diff --git a/lib/map.h b/lib/map.h
index 0223475e9de..7128d9dbb77 100644
--- a/lib/map.h
+++ b/lib/map.h
@@ -17,6 +17,7 @@ limitations under the License.
 #ifndef LIB_MAP_H_
 #define LIB_MAP_H_
 
+#include <iterator>
 #include <optional>
 
 /// Given a map and a key, return the value corresponding to the key in the map,