diff --git a/presence/Makefile.am b/presence/Makefile.am
index 2a5976c..33f13a3 100644
--- a/presence/Makefile.am
+++ b/presence/Makefile.am
@@ -5,6 +5,7 @@
 	phosphor-fan-presence-tach
 
 phosphor_fan_presence_tach_SOURCES = \
+	fallback.cpp \
 	fan.cpp \
 	gpio.cpp \
 	tach.cpp \