diff --git a/include/xo/indentlog/timeutil/timeutil.hpp b/include/xo/indentlog/timeutil/timeutil.hpp
index 1a2a024..53a70f6 100644
--- a/include/xo/indentlog/timeutil/timeutil.hpp
+++ b/include/xo/indentlog/timeutil/timeutil.hpp
@@ -8,6 +8,7 @@
 # include <format>
 #endif
 #include <chrono>
+#include <compare>
 #include <cstdint>
 #include <time.h>