--- a/shell/lean_js_main.cpp
+++ b/shell/lean_js_main.cpp
@@ -4,6 +4,7 @@ Released under Apache 2.0 license as described in the file LICENSE.
 
 Author: Leonardo de Moura
 */
+#include <cstdint>
 #include <iostream>
 #include <string>
 #include "shell/lean_js.h"