diff --git a/src/timer/timer.h b/src/timer/timer.h
index d49d60aaff..b2af446ec7 100644
--- a/src/timer/timer.h
+++ b/src/timer/timer.h
@@ -11,6 +11,7 @@
 #define TIMER_H
 
 #include "timer_manager.h"
+#include <functional>
 
 
 /**