diff --git a/baseline.xml b/baseline.xml
index 2a1ccf71c..e107ec3e1 100644
--- a/baseline.xml
+++ b/baseline.xml
@@ -56,12 +56,16 @@
       <code><![CDATA[$projectionError->errorContext]]></code>
     </PossiblyNullPropertyFetch>
   </file>
-  <file src="src/Projection/Projectionist/DefaultProjectionist.php">
+  <file src="src/Projection/Projector/MetadataProjectorAccessor.php">
     <MixedMethodCall>
       <code><![CDATA[$method]]></code>
       <code><![CDATA[$method]]></code>
       <code><![CDATA[$method]]></code>
     </MixedMethodCall>
+    <MixedReturnTypeCoercion>
+      <code><![CDATA[$this->projector->$method(...)]]></code>
+      <code><![CDATA[Closure(Message):void]]></code>
+    </MixedReturnTypeCoercion>
   </file>
   <file src="src/Repository/DefaultRepository.php">
     <PropertyTypeCoercion>
diff --git a/src/Projection/Projectionist/DefaultProjectionist.php b/src/Projection/Projectionist/DefaultProjectionist.php
index 6c6652f3d..0f3e905c5 100644
--- a/src/Projection/Projectionist/DefaultProjectionist.php
+++ b/src/Projection/Projectionist/DefaultProjectionist.php
@@ -792,7 +792,6 @@ private function discoverNewProjections(): void
             new ProjectionCriteria(),
             function (array $projections): void {
                 foreach ($this->projectorRepository->all() as $projector) {
-
                     foreach ($projections as $projection) {
                         if ($projection->id() === $projector->id()) {
                             continue 2;
@@ -804,7 +803,7 @@ function (array $projections): void {
                             $projector->id(),
                             $projector->group(),
                             $projector->runMode(),
-                        )
+                        ),
                     );
 
                     $this->logger?->info(
diff --git a/src/Projection/Projector/MetadataProjectorAccessor.php b/src/Projection/Projector/MetadataProjectorAccessor.php
index a9bb0ac43..543c406fb 100644
--- a/src/Projection/Projector/MetadataProjectorAccessor.php
+++ b/src/Projection/Projector/MetadataProjectorAccessor.php
@@ -1,17 +1,22 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Patchlevel\EventSourcing\Projection\Projector;
 
 use Closure;
 use Patchlevel\EventSourcing\Attribute\Subscribe;
+use Patchlevel\EventSourcing\EventBus\Message;
 use Patchlevel\EventSourcing\Metadata\Projector\ProjectorMetadata;
 use Patchlevel\EventSourcing\Projection\Projection\RunMode;
 
+use function array_key_exists;
+use function array_map;
+use function array_merge;
+
 final class MetadataProjectorAccessor implements ProjectorAccessor
 {
-    /**
-     * @var array<class-string, iterable<Closure>>
-     */
+    /** @var array<class-string, list<Closure(Message):void>> */
     private array $subscribeCache = [];
 
     public function __construct(
@@ -60,9 +65,9 @@ public function teardownMethod(): Closure|null
     /**
      * @param class-string $eventClass
      *
-     * @return iterable<Closure>
+     * @return list<Closure(Message):void>
      */
-    public function subscribeMethods(string $eventClass): iterable
+    public function subscribeMethods(string $eventClass): array
     {
         if (array_key_exists($eventClass, $this->subscribeCache)) {
             return $this->subscribeCache[$eventClass];
@@ -74,10 +79,11 @@ public function subscribeMethods(string $eventClass): iterable
         );
 
         $this->subscribeCache[$eventClass] = array_map(
-            fn(string $method) => $this->projector->$method(...),
+            /** @return Closure(Message):void */
+            fn (string $method) => $this->projector->$method(...),
             $methods,
         );
 
         return $this->subscribeCache[$eventClass];
     }
-}
\ No newline at end of file
+}
diff --git a/src/Projection/Projector/MetadataProjectorAccessorRepository.php b/src/Projection/Projector/MetadataProjectorAccessorRepository.php
index 0734ec67d..81c4714a0 100644
--- a/src/Projection/Projector/MetadataProjectorAccessorRepository.php
+++ b/src/Projection/Projector/MetadataProjectorAccessorRepository.php
@@ -1,53 +1,51 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Patchlevel\EventSourcing\Projection\Projector;
 
 use Patchlevel\EventSourcing\Metadata\Projector\AttributeProjectorMetadataFactory;
 use Patchlevel\EventSourcing\Metadata\Projector\ProjectorMetadataFactory;
 
