diff --git a/Machines/KeyboardMachine.hpp b/Machines/KeyboardMachine.hpp
index 375e95b1c..da911412b 100644
--- a/Machines/KeyboardMachine.hpp
+++ b/Machines/KeyboardMachine.hpp
@@ -10,6 +10,7 @@
 #define KeyboardMachine_h
 
 #include <cstdint>
+#include <string>
 
 #include "../Inputs/Keyboard.hpp"