diff --git a/src/bin/ui/ui.c b/src/bin/ui/ui.c
index e7af7ce..acce615 100644
--- a/src/bin/ui/ui.c
+++ b/src/bin/ui/ui.c
@@ -107,7 +107,7 @@ evisum_size_format(unsigned long value)
    return s;
 }
 
-char *
+static char *
 _path_append(const char *path, const char *file)
 {
    char *concat;