diff --git a/src/ystdlib/containers/Array.hpp b/src/ystdlib/containers/Array.hpp
index 38e2c50e..c46b49c9 100644
--- a/src/ystdlib/containers/Array.hpp
+++ b/src/ystdlib/containers/Array.hpp
@@ -1,5 +1,5 @@
-#ifndef YSTDLIB_CONTAINERS_ARRAY
-#define YSTDLIB_CONTAINERS_ARRAY
+#ifndef YSTDLIB_CONTAINERS_ARRAY_HPP
+#define YSTDLIB_CONTAINERS_ARRAY_HPP
 
 #include <algorithm>
 #include <concepts>
@@ -119,4 +119,4 @@ class Array {
 };
 }  // namespace ystdlib::containers
 
-#endif  // YSTDLIB_CONTAINERS_ARRAY
+#endif  // YSTDLIB_CONTAINERS_ARRAY_HPP