diff --git a/Tests/EventDispatcherTest.php b/Tests/EventDispatcherTest.php
index 59f6fcb..d6d0778 100644
--- a/Tests/EventDispatcherTest.php
+++ b/Tests/EventDispatcherTest.php
@@ -23,12 +23,8 @@ class EventDispatcherTest extends TestCase
     private const postFoo = 'post.foo';
     private const preBar = 'pre.bar';
 
-    /**
-     * @var EventDispatcher
-     */
-    private $dispatcher;
-
-    private $listener;
+    private EventDispatcher $dispatcher;
+    private TestEventListener $listener;
 
     protected function setUp(): void
     {
@@ -36,12 +32,6 @@ protected function setUp(): void
         $this->listener = new TestEventListener();
     }
 
-    protected function tearDown(): void
-    {
-        $this->dispatcher = null;
-        $this->listener = null;
-    }
-
     protected function createEventDispatcher()
     {
         return new EventDispatcher();
@@ -446,9 +436,9 @@ public function __invoke()
 
 class TestEventListener
 {
-    public $name;
-    public $preFooInvoked = false;
-    public $postFooInvoked = false;
+    public string $name;
+    public bool $preFooInvoked = false;
+    public bool $postFooInvoked = false;
 
     /* Listener methods */
 
@@ -473,9 +463,9 @@ public function __invoke()
 
 class TestWithDispatcher
 {
-    public $name;
-    public $dispatcher;
-    public $invoked = false;
+    public ?string $name = null;
+    public ?EventDispatcher $dispatcher = null;
+    public bool $invoked = false;
 
     public function foo($e, $name, $dispatcher)
     {
diff --git a/Tests/GenericEventTest.php b/Tests/GenericEventTest.php
index d13d536..15dac83 100644
--- a/Tests/GenericEventTest.php
+++ b/Tests/GenericEventTest.php
@@ -19,31 +19,15 @@
  */
 class GenericEventTest extends TestCase
 {
-    /**
-     * @var GenericEvent
-     */
-    private $event;
-
-    private $subject;
+    private GenericEvent $event;
+    private \stdClass $subject;
 
-    /**
-     * Prepares the environment before running a test.
-     */
     protected function setUp(): void
     {
         $this->subject = new \stdClass();
         $this->event = new GenericEvent($this->subject, ['name' => 'Event']);
     }
 
-    /**
-     * Cleans up the environment after running a test.
-     */
-    protected function tearDown(): void
-    {
-        $this->subject = null;
-        $this->event = null;
-    }
-
     public function testConstruct()
     {
         $this->assertEquals($this->event, new GenericEvent($this->subject, ['name' => 'Event']));
diff --git a/Tests/ImmutableEventDispatcherTest.php b/Tests/ImmutableEventDispatcherTest.php
index 35bab1a..af3ec95 100644
--- a/Tests/ImmutableEventDispatcherTest.php
+++ b/Tests/ImmutableEventDispatcherTest.php
@@ -23,15 +23,8 @@
  */
 class ImmutableEventDispatcherTest extends TestCase
 {
-    /**
-     * @var MockObject&EventDispatcherInterface
-     */
-    private $innerDispatcher;
-
-    /**
-     * @var ImmutableEventDispatcher
-     */
-    private $dispatcher;
+    private MockObject&EventDispatcherInterface $innerDispatcher;
+    private ImmutableEventDispatcher $dispatcher;
 
     protected function setUp(): void
     {