diff --git a/include/lexio/core.hpp b/include/lexio/core.hpp
index c68fadf..ae7f2fa 100644
--- a/include/lexio/core.hpp
+++ b/include/lexio/core.hpp
@@ -31,6 +31,7 @@
 
 #pragma once
 
+#include <algorithm>
 #include <cstdint>
 #include <stdexcept>
 #include <type_traits>