+use function array_values;
+
 final class MetadataProjectorAccessorRepository implements ProjectorAccessorRepository
 {
-    private bool $init = false;
-
-    /**
-     * @var array<string, ProjectorAccessor>
-     */
+    /** @var array<string, ProjectorAccessor> */
     private array $projectorsMap = [];
 
+    /** @param iterable<object> $projectors */
     public function __construct(
         private readonly iterable $projectors,
-        private readonly ProjectorMetadataFactory $metadataFactory = new AttributeProjectorMetadataFactory()
+        private readonly ProjectorMetadataFactory $metadataFactory = new AttributeProjectorMetadataFactory(),
     ) {
     }
 
-    /**
-     * @return iterable<ProjectorAccessor>
-     */
+    /** @return iterable<ProjectorAccessor> */
     public function all(): iterable
     {
-        if ($this->init === false) {
-            $this->init();
-        }
-
-        return array_values($this->projectorsMap);
+        return array_values($this->projectorAccessorMap());
     }
 
     public function get(string $id): ProjectorAccessor|null
     {
-        if ($this->init === false) {
-            $this->init();
-        }
+        $map = $this->projectorAccessorMap();
 
-        return $this->projectorsMap[$id] ?? null;
+        return $map[$id] ?? null;
     }
 
-    private function init(): void
+    /** @return array<string, ProjectorAccessor> */
+    private function projectorAccessorMap(): array
     {
-        $this->init = true;
+        if ($this->projectorsMap !== []) {
+            return $this->projectorsMap;
+        }
 
         foreach ($this->projectors as $projector) {
             $metadata = $this->metadataFactory->metadata($projector::class);
             $this->projectorsMap[$metadata->id] = new MetadataProjectorAccessor($projector, $metadata);
         }
+
+        return $this->projectorsMap;
     }
-}
\ No newline at end of file
+}
diff --git a/src/Projection/Projector/ProjectorAccessor.php b/src/Projection/Projector/ProjectorAccessor.php
index 481d86514..00e378da5 100644
--- a/src/Projection/Projector/ProjectorAccessor.php
+++ b/src/Projection/Projector/ProjectorAccessor.php
@@ -1,8 +1,11 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Patchlevel\EventSourcing\Projection\Projector;
 
 use Closure;
+use Patchlevel\EventSourcing\EventBus\Message;
 use Patchlevel\EventSourcing\Projection\Projection\RunMode;
 
 interface ProjectorAccessor
@@ -12,6 +15,7 @@ public function id(): string;
     public function group(): string;
 
     public function runMode(): RunMode;
+
     public function setupMethod(): Closure|null;
 
     public function teardownMethod(): Closure|null;
@@ -19,7 +23,7 @@ public function teardownMethod(): Closure|null;
     /**
      * @param class-string $eventClass
      *
-     * @return iterable<Closure>
+     * @return list<Closure(Message):void>
      */
-    public function subscribeMethods(string $eventClass): iterable;
-}
\ No newline at end of file
+    public function subscribeMethods(string $eventClass): array;
+}
diff --git a/src/Projection/Projector/ProjectorAccessorRepository.php b/src/Projection/Projector/ProjectorAccessorRepository.php
index 4a7ecc1bd..267a97e51 100644
--- a/src/Projection/Projector/ProjectorAccessorRepository.php
+++ b/src/Projection/Projector/ProjectorAccessorRepository.php
@@ -1,13 +1,13 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Patchlevel\EventSourcing\Projection\Projector;
 
 interface ProjectorAccessorRepository
 {
-    /**
-     * @return iterable<ProjectorAccessor>
-     */
+    /** @return iterable<ProjectorAccessor> */
     public function all(): iterable;
 
