diff --git a/app/src/lock_util.c b/app/src/lock_util.c
index 67183d7..723d3b1 100644
--- a/app/src/lock_util.c
+++ b/app/src/lock_util.c
@@ -1,3 +1,4 @@
+#include <lock_util.h>
 #include <stdlib.h>
 #include <SDL2/SDL_mutex.h>