diff --git a/payload_constants.cc b/payload_constants.cc
new file mode 100644
index 0000000..2fc31e3
--- /dev/null
+++ b/payload_constants.cc
@@ -0,0 +1,12 @@
+// Copyright 2014 The Chromium OS Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#include "update_engine/payload_constants.h"
+
+namespace chromeos_update_engine {
+
+const char kDeltaMagic[] = "CrAU";
+const char kBspatchPath[] = "bspatch";
+
+};  // namespace chromeos_update_engine