     public function get(string $id): ProjectorAccessor|null;
-}
\ No newline at end of file
+}
diff --git a/src/Projection/Projector/TraceableProjectorAccessor.php b/src/Projection/Projector/TraceableProjectorAccessor.php
index 925026d15..1ba70b22d 100644
--- a/src/Projection/Projector/TraceableProjectorAccessor.php
+++ b/src/Projection/Projector/TraceableProjectorAccessor.php
@@ -1,15 +1,23 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Patchlevel\EventSourcing\Projection\Projector;
 
 use Closure;
+use Patchlevel\EventSourcing\EventBus\Message;
 use Patchlevel\EventSourcing\Projection\Projection\RunMode;
+use Patchlevel\EventSourcing\Repository\MessageDecorator\Trace;
+use Patchlevel\EventSourcing\Repository\MessageDecorator\TraceStack;
+
+use function array_map;
 
+/** @experimental */
 final class TraceableProjectorAccessor implements ProjectorAccessor
 {
     public function __construct(
         private readonly ProjectorAccessor $parent,
-        private readonly Closure $wrapper
+        private readonly TraceStack $traceStack,
     ) {
     }
 
@@ -41,13 +49,31 @@ public function teardownMethod(): Closure|null
     /**
      * @param class-string $eventClass
      *
-     * @return iterable<Closure>
+     * @return list<Closure(Message):void>
      */
-    public function subscribeMethods(string $eventClass): iterable
+    public function subscribeMethods(string $eventClass): array
     {
         return array_map(
-            fn(Closure $closure) => ($this->wrapper)($this, $closure),
-            $this->parent->subscribeMethods($eventClass)
+            /**
+             * @param Closure(Message):void $closure
+             *
+             * @return Closure(Message):void
+             */
+            fn (Closure $closure) => function (Message $message) use ($closure): void {
+                $trace = new Trace(
+                    $this->id(),
+                    'event_sourcing/projector/' . $this->group(),
+                );
+
+                $this->traceStack->add($trace);
+
+                try {
+                    $closure($message);
+                } finally {
+                    $this->traceStack->remove($trace);
+                }
+            },
+            $this->parent->subscribeMethods($eventClass),
         );
     }
-}
\ No newline at end of file
+}
diff --git a/src/Projection/Projector/TraceableProjectorAccessorRepository.php b/src/Projection/Projector/TraceableProjectorAccessorRepository.php
index a0eec472c..cb5beb789 100644
--- a/src/Projection/Projector/TraceableProjectorAccessorRepository.php
+++ b/src/Projection/Projector/TraceableProjectorAccessorRepository.php
@@ -1,19 +1,17 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Patchlevel\EventSourcing\Projection\Projector;
 
-use Closure;
-use Patchlevel\EventSourcing\EventBus\Message;
-use Patchlevel\EventSourcing\Repository\MessageDecorator\Trace;
 use Patchlevel\EventSourcing\Repository\MessageDecorator\TraceStack;
 
+use function array_values;
+
+/** @experimental */
 final class TraceableProjectorAccessorRepository implements ProjectorAccessorRepository
 {
-    private bool $init = false;
-
-    /**
-     * @var array<string, TraceableProjectorAccessor>
-     */
+    /** @var array<string, TraceableProjectorAccessor> */
     private array $projectorsMap = [];
 
     public function __construct(
@@ -22,53 +20,33 @@ public function __construct(
     ) {
     }
 
-    /**
-     * @return iterable<ProjectorAccessor>
-     */
+    /** @return iterable<TraceableProjectorAccessor> */
     public function all(): iterable
     {
-        if ($this->init === false) {
-            $this->init();
-        }
-
-        return array_values($this->projectorsMap);
+        return array_values($this->projectorAccessorMap());
     }
 
-    public function get(string $id): ProjectorAccessor|null
+    public function get(string $id): TraceableProjectorAccessor|null
     {
-        if ($this->init === false) {
-            $this->init();
-        }
+        $map = $this->projectorAccessorMap();
 
