diff --git a/src/Parser/TypeSchema/BCLayer.php b/src/Parser/TypeSchema/BCLayer.php
index f176c542..512eea03 100644
--- a/src/Parser/TypeSchema/BCLayer.php
+++ b/src/Parser/TypeSchema/BCLayer.php
@@ -52,6 +52,10 @@ public static function transformDefinition(\stdClass $data): \stdClass
             $data->type = 'struct';
         }
 
+        if (isset($data->{'x-psx-mapping'}) && $data->{'x-psx-mapping'} instanceof \stdClass) {
+            $data->{'x-psx-mapping'} = (array) $data->{'x-psx-mapping'};
+        }
+
         if (!isset($data->type)) {
             if (isset($data->additionalProperties) || isset($data->schema)) {
                 $data->type = 'map';
diff --git a/tests/Parser/TypeSchema/test_schema.json b/tests/Parser/TypeSchema/test_schema.json
index 7b6ec964..b603b821 100644
--- a/tests/Parser/TypeSchema/test_schema.json
+++ b/tests/Parser/TypeSchema/test_schema.json
@@ -30,7 +30,8 @@
           "type": "reference",
           "target": "Location"
         }
-      }
+      },
+      "x-psx-class": "PSX\\Schema\\Tests\\Parser\\Popo\\Author"
     },
     "Location": {
       "description": "Location of the person",
@@ -42,13 +43,15 @@
         "long": {
           "type": "number"
         }
-      }
+      },
+      "x-psx-class": "PSX\\Schema\\Tests\\Parser\\Popo\\Location"
     },
     "Meta": {
       "type": "object",
       "additionalProperties": {
         "type": "string"
-      }
+      },
+      "x-psx-class": "PSX\\Schema\\Tests\\Parser\\Popo\\Meta"
     },
     "News": {
       "description": "An general news entry",
@@ -133,6 +136,10 @@
         "payload": {
           "type": "any"
         }
+      },
+      "x-psx-class": "PSX\\Schema\\Tests\\Parser\\Popo\\News",
+      "x-psx-mapping": {
+        "g-recaptcha-response": "captcha"
       }
     }
   },
diff --git a/tests/Parser/TypeSchemaTest.php b/tests/Parser/TypeSchemaTest.php
index 74dc3fd8..b316f00c 100644
--- a/tests/Parser/TypeSchemaTest.php
+++ b/tests/Parser/TypeSchemaTest.php
@@ -47,6 +47,7 @@ public function testParse()
         $schema = $parser->parse(__DIR__ . '/TypeSchema/test_schema.json');
 
         $this->assertSchema($this->getSchema(), $schema);
+        $this->assertSchemaAttributes($this->getSchema(), $schema);
     }
 
     public function testParseTypeSchema()
diff --git a/tests/SchemaTestCase.php b/tests/SchemaTestCase.php
index 1313e9a6..e9754a60 100644
--- a/tests/SchemaTestCase.php
+++ b/tests/SchemaTestCase.php
@@ -22,6 +22,7 @@
 
 use PHPUnit\Framework\TestCase;
 use PSX\Schema\Generator\TypeSchema;
+use PSX\Schema\SchemaInterface;
 use PSX\Schema\SchemaManager;
 
 /**
@@ -40,12 +41,12 @@ protected function setUp(): void
         $this->schemaManager = new SchemaManager();
     }
 
-    protected function getSchema()
+    protected function getSchema(): SchemaInterface
     {
         return $this->schemaManager->getSchema(TestSchema::class);
     }
 
-    protected function assertSchema($leftSchema, $rightSchema)
+    protected function assertSchema(SchemaInterface $leftSchema, SchemaInterface $rightSchema): void
     {
         $generator = new TypeSchema();
 
@@ -54,4 +55,12 @@ protected function assertSchema($leftSchema, $rightSchema)
 
         $this->assertJsonStringEqualsJsonString($expect, $actual);
     }
+
+    protected function assertSchemaAttributes(SchemaInterface $leftSchema, SchemaInterface $rightSchema): void
+    {
+        foreach ($leftSchema->getDefinitions()->getTypes() as $typeName => $leftType) {
+            $rightType = $rightSchema->getDefinitions()->getType($typeName);
+            $this->assertSame($leftType->getAttributes(), $rightType->getAttributes());
+        }
+    }
 }