diff --git a/.gitignore b/.gitignore
index 5965d92..8886f97 100644
--- a/.gitignore
+++ b/.gitignore
@@ -2,3 +2,4 @@
 composer.lock
 .idea
 .php-cs-fixer.cache
+.phpunit.cache
diff --git a/composer.json b/composer.json
index 8628af7..1172189 100644
--- a/composer.json
+++ b/composer.json
@@ -8,10 +8,11 @@
     "php": "^8.2"
   },
   "require-dev": {
-    "phpunit/phpunit": "^8.0 || ^9.0",
+    "phpunit/phpunit": "^11.5",
     "broadway/coding-standard": "^1.2",
     "phpstan/phpstan": "^2.0",
-    "phpspec/prophecy": "^1.15"
+    "phpspec/prophecy": "^1.15",
+        "phpspec/prophecy-phpunit": "^2.2"
   },
   "authors": [
     {
diff --git a/phpunit.xml.dist b/phpunit.xml.dist
index c5804e5..f32fa41 100644
--- a/phpunit.xml.dist
+++ b/phpunit.xml.dist
@@ -1,28 +1,18 @@
 <?xml version="1.0" encoding="UTF-8"?>
-
-<phpunit backupGlobals="false"
-         backupStaticAttributes="false"
-         bootstrap="vendor/autoload.php"
-         colors="true"
-         convertErrorsToExceptions="true"
-         convertNoticesToExceptions="true"
-         convertWarningsToExceptions="true"
-         processIsolation="false"
-         stopOnFailure="false"
-        >
-    <testsuites>
-        <testsuite name="Test Suite">
-            <directory>./test/</directory>
-        </testsuite>
-    </testsuites>
-    <filter>
-        <whitelist>
-            <directory suffix=".php">./src/</directory>
-        </whitelist>
-    </filter>
-    <groups>
-        <exclude>
-            <group>functional</group>
-        </exclude>
-    </groups>
+<phpunit backupGlobals="false" bootstrap="vendor/autoload.php" colors="true" processIsolation="false" stopOnFailure="false" cacheDirectory=".phpunit.cache" backupStaticProperties="false">
+  <testsuites>
+    <testsuite name="Test Suite">
+      <directory>./test/</directory>
+    </testsuite>
+  </testsuites>
+  <groups>
+    <exclude>
+      <group>functional</group>
+    </exclude>
+  </groups>
+  <source>
+    <include>
+      <directory suffix=".php">./src/</directory>
+    </include>
+  </source>
 </phpunit>
diff --git a/test/EventSourcing/SnapshottingEventSourcingRepositoryTest.php b/test/EventSourcing/SnapshottingEventSourcingRepositoryTest.php
index b60e73a..0b40e6d 100644
--- a/test/EventSourcing/SnapshottingEventSourcingRepositoryTest.php
+++ b/test/EventSourcing/SnapshottingEventSourcingRepositoryTest.php
@@ -24,10 +24,14 @@
 use Broadway\Snapshotting\Snapshot\SnapshotRepository;
 use Broadway\Snapshotting\Snapshot\Snapshotter;
 use Broadway\Snapshotting\Snapshot\Trigger\EventCountTrigger;
+use PHPUnit\Framework\Attributes\Test;
 use Prophecy\Argument;
+use Prophecy\PhpUnit\ProphecyTrait;
 
 class SnapshottingEventSourcingRepositoryTest extends \PHPUnit\Framework\TestCase
 {
+    use ProphecyTrait;
+
     private $eventStore;
     private $eventSourcingRepository;
     private $snapshotRepository;
@@ -50,9 +54,7 @@ public function setUp(): void
         );
     }
 
-    /**
-     * @test
-     */
+    #[Test]
     public function it_reconstitutes_aggregate_when_no_snapshot_found()
     {
         $this->snapshotRepository
@@ -70,9 +72,7 @@ public function it_reconstitutes_aggregate_when_no_snapshot_found()
         $this->snapshottingEventSourcingRepository->load(42);
     }
 
-    /**
-     * @test
-     */
+    #[Test]
     public function it_queries_the_event_store_for_events_recorded_after_playhead_of_snapshot()
     {
         // create a snapshot of an aggregate root with 5 committed events
@@ -106,9 +106,7 @@ public function it_queries_the_event_store_for_events_recorded_after_playhead_of
         $this->assertEquals(6, $aggregateRoot->getPlayhead());
     }
 
-    /**
-     * @test
-     */
+    #[Test]
     public function it_does_not_take_a_snapshot_when_threshold_not_reached()
     {
         $aggregateRoot = $this->createAggregateRootWithEvents(99);
@@ -121,9 +119,7 @@ public function it_does_not_take_a_snapshot_when_threshold_not_reached()
         $this->snapshottingEventSourcingRepository->save($aggregateRoot);
     }
 
-    /**
-     * @test
-     */
+    #[Test]
     public function it_takes_a_snapshot_when_threshold_reached()
     {
         $aggregateRoot = $this->createAggregateRootWithEvents(100);
diff --git a/test/Snapshot/InMemorySnapshotRepositoryTest.php b/test/Snapshot/InMemorySnapshotRepositoryTest.php
index 54f9618..3ca9778 100644
--- a/test/Snapshot/InMemorySnapshotRepositoryTest.php
+++ b/test/Snapshot/InMemorySnapshotRepositoryTest.php
@@ -12,7 +12,7 @@
 
 namespace Broadway\Snapshotting\Snapshot;
 