-        return $this->projectorsMap[$id] ?? null;
+        return $map[$id] ?? null;
     }
 
-    private function init(): void
+    /** @return array<string, TraceableProjectorAccessor> */
+    private function projectorAccessorMap(): array
     {
-        $this->init = true;
+        if ($this->projectorsMap !== []) {
+            return $this->projectorsMap;
+        }
 
         foreach ($this->parent->all() as $projectorAccessor) {
             $this->projectorsMap[$projectorAccessor->id()] = new TraceableProjectorAccessor(
                 $projectorAccessor,
-                $this->wrapper(...)
+                $this->traceStack,
             );
         }
-    }
-
-    public function wrapper($projectorAccessor, Closure $closure): Closure
-    {
-        return function (Message $message) use ($projectorAccessor, $closure) {
-            $trace = new Trace(
-                $projectorAccessor->id(),
-                'event_sourcing:' . $projectorAccessor->group()
-            );
 
-            $this->traceStack->add($trace);
-            try {
-                return $closure($message);
-            } finally {
-                $this->traceStack->remove($trace);
-            }
-        };
+        return $this->projectorsMap;
     }
-}
\ No newline at end of file
+}
diff --git a/src/Repository/MessageDecorator/Trace.php b/src/Repository/MessageDecorator/Trace.php
index 9de767192..bcc2357b3 100644
--- a/src/Repository/MessageDecorator/Trace.php
+++ b/src/Repository/MessageDecorator/Trace.php
@@ -1,13 +1,15 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Patchlevel\EventSourcing\Repository\MessageDecorator;
 
+/** @experimental */
 final class Trace
 {
     public function __construct(
         public readonly string $name,
         public readonly string $category,
-    )
-    {
+    ) {
     }
-}
\ No newline at end of file
+}
diff --git a/src/Repository/MessageDecorator/TraceDecorator.php b/src/Repository/MessageDecorator/TraceDecorator.php
index eb325a350..5ca913eba 100644
--- a/src/Repository/MessageDecorator/TraceDecorator.php
+++ b/src/Repository/MessageDecorator/TraceDecorator.php
@@ -1,10 +1,15 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Patchlevel\EventSourcing\Repository\MessageDecorator;
 
 use Patchlevel\EventSourcing\EventBus\Message;
 
-class TraceDecorator implements MessageDecorator
+use function array_map;
+
+/** @experimental */
+final class TraceDecorator implements MessageDecorator
 {
     public function __construct(
         private readonly TraceStack $traceStack,
@@ -19,12 +24,14 @@ public function __invoke(Message $message): Message
             return $message;
         }
 
-        return $message->withHeader('trace', array_map(
-            fn (Trace $trace) => [
-                'id' => $trace->name,
-                'type' => $trace->category,
-            ],
-            $traces
+        return $message->withHeader(new TraceHeader(
+            array_map(
+                static fn (Trace $trace) => [
+                    'name' => $trace->name,
+                    'category' => $trace->category,
+                ],
+                $traces,
+            ),
         ));
     }
-}
\ No newline at end of file
+}
diff --git a/src/Repository/MessageDecorator/TraceHeader.php b/src/Repository/MessageDecorator/TraceHeader.php
new file mode 100644
index 000000000..c7c10d231
--- /dev/null
+++ b/src/Repository/MessageDecorator/TraceHeader.php
@@ -0,0 +1,18 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Patchlevel\EventSourcing\Repository\MessageDecorator;
+
+use Patchlevel\EventSourcing\Attribute\Header;
+
+/** @experimental */
+#[Header('trace')]
+final class TraceHeader
+{
+    /** @param list<array{name: string, category: string}> $traces */
+    public function __construct(
+        public readonly array $traces,
+    ) {
+    }
+}
diff --git a/src/Repository/MessageDecorator/TraceStack.php b/src/Repository/MessageDecorator/TraceStack.php
index 1fd0400d5..24b71b9e3 100644
--- a/src/Repository/MessageDecorator/TraceStack.php
+++ b/src/Repository/MessageDecorator/TraceStack.php
@@ -1,21 +1,23 @@
 <?php
 
