diff --git a/include/duplicatable_file_handle.hpp b/include/duplicatable_file_handle.hpp
index 5401e76..f199485 100644
--- a/include/duplicatable_file_handle.hpp
+++ b/include/duplicatable_file_handle.hpp
@@ -1,3 +1,5 @@
+#pragma once
+
 // SPDX-License-Identifier: Apache-2.0
 // SPDX-FileCopyrightText: Copyright OpenBMC Authors
 #include <unistd.h>