diff --git a/unittest/test_buttons.c b/unittest/test_buttons.c
index db63a29..b802305 100644
--- a/unittest/test_buttons.c
+++ b/unittest/test_buttons.c
@@ -1,5 +1,6 @@
 #include "test.h"
 #include "buttons.h"
+#include "relays.h"
 
 extern uint32_t mqtt_pub_count;
 extern uint32_t mqtt_sub_count;