diff --git a/vstgui/uidescription-scripting/uiscripting.h b/vstgui/uidescription-scripting/uiscripting.h
index 8abe2a1c2..6091f70f0 100644
--- a/vstgui/uidescription-scripting/uiscripting.h
+++ b/vstgui/uidescription-scripting/uiscripting.h
@@ -9,6 +9,7 @@
 #include "../uidescription/iuidescription.h"
 #include "../uidescription/iuidescriptionaddon.h"
 #include <functional>
+#include <optional>
 #include <variant>
 
 //------------------------------------------------------------------------