diff --git a/apps/metadata/nsf.c b/apps/metadata/nsf.c
index 58fc038b42..daffeb27ed 100644
--- a/apps/metadata/nsf.c
+++ b/apps/metadata/nsf.c
@@ -9,6 +9,7 @@
 #include "metadata_common.h"
 #include "metadata_parsers.h"
 #include "rbunicode.h"
+#include "string-extra.h"
 
 struct NESM_HEADER
 {