diff --git a/mk/make.inc b/mk/make.inc
index f846edf615..7baf186eba 100644
--- a/mk/make.inc
+++ b/mk/make.inc
@@ -10,3 +10,4 @@ LIBRARIES += AP_Airspeed
 LIBRARIES += AP_Relay
 LIBRARIES += AP_ServoRelayEvents
 LIBRARIES += AP_Volz_Protocol
+LIBRARIES += AP_SBusOut