceResource.php
@@ -23,7 +23,6 @@
  */
 class ClassExistenceResource implements SelfCheckingResourceInterface
 {
-    private string $resource;
     private ?array $exists = null;
 
     private static int $autoloadLevel = 0;
@@ -34,9 +33,10 @@ class ClassExistenceResource implements SelfCheckingResourceInterface
      * @param string    $resource The fully-qualified class name
      * @param bool|null $exists   Boolean when the existence check has already been done
      */
-    public function __construct(string $resource, ?bool $exists = null)
-    {
-        $this->resource = $resource;
+    public function __construct(
+        private string $resource,
+        ?bool $exists = null,
+    ) {
         if (null !== $exists) {
             $this->exists = [$exists, null];
         }
@@ -158,10 +158,10 @@ public static function throwOnRequiredClass(string $class, ?\Exception $previous
             throw $previous;
         }
 
-        $message = sprintf('Class "%s" not found.', $class);
+        $message = \sprintf('Class "%s" not found.', $class);
 
         if ($class !== (self::$autoloadedClass ?? $class)) {
-            $message = substr_replace($message, sprintf(' while loading "%s"', self::$autoloadedClass), -1, 0);
+            $message = substr_replace($message, \sprintf(' while loading "%s"', self::$autoloadedClass), -1, 0);
         }
 
         if (null !== $previous) {
diff --git a/Resource/DirectoryResource.php b/Resource/DirectoryResource.php
index df486a085..5fd5f65c9 100644
--- a/Resource/DirectoryResource.php
+++ b/Resource/DirectoryResource.php
@@ -21,7 +21,6 @@
 class DirectoryResource implements SelfCheckingResourceInterface
 {
     private string $resource;
-    private ?string $pattern;
 
     /**
      * @param string      $resource The file path to the resource
@@ -29,13 +28,14 @@ class DirectoryResource implements SelfCheckingResourceInterface
      *
      * @throws \InvalidArgumentException
      */
-    public function __construct(string $resource, ?string $pattern = null)
-    {
+    public function __construct(
+        string $resource,
+        private ?string $pattern = null,
+    ) {
         $resolvedResource = realpath($resource) ?: (file_exists($resource) ? $resource : false);
-        $this->pattern = $pattern;
 
         if (false === $resolvedResource || !is_dir($resolvedResource)) {
-            throw new \InvalidArgumentException(sprintf('The directory "%s" does not exist.', $resource));
+            throw new \InvalidArgumentException(\sprintf('The directory "%s" does not exist.', $resource));
         }
 
         $this->resource = $resolvedResource;
diff --git a/Resource/FileExistenceResource.php b/Resource/FileExistenceResource.php
index 666866ee4..4722537d8 100644
--- a/Resource/FileExistenceResource.php
+++ b/Resource/FileExistenceResource.php
@@ -23,16 +23,14 @@
  */
 class FileExistenceResource implements SelfCheckingResourceInterface
 {
-    private string $resource;
-
     private bool $exists;
 
     /**
      * @param string $resource The file path to the resource
      */
-    public function __construct(string $resource)
-    {
-        $this->resource = $resource;
+    public function __construct(
+        private string $resource,
+    ) {
         $this->exists = file_exists($resource);
     }
 
diff --git a/Resource/FileResource.php b/Resource/FileResource.php
index 6e8f9bdb3..44e5bbc57 100644
--- a/Resource/FileResource.php
+++ b/Resource/FileResource.php
@@ -34,7 +34,7 @@ public function __construct(string $resource)
         $resolvedResource = realpath($resource) ?: (file_exists($resource) ? $resource : false);
 
         if (false === $resolvedResource) {
-            throw new \InvalidArgumentException(sprintf('The file "%s" does not exist.', $resource));
+            throw new \InvalidArgumentException(\sprintf('The file "%s" does not exist.', $resource));
         }
 
         $this->resource = $resolvedResource;
diff --git a/Resource/GlobResource.php b/Resource/GlobResource.php
index 2aedc84b3..e6a348e11 100644
--- a/Resource/GlobResource.php
+++ b/Resource/GlobResource.php
@@ -28,10 +28,7 @@
 class GlobResource implements \IteratorAggregate, SelfCheckingResourceInterface
 {
     private string $prefix;
-    private string $pattern;
-    private bool $recursive;
     private string $hash;
-    private bool $forExclusion;
     private array $excludedPrefixes;
     private int $globBrace;
 
@@ -42,18 +39,20 @@ class GlobResource implements \IteratorAggregate, SelfCheckingResourceInterface
      *
      * @throws \InvalidArgumentException
      */
-    public function __construct(string $prefix, string $pattern, bool $recursive, bool $forExclusion = false, array $excludedPrefixes = [])
-    {
+    public function __construct(
+        string $prefix,
+        private string $pattern,
+        private bool $recursive,
+        private bool $forExclusion = false,
+        array $excludedPrefixes = [],
+    ) {
         ksort($excludedPrefixes);
         $resolvedPrefix = realpath($prefix) ?: (file_exists($prefix) ? $prefix : false);
-        $this->pattern = $pattern;
-        $this->recursive = $recursive;
-        $this->forExclusion = $forExclusion;
         $this->excludedPrefixes = $excludedPrefixes;
         $this->globBrace = \defined('GLOB_BRACE') ? \GLOB_BRACE : 0;
 
         if (false === $resolvedPrefix) {
-            throw new \InvalidArgumentException(sprintf('The path "%s" does not exist.', $prefix));
+            throw new \InvalidArgumentException(\sprintf('The path "%s" does not exist.', $prefix));
         }
 
         $this->prefix = $resolvedPrefix;
diff --git a/Resource/ReflectionClassResource.php b/Resource/ReflectionClassResource.php
index dbd47e66d..e039329ca 100644
--- a/Resource/ReflectionClassResource.php
+++ b/Resource/ReflectionClassResource.php
@@ -12,7 +12,6 @@
 namespace Symfony\Component\Config\Resource;
 
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
-use Symfony\Component\Messenger\Handler\MessageSubscriberInterface;
 use Symfony\Contracts\Service\ServiceSubscriberInterface;
 
 /**
@@ -24,14 +23,14 @@ class ReflectionClassResource implements SelfCheckingResourceInterface
 {
     private array $files = [];
     private string $className;
-    private \ReflectionClass $classReflector;
     private array $excludedVendors = [];
     private string $hash;
 
