diff --git a/ROADMAP.md b/ROADMAP.md
index 94c1dba..1c106e8 100644
--- a/ROADMAP.md
+++ b/ROADMAP.md
@@ -4,7 +4,6 @@
 
 - type conversions
 - non-linear search of methods/functions/...
-- register base types by `META_HPP_ENABLE_POLY_INFO`
 - fix all includes to work with the library more flexible
 - test and support shared libraries
 - remove `resolve_poly_type`, use `resolve_type(T&&)` instead
diff --git a/develop/manuals/meta_manuals/class_manual.cpp b/develop/manuals/meta_manuals/class_manual.cpp
index 897ab77..85e38c1 100644
--- a/develop/manuals/meta_manuals/class_manual.cpp
+++ b/develop/manuals/meta_manuals/class_manual.cpp
@@ -12,6 +12,7 @@
 namespace
 {
     class shape {
+        META_HPP_ENABLE_POLY_INFO()
     public:
         shape() = default;
         shape(const shape&) = default;
diff --git a/develop/manuals/meta_manuals/uvalue_manual.cpp b/develop/manuals/meta_manuals/uvalue_manual.cpp
index 0abf6c4..f4f3963 100644
--- a/develop/manuals/meta_manuals/uvalue_manual.cpp
+++ b/develop/manuals/meta_manuals/uvalue_manual.cpp
@@ -12,6 +12,7 @@
 namespace
 {
     class shape {
+        META_HPP_ENABLE_POLY_INFO()
     public:
         shape() = default;
         shape(const shape&) = default;
diff --git a/develop/singles/headers/meta.hpp/meta_all.hpp b/develop/singles/headers/meta.hpp/meta_all.hpp
index ecc6ae5..185589c 100644
--- a/develop/singles/headers/meta.hpp/meta_all.hpp
+++ b/develop/singles/headers/meta.hpp/meta_all.hpp
@@ -2561,10 +2561,6 @@ namespace meta_hpp
             return id_type{data_};
         }
 
-        [[nodiscard]] explicit operator id_type() const noexcept {
-            return get_id();
-        }
-
         [[nodiscard]] type_kind get_kind() const noexcept {
             return data_->kind;
         }
@@ -8307,19 +8303,19 @@ namespace meta_hpp::detail
     , size{class_traits<Class>::size}
     , align{class_traits<Class>::align}
     , argument_types{resolve_types(typename class_traits<Class>::argument_types{})} {
-        struct {
-            class_list base_classes;
-            deep_upcasts_t deep_upcasts;
-        } new_base_data;
+        class_list new_base_classes;
+        deep_upcasts_t new_deep_upcasts;
 
-        const auto add_new_base = [&new_base_data]<class_kind Base, class_kind Derived>(auto&& recur) {
+        const auto add_new_base = [&]<class_kind Base, class_kind Derived>(auto&& recur) {
             const class_type& base_class = resolve_type<Base>();
 
-            new_base_data.deep_upcasts.push_back(upcast_func_t{
-                .target{base_class},
+            new_deep_upcasts.push_back(upcast_func_t{
+                .target{base_class.get_id()},
                 .upcast{[]() {
                     if constexpr ( requires { static_cast<Base*>(std::declval<Class*>()); } ) {
-                        return +[](void* from) -> void* { return static_cast<Base*>(static_cast<Class*>(from)); };
+                        return +[](void* from) -> void* { //
+                            return static_cast<Base*>(static_cast<Class*>(from));
+                        };
                     } else {
                         return nullptr;
                     }
@@ -8327,16 +8323,16 @@ namespace meta_hpp::detail
             });
 
             if constexpr ( std::is_same_v<Class, Derived> ) {
-                new_base_data.base_classes.push_back(base_class);
+                new_base_classes.push_back(base_class);
             }
 
             recur.template operator()<Base>(recur);
         };
 
