diff --git a/src/DataView/DataView.php b/src/DataView/DataView.php
index 0ea5ef2..e418e62 100644
--- a/src/DataView/DataView.php
+++ b/src/DataView/DataView.php
@@ -70,8 +70,8 @@ class DataView {
      *   - ui: array - WordPress admin UI configuration
      *   - capability: string - required capability (default: 'manage_options')
      */
-    public function __construct( array $config ) {
-        $this->registry         = new FieldTypeRegistry();
+    public function __construct( array $config, ?FieldTypeRegistry $registry = null ) {
+        $this->registry         = $registry ?? new FieldTypeRegistry();
         $this->label_generator  = new LabelGenerator();
         $this->schema_generator = new SchemaGenerator( $this->registry );
 
diff --git a/tests/phpunit/data-view.php b/tests/phpunit/data-view.php
index 4926629..ff79edf 100644
--- a/tests/phpunit/data-view.php
+++ b/tests/phpunit/data-view.php
@@ -54,6 +54,78 @@ public function test_field_type_registry_has_default_types(): void {
         $this->assertTrue( $registry->has_type( 'datetime' ) );
     }
 
+    public function test_field_type_registry_has_custom_types(): void {
+        $registry_1 = new FieldTypeRegistry();
+        $registry_2 = new FieldTypeRegistry();
+
+        $registry_1->register_type( 'custom_type_1', [
+            'dataset'   => DataSet::TYPE_STRING,
+            'sanitizer' => fn( $value ) => ( $value ),
+            'schema'    => [],
+            'input'     => 'hidden',
+        ] );
+
+        $registry_2->register_type( 'custom_type_2', [
+            'dataset'   => DataSet::TYPE_INTEGER,
+            'sanitizer' => fn( $value ) => ( $value ),
+            'schema'    => [],
+            'input'     => 'hidden',
+        ] );
+
+        $this->assertTrue( $registry_1->has_type( 'custom_type_1' ) );
+        $this->assertTrue( $registry_2->has_type( 'custom_type_2' ) );
+
+        $this->assertFalse( $registry_1->has_type( 'custom_type_2' ) );
+        $this->assertFalse( $registry_2->has_type( 'custom_type_1' ) );
+
+        foreach( [
+            $registry_1,
+            $registry_2
+        ] as $registry ) {
+            // Check defaults are not erased by custom
+            $this->assertTrue( $registry->has_type( 'string' ) );
+            $this->assertTrue( $registry->has_type( 'text' ) );
+            $this->assertTrue( $registry->has_type( 'email' ) );
+            $this->assertTrue( $registry->has_type( 'url' ) );
+            $this->assertTrue( $registry->has_type( 'integer' ) );
+            $this->assertTrue( $registry->has_type( 'boolean' ) );
+            $this->assertTrue( $registry->has_type( 'date' ) );
+            $this->assertTrue( $registry->has_type( 'datetime' ) );
+        }
+    }
+
+    public function test_dataview_can_use_field_registery_with_custom_types(): void {
+        $registry = new FieldTypeRegistry();
+        $registry->register_type( 'custom_type', [
+            'dataset'   => DataSet::TYPE_STRING,
+            'sanitizer' => fn( $value ) => ( $value ),
+            'schema'    => [],
+            'input'     => 'hidden',
+        ] );
+
+        $config = [
+            'slug'   => 'dv_test_custom_field_type',
+            'label'  => 'Item',
+            'fields' => [
+                'name'   => 'custom_type',
+                'title'  => 'string',
+            ]
+        ];
+
+        try {
+            $view_default_registry = new DataView( $config );
+            $this->fail( 'Expected InvalidArgumentException was not thrown' );
+        } catch ( \InvalidArgumentException $e ) {
+            $this->assertStringStartsWith(
+                'Unknown field type "custom_type"',
+                $e->getMessage()
+            );
+        }
+
+        $view_custom_registry = new DataView( $config, $registry );
+        $this->assertInstanceOf( DataView::class, $view_custom_registry );
+    }
+
     public function test_field_type_registry_maps_to_dataset_types(): void {
         $registry = new FieldTypeRegistry();