diff --git a/.php-cs-fixer.dist.php b/.php-cs-fixer.dist.php
index 2622f4406..ddf644ab6 100644
--- a/.php-cs-fixer.dist.php
+++ b/.php-cs-fixer.dist.php
@@ -1,7 +1,9 @@
 <?php
 
 use PhpCsFixer\Config;
+use PhpCsFixer\Config\RuleCustomisationPolicyInterface;
 use PhpCsFixer\Finder;
+use PhpCsFixer\Runner\Parallel\ParallelConfigFactory;
 
 return (new Config())
     ->setRules([
@@ -18,6 +20,46 @@ return (new Config())
         'phpdoc_types_order' => ['null_adjustment' => 'always_last', 'sort_algorithm' => 'none'],
         'no_superfluous_phpdoc_tags' => ['allow_mixed' => true, 'allow_unused_params' => true],
     ])
+    ->setRuleCustomisationPolicy(new class implements RuleCustomisationPolicyInterface {
+        public function getPolicyVersionForCache(): string
+        {
+            return hash_file('xxh128', __FILE__);
+        }
+
+        public function getRuleCustomisers(): array
+        {
+            return [
+                'void_return' => static function (\SplFileInfo $file) {
+                    $pathname = str_replace('\\', '/', $file->getPathname());
+
+                    // These files intentionally omit void return types on extension points to preserve Twig 3.x subclass compatibility.
+                    foreach ([
+                        'extra/twig-extra-bundle/DependencyInjection/Compiler/MissingExtensionSuggestorPass.php',
+                        'extra/twig-extra-bundle/DependencyInjection/TwigExtraExtension.php',
+                        'extra/twig-extra-bundle/TwigExtraBundle.php',
+                        'src/Environment.php',
+                        'src/Extension/ProfilerExtension.php',
+                        'src/Node/CheckSecurityCallNode.php',
+                        'src/Node/Expression/CallExpression.php',
+                        'src/Node/Expression/FunctionExpression.php',
+                        'src/Node/IncludeNode.php',
+                        'src/Node/Node.php',
+                        'src/Node/TypesNode.php',
+                        'src/Parser.php',
+                        'src/Test/IntegrationTestCase.php',
+                        'src/Test/NodeTestCase.php',
+                    ] as $excludedPathname) {
+                        if ($excludedPathname === $pathname || str_ends_with($pathname, '/'.$excludedPathname)) {
+                            return false;
+                        }
+                    }
+
+                    return true;
+                },
+            ];
+        }
+    })
     ->setRiskyAllowed(true)
+    ->setParallelConfig(ParallelConfigFactory::detect())
     ->setFinder((new Finder())->in(__DIR__))
 ;
diff --git a/extra/twig-extra-bundle/DependencyInjection/Compiler/MissingExtensionSuggestorPass.php b/extra/twig-extra-bundle/DependencyInjection/Compiler/MissingExtensionSuggestorPass.php
index 7833336bc..fdd65820b 100644
--- a/extra/twig-extra-bundle/DependencyInjection/Compiler/MissingExtensionSuggestorPass.php
+++ b/extra/twig-extra-bundle/DependencyInjection/Compiler/MissingExtensionSuggestorPass.php
@@ -34,7 +34,8 @@ if (!method_exists(ContainerBuilder::class, 'getAutoconfiguredAttributes')) {
 } else {
     class MissingExtensionSuggestorPass implements CompilerPassInterface
     {
-        public function process(ContainerBuilder $container): void
+        /** @return void */
+        public function process(ContainerBuilder $container)
         {
             if (!$container->getParameter('kernel.debug')) {
                 return;
diff --git a/extra/twig-extra-bundle/DependencyInjection/TwigExtraExtension.php b/extra/twig-extra-bundle/DependencyInjection/TwigExtraExtension.php
index 6de993717..b7f732f90 100644
--- a/extra/twig-extra-bundle/DependencyInjection/TwigExtraExtension.php
+++ b/extra/twig-extra-bundle/DependencyInjection/TwigExtraExtension.php
@@ -31,7 +31,8 @@ if (!method_exists(ContainerBuilder::class, 'getAutoconfiguredAttributes')) {
     /** @internal */
     trait TwigExtraExtensionTrait
     {
-        public function load(array $configs, ContainerBuilder $container): void
+        /** @return void */
+        public function load(array $configs, ContainerBuilder $container)
         {
             $this->doLoad($configs, $container);
         }
diff --git a/extra/twig-extra-bundle/TwigExtraBundle.php b/extra/twig-extra-bundle/TwigExtraBundle.php
index 5289e1feb..495785623 100644
--- a/extra/twig-extra-bundle/TwigExtraBundle.php
+++ b/extra/twig-extra-bundle/TwigExtraBundle.php
@@ -29,7 +29,8 @@ if (method_exists(KernelInterface::class, 'getShareDir')) {
 } else {
     class TwigExtraBundle extends Bundle
     {
-        public function build(ContainerBuilder $container): void
+        /** @return void */
+        public function build(ContainerBuilder $container)
         {
             parent::build($container);
 
