diff --git a/headers/meta.hpp/meta_base.hpp b/headers/meta.hpp/meta_base.hpp
index 45ab91a..7068549 100644
--- a/headers/meta.hpp/meta_base.hpp
+++ b/headers/meta.hpp/meta_base.hpp
@@ -47,7 +47,7 @@ namespace meta_hpp
     }
 
     template < typename Signature, typename Class >
-    constexpr auto select(Signature Class::*func) -> decltype(func) {
+    constexpr auto select(Signature Class::*func) noexcept -> Signature Class::* {
         return func;
     }
 
diff --git a/headers/meta.hpp/meta_registry.hpp b/headers/meta.hpp/meta_registry.hpp
index a5b8448..47efb89 100644
--- a/headers/meta.hpp/meta_registry.hpp
+++ b/headers/meta.hpp/meta_registry.hpp
@@ -9,6 +9,37 @@
 #include "meta_base.hpp"
 #include "meta_states.hpp"
 
+namespace meta_hpp::detail
+{
+    template < typename Class, typename... Args >
+    concept class_bind_ctor_kind =
+        class_kind<Class> &&
+        requires(Args&&... args) { { Class{std::forward<Args>(args)...} }; };
+
+    template < typename Class, typename Base >
+    concept class_bind_base_kind =
+        class_kind<Class> && class_kind<Base> &&
+        stdex::derived_from<Class, Base>;
+
+    template < typename Class, typename Function >
+    concept class_bind_function_kind =
+        class_kind<Class> && function_kind<Function>;
+
+    template < typename Class, typename Member >
+    concept class_bind_member_kind =
+        class_kind<Class> && member_kind<Member> &&
+        stdex::same_as<Class, typename member_traits<Member>::class_type>;
+
+    template < typename Class, typename Method >
+    concept class_bind_method_kind =
+        class_kind<Class> && method_kind<Method> &&
+        stdex::same_as<Class, typename method_traits<Method>::class_type>;
+
+    template < typename Class, typename Pointer >
+    concept class_bind_variable_kind =
+        class_kind<Class> && pointer_kind<Pointer>;
+}
+
 namespace meta_hpp
 {
     template < detail::class_kind Class >
@@ -18,21 +49,27 @@ namespace meta_hpp
         operator class_type() const noexcept;
 
         template < typename... Args >
+            requires detail::class_bind_ctor_kind<Class, Args...>
         class_bind& ctor_();
 
         template < detail::class_kind Base >
+            requires detail::class_bind_base_kind<Class, Base>
         class_bind& base_();
 
         template < detail::function_kind Function >
+            requires detail::class_bind_function_kind<Class, Function>
         class_bind& function_(std::string name, Function function);
 
         template < detail::member_kind Member >
+            requires detail::class_bind_member_kind<Class, Member>
         class_bind& member_(std::string name, Member member);
 
         template < detail::method_kind Method >
+            requires detail::class_bind_method_kind<Class, Method>
         class_bind& method_(std::string name, Method method);
 
         template < detail::pointer_kind Pointer >
+            requires detail::class_bind_variable_kind<Class, Pointer>
         class_bind& variable_(std::string name, Pointer pointer);
     private:
         detail::class_type_data_ptr data_;
diff --git a/headers/meta.hpp/meta_registry/class_bind.hpp b/headers/meta.hpp/meta_registry/class_bind.hpp
index 81dce45..9dc1554 100644
--- a/headers/meta.hpp/meta_registry/class_bind.hpp
+++ b/headers/meta.hpp/meta_registry/class_bind.hpp
@@ -22,8 +22,8 @@ namespace meta_hpp
 
     template < detail::class_kind Class >
     template < typename... Args >
+        requires detail::class_bind_ctor_kind<Class, Args...>
     class_bind<Class>& class_bind<Class>::ctor_() {
-        static_assert(detail::stdex::constructible_from<Class, Args...>);
         auto ctor_state = detail::ctor_state::make<Class, Args...>();
         data_->ctors.emplace(ctor_state->index, std::move(ctor_state));
         return *this;
@@ -31,8 +31,8 @@ namespace meta_hpp
 
     template < detail::class_kind Class >
     template < detail::class_kind Base >
+        requires detail::class_bind_base_kind<Class, Base>
     class_bind<Class>& class_bind<Class>::base_() {
-        static_assert(detail::stdex::derived_from<Class, Base>);
         data_->bases.emplace(resolve_type<Base>());
         data_->bases_info.emplace(resolve_type<Base>(), detail::class_type_data::base_info{
             .upcast = +[](void* derived) -> void* {
@@ -44,6 +44,7 @@ namespace meta_hpp
 
     template < detail::class_kind Class >
     template < detail::function_kind Function >
+        requires detail::class_bind_function_kind<Class, Function>
     class_bind<Class>& class_bind<Class>::function_(std::string name, Function function) {
         auto function_state = detail::function_state::make<Function>(std::move(name), std::move(function));
         data_->functions.emplace(function_state->index, std::move(function_state));
@@ -52,8 +53,8 @@ namespace meta_hpp
 
     template < detail::class_kind Class >
     template < detail::member_kind Member >
+        requires detail::class_bind_member_kind<Class, Member>
     class_bind<Class>& class_bind<Class>::member_(std::string name, Member member) {
-        static_assert(std::is_same_v<Class, typename detail::member_traits<Member>::class_type>);
         auto member_state = detail::member_state::make<Member>(std::move(name), std::move(member));
         data_->members.emplace(member_state->index, std::move(member_state));
         return *this;
@@ -61,8 +62,8 @@ namespace meta_hpp
 