-    public function __construct(\ReflectionClass $classReflector, array $excludedVendors = [])
-    {
+    public function __construct(
+        private \ReflectionClass $classReflector,
+        array $excludedVendors = [],
+    ) {
         $this->className = $classReflector->name;
-        $this->classReflector = $classReflector;
         $this->excludedVendors = $excludedVendors;
     }
 
@@ -82,7 +81,7 @@ private function loadFiles(\ReflectionClass $class): void
             $file = $class->getFileName();
             if (false !== $file && is_file($file)) {
                 foreach ($this->excludedVendors as $vendor) {
-                    if (str_starts_with($file, $vendor) && false !== strpbrk(substr($file, \strlen($vendor), 1), '/'.\DIRECTORY_SEPARATOR)) {
+                    if (\in_array($file[\strlen($vendor)] ?? '', ['/', \DIRECTORY_SEPARATOR], true) && str_starts_with($file, $vendor)) {
                         $file = false;
                         break;
                     }
@@ -155,6 +154,13 @@ private function generateSignature(\ReflectionClass $class): iterable
         }
 
         foreach ($class->getMethods(\ReflectionMethod::IS_PUBLIC | \ReflectionMethod::IS_PROTECTED) as $m) {
+            foreach ($this->excludedVendors as $vendor) {
+                $file = $m->getFileName();
+                if (\in_array($file[\strlen($vendor)] ?? '', ['/', \DIRECTORY_SEPARATOR], true) && str_starts_with($file, $vendor)) {
+                    continue 2;
+                }
+            }
+
             foreach ($m->getAttributes() as $a) {
                 $attributes[] = [$a->getName(), (string) $a];
             }
@@ -191,13 +197,6 @@ private function generateSignature(\ReflectionClass $class): iterable
             yield print_r($class->name::getSubscribedEvents(), true);
         }
 
-        if (interface_exists(MessageSubscriberInterface::class, false) && $class->isSubclassOf(MessageSubscriberInterface::class)) {
-            yield MessageSubscriberInterface::class;
-            foreach ($class->name::getHandledMessages() as $key => $value) {
-                yield $key.print_r($value, true);
-            }
-        }
-
         if (interface_exists(ServiceSubscriberInterface::class, false) && $class->isSubclassOf(ServiceSubscriberInterface::class)) {
             yield ServiceSubscriberInterface::class;
             yield print_r($class->name::getSubscribedServices(), true);
diff --git a/Resource/SkippingResourceChecker.php b/Resource/SkippingResourceChecker.php
new file mode 100644
index 000000000..0f0934c82
--- /dev/null
+++ b/Resource/SkippingResourceChecker.php
@@ -0,0 +1,37 @@
+<?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\Config\Resource;
+
+use Symfony\Component\Config\ResourceCheckerInterface;
+
+class SkippingResourceChecker implements ResourceCheckerInterface
+{
+    private array $skippedResourceTypes;
+
+    /**
+     * @param class-string<ResourceInterface>[] $skippedResourceTypes
+     */
+    public function __construct(array $skippedResourceTypes = [])
+    {
+        $this->skippedResourceTypes = array_flip($skippedResourceTypes);
+    }
+
+    public function supports(ResourceInterface $metadata): bool
+    {
+        return !$this->skippedResourceTypes || isset($this->skippedResourceTypes[$metadata::class]);
+    }
+
+    public function isFresh(ResourceInterface $resource, int $timestamp): bool
+    {
+        return true;
+    }
+}
diff --git a/ResourceCheckerConfigCache.php b/ResourceCheckerConfigCache.php
index 1e58d21ed..c201a3dcb 100644
--- a/ResourceCheckerConfigCache.php
+++ b/ResourceCheckerConfigCache.php
@@ -23,21 +23,19 @@
  */
 class ResourceCheckerConfigCache implements ConfigCacheInterface
 {
-    private string $file;
-
-    /**
-     * @var iterable<mixed, ResourceCheckerInterface>
-     */
-    private iterable $resourceCheckers;
+    private string $metaFile;
 
     /**
      * @param string                                    $file             The absolute cache path
      * @param iterable<mixed, ResourceCheckerInterface> $resourceCheckers The ResourceCheckers to use for the freshness check
+     * @param string|null                               $metaFile         The absolute path to the meta file, defaults to $file.meta if null
      */
-    public function __construct(string $file, iterable $resourceCheckers = [])
-    {
-        $this->file = $file;
-        $this->resourceCheckers = $resourceCheckers;
+    public function __construct(
+        private string $file,
+        private iterable $resourceCheckers = [],
+        ?string $metaFile = null,
+    ) {
+        $this->metaFile = $metaFile ?? $file.'.meta';
     }
 
     public function getPath(): string
@@ -68,7 +66,7 @@ public function isFresh(): bool
             return true; // shortcut - if we don't have any checkers we don't need to bother with the meta file at all
         }
 
-        $metadata = $this->getMetaFile();
+        $metadata = $this->metaFile;
 
         if (!is_file($metadata)) {
             return false;
@@ -105,11 +103,9 @@ public function isFresh(): bool
      * @param string              $content  The content to write in the cache
      * @param ResourceInterface[] $metadata An array of metadata
      *
-     * @return void
-     *
      * @throws \RuntimeException When cache file can't be written
      */
-    public function write(string $content, ?array $metadata = null)
+    public function write(string $content, ?array $metadata = null): void
     {
         $mode = 0666;
         $umask = umask();
@@ -122,9 +118,23 @@ public function write(string $content, ?array $metadata = null)
         }
 
         if (null !== $metadata) {
-            $filesystem->dumpFile($this->getMetaFile(), serialize($metadata));
+            $filesystem->dumpFile($this->metaFile, $ser = serialize($metadata));
+            try {
+                $filesystem->chmod($this->metaFile, $mode, $umask);
+            } catch (IOException) {
+                // discard chmod failure (some filesystem may not support it)
+            }
+
+            $ser = preg_replace_callback('/;O:(\d+):"/', static fn ($m) => ';O:'.(9 + $m[1]).':"Tracking\\', $ser);
+            $ser = preg_replace_callback('/s:(\d+):"\0[^\0]++\0/', static fn ($m) => 's:'.($m[1] - \strlen($m[0]) + 6).':"', $ser);
+            $ser = unserialize($ser);
+            $ser = @json_encode($ser) ?: [];
+            $ser = str_replace('"__PHP_Incomplete_Class_Name":"Tracking\\\\', '"@type":"', $ser);
+            $ser = \sprintf('{"resources":%s}', $ser);
+
+            $filesystem->dumpFile($this->metaFile.'.json', $ser);
             try {
-                $filesystem->chmod($this->getMetaFile(), $mode, $umask);
+                $filesystem->chmod($this->metaFile.'.json', $mode, $umask);
             } catch (IOException) {
                 // discard chmod failure (some filesystem may not support it)
             }
@@ -135,18 +145,10 @@ public function write(string $content, ?array $metadata = null)
         }
     }
 
