diff --git a/libs/surfaces/mackie/mackie_control_protocol.h b/libs/surfaces/mackie/mackie_control_protocol.h
index 2399e099d2..cecfc5ea6c 100644
--- a/libs/surfaces/mackie/mackie_control_protocol.h
+++ b/libs/surfaces/mackie/mackie_control_protocol.h
@@ -26,6 +26,8 @@
 
 #include <glibmm/thread.h>
 
+#include "pbd/abstract_ui.h"
+
 #include "ardour/types.h"
 #include "ardour/midi_ui.h"
 #include "midi++/types.h"