--- a/lib/Protobuf-PHP/library/DrSlump/Protobuf/CodecInterface.php
+++ b/lib/Protobuf-PHP/library/DrSlump/Protobuf/CodecInterface.php
@@ -1,1 +1,9 @@
+<?php
 
+namespace DrSlump\Protobuf;
+
+interface CodecInterface
+{
+    public function encode(\DrSlump\Protobuf\Message $message);
+    public function decode(\DrSlump\Protobuf\Message $message, $data);
+}