-    /**
-     * Gets the meta file path.
-     */
-    private function getMetaFile(): string
-    {
-        return $this->file.'.meta';
-    }
-
     private function safelyUnserialize(string $file): mixed
     {
         $meta = false;
-        $content = file_get_contents($file);
+        $content = (new Filesystem())->readFile($file);
         $signalingException = new \UnexpectedValueException();
         $prevUnserializeHandler = ini_set('unserialize_callback_func', self::class.'::handleUnserializeCallback');
         $prevErrorHandler = set_error_handler(function ($type, $msg, $file, $line, $context = []) use (&$prevErrorHandler, $signalingException) {
diff --git a/ResourceCheckerConfigCacheFactory.php b/ResourceCheckerConfigCacheFactory.php
index 97d52006f..595855ccb 100644
--- a/ResourceCheckerConfigCacheFactory.php
+++ b/ResourceCheckerConfigCacheFactory.php
@@ -19,14 +19,12 @@
  */
 class ResourceCheckerConfigCacheFactory implements ConfigCacheFactoryInterface
 {
-    private iterable $resourceCheckers = [];
-
     /**
      * @param iterable<int, ResourceCheckerInterface> $resourceCheckers
      */
-    public function __construct(iterable $resourceCheckers = [])
-    {
-        $this->resourceCheckers = $resourceCheckers;
+    public function __construct(
+        private iterable $resourceCheckers = [],
+    ) {
     }
 
     public function cache(string $file, callable $callable): ConfigCacheInterface
diff --git a/ResourceCheckerInterface.php b/ResourceCheckerInterface.php
index 6b1c6c5fb..13ae03f45 100644
--- a/ResourceCheckerInterface.php
+++ b/ResourceCheckerInterface.php
@@ -29,17 +29,13 @@ interface ResourceCheckerInterface
     /**
      * Queries the ResourceChecker whether it can validate a given
      * resource or not.
-     *
-     * @return bool
      */
-    public function supports(ResourceInterface $metadata);
+    public function supports(ResourceInterface $metadata): bool;
 
     /**
      * Validates the resource.
      *
      * @param int $timestamp The timestamp at which the cache associated with this resource was created
-     *
-     * @return bool
      */
-    public function isFresh(ResourceInterface $resource, int $timestamp);
+    public function isFresh(ResourceInterface $resource, int $timestamp): bool;
 }
diff --git a/Tests/Builder/GeneratedConfigTest.php b/Tests/Builder/GeneratedConfigTest.php
index 722df54cb..680010f00 100644
--- a/Tests/Builder/GeneratedConfigTest.php
+++ b/Tests/Builder/GeneratedConfigTest.php
@@ -40,8 +40,6 @@ class GeneratedConfigTest extends TestCase
 
     protected function setup(): void
     {
-        parent::setup();
-
         $this->tempDir = [];
     }
 
@@ -49,8 +47,6 @@ protected function tearDown(): void
     {
         (new Filesystem())->remove($this->tempDir);
         $this->tempDir = [];
-
-        parent::tearDown();
     }
 
     public static function fixtureNames()
@@ -92,7 +88,6 @@ public function testConfig(string $name, string $alias)
         // $this->generateConfigBuilder('Symfony\\Component\\Config\\Tests\\Builder\\Fixtures\\'.$name, $expectedCode);
         // $this->markTestIncomplete('Re-comment the line above and relaunch the tests');
 
-        $outputDir = sys_get_temp_dir().\DIRECTORY_SEPARATOR.uniqid('sf_config_builder', true);
         $configBuilder = $this->generateConfigBuilder('Symfony\\Component\\Config\\Tests\\Builder\\Fixtures\\'.$name, $outputDir);
         $callback($configBuilder);
 
@@ -162,12 +157,12 @@ public function testSetExtraKeyMethodIsNotGeneratedWhenAllowExtraKeysIsFalse()
     /**
      * Generate the ConfigBuilder or return an already generated instance.
      */
-    private function generateConfigBuilder(string $configurationClass, ?string $outputDir = null)
+    private function generateConfigBuilder(string $configurationClass, ?string &$outputDir = null)
     {
-        $outputDir ??= sys_get_temp_dir().\DIRECTORY_SEPARATOR.uniqid('sf_config_builder', true);
-        if (!str_contains($outputDir, __DIR__)) {
-            $this->tempDir[] = $outputDir;
-        }
+        $outputDir = tempnam(sys_get_temp_dir(), 'sf_config_builder_');
+        unlink($outputDir);
+        mkdir($outputDir);
+        $this->tempDir[] = $outputDir;
 
         $configuration = new $configurationClass();
         $rootNode = $configuration->getConfigTreeBuilder()->buildTree();
diff --git a/Tests/ConfigCacheTest.php b/Tests/ConfigCacheTest.php
index f4ead1d52..e639fb220 100644
--- a/Tests/ConfigCacheTest.php
+++ b/Tests/ConfigCacheTest.php
@@ -13,21 +13,24 @@
 
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\Config\ConfigCache;
+use Symfony\Component\Config\Resource\FileResource;
 use Symfony\Component\Config\Resource\SelfCheckingResourceChecker;
 use Symfony\Component\Config\Tests\Resource\ResourceStub;
 
 class ConfigCacheTest extends TestCase
 {
     private string $cacheFile;
+    private string $metaFile;
 
     protected function setUp(): void
     {
         $this->cacheFile = tempnam(sys_get_temp_dir(), 'config_');
+        $this->metaFile = tempnam(sys_get_temp_dir(), 'config_');
     }
 
     protected function tearDown(): void
     {
-        $files = [$this->cacheFile, $this->cacheFile.'.meta'];
+        $files = [$this->cacheFile, $this->cacheFile.'.meta', $this->metaFile];
 
         foreach ($files as $file) {
             if (file_exists($file)) {
@@ -103,4 +106,14 @@ public static function debugModes(): array
             [false],
         ];
     }
+
+    public function testCacheWithCustomMetaFile()
+    {
+        $this->assertStringEqualsFile($this->metaFile, '');
+
+        $cache = new ConfigCache($this->cacheFile, false, $this->metaFile);
+        $cache->write('foo', [new FileResource(__FILE__)]);
+
+        $this->assertStringNotEqualsFile($this->metaFile, '');
+    }
 }
diff --git a/Tests/Definition/BooleanNodeTest.php b/Tests/Definition/BooleanNodeTest.php
index f617148ff..9358a975d 100644
--- a/Tests/Definition/BooleanNodeTest.php
+++ b/Tests/Definition/BooleanNodeTest.php
@@ -26,6 +26,33 @@ public function testNormalize(bool $value)
         $this->assertSame($value, $node->normalize($value));
     }
 
