diff --git a/inc/app_utils.hpp b/inc/app_utils.hpp
index 844f6b1..9b8ce58 100644
--- a/inc/app_utils.hpp
+++ b/inc/app_utils.hpp
@@ -1,7 +1,9 @@
 #pragma once
 
+#include <cstddef>
 #include <cstdint>
 #include <span>
+#include <type_traits>
 #include <utility>
 #include <version>
 #ifdef __cpp_lib_format