diff --git a/src/interfaces/writablestream.js b/src/interfaces/writablestream.js
index <HASH>..<HASH> 100644
--- a/src/interfaces/writablestream.js
+++ b/src/interfaces/writablestream.js
@@ -6,6 +6,7 @@
 "use strict";
 /*global _gpfDefineInterface*/ // Internal interface definition helper
 /*global _gpfSyncReadSourceJSON*/ // Reads a source json file (only in source mode)
+/*exported _gpfIWritableStream*/ // gpf.interfaces.IWritableStream
 /*#endif*/
 
 /**
@@ -24,4 +25,10 @@
  * @since 0.1.9
  */
 
-_gpfDefineInterface("WritableStream", _gpfSyncReadSourceJSON("interfaces/writablestream.json"));
+/**
+ * IWritableStream interface specifier
+ *
+ * @type {gpf.interfaces.IWritableStream}
+ */
+var _gpfIWritableStream = _gpfDefineInterface("WritableStream",
+    _gpfSyncReadSourceJSON("interfaces/writablestream.json"));
export _gpfIWritableStream