+    public function testNullValueOnNullable()
+    {
+        $node = new BooleanNode('test', null, '.', true);
+
+        $this->assertNull($node->normalize(null));
+    }
+
+    public function testNullValueOnNotNullable()
+    {
+        $node = new BooleanNode('test', null, '.', false);
+
+        $this->expectException(InvalidTypeException::class);
+        $this->expectExceptionMessage('Invalid type for path "test". Expected "bool", but got "null".');
+
+        $this->assertNull($node->normalize(null));
+    }
+
+    public function testInvalidValueOnNullable()
+    {
+        $node = new BooleanNode('test', null, '.', true);
+
+        $this->expectException(InvalidTypeException::class);
+        $this->expectExceptionMessage('Invalid type for path "test". Expected "bool" or "null", but got "int".');
+
+        $node->normalize(123);
+    }
+
     /**
      * @dataProvider getValidValues
      */
@@ -50,7 +77,6 @@ public static function getValidValues(): array
      */
     public function testNormalizeThrowsExceptionOnInvalidValues($value)
     {
-
         $node = new BooleanNode('test');
 
         $this->expectException(InvalidTypeException::class);
@@ -61,7 +87,6 @@ public function testNormalizeThrowsExceptionOnInvalidValues($value)
     public static function getInvalidValues(): array
     {
         return [
-            [null],
             [''],
             ['foo'],
             [0],
diff --git a/Tests/Definition/Builder/ArrayNodeDefinitionTest.php b/Tests/Definition/Builder/ArrayNodeDefinitionTest.php
index b91faf17c..ca376ea8a 100644
--- a/Tests/Definition/Builder/ArrayNodeDefinitionTest.php
+++ b/Tests/Definition/Builder/ArrayNodeDefinitionTest.php
@@ -239,7 +239,7 @@ public function testUnsetChild()
             ->children()
                 ->scalarNode('value')
                     ->beforeNormalization()
-                        ->ifTrue(fn ($value) => empty($value))
+                        ->ifTrue(fn ($value) => !$value)
                         ->thenUnset()
                     ->end()
                 ->end()
@@ -267,6 +267,12 @@ public function testPrototypeBoolean()
         $this->assertEquals($node->prototype('boolean'), $node->booleanPrototype());
     }
 
+    public function testPrototypeString()
+    {
+        $node = new ArrayNodeDefinition('root');
+        $this->assertEquals($node->prototype('string'), $node->stringPrototype());
+    }
+
     public function testPrototypeInteger()
     {
         $node = new ArrayNodeDefinition('root');
diff --git a/Tests/Definition/Builder/BooleanNodeDefinitionTest.php b/Tests/Definition/Builder/BooleanNodeDefinitionTest.php
index 7a4706a3e..67b3aaf64 100644
--- a/Tests/Definition/Builder/BooleanNodeDefinitionTest.php
+++ b/Tests/Definition/Builder/BooleanNodeDefinitionTest.php
@@ -25,6 +25,30 @@ public function testCannotBeEmptyThrowsAnException()
         $def->cannotBeEmpty();
     }
 
+    public function testBooleanNodeWithDefaultNull()
+    {
+        $def = new BooleanNodeDefinition('foo');
+        $def->defaultNull();
+
+        $node = $def->getNode();
+        $this->assertTrue($node->hasDefaultValue());
+        $this->assertNull($node->getDefaultValue());
+
+        $this->assertNull($node->normalize(null));
+    }
+
+    public function testBooleanNodeWithDefaultValueAtNull()
+    {
+        $def = new BooleanNodeDefinition('foo');
+        $def->defaultValue(null);
+
+        $node = $def->getNode();
+        $this->assertTrue($node->hasDefaultValue());
+        $this->assertNull($node->getDefaultValue());
+
+        $this->assertNull($node->normalize(null));
+    }
+
     public function testSetDeprecated()
     {
         $def = new BooleanNodeDefinition('foo');
diff --git a/Tests/Definition/Builder/NodeBuilderTest.php b/Tests/Definition/Builder/NodeBuilderTest.php
index 1338c58a6..bee64388c 100644
--- a/Tests/Definition/Builder/NodeBuilderTest.php
+++ b/Tests/Definition/Builder/NodeBuilderTest.php
@@ -15,6 +15,7 @@
 use Symfony\Component\Config\Definition\Builder\FloatNodeDefinition;
 use Symfony\Component\Config\Definition\Builder\IntegerNodeDefinition;
 use Symfony\Component\Config\Definition\Builder\NodeBuilder as BaseNodeBuilder;
+use Symfony\Component\Config\Definition\Builder\StringNodeDefinition;
 use Symfony\Component\Config\Definition\Builder\VariableNodeDefinition as BaseVariableNodeDefinition;
 
 class NodeBuilderTest extends TestCase
@@ -86,6 +87,14 @@ public function testNumericNodeCreation()
         $node = $builder->floatNode('bar')->min(3.0)->max(5.0);
         $this->assertInstanceOf(FloatNodeDefinition::class, $node);
     }
+
+    public function testStringNodeCreation()
+    {
+        $builder = new BaseNodeBuilder();
+
+        $node = $builder->stringNode('foo bar');
+        $this->assertInstanceOf(StringNodeDefinition::class, $node);
+    }
 }
 
 class SomeNodeDefinition extends BaseVariableNodeDefinition
diff --git a/Tests/Definition/PrototypedArrayNodeTest.php b/Tests/Definition/PrototypedArrayNodeTest.php
index abf0de777..f1868a04a 100644
--- a/Tests/Definition/PrototypedArrayNodeTest.php
+++ b/Tests/Definition/PrototypedArrayNodeTest.php
@@ -291,51 +291,51 @@ public static function getDataForKeyRemovedLeftValueOnly(): array
         $variableValue = new VariableNode('value');
 
