diff --git a/lib/src/query.c b/lib/src/query.c
index 23fd4edc..7fad2284 100644
--- a/lib/src/query.c
+++ b/lib/src/query.c
@@ -4,6 +4,7 @@
 #include "./bits.h"
 #include "./point.h"
 #include "./tree_cursor.h"
+#include "./unicode.h"
 #include <wctype.h>
 
 /*