diff --git a/include/libcamera/ipa/ipa_interface.h b/include/libcamera/ipa/ipa_interface.h
index 50ca0e7b..8afcfe21 100644
--- a/include/libcamera/ipa/ipa_interface.h
+++ b/include/libcamera/ipa/ipa_interface.h
@@ -13,6 +13,7 @@
 #include <map>
 #include <vector>
 
+#include <libcamera/base/flags.h>
 #include <libcamera/base/signal.h>
 
 #include <libcamera/controls.h>