+declare(strict_types=1);
+
 namespace Patchlevel\EventSourcing\Repository\MessageDecorator;
+
+use function array_values;
+
+/** @experimental */
 final class TraceStack
 {
-    /**
-     * @var array<string, Trace>
-     */
+    /** @var array<string, Trace> */
     private array $traces = [];
 
     public function add(Trace $trace): void
     {
-        $this->traces[$trace->name] = $trace;
+        $this->traces[self::key($trace)] = $trace;
     }
 
-    /**
-     * @return iterable<Trace>
-     */
+    /** @return list<Trace> */
     public function get(): array
     {
         return array_values($this->traces);
@@ -23,11 +25,11 @@ public function get(): array
 
     public function remove(Trace $trace): void
     {
-        unset($this->traces[$trace->name]);
+        unset($this->traces[self::key($trace)]);
     }
 
     private static function key(Trace $trace): string
     {
         return $trace->category . '#' . $trace->name;
     }
-}
\ No newline at end of file
+}
diff --git a/tests/Integration/Projectionist/Aggregate/Profile.php b/tests/Integration/Projectionist/Aggregate/Profile.php
index 7c5599d62..64a4378a5 100644
--- a/tests/Integration/Projectionist/Aggregate/Profile.php
+++ b/tests/Integration/Projectionist/Aggregate/Profile.php
@@ -11,7 +11,6 @@
 use Patchlevel\EventSourcing\Serializer\Normalizer\IdNormalizer;
 use Patchlevel\EventSourcing\Tests\Integration\Projectionist\Events\NameChanged;
 use Patchlevel\EventSourcing\Tests\Integration\Projectionist\Events\ProfileCreated;
-use Patchlevel\EventSourcing\Tests\Integration\Projectionist\Events\Reborned;
 use Patchlevel\EventSourcing\Tests\Integration\Projectionist\ProfileId;
 
 #[Aggregate('profile')]
@@ -35,11 +34,6 @@ public function changeName(string $name): void
         $this->recordThat(new NameChanged($name));
     }
 
-    public function reborn(string $name): void
-    {
-        $this->recordThat(new Reborned($name));
-    }
-
     #[Apply]
     protected function applyProfileCreated(ProfileCreated $event): void
     {
@@ -53,12 +47,6 @@ protected function applyNameChanged(NameChanged $event): void
         $this->name = $event->name;
     }
 
-    #[Apply]
-    protected function applyReborned(Reborned $event): void
-    {
-        $this->name = $event->name;
-    }
-
     public function name(): string
     {
         return $this->name;
diff --git a/tests/Integration/Projectionist/Events/Reborned.php b/tests/Integration/Projectionist/Events/Reborned.php
deleted file mode 100644
index 2bbcb6acd..000000000
--- a/tests/Integration/Projectionist/Events/Reborned.php
+++ /dev/null
@@ -1,16 +0,0 @@
-<?php
-
-declare(strict_types=1);
-
-namespace Patchlevel\EventSourcing\Tests\Integration\Projectionist\Events;
-
-use Patchlevel\EventSourcing\Attribute\Event;
-
-#[Event('profile.reborned')]
-final class Reborned
-{
-    public function __construct(
-        public string $name,
-    ) {
-    }
-}
diff --git a/tests/Integration/Projectionist/Projection/ProfileProcessor.php b/tests/Integration/Projectionist/Projection/ProfileProcessor.php
index d4628cadd..7982cdcff 100644
--- a/tests/Integration/Projectionist/Projection/ProfileProcessor.php
+++ b/tests/Integration/Projectionist/Projection/ProfileProcessor.php
@@ -9,13 +9,11 @@
 use Patchlevel\EventSourcing\EventBus\Message;
 use Patchlevel\EventSourcing\Repository\RepositoryManager;
 use Patchlevel\EventSourcing\Tests\Integration\Projectionist\Aggregate\Profile;
-use Patchlevel\EventSourcing\Tests\Integration\Projectionist\Events\NameChanged;
 use Patchlevel\EventSourcing\Tests\Integration\Projectionist\Events\ProfileCreated;
 