         return [
-           [
-               $scalarValue,
-               [
-                   ['id' => 'option1', 'value' => 'value1'],
-               ],
-               ['option1' => 'value1'],
-           ],
-
-           [
-               $scalarValue,
-               [
-                   ['id' => 'option1', 'value' => 'value1'],
-                   ['id' => 'option2', 'value' => 'value2', 'foo' => 'foo2'],
-               ],
-               [
-                   'option1' => 'value1',
-                   'option2' => ['value' => 'value2', 'foo' => 'foo2'],
-               ],
-           ],
-
-           [
-               $arrayValue,
-               [
-                   [
-                       'id' => 'option1',
-                       'value' => ['foo' => 'foo1', 'bar' => 'bar1'],
-                   ],
-               ],
-               [
-                   'option1' => ['foo' => 'foo1', 'bar' => 'bar1'],
-               ],
-           ],
-
-           [$variableValue,
-               [
-                   [
-                       'id' => 'option1', 'value' => ['foo' => 'foo1', 'bar' => 'bar1'],
-                   ],
-                   ['id' => 'option2', 'value' => 'value2'],
-               ],
-               [
-                   'option1' => ['foo' => 'foo1', 'bar' => 'bar1'],
-                   'option2' => 'value2',
-               ],
-           ],
+            [
+                $scalarValue,
+                [
+                    ['id' => 'option1', 'value' => 'value1'],
+                ],
+                ['option1' => 'value1'],
+            ],
+
+            [
+                $scalarValue,
+                [
+                    ['id' => 'option1', 'value' => 'value1'],
+                    ['id' => 'option2', 'value' => 'value2', 'foo' => 'foo2'],
+                ],
+                [
+                    'option1' => 'value1',
+                    'option2' => ['value' => 'value2', 'foo' => 'foo2'],
+                ],
+            ],
+
+            [
+                $arrayValue,
+                [
+                    [
+                        'id' => 'option1',
+                        'value' => ['foo' => 'foo1', 'bar' => 'bar1'],
+                    ],
+                ],
+                [
+                    'option1' => ['foo' => 'foo1', 'bar' => 'bar1'],
+                ],
+            ],
+
+            [$variableValue,
+                [
+                    [
+                        'id' => 'option1', 'value' => ['foo' => 'foo1', 'bar' => 'bar1'],
+                    ],
+                    ['id' => 'option2', 'value' => 'value2'],
+                ],
+                [
+                    'option1' => ['foo' => 'foo1', 'bar' => 'bar1'],
+                    'option2' => 'value2',
+                ],
+            ],
         ];
     }
 
diff --git a/Tests/Definition/ScalarNodeTest.php b/Tests/Definition/ScalarNodeTest.php
index eea3d49b4..9ccd910c2 100644
--- a/Tests/Definition/ScalarNodeTest.php
+++ b/Tests/Definition/ScalarNodeTest.php
@@ -127,8 +127,6 @@ public function testNormalizeThrowsExceptionWithErrorMessage()
 
     /**
      * @dataProvider getValidNonEmptyValues
-     *
-     * @param mixed $value
      */
     public function testValidNonEmptyValues($value)
     {
diff --git a/Tests/Definition/StringNodeTest.php b/Tests/Definition/StringNodeTest.php
new file mode 100644
index 000000000..ddc219d24
--- /dev/null
+++ b/Tests/Definition/StringNodeTest.php
@@ -0,0 +1,49 @@
+<?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\Config\Tests\Definition;
+
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\Config\Definition\Exception\InvalidTypeException;
+use Symfony\Component\Config\Definition\StringNode;
+
+class StringNodeTest extends TestCase
+{
+    /**
+     * @testWith [""]
+     *           ["valid string"]
+     */
+    public function testNormalize(string $value)
+    {
+        $node = new StringNode('test');
+        $this->assertSame($value, $node->normalize($value));
+    }
+
+    /**
+     * @testWith [null]
+     *           [false]
+     *           [true]
+     *           [0]
+     *           [1]
+     *           [0.0]
+     *           [0.1]
+     *           [{}]
+     *           [{"foo": "bar"}]
+     */
+    public function testNormalizeThrowsExceptionOnInvalidValues($value)
+    {
+        $node = new StringNode('test');
+
+        $this->expectException(InvalidTypeException::class);
+
+        $node->normalize($value);
+    }
+}
diff --git a/Tests/FileLocatorTest.php b/Tests/FileLocatorTest.php
index d042bff7d..beb005a35 100644
--- a/Tests/FileLocatorTest.php
+++ b/Tests/FileLocatorTest.php
@@ -38,6 +38,7 @@ public static function getIsAbsolutePathTests(): array
             ['\\server\\foo.xml'],
             ['https://server/foo.xml'],
             ['phar://server/foo.xml'],
+            ['phar:///server/foo.xml'],
         ];
     }
 
diff --git a/Tests/Loader/LoaderTest.php b/Tests/Loader/LoaderTest.php
index 70bfb8fc1..263bde26d 100644
--- a/Tests/Loader/LoaderTest.php
+++ b/Tests/Loader/LoaderTest.php
@@ -13,6 +13,7 @@
 
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\Config\Exception\LoaderLoadException;
+use Symfony\Component\Config\Exception\LogicException;
 use Symfony\Component\Config\Loader\Loader;
 use Symfony\Component\Config\Loader\LoaderInterface;
 use Symfony\Component\Config\Loader\LoaderResolverInterface;
@@ -29,6 +30,14 @@ public function testGetSetResolver()
         $this->assertSame($resolver, $loader->getResolver(), '->setResolver() sets the resolver loader');
     }
 
+    public function testGetResolverWithoutSetResolver()
+    {
+        $this->expectException(LogicException::class);
+
+        $loader = new ProjectLoader1();
+        $loader->getResolver();
+    }
+
     public function testResolve()
     {
         $resolvedLoader = $this->createMock(LoaderInterface::class);
@@ -46,6 +55,14 @@ public function testResolve()
         $this->assertSame($resolvedLoader, $loader->resolve('foo.xml'), '->resolve() finds a loader');
     }
 
+    public function testResolveWithoutSetResolver()
+    {
+        $this->expectException(LoaderLoadException::class);
+
+        $loader = new ProjectLoader1();
+        $loader->resolve('foo.xml');
+    }
+
     public function testResolveWhenResolverCannotFindLoader()
     {
         $resolver = $this->createMock(LoaderResolverInterface::class);
diff --git a/Tests/Resource/GlobResourceTest.php b/Tests/Resource/GlobResourceTest.php
index 4d1eb4f1f..c2698b033 100644
--- a/Tests/Resource/GlobResourceTest.php
+++ b/Tests/Resource/GlobResourceTest.php
@@ -41,7 +41,6 @@ public function testIterator()
 
         $paths = iterator_to_array($resource);
 