-class InMemorySnapshotRepositoryTest extends SnapshotRepositoryTest
+class InMemorySnapshotRepositoryTest extends SnapshotRepositoryTestCase
 {
     /**
      * @return SnapshotRepository
diff --git a/test/Snapshot/SnapshotRepositoryTest.php b/test/Snapshot/SnapshotRepositoryTestCase.php
similarity index 93%
rename from test/Snapshot/SnapshotRepositoryTest.php
rename to test/Snapshot/SnapshotRepositoryTestCase.php
index 368c510..6e8fe43 100644
--- a/test/Snapshot/SnapshotRepositoryTest.php
+++ b/test/Snapshot/SnapshotRepositoryTestCase.php
@@ -13,33 +13,28 @@
 namespace Broadway\Snapshotting\Snapshot;
 
 use Broadway\EventSourcing\EventSourcedAggregateRoot;
+use PHPUnit\Framework\Attributes\Test;
 
-abstract class SnapshotRepositoryTest extends \PHPUnit\Framework\TestCase
+abstract class SnapshotRepositoryTestCase extends \PHPUnit\Framework\TestCase
 {
     /**
      * @var SnapshotRepository
      */
     protected $repository;
 
-    /**
-     * @test
-     */
+    #[Test]
     public function it_implements__snapshot_repository()
     {
         $this->assertInstanceOf(SnapshotRepository::class, $this->repository);
     }
 
-    /**
-     * @test
-     */
+    #[Test]
     public function it_returns_null_when_no_snapshot_available()
     {
         $this->assertNull($this->repository->load(42));
     }
 
-    /**
-     * @test
-     */
+    #[Test]
     public function it_returns_snapshot_when_available()
     {
         $aggregate = $this->createAggregateWithHistory(5);
@@ -51,9 +46,7 @@ public function it_returns_snapshot_when_available()
         );
     }
 
-    /**
-     * @test
-     */
+    #[Test]
     public function it_does_not_mutate_state_of__snapshot__aggregate_after_persisting()
     {
         $aggregate = $this->createAggregateWithHistory(5);
@@ -67,9 +60,7 @@ public function it_does_not_mutate_state_of__snapshot__aggregate_after_persistin
         $this->assertEquals(new Snapshot($this->createAggregateWithHistory(5)), $snapshot);
     }
 
-    /**
-     * @test
-     */
+    #[Test]
     public function it_does_not_mutate_state_of__snapshot__aggregate_after_loading()
     {
         $aggregate = $this->createAggregateWithHistory(5);
diff --git a/test/Snapshot/Snapshotter/CommandDispatchingSnapshotterTest.php b/test/Snapshot/Snapshotter/CommandDispatchingSnapshotterTest.php
index 6248205..c986d7f 100644
--- a/test/Snapshot/Snapshotter/CommandDispatchingSnapshotterTest.php
+++ b/test/Snapshot/Snapshotter/CommandDispatchingSnapshotterTest.php
@@ -15,9 +15,13 @@
 use Broadway\CommandHandling\CommandBus;
 use Broadway\EventSourcing\EventSourcedAggregateRoot;
 use Broadway\Snapshotting\Snapshot\Command\ScheduleSnapshot;
+use PHPUnit\Framework\Attributes\Test;
+use Prophecy\PhpUnit\ProphecyTrait;
 
 class CommandDispatchingSnapshotterTest extends \PHPUnit\Framework\TestCase
 {
+    use ProphecyTrait;
+
     /**
      * @var CommandBus
      */
@@ -28,9 +32,7 @@ class CommandDispatchingSnapshotterTest extends \PHPUnit\Framework\TestCase
      */
     private $snapshotter;
 
-    /**
-     * @test
-     */
+    #[Test]
     public function it_dispatches__schedule_snapshot_command()
     {
         $this->commandBus
diff --git a/test/Snapshot/Snapshotter/SynchronousSnapshotterTest.php b/test/Snapshot/Snapshotter/SynchronousSnapshotterTest.php
index 58d5a97..613da00 100644
--- a/test/Snapshot/Snapshotter/SynchronousSnapshotterTest.php
+++ b/test/Snapshot/Snapshotter/SynchronousSnapshotterTest.php
@@ -15,9 +15,13 @@
 use Broadway\EventSourcing\EventSourcedAggregateRoot;
 use Broadway\Snapshotting\Snapshot\Snapshot;
 use Broadway\Snapshotting\Snapshot\SnapshotRepository;
+use PHPUnit\Framework\Attributes\Test;
+use Prophecy\PhpUnit\ProphecyTrait;
 
 class SynchronousSnapshotterTest extends \PHPUnit\Framework\TestCase
 {
+    use ProphecyTrait;
+
     /**
      * @var SnapshotRepository
      */
@@ -28,9 +32,7 @@ class SynchronousSnapshotterTest extends \PHPUnit\Framework\TestCase
      */
     private $snapshotter;
 
-    /**
-     * @test
-     */
+    #[Test]
     public function it_persists_directly_to__snapshot_repository()
     {
         $aggregate = new MyAggregate();
diff --git a/test/Snapshot/Trigger/EventCountTriggerTest.php b/test/Snapshot/Trigger/EventCountTriggerTest.php
index 8309e0b..4f0c42e 100644
--- a/test/Snapshot/Trigger/EventCountTriggerTest.php
+++ b/test/Snapshot/Trigger/EventCountTriggerTest.php
@@ -14,12 +14,11 @@
 namespace Broadway\Snapshotting\Snapshot\Trigger;
 
 use Broadway\Snapshotting\EventSourcing\Testing\TestEventSourcedAggregateRoot;
+use PHPUnit\Framework\Attributes\Test;
 
 class EventCountTriggerTest extends \PHPUnit\Framework\TestCase
 {
-    /**
-     * @test
-     */
+    #[Test]
     public function it_should_snapshot_when_number_of_uncommitted_events_exceeds_given_event_count()
     {
         $trigger = new EventCountTrigger(1);