-use Patchlevel\EventSourcing\Tests\Integration\Projectionist\ProfileId;
 use function assert;
 
-#[Projector('profile_change_name')]
+#[Projector('profile')]
 final class ProfileProcessor
 {
     public function __construct(
@@ -38,18 +36,4 @@ public function handleProfileCreated(Message $message): void
 
         $repository->save($profile);
     }
-
-    #[Subscribe(NameChanged::class)]
-    public function handleNameChanged(Message $message)
-    {
-        $id = ProfileId::fromString($message->aggregateId());
-
-        $repository = $this->repositoryManager->get(Profile::class);
-
-        $profile = $repository->load($id);
-
-        $profile->reborn('neo');
-
-        $repository->save($profile);
-    }
 }
diff --git a/tests/Integration/Projectionist/ProjectionistTest.php b/tests/Integration/Projectionist/ProjectionistTest.php
index 840cf35e6..0b5ca0c50 100644
--- a/tests/Integration/Projectionist/ProjectionistTest.php
+++ b/tests/Integration/Projectionist/ProjectionistTest.php
@@ -8,6 +8,7 @@
 use Doctrine\DBAL\Connection;
 use Patchlevel\EventSourcing\Clock\FrozenClock;
 use Patchlevel\EventSourcing\EventBus\DefaultEventBus;
+use Patchlevel\EventSourcing\EventBus\Message;
 use Patchlevel\EventSourcing\EventBus\Serializer\DefaultHeadersSerializer;
 use Patchlevel\EventSourcing\Metadata\AggregateRoot\AggregateRootRegistry;
 use Patchlevel\EventSourcing\Projection\Projection\Projection;
@@ -20,19 +21,22 @@
 use Patchlevel\EventSourcing\Projection\Projector\TraceableProjectorAccessorRepository;
 use Patchlevel\EventSourcing\Projection\RetryStrategy\ClockBasedRetryStrategy;
 use Patchlevel\EventSourcing\Repository\DefaultRepositoryManager;
-use Patchlevel\EventSourcing\Schema\ChainDoctrineSchemaConfigurator;
 use Patchlevel\EventSourcing\Repository\MessageDecorator\TraceDecorator;
+use Patchlevel\EventSourcing\Repository\MessageDecorator\TraceHeader;
 use Patchlevel\EventSourcing\Repository\MessageDecorator\TraceStack;
+use Patchlevel\EventSourcing\Schema\ChainDoctrineSchemaConfigurator;
 use Patchlevel\EventSourcing\Schema\DoctrineSchemaDirector;
 use Patchlevel\EventSourcing\Serializer\DefaultEventSerializer;
 use Patchlevel\EventSourcing\Store\DoctrineDbalStore;
 use Patchlevel\EventSourcing\Tests\DbalManager;
 use Patchlevel\EventSourcing\Tests\Integration\Projectionist\Aggregate\Profile;
-use Patchlevel\EventSourcing\Tests\Integration\Projectionist\Projection\ProfileProcessor;
 use Patchlevel\EventSourcing\Tests\Integration\Projectionist\Projection\ErrorProducerProjector;
+use Patchlevel\EventSourcing\Tests\Integration\Projectionist\Projection\ProfileProcessor;
 use Patchlevel\EventSourcing\Tests\Integration\Projectionist\Projection\ProfileProjector;
 use PHPUnit\Framework\TestCase;
 
+use function iterator_to_array;
+
 /** @coversNothing */
 final class ProjectionistTest extends TestCase
 {
@@ -133,8 +137,10 @@ public function testHappyPath(): void
             $projectionist->projections(),
         );
 
-        $result = $this->projectionConnection->fetchAssociative('SELECT * FROM projection_profile_1 WHERE id = ?',
-            ['1']);
+        $result = $this->projectionConnection->fetchAssociative(
+            'SELECT * FROM projection_profile_1 WHERE id = ?',
+            ['1'],
+        );
 
         self::assertIsArray($result);
         self::assertArrayHasKey('id', $result);
@@ -295,12 +301,15 @@ public function testErrorHandling(): void
         self::assertEquals(0, $projection->retryAttempt());
     }
 