diff --git a/src/Environment.php b/src/Environment.php
index b589a69f2..05098f0b7 100644
--- a/src/Environment.php
+++ b/src/Environment.php
@@ -154,8 +154,10 @@ class Environment
 
     /**
      * Enables debugging mode.
+     *
+     * @return void
      */
-    public function enableDebug(): void
+    public function enableDebug()
     {
         $this->debug = true;
         $this->updateOptionsHash();
@@ -163,8 +165,10 @@ class Environment
 
     /**
      * Disables debugging mode.
+     *
+     * @return void
      */
-    public function disableDebug(): void
+    public function disableDebug()
     {
         $this->debug = false;
         $this->updateOptionsHash();
@@ -182,16 +186,20 @@ class Environment
 
     /**
      * Enables the auto_reload option.
+     *
+     * @return void
      */
-    public function enableAutoReload(): void
+    public function enableAutoReload()
     {
         $this->autoReload = true;
     }
 
     /**
      * Disables the auto_reload option.
+     *
+     * @return void
      */
-    public function disableAutoReload(): void
+    public function disableAutoReload()
     {
         $this->autoReload = false;
     }
@@ -208,8 +216,10 @@ class Environment
 
     /**
      * Enables the strict_variables option.
+     *
+     * @return void
      */
-    public function enableStrictVariables(): void
+    public function enableStrictVariables()
     {
         $this->strictVariables = true;
         $this->updateOptionsHash();
@@ -217,8 +227,10 @@ class Environment
 
     /**
      * Disables the strict_variables option.
+     *
+     * @return void
      */
-    public function disableStrictVariables(): void
+    public function disableStrictVariables()
     {
         $this->strictVariables = false;
         $this->updateOptionsHash();
@@ -266,8 +278,10 @@ class Environment
      * @param CacheInterface|string|false $cache A Twig\Cache\CacheInterface implementation,
      *                                           an absolute path to the compiled templates,
      *                                           or false to disable cache
+     *
+     * @return void
      */
-    public function setCache($cache): void
+    public function setCache($cache)
     {
         if (\is_string($cache)) {
             $this->originalCache = $cache;
@@ -502,7 +516,10 @@ class Environment
         throw new LoaderError(\sprintf('Unable to find one of the following templates: "%s".', implode('", "', $names)));
     }
 
-    public function setLexer(Lexer $lexer): void
+    /**
+     * @return void
+     */
+    public function setLexer(Lexer $lexer)
     {
         $this->lexer = $lexer;
     }
@@ -519,7 +536,10 @@ class Environment
         return $this->lexer->tokenize($source);
     }
 
-    public function setParser(Parser $parser): void
+    /**
+     * @return void
+     */
+    public function setParser(Parser $parser)
     {
         $this->parser = $parser;
     }
@@ -538,7 +558,10 @@ class Environment
         return $this->parser->parse($stream);
     }
 
-    public function setCompiler(Compiler $compiler): void
+    /**
+     * @return void
+     */
+    public function setCompiler(Compiler $compiler)
     {
         $this->compiler = $compiler;
     }
@@ -572,7 +595,10 @@ class Environment
         }
     }
 
