diff --git a/src/Internal/Marshaller/Type/ArrayType.php b/src/Internal/Marshaller/Type/ArrayType.php
index bbdb4b22..5855485a 100644
--- a/src/Internal/Marshaller/Type/ArrayType.php
+++ b/src/Internal/Marshaller/Type/ArrayType.php
@@ -58,6 +58,10 @@ public static function match(\ReflectionNamedType $type): bool
      */
     public function parse($value, $current)
     {
+        if ($value === null) {
+            return null;
+        }
+
         if (!\is_array($value)) {
             throw new \InvalidArgumentException(\sprintf(self::ERROR_INVALID_TYPE, \get_debug_type($value)));
         }
diff --git a/tests/Fixtures/src/Activity/SimpleActivity.php b/tests/Fixtures/src/Activity/SimpleActivity.php
index 8b327683..729cada2 100644
--- a/tests/Fixtures/src/Activity/SimpleActivity.php
+++ b/tests/Fixtures/src/Activity/SimpleActivity.php
@@ -18,8 +18,8 @@
 use Temporal\DataConverter\Bytes;
 use Temporal\Tests\DTO\Message;
 use Temporal\Tests\DTO\User;
-use Temporal\Tests\Unit\DTO\Enum\SimpleEnum;
-use Temporal\Tests\Unit\DTO\Enum\ScalarEnum;
+use Temporal\Tests\Unit\DTO\Type\EnumType\ScalarEnum;
+use Temporal\Tests\Unit\DTO\Type\EnumType\SimpleEnum;
 
 #[ActivityInterface(prefix: "SimpleActivity.")]
 class SimpleActivity
diff --git a/tests/Fixtures/src/Workflow/ScalarEnumWorkflow.php b/tests/Fixtures/src/Workflow/ScalarEnumWorkflow.php
index 9e4100ff..98404bb0 100644
--- a/tests/Fixtures/src/Workflow/ScalarEnumWorkflow.php
+++ b/tests/Fixtures/src/Workflow/ScalarEnumWorkflow.php
@@ -11,12 +11,12 @@
 
 namespace Temporal\Tests\Workflow;
 
-use Temporal\Workflow\WorkflowMethod;
-use Temporal\Workflow;
-use Temporal\Tests\Activity\SimpleActivity;
 use Temporal\Activity\ActivityOptions;
 use Temporal\Common\RetryOptions;
-use Temporal\Tests\Unit\DTO\Enum\ScalarEnum;
+use Temporal\Tests\Activity\SimpleActivity;
+use Temporal\Tests\Unit\DTO\Type\EnumType\ScalarEnum;
+use Temporal\Workflow;
+use Temporal\Workflow\WorkflowMethod;
 
 #[Workflow\WorkflowInterface]
 class ScalarEnumWorkflow
diff --git a/tests/Fixtures/src/Workflow/SimpleEnumWorkflow.php b/tests/Fixtures/src/Workflow/SimpleEnumWorkflow.php
index a5ecec1b..e078adcf 100644
--- a/tests/Fixtures/src/Workflow/SimpleEnumWorkflow.php
+++ b/tests/Fixtures/src/Workflow/SimpleEnumWorkflow.php
@@ -11,12 +11,12 @@
 
 namespace Temporal\Tests\Workflow;
 
-use Temporal\Workflow\WorkflowMethod;
-use Temporal\Workflow;
-use Temporal\Tests\Activity\SimpleActivity;
 use Temporal\Activity\ActivityOptions;
 use Temporal\Common\RetryOptions;
-use Temporal\Tests\Unit\DTO\Enum\SimpleEnum;
+use Temporal\Tests\Activity\SimpleActivity;
+use Temporal\Tests\Unit\DTO\Type\EnumType\SimpleEnum;
+use Temporal\Workflow;
+use Temporal\Workflow\WorkflowMethod;
 
 #[Workflow\WorkflowInterface]
 class SimpleEnumWorkflow
diff --git a/tests/Functional/Client/EnumTestCase.php b/tests/Functional/Client/EnumTestCase.php
index 574f4083..39f9d7c2 100644
--- a/tests/Functional/Client/EnumTestCase.php
+++ b/tests/Functional/Client/EnumTestCase.php
@@ -11,26 +11,19 @@
 
 namespace Temporal\Tests\Functional\Client;
 
-use Temporal\Tests\Workflow\SimpleEnumWorkflow;
-use Temporal\Tests\Unit\DTO\Enum\SimpleEnum;
+use Temporal\Tests\Unit\DTO\Type\EnumType\ScalarEnum;
+use Temporal\Tests\Unit\DTO\Type\EnumType\SimpleEnum;
 use Temporal\Tests\Workflow\ScalarEnumWorkflow;
-use Temporal\Tests\Unit\DTO\Enum\ScalarEnum;
+use Temporal\Tests\Workflow\SimpleEnumWorkflow;
 
