diff --git a/debug/null/hw-debug_sink.ads b/debug/null/hw-debug_sink.ads
new file mode 100644
index 0000000..dcd2dd1
--- /dev/null
+++ b/debug/null/hw-debug_sink.ads
@@ -0,0 +1,22 @@
+--
+-- Copyright (C) 2015 secunet Security Networks AG
+--
+-- This program is free software; you can redistribute it and/or modify
+-- it under the terms of the GNU General Public License as published by
+-- the Free Software Foundation; version 2 of the License.
+--
+-- This program is distributed in the hope that it will be useful,
+-- but WITHOUT ANY WARRANTY; without even the implied warranty of
+-- MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+-- GNU General Public License for more details.
+--
+
+package HW.Debug_Sink is
+
+   procedure Put (Item : String) is null;
+
+   procedure Put_Char (Item : Character) is null;
+
+   procedure New_Line is null;
+
+end HW.Debug_Sink;