diff --git a/include/emp/control/Signal.hpp b/include/emp/control/Signal.hpp
index d347df85e1..a6b4d36698 100644
--- a/include/emp/control/Signal.hpp
+++ b/include/emp/control/Signal.hpp
@@ -15,6 +15,7 @@
 #define EMP_CONTROL_SIGNAL_HPP_INCLUDE
 
 
+#include <cstdint>
 #include <map>
 #include <string>