 /**
  * @group client
  * @group functional
+ *
+ * @requires PHP >= 8.1
  */
 class EnumTestCase extends ClientTestCase
 {
-    public function setUp(): void
-    {
-        parent::setUp();
-        
-        if (PHP_VERSION_ID < 80104) {
-            $this->markTestSkipped();
-        }
-    }
-
     public function testSimpleEnum(): void
     {
         $client = $this->createClient();
diff --git a/tests/Unit/DTO/Enum/EnumTestCase.php b/tests/Unit/DTO/Enum/EnumTestCase.php
deleted file mode 100644
index 63e07984..00000000
--- a/tests/Unit/DTO/Enum/EnumTestCase.php
+++ /dev/null
@@ -1,32 +0,0 @@
-<?php
-
-/**
- * This file is part of Temporal package.
- *
- * For the full copyright and license information, please view the LICENSE
- * file that was distributed with this source code.
- */
-
-declare(strict_types=1);
-
-namespace Temporal\Tests\Unit\DTO\Enum;
-
-use Temporal\Tests\Unit\DTO\DTOMarshallingTestCase;
-
-class EnumTestCase extends DTOMarshallingTestCase
-{
-    public function testMarshalling(): void
-    {
-        if (PHP_VERSION_ID < 80104) {
-            $this->markTestSkipped();
-        }
-
-        $dto = new EnumDTO();
-        $dto->simpleEnum = SimpleEnum::TEST;
-        $dto->scalarEnum = ScalarEnum::TESTED_ENUM;
-
-        $result = $this->marshal($dto);
-        $this->assertEquals($dto->simpleEnum, $result['simpleEnum']);
-        $this->assertEquals($dto->scalarEnum, $result['scalarEnum']);
-    }
-}
diff --git a/tests/Unit/DTO/Readonly/ReadonlyPropertiesDTO.php b/tests/Unit/DTO/Readonly/ReadonlyPropertiesDTO.php
index fe106110..7301b4b9 100644
--- a/tests/Unit/DTO/Readonly/ReadonlyPropertiesDTO.php
+++ b/tests/Unit/DTO/Readonly/ReadonlyPropertiesDTO.php
@@ -11,8 +11,6 @@
 
 namespace Temporal\Tests\Unit\DTO\Readonly;
 
-use Temporal\Tests\Unit\DTO\Enum\ScalarEnum;
-
 class ReadonlyPropertiesDTO
 {
     readonly public string $propertiesString;
diff --git a/tests/Unit/DTO/Type/ArrayType/ArrayDTO.php b/tests/Unit/DTO/Type/ArrayType/ArrayDTO.php
new file mode 100644
index 00000000..bbc27ab2
--- /dev/null
+++ b/tests/Unit/DTO/Type/ArrayType/ArrayDTO.php
@@ -0,0 +1,32 @@
+<?php
+
+/**
+ * This file is part of Temporal package.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Temporal\Tests\Unit\DTO\Type\ArrayType;
+
+use Temporal\Internal\Marshaller\Meta\MarshalArray;
+
+class ArrayDTO
+{
+    #[MarshalArray(name: 'foo')]
+    public array $foo;
+
+    #[MarshalArray(name: 'bar')]
+    public ?array $bar;
+
+    #[MarshalArray(name: 'baz')]
+    public ?array $baz;
+
+    public array $autoArray;
+
+    public ?array $nullableFoo;
+
+    public ?array $nullableBar;
+}
diff --git a/tests/Unit/DTO/Type/ArrayType/ArrayTestCase.php b/tests/Unit/DTO/Type/ArrayType/ArrayTestCase.php
new file mode 100644
index 00000000..26aa0690
--- /dev/null
+++ b/tests/Unit/DTO/Type/ArrayType/ArrayTestCase.php
@@ -0,0 +1,57 @@
+<?php
+
+/**
+ * This file is part of Temporal package.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Temporal\Tests\Unit\DTO\Type\ArrayType;
+
+use Temporal\Tests\Unit\DTO\DTOMarshallingTestCase;
+
+class ArrayTestCase extends DTOMarshallingTestCase
+{
+    public function testMarshalling(): void
+    {
+        $dto = new ArrayDTO();
+        $dto->foo = ['foo'];
+        $dto->bar = ['bar'];
+        $dto->baz = null;
+        $dto->autoArray = ['foo'];
+        $dto->nullableFoo = ['bar'];
+        $dto->nullableBar = null;
+
+        $result = $this->marshal($dto);
+        $this->assertSame([
+            'foo' => ['foo'],
+            'bar' => ['bar'],
+            'baz' => null,
+            'autoArray' => ['foo'],
+            'nullableFoo' => ['bar'],
+            'nullableBar' => null,
+        ], $result);
+    }
+
+    public function testUnmarshalling(): void
+    {
+        $dto = $this->unmarshal([
+            'foo' => ['foo'],
+            'bar' => ['bar'],
+            'baz' => null,
+            'autoArray' => ['foo'],
+            'nullableFoo' => ['bar'],
+            'nullableBar' => null,
+        ], new ArrayDTO());
+
+        $this->assertSame(['foo'], $dto->foo);
+        $this->assertSame(['bar'], $dto->bar);
+        $this->assertSame(null, $dto->baz);
+        $this->assertSame(['foo'], $dto->autoArray);
+        $this->assertSame(['bar'], $dto->nullableFoo);
+        $this->assertSame(null, $dto->nullableBar);
+    }
+}
diff --git a/tests/Unit/DTO/Enum/EnumDTO.php b/tests/Unit/DTO/Type/EnumType/EnumDTO.php
similarity index 81%
rename from tests/Unit/DTO/Enum/EnumDTO.php
rename to tests/Unit/DTO/Type/EnumType/EnumDTO.php
index 6de9ef62..ed32b152 100644
--- a/tests/Unit/DTO/Enum/EnumDTO.php
+++ b/tests/Unit/DTO/Type/EnumType/EnumDTO.php
@@ -9,7 +9,7 @@
 