-        const auto add_new_bases = [&add_new_base]<class_kind Derived>(auto&& recur) {
+        const auto add_new_bases = [&]<class_kind Derived>(auto&& recur) {
             if constexpr ( check_base_info_enabled<Derived> ) {
                 using meta_base_info = typename Derived::meta_base_info;
-                meta_base_info::for_each([&add_new_base, &recur]<class_kind Base>() {
+                meta_base_info::for_each([&]<class_kind Base>() { //
                     add_new_base.template operator()<Base, Derived>(recur);
                 });
             } else {
@@ -8346,8 +8342,8 @@ namespace meta_hpp::detail
 
         add_new_bases.template operator()<Class>(add_new_bases);
 
-        base_classes.swap(new_base_data.base_classes);
-        deep_upcasts.swap(new_base_data.deep_upcasts);
+        base_classes.swap(new_base_classes);
+        deep_upcasts.swap(new_deep_upcasts);
     }
 }
 
diff --git a/headers/meta.hpp/meta_types.hpp b/headers/meta.hpp/meta_types.hpp
index 2ca2f45..a86ddae 100644
--- a/headers/meta.hpp/meta_types.hpp
+++ b/headers/meta.hpp/meta_types.hpp
@@ -126,10 +126,6 @@ namespace meta_hpp
             return id_type{data_};
         }
 
-        [[nodiscard]] explicit operator id_type() const noexcept {
-            return get_id();
-        }
-
         [[nodiscard]] type_kind get_kind() const noexcept {
             return data_->kind;
         }
diff --git a/headers/meta.hpp/meta_types/class_type.hpp b/headers/meta.hpp/meta_types/class_type.hpp
index 8c6710a..9bdbab9 100644
--- a/headers/meta.hpp/meta_types/class_type.hpp
+++ b/headers/meta.hpp/meta_types/class_type.hpp
@@ -27,19 +27,19 @@ namespace meta_hpp::detail
     , size{class_traits<Class>::size}
     , align{class_traits<Class>::align}
     , argument_types{resolve_types(typename class_traits<Class>::argument_types{})} {
-        struct {
-            class_list base_classes;
-            deep_upcasts_t deep_upcasts;
-        } new_base_data;
+        class_list new_base_classes;
+        deep_upcasts_t new_deep_upcasts;
 
-        const auto add_new_base = [&new_base_data]<class_kind Base, class_kind Derived>(auto&& recur) {
+        const auto add_new_base = [&]<class_kind Base, class_kind Derived>(auto&& recur) {
             const class_type& base_class = resolve_type<Base>();
 
-            new_base_data.deep_upcasts.push_back(upcast_func_t{
-                .target{base_class},
+            new_deep_upcasts.push_back(upcast_func_t{
+                .target{base_class.get_id()},
                 .upcast{[]() {
                     if constexpr ( requires { static_cast<Base*>(std::declval<Class*>()); } ) {
-                        return +[](void* from) -> void* { return static_cast<Base*>(static_cast<Class*>(from)); };
+                        return +[](void* from) -> void* { //
+                            return static_cast<Base*>(static_cast<Class*>(from));
+                        };
                     } else {
                         return nullptr;
                     }
@@ -47,16 +47,16 @@ namespace meta_hpp::detail
             });
 
             if constexpr ( std::is_same_v<Class, Derived> ) {
-                new_base_data.base_classes.push_back(base_class);
+                new_base_classes.push_back(base_class);
             }
 
             recur.template operator()<Base>(recur);
         };
 
-        const auto add_new_bases = [&add_new_base]<class_kind Derived>(auto&& recur) {
+        const auto add_new_bases = [&]<class_kind Derived>(auto&& recur) {
             if constexpr ( check_base_info_enabled<Derived> ) {
                 using meta_base_info = typename Derived::meta_base_info;
-                meta_base_info::for_each([&add_new_base, &recur]<class_kind Base>() {
+                meta_base_info::for_each([&]<class_kind Base>() { //
                     add_new_base.template operator()<Base, Derived>(recur);
                 });
             } else {
@@ -66,8 +66,8 @@ namespace meta_hpp::detail
 
         add_new_bases.template operator()<Class>(add_new_bases);
 
-        base_classes.swap(new_base_data.base_classes);
-        deep_upcasts.swap(new_base_data.deep_upcasts);
+        base_classes.swap(new_base_classes);
+        deep_upcasts.swap(new_deep_upcasts);
     }
 }