-
     public function testProcessor(): void
     {
         $store = new DoctrineDbalStore(
             $this->connection,
             DefaultEventSerializer::createFromPaths([__DIR__ . '/Events']),
+            DefaultHeadersSerializer::createFromPaths([
+                __DIR__ . '/../../../src',
+                __DIR__,
+            ]),
             'eventstore',
         );
 
@@ -318,14 +327,12 @@ public function testProcessor(): void
             $store,
             DefaultEventBus::create(),
             null,
-            new TraceDecorator($traceStack)
+            new TraceDecorator($traceStack),
         );
 
         $projectorAccessorRepository = new TraceableProjectorAccessorRepository(
-            new MetadataProjectorAccessorRepository([
-                new ProfileProcessor($manager)
-            ]),
-            $traceStack
+            new MetadataProjectorAccessorRepository([new ProfileProcessor($manager)]),
+            $traceStack,
         );
 
         $repository = $manager->get(Profile::class);
@@ -347,7 +354,7 @@ public function testProcessor(): void
         );
 
         self::assertEquals(
-            [new Projection('profile_change_name', lastSavedAt: new DateTimeImmutable('2021-01-01T00:00:00'))],
+            [new Projection('profile', lastSavedAt: new DateTimeImmutable('2021-01-01T00:00:00'))],
             $projectionist->projections(),
         );
 
@@ -356,7 +363,7 @@ public function testProcessor(): void
         self::assertEquals(
             [
                 new Projection(
-                    'profile_change_name',
+                    'profile',
                     Projection::DEFAULT_GROUP,
                     RunMode::FromBeginning,
                     ProjectionStatus::Active,
@@ -371,23 +378,32 @@ public function testProcessor(): void
 
         $projectionist->run();
 
-        self::assertEquals(
-            [
-                new Projection(
-                    'profile_change_name',
-                    Projection::DEFAULT_GROUP,
-                    RunMode::FromBeginning,
-                    ProjectionStatus::Active,
-                    3,
-                    lastSavedAt: new DateTimeImmutable('2021-01-01T00:00:00'),
-                ),
-            ],
-            $projectionist->projections(),
-        );
+        $projections = $projectionist->projections();
+
+        self::assertCount(1, $projections);
+        self::assertArrayHasKey(0, $projections);
 
-        $events = $store->load();
+        $projection = $projections[0];
 
-        dd(iterator_to_array($events));
+        self::assertEquals('profile', $projection->id());
+
+        self::assertEquals(ProjectionStatus::Active, $projection->status());
+
+        /** @var list<Message> $messages */
+        $messages = iterator_to_array($store->load());
+
+        self::assertCount(2, $messages);
+        self::assertArrayHasKey(1, $messages);
+
+        self::assertEquals(
+            new TraceHeader([
+                [
+                    'name' => 'profile',
+                    'category' => 'event_sourcing/projector/default',
+                ],
+            ]),
+            $messages[1]->header(TraceHeader::class),
+        );
     }
 
     /** @param list<Projection> $projections */
diff --git a/tests/Unit/Projection/Projectionist/DefaultProjectionistTest.php b/tests/Unit/Projection/Projectionist/DefaultProjectionistTest.php
index 335065027..b87f83e0b 100644
--- a/tests/Unit/Projection/Projectionist/DefaultProjectionistTest.php
+++ b/tests/Unit/Projection/Projectionist/DefaultProjectionistTest.php
@@ -21,6 +21,7 @@
 use Patchlevel\EventSourcing\Projection\Projection\ThrowableToErrorContextTransformer;
 use Patchlevel\EventSourcing\Projection\Projectionist\DefaultProjectionist;
 use Patchlevel\EventSourcing\Projection\Projectionist\ProjectionistCriteria;
+use Patchlevel\EventSourcing\Projection\Projector\MetadataProjectorAccessorRepository;
 use Patchlevel\EventSourcing\Projection\RetryStrategy\RetryStrategy;
 use Patchlevel\EventSourcing\Store\ArrayStream;
 use Patchlevel\EventSourcing\Store\Criteria;
@@ -49,7 +50,7 @@ public function testNothingToBoot(): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $store,
-            [],
+            new MetadataProjectorAccessorRepository([]),
         );
 