-        $file = $dir.'/Resource'.\DIRECTORY_SEPARATOR.'ConditionalClass.php';
         $this->assertEquals([$file => $file], $paths);
         $this->assertInstanceOf(\SplFileInfo::class, current($paths));
         $this->assertSame($dir, $resource->getPrefix());
diff --git a/Tests/Resource/ReflectionClassResourceTest.php b/Tests/Resource/ReflectionClassResourceTest.php
index be2c075fc..e7e36a063 100644
--- a/Tests/Resource/ReflectionClassResourceTest.php
+++ b/Tests/Resource/ReflectionClassResourceTest.php
@@ -14,7 +14,6 @@
 use PHPUnit\Framework\TestCase;
 use Symfony\Component\Config\Resource\ReflectionClassResource;
 use Symfony\Component\EventDispatcher\EventSubscriberInterface;
-use Symfony\Component\Messenger\Handler\MessageSubscriberInterface;
 use Symfony\Contracts\Service\ServiceSubscriberInterface;
 
 class ReflectionClassResourceTest extends TestCase
@@ -64,7 +63,7 @@ public function testIsFreshForDeletedResources()
     /**
      * @dataProvider provideHashedSignature
      */
-    public function testHashedSignature(bool $changeExpected, int $changedLine, ?string $changedCode, ?\Closure $setContext = null)
+    public function testHashedSignature(bool $changeExpected, int $changedLine, ?string $changedCode, int $resourceClassNameSuffix, ?\Closure $setContext = null)
     {
         if ($setContext) {
             $setContext();
@@ -95,7 +94,7 @@ public function testHashedSignature(bool $changeExpected, int $changedLine, ?str
         static $expectedSignature, $generateSignature;
 
         if (null === $expectedSignature) {
-            eval(sprintf($code, $class = 'Foo'.str_replace('.', '_', uniqid('', true))));
+            eval(\sprintf($code, $class = 'Foo'.(string) $resourceClassNameSuffix));
             $r = new \ReflectionClass(ReflectionClassResource::class);
             $generateSignature = $r->getMethod('generateSignature');
             $generateSignature = $generateSignature->getClosure($r->newInstanceWithoutConstructor());
@@ -106,7 +105,7 @@ public function testHashedSignature(bool $changeExpected, int $changedLine, ?str
         if (null !== $changedCode) {
             $code[$changedLine] = $changedCode;
         }
-        eval(sprintf(implode("\n", $code), $class = 'Foo'.str_replace('.', '_', uniqid('', true))));
+        eval(\sprintf(implode("\n", $code), $class = 'Bar'.(string) $resourceClassNameSuffix));
         $signature = implode("\n", iterator_to_array($generateSignature(new \ReflectionClass($class))));
 
         if ($changeExpected) {
@@ -118,49 +117,50 @@ public function testHashedSignature(bool $changeExpected, int $changedLine, ?str
 
     public static function provideHashedSignature(): iterable
     {
-        yield [false, 0, "// line change\n\n"];
-        yield [true, 0, '/** class docblock */'];
-        yield [true, 0, '#[Foo]'];
-        yield [true, 0, '#[Foo(new MissingClass)]'];
-        yield [true, 1, 'abstract class %s'];
-        yield [true, 1, 'final class %s'];
-        yield [true, 1, 'class %s extends Exception'];
-        yield [true, 1, 'class %s implements '.DummyInterface::class];
-        yield [true, 3, 'const FOO = 456;'];
-        yield [true, 3, 'const BAR = 123;'];
-        yield [true, 4, '/** pub docblock */'];
-        yield [true, 5, 'protected $pub = [];'];
-        yield [true, 5, 'public $pub = [123];'];
-        yield [true, 5, '#[Foo(new MissingClass)] public $pub = [];'];
-        yield [true, 6, '/** prot docblock */'];
-        yield [true, 7, 'private $prot;'];
-        yield [false, 8, '/** priv docblock */'];
-        yield [false, 9, 'private $priv = 123;'];
-        yield [true, 10, '/** pub docblock */'];
-        yield [true, 11, 'public function pub(...$arg) {}'];
-        yield [true, 11, 'public function pub($arg = null): Foo {}'];
-        yield [false, 11, "public function pub(\$arg = null) {\nreturn 123;\n}"];
-        yield [true, 12, '/** prot docblock */'];
-        yield [true, 13, 'protected function prot($a = [123]) {}'];
-        yield [true, 13, '#[Foo] protected function prot($a = []) {}'];
-        yield [true, 13, 'protected function prot(#[Foo] $a = []) {}'];
-        yield [true, 13, '#[Foo(new MissingClass)] protected function prot($a = []) {}'];
-        yield [true, 13, 'protected function prot(#[Foo(new MissingClass)] $a = []) {}'];
-        yield [false, 14, '/** priv docblock */'];
-        yield [false, 15, ''];
+        $i = 0;
+        yield [false, 0, "// line change\n\n", ++$i];
+        yield [true, 0, '/** class docblock */', ++$i];
+        yield [true, 0, '#[Foo]', ++$i];
+        yield [true, 0, '#[Foo(new MissingClass)]', ++$i];
+        yield [true, 1, 'abstract class %s', ++$i];
+        yield [true, 1, 'final class %s', ++$i];
+        yield [true, 1, 'class %s extends Exception', ++$i];
+        yield [true, 1, 'class %s implements '.DummyInterface::class, ++$i];
+        yield [true, 3, 'const FOO = 456;', ++$i];
+        yield [true, 3, 'const BAR = 123;', ++$i];
+        yield [true, 4, '/** pub docblock */', ++$i];
+        yield [true, 5, 'protected $pub = [];', ++$i];
+        yield [true, 5, 'public $pub = [123];', ++$i];
+        yield [true, 5, '#[Foo(new MissingClass)] public $pub = [];', ++$i];
+        yield [true, 6, '/** prot docblock */', ++$i];
+        yield [true, 7, 'private $prot;', ++$i];
+        yield [false, 8, '/** priv docblock */', ++$i];
+        yield [false, 9, 'private $priv = 123;', ++$i];
+        yield [true, 10, '/** pub docblock */', ++$i];
+        yield [true, 11, 'public function pub(...$arg) {}', ++$i];
+        yield [true, 11, 'public function pub($arg = null): Foo {}', ++$i];
+        yield [false, 11, "public function pub(\$arg = null) {\nreturn 123;\n}", ++$i];
+        yield [true, 12, '/** prot docblock */', ++$i];
+        yield [true, 13, 'protected function prot($a = [123]) {}', ++$i];
+        yield [true, 13, '#[Foo] protected function prot($a = []) {}', ++$i];
+        yield [true, 13, 'protected function prot(#[Foo] $a = []) {}', ++$i];
+        yield [true, 13, '#[Foo(new MissingClass)] protected function prot($a = []) {}', ++$i];
+        yield [true, 13, 'protected function prot(#[Foo(new MissingClass)] $a = []) {}', ++$i];
+        yield [false, 14, '/** priv docblock */', ++$i];
+        yield [false, 15, null, ++$i];
 