-    public function setLoader(LoaderInterface $loader): void
+    /**
+     * @return void
+     */
+    public function setLoader(LoaderInterface $loader)
     {
         $this->loader = $loader;
     }
@@ -582,7 +608,10 @@ class Environment
         return $this->loader;
     }
 
-    public function setCharset(string $charset): void
+    /**
+     * @return void
+     */
+    public function setCharset(string $charset)
     {
         if ('UTF8' === $charset = strtoupper($charset ?: '')) {
             // iconv on Windows requires "UTF-8" instead of "UTF8"
@@ -602,7 +631,10 @@ class Environment
         return $this->extensionSet->hasExtension($class);
     }
 
-    public function addRuntimeLoader(RuntimeLoaderInterface $loader): void
+    /**
+     * @return void
+     */
+    public function addRuntimeLoader(RuntimeLoaderInterface $loader)
     {
         $this->runtimeLoaders[] = $loader;
     }
@@ -649,7 +681,10 @@ class Environment
         throw new RuntimeError(\sprintf('Unable to load the "%s" runtime.', $class));
     }
 
-    public function addExtension(ExtensionInterface $extension): void
+    /**
+     * @return void
+     */
+    public function addExtension(ExtensionInterface $extension)
     {
         $this->extensionSet->addExtension($extension);
         $this->updateOptionsHash();
@@ -657,8 +692,10 @@ class Environment
 
     /**
      * @param ExtensionInterface[] $extensions An array of extensions
+     *
+     * @return void
      */
-    public function setExtensions(array $extensions): void
+    public function setExtensions(array $extensions)
     {
         $this->extensionSet->setExtensions($extensions);
         $this->updateOptionsHash();
@@ -672,7 +709,10 @@ class Environment
         return $this->extensionSet->getExtensions();
     }
 
-    public function addTokenParser(TokenParserInterface $parser): void
+    /**
+     * @return void
+     */
+    public function addTokenParser(TokenParserInterface $parser)
     {
         $this->extensionSet->addTokenParser($parser);
     }
@@ -703,7 +743,10 @@ class Environment
         $this->extensionSet->registerUndefinedTokenParserCallback($callable);
     }
 
-    public function addNodeVisitor(NodeVisitorInterface $visitor): void
+    /**
+     * @return void
+     */
+    public function addNodeVisitor(NodeVisitorInterface $visitor)
     {
         $this->extensionSet->addNodeVisitor($visitor);
     }
@@ -718,7 +761,10 @@ class Environment
         return $this->extensionSet->getNodeVisitors();
     }
 
-    public function addFilter(TwigFilter $filter): void
+    /**
+     * @return void
+     */
+    public function addFilter(TwigFilter $filter)
     {
         $this->extensionSet->addFilter($filter);
     }
@@ -755,7 +801,10 @@ class Environment
         return $this->extensionSet->getFilters();
     }
 
-    public function addTest(TwigTest $test): void
+    /**
+     * @return void
+     */
+    public function addTest(TwigTest $test)
     {
         $this->extensionSet->addTest($test);
     }
@@ -786,7 +835,10 @@ class Environment
         $this->extensionSet->registerUndefinedTestCallback($callable);
     }
 
-    public function addFunction(TwigFunction $function): void
+    /**
+     * @return void
+     */
+    public function addFunction(TwigFunction $function)
     {
         $this->extensionSet->addFunction($function);
     }
@@ -830,8 +882,10 @@ class Environment
      * but after, you can only update existing globals.
      *
      * @param mixed $value The global value
+     *
+     * @return void
      */
-    public function addGlobal(string $name, $value): void
+    public function addGlobal(string $name, $value)
     {
         if ($this->extensionSet->isInitialized() && !\array_key_exists($name, $this->getGlobals())) {
             throw new \LogicException(\sprintf('Unable to add global "%s" as the runtime or the extensions have already been initialized.', $name));
diff --git a/src/Extension/ProfilerExtension.php b/src/Extension/ProfilerExtension.php
index b3ad42cc8..43e4a449e 100644
--- a/src/Extension/ProfilerExtension.php
+++ b/src/Extension/ProfilerExtension.php
@@ -23,13 +23,19 @@ class ProfilerExtension extends AbstractExtension
         $this->actives[] = $profile;
     }
 
