diff --git a/lib/include/prjxray/memory_mapped_file.h b/lib/include/prjxray/memory_mapped_file.h
index 6aeb82108..81f8dd726 100644
--- a/lib/include/prjxray/memory_mapped_file.h
+++ b/lib/include/prjxray/memory_mapped_file.h
@@ -12,6 +12,7 @@
 
 #include <memory>
 #include <string>
+#include <cstdint>
 
 #include <absl/types/span.h>