diff --git a/presence/Makefile.am b/presence/Makefile.am
index 2ea4929..2a5976c 100644
--- a/presence/Makefile.am
+++ b/presence/Makefile.am
@@ -6,6 +6,7 @@
 
 phosphor_fan_presence_tach_SOURCES = \
 	fan.cpp \
+	gpio.cpp \
 	tach.cpp \
 	fan_enclosure.cpp \
 	tach_sensor.cpp \