-    public function enter(Profile $profile): void
+    /**
+     * @return void
+     */
+    public function enter(Profile $profile)
     {
         $this->actives[0]->addProfile($profile);
         array_unshift($this->actives, $profile);
     }
 
-    public function leave(Profile $profile): void
+    /**
+     * @return void
+     */
+    public function leave(Profile $profile)
     {
         $profile->leave();
         array_shift($this->actives);
diff --git a/src/Node/CheckSecurityCallNode.php b/src/Node/CheckSecurityCallNode.php
index a32a14fd7..a248040b1 100644
--- a/src/Node/CheckSecurityCallNode.php
+++ b/src/Node/CheckSecurityCallNode.php
@@ -20,7 +20,10 @@ use Twig\Compiler;
 #[YieldReady]
 class CheckSecurityCallNode extends Node
 {
-    public function compile(Compiler $compiler): void
+    /**
+     * @return void
+     */
+    public function compile(Compiler $compiler)
     {
         $compiler
             ->write("\$this->sandbox = \$this->extensions[SandboxExtension::class]->getChecker();\n")
diff --git a/src/Node/Expression/CallExpression.php b/src/Node/Expression/CallExpression.php
index 6dda9c041..94036c1d3 100644
--- a/src/Node/Expression/CallExpression.php
+++ b/src/Node/Expression/CallExpression.php
@@ -26,7 +26,10 @@ abstract class CallExpression extends AbstractExpression
 {
     private $reflector;
 
-    protected function compileCallable(Compiler $compiler): void
+    /**
+     * @return void
+     */
+    protected function compileCallable(Compiler $compiler)
     {
         $twigCallable = $this->getTwigCallable();
         $callable = $twigCallable->getCallable();
diff --git a/src/Node/Expression/FunctionExpression.php b/src/Node/Expression/FunctionExpression.php
index 6fd555f4b..5983962dc 100644
--- a/src/Node/Expression/FunctionExpression.php
+++ b/src/Node/Expression/FunctionExpression.php
@@ -55,7 +55,10 @@ class FunctionExpression extends CallExpression implements SupportDefinedTestInt
         }
     }
 
-    public function compile(Compiler $compiler): void
+    /**
+     * @return void
+     */
+    public function compile(Compiler $compiler)
     {
         $name = $this->getAttribute('name');
         if ($this->hasAttribute('twig_callable')) {
diff --git a/src/Node/IncludeNode.php b/src/Node/IncludeNode.php
index 9d4fe664b..3adf415e1 100644
--- a/src/Node/IncludeNode.php
+++ b/src/Node/IncludeNode.php
@@ -79,7 +79,10 @@ class IncludeNode extends Node implements NodeOutputInterface, CoercesChildrenTo
         }
     }
 
-    protected function addGetTemplate(Compiler $compiler/* , string $template = '' */): void
+    /**
+     * @return void
+     */
+    protected function addGetTemplate(Compiler $compiler/* , string $template = '' */)
     {
         $compiler
             ->raw('$this->load(')
@@ -90,7 +93,10 @@ class IncludeNode extends Node implements NodeOutputInterface, CoercesChildrenTo
         ;
     }
 
-    protected function addTemplateArguments(Compiler $compiler): void
+    /**
+     * @return void
+     */
+    protected function addTemplateArguments(Compiler $compiler)
     {
         if (!$this->hasNode('variables')) {
             $compiler->raw(false === $this->getAttribute('only') ? '$context' : '[]');
diff --git a/src/Node/Node.php b/src/Node/Node.php
index dd784d3a5..bfa4f030f 100644
--- a/src/Node/Node.php
+++ b/src/Node/Node.php
@@ -117,7 +117,10 @@ class Node implements \Countable, \IteratorAggregate
         }
     }
 
