--- a/src/quo-private.h	2026-04-20 15:10:50.306375540 +0200
+++ b/src/quo-private.h	2026-04-20 15:11:02.249241749 +0200
@@ -25,6 +25,7 @@
 #ifdef HAVE_STDBOOL_H
 #include <stdbool.h>
 #endif
+#include <sys/types.h>
 
 /** Library version. */
 #define QUO_VER    QUO_VERSION_CURRENT