diff --git a/map/src/map.hpp b/map/src/map.hpp
index 9a39ea1..6824403 100644
--- a/map/src/map.hpp
+++ b/map/src/map.hpp
@@ -8,8 +8,10 @@
 #include <cassert>
 #include <cstddef>
 #include <functional>
+#ifndef NDEBUG
 #include <queue>   // only for debug use
 #include <vector>  // only for debug use
+#endif
 #include "exceptions.hpp"
 #include "utility.hpp"