diff --git a/inc/wofi.h b/inc/wofi.h
index a21c0ce..df42256 100644
--- a/inc/wofi.h
+++ b/inc/wofi.h
@@ -16,6 +16,7 @@
  */
 
 #ifndef WAIFU_H
+#define WAIFU_H
 
 #include <map.h>
 #include <config.h>