         // PHP7.4 typed properties without default value are
         // undefined, make sure this doesn't throw an error
-        yield [true, 5, 'public array $pub;'];
-        yield [false, 7, 'protected int $prot;'];
-        yield [false, 9, 'private string $priv;'];
-        yield [true, 17, 'public function __construct(private $bar = new \stdClass()) {}'];
-        yield [true, 17, 'public function ccc($bar = new \stdClass()) {}'];
-        yield [true, 17, 'public function ccc($bar = new MissingClass()) {}'];
-        yield [true, 17, 'public function ccc($bar = 187) {}'];
-        yield [true, 17, 'public function ccc($bar = ANOTHER_ONE_THAT_WILL_NEVER_BE_DEFINED_CCCCCCCCC) {}'];
-        yield [true, 17, 'public function ccc($bar = parent::BOOM) {}'];
-        yield [false, 17, null, static function () { \define('A_CONSTANT_THAT_FOR_SURE_WILL_NEVER_BE_DEFINED_CCCCCC', 'foo'); }];
+        yield [true, 5, 'public array $pub;', ++$i];
+        yield [false, 7, 'protected int $prot;', ++$i];
+        yield [false, 9, 'private string $priv;', ++$i];
+        yield [true, 17, 'public function __construct(private $bar = new \stdClass()) {}', ++$i];
+        yield [true, 17, 'public function ccc($bar = new \stdClass()) {}', ++$i];
+        yield [true, 17, 'public function ccc($bar = new MissingClass()) {}', ++$i];
+        yield [true, 17, 'public function ccc($bar = 187) {}', ++$i];
+        yield [true, 17, 'public function ccc($bar = ANOTHER_ONE_THAT_WILL_NEVER_BE_DEFINED_CCCCCCCCC) {}', ++$i];
+        yield [true, 17, 'public function ccc($bar = parent::BOOM) {}', ++$i];
+        yield [false, 17, null, ++$i, static function () { \define('A_CONSTANT_THAT_FOR_SURE_WILL_NEVER_BE_DEFINED_CCCCCC', 'foo'); }];
     }
 
     public function testEventSubscriber()
@@ -175,27 +175,6 @@ public function testEventSubscriber()
         $this->assertTrue($res->isFresh(0));
     }
 
-    /**
-     * @group legacy
-     */
-    public function testMessageSubscriber()
-    {
-        $res = new ReflectionClassResource(new \ReflectionClass(TestMessageSubscriber::class));
-        $this->assertTrue($res->isFresh(0));
-
-        TestMessageSubscriberConfigHolder::$handledMessages = ['SomeMessageClass' => []];
-        $this->assertFalse($res->isFresh(0));
-
-        $res = new ReflectionClassResource(new \ReflectionClass(TestMessageSubscriber::class));
-        $this->assertTrue($res->isFresh(0));
-
-        TestMessageSubscriberConfigHolder::$handledMessages = ['OtherMessageClass' => []];
-        $this->assertFalse($res->isFresh(0));
-
-        $res = new ReflectionClassResource(new \ReflectionClass(TestMessageSubscriber::class));
-        $this->assertTrue($res->isFresh(0));
-    }
-
     public function testServiceSubscriber()
     {
         $res = new ReflectionClassResource(new \ReflectionClass(TestServiceSubscriber::class));
@@ -232,22 +211,6 @@ public static function getSubscribedEvents(): array
     }
 }
 
-if (interface_exists(MessageSubscriberInterface::class)) {
-    class TestMessageSubscriber implements MessageSubscriberInterface
-    {
-        public static function getHandledMessages(): iterable
-        {
-            foreach (TestMessageSubscriberConfigHolder::$handledMessages as $key => $subscribedMessage) {
-                yield $key => $subscribedMessage;
-            }
-        }
-    }
-    class TestMessageSubscriberConfigHolder
-    {
-        public static array $handledMessages = [];
-    }
-}
-
 class TestServiceSubscriber implements ServiceSubscriberInterface
 {
     public static array $subscribedServices = [];
diff --git a/Tests/ResourceCheckerConfigCacheTest.php b/Tests/ResourceCheckerConfigCacheTest.php
index 37f30a49d..3dbbe4334 100644
--- a/Tests/ResourceCheckerConfigCacheTest.php
+++ b/Tests/ResourceCheckerConfigCacheTest.php
@@ -20,15 +20,17 @@
 class ResourceCheckerConfigCacheTest extends TestCase
 {
     private string $cacheFile;
+    private string $metaFile;
 
     protected function setUp(): void
     {
         $this->cacheFile = tempnam(sys_get_temp_dir(), 'config_');
+        $this->metaFile = tempnam(sys_get_temp_dir(), 'config_');
     }
 
     protected function tearDown(): void
     {
-        $files = [$this->cacheFile, "{$this->cacheFile}.meta"];
+        $files = [$this->cacheFile, $this->cacheFile.'.meta', $this->cacheFile.'.meta.json', $this->metaFile, $this->metaFile.'.json'];
 
         foreach ($files as $file) {
             if (file_exists($file)) {
@@ -148,4 +150,24 @@ public function testCacheIsNotFreshIfNotExistsMetaFile()
 
         $this->assertFalse($cache->isFresh());
     }
+
+    public function testCacheWithCustomMetaFile()
+    {
+        $this->assertStringEqualsFile($this->metaFile, '');
+
+        $checker = $this->createMock(ResourceCheckerInterface::class);
+        $cache = new ResourceCheckerConfigCache($this->cacheFile, [$checker], $this->metaFile);
+        $cache->write('foo', [new FileResource(__FILE__)]);
+
+        $this->assertStringNotEqualsFile($this->metaFile, '');
+
+        $this->assertStringEqualsFile($this->metaFile.'.json', json_encode([
+            'resources' => [
+                [
+                    '@type' => FileResource::class,
+                    'resource' => __FILE__,
+                ],
+            ],
+        ]));
+    }
 }
diff --git a/Tests/Util/XmlUtilsTest.php b/Tests/Util/XmlUtilsTest.php
index 89f1014aa..2bc31e3bb 100644
--- a/Tests/Util/XmlUtilsTest.php
+++ b/Tests/Util/XmlUtilsTest.php
@@ -196,7 +196,7 @@ public function testLoadEmptyXmlFile()
         $file = __DIR__.'/../Fixtures/foo.xml';
 
