diff --git a/library/include/larra/utils.hpp b/library/include/larra/utils.hpp
index 5d2898b..d053c82 100644
--- a/library/include/larra/utils.hpp
+++ b/library/include/larra/utils.hpp
@@ -163,7 +163,7 @@ struct FieldSetHelper {
             }())>
   static constexpr auto With(Self&& self, Value&& value) -> Type
     requires(
-        std::is_aggregate_v<Type> && (std::same_as<T, void> || requires { static_cast<T&>(self); }) &&
+        std::is_aggregate_v<Type> && (std::same_as<T, void> || requires { static_cast<const T&>(self); }) &&
         [] {
           if constexpr(I < boost::pfr::tuple_size_v<Type>) {
             return std::is_constructible_v<std::decay_t<decltype(boost::pfr::get<I>(std::declval<TT>()))>, decltype(value)>;