         $projectionist->boot();
@@ -73,7 +74,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->boot();
@@ -122,7 +123,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->boot();
@@ -182,7 +183,7 @@ public function handle(Message $message): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->boot();
@@ -254,7 +255,7 @@ public function handle(Message $message): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->boot(new ProjectionistCriteria(), 1);
@@ -338,7 +339,7 @@ public function handle(Message $message): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector1, $projector2],
+            new MetadataProjectorAccessorRepository([$projector1, $projector2]),
         );
 
         $projectionist->boot();
@@ -405,7 +406,7 @@ public function create(): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->boot();
@@ -462,7 +463,7 @@ public function handle(Message $message): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->boot();
@@ -518,7 +519,7 @@ public function handle(Message $message): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->boot();
@@ -567,7 +568,7 @@ public function handle(Message $message): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->boot();
@@ -616,7 +617,7 @@ public function handle(Message $message): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->boot();
@@ -654,7 +655,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->run();
@@ -700,7 +701,7 @@ public function handle(Message $message): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->run();
@@ -753,7 +754,7 @@ public function handle(Message $message): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->run(new ProjectionistCriteria(), 1);
@@ -821,7 +822,7 @@ public function handle(Message $message): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector1, $projector2],
+            new MetadataProjectorAccessorRepository([$projector1, $projector2]),
         );
 
         $projectionist->run();
@@ -881,7 +882,7 @@ public function handle(Message $message): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->run();
@@ -924,7 +925,7 @@ public function testRunningMarkOutdated(): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [],
+            new MetadataProjectorAccessorRepository([]),
         );
 
         $projectionist->run();
@@ -959,7 +960,7 @@ public function testRunningWithoutActiveProjectors(): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [],
+            new MetadataProjectorAccessorRepository([]),
         );
 
         $projectionist->run();
@@ -1000,7 +1001,7 @@ public function handle(Message $message): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->run();
@@ -1031,7 +1032,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->teardown();
@@ -1067,7 +1068,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->teardown();
@@ -1105,7 +1106,7 @@ public function drop(): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->teardown();
@@ -1144,7 +1145,7 @@ public function drop(): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->teardown();
@@ -1171,7 +1172,7 @@ public function testTeardownWithoutProjector(): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [],
+            new MetadataProjectorAccessorRepository([]),
         );
 
         $projectionist->teardown();
@@ -1193,7 +1194,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->remove();
@@ -1235,7 +1236,7 @@ public function drop(): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->remove();
@@ -1265,7 +1266,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->remove();
@@ -1301,7 +1302,7 @@ public function drop(): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->remove();
@@ -1327,7 +1328,7 @@ public function testRemoveWithoutProjector(): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [],
+            new MetadataProjectorAccessorRepository([]),
         );
 
         $projectionist->remove();
@@ -1349,7 +1350,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->reactivate();
@@ -1387,7 +1388,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->reactivate();
@@ -1424,7 +1425,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->reactivate();
@@ -1460,7 +1461,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->reactivate();
@@ -1496,7 +1497,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->reactivate();
@@ -1524,7 +1525,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->pause();
@@ -1560,7 +1561,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->pause();
@@ -1596,7 +1597,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->pause();
@@ -1634,7 +1635,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->pause();
@@ -1664,7 +1665,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projections = $projectionist->projections();
@@ -1722,7 +1723,7 @@ public function subscribe(): void
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
             $retryStrategy->reveal(),
         );
 
@@ -1774,7 +1775,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore,
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
             $retryStrategy->reveal(),
         );
 
@@ -1809,7 +1810,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore->reveal(),
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionistCriteria = new ProjectionistCriteria(
@@ -1849,7 +1850,7 @@ class {
         $projectionist = new DefaultProjectionist(
             $streamableStore->reveal(),
             $projectionStore->reveal(),
-            [$projector],
+            new MetadataProjectorAccessorRepository([$projector]),
         );
 
         $projectionist->{$method}();