         $this->expectException(\InvalidArgumentException::class);
-        $this->expectExceptionMessage(sprintf('File "%s" does not contain valid XML, it is empty.', $file));
+        $this->expectExceptionMessage(\sprintf('File "%s" does not contain valid XML, it is empty.', $file));
 
         XmlUtils::loadFile($file);
     }
@@ -216,7 +216,7 @@ public function testLoadWrongEmptyXMLWithErrorHandler()
                 XmlUtils::loadFile($file);
                 $this->fail('An exception should have been raised');
             } catch (\InvalidArgumentException $e) {
-                $this->assertEquals(sprintf('File "%s" does not contain valid XML, it is empty.', $file), $e->getMessage());
+                $this->assertEquals(\sprintf('File "%s" does not contain valid XML, it is empty.', $file), $e->getMessage());
             }
         } finally {
             restore_error_handler();
diff --git a/Util/XmlUtils.php b/Util/XmlUtils.php
index eb6f0f51a..02ebe7dbe 100644
--- a/Util/XmlUtils.php
+++ b/Util/XmlUtils.php
@@ -13,6 +13,7 @@
 
 use Symfony\Component\Config\Util\Exception\InvalidXmlException;
 use Symfony\Component\Config\Util\Exception\XmlParsingException;
+use Symfony\Component\Filesystem\Filesystem;
 
 /**
  * XMLUtils is a bunch of utility methods to XML operations.
@@ -79,12 +80,12 @@ public static function parse(string $content, string|callable|null $schemaOrCall
                     $valid = false;
                 }
             } elseif (is_file($schemaOrCallable)) {
-                $schemaSource = file_get_contents((string) $schemaOrCallable);
+                $schemaSource = (new Filesystem())->readFile($schemaOrCallable);
                 $valid = @$dom->schemaValidateSource($schemaSource);
             } else {
                 libxml_use_internal_errors($internalErrors);
 
-                throw new XmlParsingException(sprintf('Invalid XSD file: "%s".', $schemaOrCallable));
+                throw new XmlParsingException(\sprintf('Invalid XSD file: "%s".', $schemaOrCallable));
             }
 
             if (!$valid) {
@@ -115,23 +116,23 @@ public static function parse(string $content, string|callable|null $schemaOrCall
     public static function loadFile(string $file, string|callable|null $schemaOrCallable = null): \DOMDocument
     {
         if (!is_file($file)) {
-            throw new \InvalidArgumentException(sprintf('Resource "%s" is not a file.', $file));
+            throw new \InvalidArgumentException(\sprintf('Resource "%s" is not a file.', $file));
         }
 
         if (!is_readable($file)) {
-            throw new \InvalidArgumentException(sprintf('File "%s" is not readable.', $file));
+            throw new \InvalidArgumentException(\sprintf('File "%s" is not readable.', $file));
         }
 
-        $content = @file_get_contents($file);
+        $content = (new Filesystem())->readFile($file);
 
         if ('' === trim($content)) {
-            throw new \InvalidArgumentException(sprintf('File "%s" does not contain valid XML, it is empty.', $file));
+            throw new \InvalidArgumentException(\sprintf('File "%s" does not contain valid XML, it is empty.', $file));
         }
 
         try {
             return static::parse($content, $schemaOrCallable);
         } catch (InvalidXmlException $e) {
-            throw new XmlParsingException(sprintf('The XML file "%s" is not valid.', $file), 0, $e->getPrevious());
+            throw new XmlParsingException(\sprintf('The XML file "%s" is not valid.', $file), 0, $e->getPrevious());
         }
     }
 
@@ -155,7 +156,7 @@ public static function loadFile(string $file, string|callable|null $schemaOrCall
      */
     public static function convertDomElementToArray(\DOMElement $element, bool $checkPrefix = true): mixed
     {
-        $prefix = (string) $element->prefix;
+        $prefix = $element->prefix;
         $empty = true;
         $config = [];
         foreach ($element->attributes as $name => $node) {
@@ -173,7 +174,7 @@ public static function convertDomElementToArray(\DOMElement $element, bool $chec
                     $nodeValue = trim($node->nodeValue);
                     $empty = false;
                 }
-            } elseif ($checkPrefix && $prefix != (string) $node->prefix) {
+            } elseif ($checkPrefix && $prefix != $node->prefix) {
                 continue;
             } elseif (!$node instanceof \DOMComment) {
                 $value = static::convertDomElementToArray($node, $checkPrefix);
@@ -238,14 +239,11 @@ public static function phpize(string|\Stringable $value): mixed
         }
     }
 
-    /**
-     * @return array
-     */
-    protected static function getXmlErrors(bool $internalErrors)
+    protected static function getXmlErrors(bool $internalErrors): array
     {
         $errors = [];
         foreach (libxml_get_errors() as $error) {
-            $errors[] = sprintf('[%s %s] %s (in %s - line %d, column %d)',
+            $errors[] = \sprintf('[%s %s] %s (in %s - line %d, column %d)',
                 \LIBXML_ERR_WARNING == $error->level ? 'WARNING' : 'ERROR',
                 $error->code,
                 trim($error->message),
diff --git a/composer.json b/composer.json
index dbd34f13b..37206042a 100644
--- a/composer.json
+++ b/composer.json
@@ -16,20 +16,20 @@
         }
     ],
     "require": {
-        "php": ">=8.1",
+        "php": ">=8.2",
         "symfony/deprecation-contracts": "^2.5|^3",
-        "symfony/filesystem": "^5.4|^6.0|^7.0",
+        "symfony/filesystem": "^7.1",
         "symfony/polyfill-ctype": "~1.8"
     },
     "require-dev": {
-        "symfony/event-dispatcher": "^5.4|^6.0|^7.0",
-        "symfony/finder": "^5.4|^6.0|^7.0",
-        "symfony/messenger": "^5.4|^6.0|^7.0",
+        "symfony/event-dispatcher": "^6.4|^7.0",
+        "symfony/finder": "^6.4|^7.0",
+        "symfony/messenger": "^6.4|^7.0",
         "symfony/service-contracts": "^2.5|^3",
-        "symfony/yaml": "^5.4|^6.0|^7.0"
+        "symfony/yaml": "^6.4|^7.0"
     },
     "conflict": {
-        "symfony/finder": "<5.4",
+        "symfony/finder": "<6.4",
         "symfony/service-contracts": "<2.5"
     },
     "autoload": {