diff --git a/Debug/TraceableEventDispatcher.php b/Debug/TraceableEventDispatcher.php
index f1b9823..1b9ae64 100644
--- a/Debug/TraceableEventDispatcher.php
+++ b/Debug/TraceableEventDispatcher.php
@@ -43,7 +43,7 @@ class TraceableEventDispatcher implements EventDispatcherInterface, ResetInterfa
     private ?RequestStack $requestStack;
     private string $currentRequestHash = '';
 
-    public function __construct(EventDispatcherInterface $dispatcher, Stopwatch $stopwatch, LoggerInterface $logger = null, RequestStack $requestStack = null)
+    public function __construct(EventDispatcherInterface $dispatcher, Stopwatch $stopwatch, ?LoggerInterface $logger = null, ?RequestStack $requestStack = null)
     {
         $this->dispatcher = $dispatcher;
         $this->stopwatch = $stopwatch;
@@ -93,7 +93,7 @@ public function removeSubscriber(EventSubscriberInterface $subscriber)
         $this->dispatcher->removeSubscriber($subscriber);
     }
 
-    public function getListeners(string $eventName = null): array
+    public function getListeners(?string $eventName = null): array
     {
         return $this->dispatcher->getListeners($eventName);
     }
@@ -113,12 +113,12 @@ public function getListenerPriority(string $eventName, callable|array $listener)
         return $this->dispatcher->getListenerPriority($eventName, $listener);
     }
 
-    public function hasListeners(string $eventName = null): bool
+    public function hasListeners(?string $eventName = null): bool
     {
         return $this->dispatcher->hasListeners($eventName);
     }
 
-    public function dispatch(object $event, string $eventName = null): object
+    public function dispatch(object $event, ?string $eventName = null): object
     {
         $eventName ??= $event::class;
 
@@ -153,7 +153,7 @@ public function dispatch(object $event, string $eventName = null): object
         return $event;
     }
 
-    public function getCalledListeners(Request $request = null): array
+    public function getCalledListeners(?Request $request = null): array
     {
         if (null === $this->callStack) {
             return [];
@@ -171,7 +171,7 @@ public function getCalledListeners(Request $request = null): array
         return $called;
     }
 
-    public function getNotCalledListeners(Request $request = null): array
+    public function getNotCalledListeners(?Request $request = null): array
     {
         try {
             $allListeners = $this->dispatcher instanceof EventDispatcher ? $this->getListenersWithPriority() : $this->getListenersWithoutPriority();
@@ -213,7 +213,7 @@ public function getNotCalledListeners(Request $request = null): array
         return $notCalled;
     }
 
-    public function getOrphanedEvents(Request $request = null): array
+    public function getOrphanedEvents(?Request $request = null): array
     {
         if ($request) {
             return $this->orphanedEvents[spl_object_hash($request)] ?? [];
diff --git a/Debug/WrappedListener.php b/Debug/WrappedListener.php
index 6e0de1d..4dba883 100644
--- a/Debug/WrappedListener.php
+++ b/Debug/WrappedListener.php
@@ -34,7 +34,7 @@ final class WrappedListener
     private ?int $priority = null;
     private static bool $hasClassStub;
 
-    public function __construct(callable|array $listener, ?string $name, Stopwatch $stopwatch, EventDispatcherInterface $dispatcher = null, int $priority = null)
+    public function __construct(callable|array $listener, ?string $name, Stopwatch $stopwatch, ?EventDispatcherInterface $dispatcher = null, ?int $priority = null)
     {
         $this->listener = $listener;
         $this->optimizedListener = $listener instanceof \Closure ? $listener : (\is_callable($listener) ? $listener(...) : null);
diff --git a/EventDispatcher.php b/EventDispatcher.php
index 327803a..6052989 100644
--- a/EventDispatcher.php
+++ b/EventDispatcher.php
@@ -42,7 +42,7 @@ public function __construct()
         }
     }
 
-    public function dispatch(object $event, string $eventName = null): object
+    public function dispatch(object $event, ?string $eventName = null): object
     {
         $eventName ??= $event::class;
 
@@ -59,7 +59,7 @@ public function dispatch(object $event, string $eventName = null): object
         return $event;
     }
 
-    public function getListeners(string $eventName = null): array
+    public function getListeners(?string $eventName = null): array
     {
         if (null !== $eventName) {
             if (empty($this->listeners[$eventName])) {
@@ -108,7 +108,7 @@ public function getListenerPriority(string $eventName, callable|array $listener)
         return null;
     }
 
-    public function hasListeners(string $eventName = null): bool
+    public function hasListeners(?string $eventName = null): bool
     {
         if (null !== $eventName) {
             return !empty($this->listeners[$eventName]);
diff --git a/EventDispatcherInterface.php b/EventDispatcherInterface.php
index 3cd94c9..e95a7b1 100644
--- a/EventDispatcherInterface.php
+++ b/EventDispatcherInterface.php
@@ -59,7 +59,7 @@ public function removeSubscriber(EventSubscriberInterface $subscriber);
      *
      * @return array<callable[]|callable>
      */
-    public function getListeners(string $eventName = null): array;
+    public function getListeners(?string $eventName = null): array;
 
     /**
      * Gets the listener priority for a specific event.
@@ -71,5 +71,5 @@ public function getListenerPriority(string $eventName, callable $listener): ?int
     /**
      * Checks whether an event has any registered listeners.
      */
-    public function hasListeners(string $eventName = null): bool;
+    public function hasListeners(?string $eventName = null): bool;
 }
diff --git a/ImmutableEventDispatcher.php b/ImmutableEventDispatcher.php
index d385d3f..301a805 100644
--- a/ImmutableEventDispatcher.php
+++ b/ImmutableEventDispatcher.php
@@ -25,7 +25,7 @@ public function __construct(EventDispatcherInterface $dispatcher)
         $this->dispatcher = $dispatcher;
     }
 
-    public function dispatch(object $event, string $eventName = null): object
+    public function dispatch(object $event, ?string $eventName = null): object
     {
         return $this->dispatcher->dispatch($event, $eventName);
     }
@@ -62,7 +62,7 @@ public function removeSubscriber(EventSubscriberInterface $subscriber)
         throw new \BadMethodCallException('Unmodifiable event dispatchers must not be modified.');
     }
 
-    public function getListeners(string $eventName = null): array
+    public function getListeners(?string $eventName = null): array
     {
         return $this->dispatcher->getListeners($eventName);
     }
@@ -72,7 +72,7 @@ public function getListenerPriority(string $eventName, callable|array $listener)
         return $this->dispatcher->getListenerPriority($eventName, $listener);
     }
 
-    public function hasListeners(string $eventName = null): bool
+    public function hasListeners(?string $eventName = null): bool
     {
         return $this->dispatcher->hasListeners($eventName);
     }