 declare(strict_types=1);
 
-namespace Temporal\Tests\Unit\DTO\Enum;
+namespace Temporal\Tests\Unit\DTO\Type\EnumType;
 
 use Temporal\Internal\Marshaller\Meta\Marshal;
 use Temporal\Internal\Marshaller\Type\EnumType;
@@ -21,4 +21,8 @@ class EnumDTO
 
     #[Marshal(name: 'scalarEnum', type: EnumType::class, of: ScalarEnum::class)]
     public ScalarEnum $scalarEnum;
+
+    public SimpleEnum $autoSimpleEnum;
+
+    public ScalarEnum $autoScalarEnum;
 }
diff --git a/tests/Unit/DTO/Type/EnumType/EnumTestCase.php b/tests/Unit/DTO/Type/EnumType/EnumTestCase.php
new file mode 100644
index 00000000..05210a46
--- /dev/null
+++ b/tests/Unit/DTO/Type/EnumType/EnumTestCase.php
@@ -0,0 +1,38 @@
+<?php
+
+/**
+ * This file is part of Temporal package.
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+declare(strict_types=1);
+
+namespace Temporal\Tests\Unit\DTO\Type\EnumType;
+
+use Temporal\Tests\Unit\DTO\DTOMarshallingTestCase;
+
+/**
+ * @requires PHP >= 8.1
+ */
+class EnumTestCase extends DTOMarshallingTestCase
+{
+    public function testUnmarshalBackedEnum(): void
+    {
+        $dto = $this->unmarshal([
+            'scalarEnum' => ScalarEnum::TESTED_ENUM->value,
+        ], new EnumDTO());
+
+        $this->assertSame(ScalarEnum::TESTED_ENUM, $dto->scalarEnum);
+    }
+
+    public function testUnmarshalNonBackedEnum(): void
+    {
+        $this->expectError();
+
+        $this->unmarshal([
+            'simpleEnum' => SimpleEnum::TEST->name,
+        ], new EnumDTO());
+    }
+}
diff --git a/tests/Unit/DTO/Enum/ScalarEnum.php b/tests/Unit/DTO/Type/EnumType/ScalarEnum.php
similarity index 84%
rename from tests/Unit/DTO/Enum/ScalarEnum.php
rename to tests/Unit/DTO/Type/EnumType/ScalarEnum.php
index 60ee9c97..9df53b3f 100644
--- a/tests/Unit/DTO/Enum/ScalarEnum.php
+++ b/tests/Unit/DTO/Type/EnumType/ScalarEnum.php
@@ -9,7 +9,7 @@
 
 declare(strict_types=1);
 
-namespace Temporal\Tests\Unit\DTO\Enum;
+namespace Temporal\Tests\Unit\DTO\Type\EnumType;
 
 enum ScalarEnum: string
 {
diff --git a/tests/Unit/DTO/Enum/SimpleEnum.php b/tests/Unit/DTO/Type/EnumType/SimpleEnum.php
similarity index 83%
rename from tests/Unit/DTO/Enum/SimpleEnum.php
rename to tests/Unit/DTO/Type/EnumType/SimpleEnum.php
index b1c20de7..2b3fb260 100644
--- a/tests/Unit/DTO/Enum/SimpleEnum.php
+++ b/tests/Unit/DTO/Type/EnumType/SimpleEnum.php
@@ -9,7 +9,7 @@
 
 declare(strict_types=1);
 
-namespace Temporal\Tests\Unit\DTO\Enum;
+namespace Temporal\Tests\Unit\DTO\Type\EnumType;
 
 enum SimpleEnum
 {