diff --git a/aster/window.h b/aster/window.h
index 7800017..1a06ac5 100644
--- a/aster/window.h
+++ b/aster/window.h
@@ -10,6 +10,7 @@
 #include "size.h"
 
 #include <EASTL/fixed_string.h>
+#include <atomic>
 
 struct Window final
 {