     template < detail::class_kind Class >
     template < detail::method_kind Method >
+        requires detail::class_bind_method_kind<Class, Method>
     class_bind<Class>& class_bind<Class>::method_(std::string name, Method method) {
-        static_assert(std::is_same_v<Class, typename detail::method_traits<Method>::class_type>);
         auto method_state = detail::method_state::make<Method>(std::move(name), std::move(method));
         data_->methods.emplace(method_state->index, std::move(method_state));
         return *this;
@@ -70,6 +71,7 @@ namespace meta_hpp
 
     template < detail::class_kind Class >
     template < detail::pointer_kind Pointer >
+        requires detail::class_bind_variable_kind<Class, Pointer>
     class_bind<Class>& class_bind<Class>::variable_(std::string name, Pointer pointer) {
         auto variable_state = detail::variable_state::make<Pointer>(std::move(name), std::move(pointer));
         data_->variables.emplace(variable_state->index, std::move(variable_state));
diff --git a/untests/meta_states/function_tests.cpp b/untests/meta_states/function_tests.cpp
index a5b24bc..f58b630 100644
--- a/untests/meta_states/function_tests.cpp
+++ b/untests/meta_states/function_tests.cpp
@@ -122,7 +122,7 @@ TEST_CASE("meta/meta_states/function") {
 
         CHECK(func.is_invocable_with<int*>());
         CHECK(func.is_invocable_with<const int*>());
-        CHECK(func.is_invocable_with<nullptr_t>());
+        CHECK(func.is_invocable_with<std::nullptr_t>());
 
         int i{42};
         CHECK(func.invoke(&i) == false);
diff --git a/untests/meta_types/any_type_tests.cpp b/untests/meta_types/any_type_tests.cpp
index bf04fa7..2bf6c88 100644
--- a/untests/meta_types/any_type_tests.cpp
+++ b/untests/meta_types/any_type_tests.cpp
@@ -174,8 +174,8 @@ TEST_CASE("meta/meta_types/any_type") {
         const meta::any_type& type = meta::resolve_type(nullptr);
 
         REQUIRE(type);
-        REQUIRE(type == meta::resolve_type<nullptr_t>());
-        REQUIRE(type.get_id() == meta::resolve_type<nullptr_t>().get_id());
+        REQUIRE(type == meta::resolve_type<std::nullptr_t>());
+        REQUIRE(type.get_id() == meta::resolve_type<std::nullptr_t>().get_id());
 
         CHECK(type.is_nullptr());
         CHECK(type.get_kind() == meta::type_kind::nullptr_);
diff --git a/untests/meta_utilities/arg7_tests.cpp b/untests/meta_utilities/arg7_tests.cpp
index 2fed809..bd515b9 100644
--- a/untests/meta_utilities/arg7_tests.cpp
+++ b/untests/meta_utilities/arg7_tests.cpp
@@ -134,22 +134,22 @@ TEST_CASE("meta/meta_utilities/arg7/cast/from_nullptr") {
     using meta::detail::arg;
 
     SUBCASE("nullptr -> *") {
-        static_assert(std::is_invocable_v<void(int*), nullptr_t>);
-        static_assert(std::is_invocable_v<void(int*), nullptr_t&>);
-        static_assert(std::is_invocable_v<void(int*), nullptr_t&&>);
-        static_assert(std::is_invocable_v<void(int*), const nullptr_t>);
-        static_assert(std::is_invocable_v<void(int*), const nullptr_t&>);
-        static_assert(std::is_invocable_v<void(int*), const nullptr_t&&>);
+        static_assert(std::is_invocable_v<void(int*), std::nullptr_t>);
+        static_assert(std::is_invocable_v<void(int*), std::nullptr_t&>);
+        static_assert(std::is_invocable_v<void(int*), std::nullptr_t&&>);
+        static_assert(std::is_invocable_v<void(int*), const std::nullptr_t>);
+        static_assert(std::is_invocable_v<void(int*), const std::nullptr_t&>);
+        static_assert(std::is_invocable_v<void(int*), const std::nullptr_t&&>);
 
-        static_assert(std::is_invocable_v<void(const D*), nullptr_t>);
-        static_assert(std::is_invocable_v<void(const D*), nullptr_t&>);
-        static_assert(std::is_invocable_v<void(const D*), nullptr_t&&>);
-        static_assert(std::is_invocable_v<void(const D*), const nullptr_t>);
-        static_assert(std::is_invocable_v<void(const D*), const nullptr_t&>);
-        static_assert(std::is_invocable_v<void(const D*), const nullptr_t&&>);
+        static_assert(std::is_invocable_v<void(const D*), std::nullptr_t>);
+        static_assert(std::is_invocable_v<void(const D*), std::nullptr_t&>);
+        static_assert(std::is_invocable_v<void(const D*), std::nullptr_t&&>);
+        static_assert(std::is_invocable_v<void(const D*), const std::nullptr_t>);
+        static_assert(std::is_invocable_v<void(const D*), const std::nullptr_t&>);
+        static_assert(std::is_invocable_v<void(const D*), const std::nullptr_t&&>);
 
-        nullptr_t n1{nullptr};
-        const nullptr_t n2{nullptr};
+        std::nullptr_t n1{nullptr};
+        const std::nullptr_t n2{nullptr};
 
         CHECK(arg{n1}.can_cast_to<int*>());
         CHECK(arg{std::move(n1)}.can_cast_to<int*>());