diff --git a/src/integrators/nfor.cpp b/src/integrators/nfor.cpp
index 269e9856..f23b9c18 100644
--- a/src/integrators/nfor.cpp
+++ b/src/integrators/nfor.cpp
@@ -2,6 +2,7 @@
 // Created by Mike Smith on 2022/1/10.
 //
 
+#include <gui/framerate.h>
 #include <util/imageio.h>
 #include <util/medium_tracker.h>
 #include <util/progress_bar.h>