-    public function compile(Compiler $compiler): void
+    /**
+     * @return void
+     */
+    public function compile(Compiler $compiler)
     {
         foreach ($this->nodes as $node) {
             $compiler->subcompile($node);
diff --git a/src/Node/TypesNode.php b/src/Node/TypesNode.php
index 0724cd95a..4009701fd 100644
--- a/src/Node/TypesNode.php
+++ b/src/Node/TypesNode.php
@@ -35,7 +35,10 @@ class TypesNode extends Node
         parent::__construct($nodes, ['mapping' => $types], $lineno);
     }
 
-    public function compile(Compiler $compiler): void
+    /**
+     * @return void
+     */
+    public function compile(Compiler $compiler)
     {
         // Don't compile anything.
     }
diff --git a/src/Parser.php b/src/Parser.php
index 122876e44..2898b2689 100644
--- a/src/Parser.php
+++ b/src/Parser.php
@@ -335,7 +335,10 @@ class Parser
         return \count($this->traits) > 0;
     }
 
-    public function embedTemplate(ModuleNode $template): void
+    /**
+     * @return void
+     */
+    public function embedTemplate(ModuleNode $template)
     {
         $template->setIndex(++$this->lastEmbedIndex);
 
diff --git a/src/Test/IntegrationTestCase.php b/src/Test/IntegrationTestCase.php
index d76a22cc8..1941a7209 100644
--- a/src/Test/IntegrationTestCase.php
+++ b/src/Test/IntegrationTestCase.php
@@ -123,9 +123,11 @@ abstract class IntegrationTestCase extends TestCase
      * The annotation feeds PHPUnit < 10; the attribute feeds PHPUnit >= 10 and must point to a static provider, as PHPUnit >= 11 rejects non-static ones.
      *
      * @dataProvider getTests
+     *
+     * @return void
      */
     #[DataProvider('provideTests')]
-    public function testIntegration($file, $message, $condition, $templates, $exception, $outputs, $deprecation = ''): void
+    public function testIntegration($file, $message, $condition, $templates, $exception, $outputs, $deprecation = '')
     {
         $this->doIntegrationTest($file, $message, $condition, $templates, $exception, $outputs, $deprecation);
     }
@@ -134,9 +136,11 @@ abstract class IntegrationTestCase extends TestCase
      * @dataProvider getLegacyTests
      *
      * @group legacy
+     *
+     * @return void
      */
     #[DataProvider('provideLegacyTests'), Group('legacy')]
-    public function testLegacyIntegration($file, $message, $condition, $templates, $exception, $outputs, $deprecation = ''): void
+    public function testLegacyIntegration($file, $message, $condition, $templates, $exception, $outputs, $deprecation = '')
     {
         $this->doIntegrationTest($file, $message, $condition, $templates, $exception, $outputs, $deprecation);
     }
@@ -223,7 +227,10 @@ abstract class IntegrationTestCase extends TestCase
         return $this->getTests('testLegacyIntegration', true);
     }
 
-    protected function doIntegrationTest($file, $message, $condition, $templateSources, $exception, $outputs, $deprecation = ''): void
+    /**
+     * @return void
+     */
+    protected function doIntegrationTest($file, $message, $condition, $templateSources, $exception, $outputs, $deprecation = '')
     {
         if (!$outputs) {
             // dummy test added by assembleTests() when there is no (legacy) test to run
diff --git a/src/Test/NodeTestCase.php b/src/Test/NodeTestCase.php
index 5e60efcfb..3ce58b3bf 100644
--- a/src/Test/NodeTestCase.php
+++ b/src/Test/NodeTestCase.php
@@ -49,14 +49,19 @@ abstract class NodeTestCase extends TestCase
      *
      * @dataProvider getTests
      * @dataProvider provideTests
+     *
+     * @return void
      */
     #[DataProvider('provideTests')]
-    public function testCompile($node, $source, $environment = null, $isPattern = false): void
+    public function testCompile($node, $source, $environment = null, $isPattern = false)
     {
         $this->assertNodeCompilation($source, $node, $environment, $isPattern);
     }
 
-    public function assertNodeCompilation($source, Node $node, ?Environment $environment = null, $isPattern = false): void
+    /**
+     * @return void
+     */
+    public function assertNodeCompilation($source, Node $node, ?Environment $environment = null, $isPattern = false)
     {
         $compiler = $this->getCompiler($environment);
         $compiler->compile($node);