diff --git a/headers/meta.hpp/meta_all.hpp b/headers/meta.hpp/meta_all.hpp
index f2adc16..1d7fa5c 100644
--- a/headers/meta.hpp/meta_all.hpp
+++ b/headers/meta.hpp/meta_all.hpp
@@ -6,4 +6,19 @@
 
 #pragma once
 
-#include "meta_fwd.hpp"
+#include "meta_base.hpp"
+
+#include "meta_kinds.hpp"
+
+#include "meta_traits.hpp"
+#include "meta_traits/array_traits.hpp"
+#include "meta_traits/class_traits.hpp"
+#include "meta_traits/ctor_traits.hpp"
+#include "meta_traits/enum_traits.hpp"
+#include "meta_traits/function_traits.hpp"
+#include "meta_traits/member_traits.hpp"
+#include "meta_traits/method_traits.hpp"
+#include "meta_traits/number_traits.hpp"
+#include "meta_traits/pointer_traits.hpp"
+#include "meta_traits/reference_traits.hpp"
+#include "meta_traits/void_traits.hpp"
diff --git a/headers/meta.hpp/meta_base.hpp b/headers/meta.hpp/meta_base.hpp
new file mode 100644
index 0000000..fbff63e
--- /dev/null
+++ b/headers/meta.hpp/meta_base.hpp
@@ -0,0 +1,182 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#pragma once
+
+#include <cassert>
+#include <cstddef>
+#include <cstdint>
+
+#include <algorithm>
+#include <any>
+#include <array>
+#include <atomic>
+#include <concepts>
+#include <functional>
+#include <initializer_list>
+#include <iosfwd>
+#include <map>
+#include <memory>
+#include <optional>
+#include <set>
+#include <stdexcept>
+#include <string_view>
+#include <string>
+#include <tuple>
+#include <type_traits>
+#include <utility>
+#include <vector>
+
+#include <enum.hpp/enum.hpp>
+#include <enum.hpp/enum_bitflags.hpp>
+
+namespace meta_hpp
+{
+    template < typename Enum >
+    using bitflags = enum_hpp::bitflags::bitflags<Enum>;
+}
+
+namespace meta_hpp
+{
+    template < typename... Types >
+    struct type_list {};
+
+    template < std::size_t Index, typename TypeList >
+    struct type_list_at;
+
+    template < std::size_t Index, typename... Types >
+    struct type_list_at<Index, type_list<Types...>> {
+        using type = std::tuple_element_t<Index, std::tuple<Types...>>;
+    };
+
+    template < std::size_t Index, typename TypeList >
+    using type_list_at_t = typename type_list_at<Index, TypeList>::type;
+}
+
+namespace meta_hpp
+{
+    template < typename Signature >
+    constexpr auto select(Signature* func) noexcept -> Signature* {
+        return func;
+    }
+
+    template < typename Signature, typename Class >
+    constexpr auto select(Signature Class::*func) -> decltype(func) {
+        return func;
+    }
+}
+
+namespace meta_hpp
+{
+    class value;
+
+    namespace detail
+    {
+        class arg_base;
+        class arg;
+
+        class inst_base;
+        class inst;
+    }
+}
+
+namespace meta_hpp
+{
+    class ctor;
+    class evalue;
+    class function;
+    class member;
+    class method;
+    class scope;
+    class variable;
+
+    namespace detail
+    {
+        struct ctor_state;
+        struct evalue_state;
+        struct function_state;
+        struct member_state;
+        struct method_state;
+        struct scope_state;
+        struct variable_state;
+
+        using ctor_state_ptr = std::shared_ptr<ctor_state>;
+        using evalue_state_ptr = std::shared_ptr<evalue_state>;
+        using function_state_ptr = std::shared_ptr<function_state>;
+        using member_state_ptr = std::shared_ptr<member_state>;
+        using method_state_ptr = std::shared_ptr<method_state>;
+        using scope_state_ptr = std::shared_ptr<scope_state>;
+        using variable_state_ptr = std::shared_ptr<variable_state>;
+    }
+}
+
+namespace meta_hpp
+{
+    class any_type;
+    class array_type;
+    class class_type;
+    class ctor_type;
+    class enum_type;
+    class function_type;
+    class member_type;
+    class method_type;
+    class number_type;
+    class pointer_type;
+    class reference_type;
+    class void_type;
+
+    namespace detail
+    {
+        struct type_data_base;
+        struct array_type_data;
+        struct class_type_data;
+        struct ctor_type_data;
+        struct enum_type_data;
+        struct function_type_data;
+        struct member_type_data;
+        struct method_type_data;
+        struct number_type_data;
+        struct pointer_type_data;
+        struct reference_type_data;
+        struct void_type_data;
+
+        using type_data_base_ptr = std::shared_ptr<type_data_base>;
+        using array_type_data_ptr = std::shared_ptr<array_type_data>;
+        using class_type_data_ptr = std::shared_ptr<class_type_data>;
+        using ctor_type_data_ptr = std::shared_ptr<ctor_type_data>;
+        using enum_type_data_ptr = std::shared_ptr<enum_type_data>;
+        using function_type_data_ptr = std::shared_ptr<function_type_data>;
+        using member_type_data_ptr = std::shared_ptr<member_type_data>;
+        using method_type_data_ptr = std::shared_ptr<method_type_data>;
+        using number_type_data_ptr = std::shared_ptr<number_type_data>;
+        using pointer_type_data_ptr = std::shared_ptr<pointer_type_data>;
+        using reference_type_data_ptr = std::shared_ptr<reference_type_data>;
+        using void_type_data_ptr = std::shared_ptr<void_type_data>;
+    }
+}
+
+namespace meta_hpp
+{
+    struct ctor_index;
+    struct evalue_index;
+    struct function_index;
+    struct member_index;
+    struct method_index;
+    struct variable_index;
+
+    using class_set = std::set<class_type, std::less<>>;
+    using class_map = std::map<std::string, class_type, std::less<>>;
+
+    using enum_set = std::set<enum_type, std::less<>>;
+    using enum_map = std::map<std::string, enum_type, std::less<>>;
+
+    using ctor_map = std::map<ctor_index, ctor, std::less<>>;
+    using evalue_map = std::map<evalue_index, evalue, std::less<>>;
+    using function_map = std::map<function_index, function, std::less<>>;
+    using member_map = std::map<member_index, member, std::less<>>;
+    using method_map = std::map<method_index, method, std::less<>>;
+    using variable_map = std::map<variable_index, variable, std::less<>>;
+}
diff --git a/headers/meta.hpp/meta_kinds.hpp b/headers/meta.hpp/meta_kinds.hpp
new file mode 100644
index 0000000..3aa55fb
--- /dev/null
+++ b/headers/meta.hpp/meta_kinds.hpp
@@ -0,0 +1,154 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#pragma once
+
+#include "meta_base.hpp"
+
+namespace meta_hpp
+{
+    template < typename T >
+    concept array_kind = std::is_array_v<T>;
+
+    template < typename T >
+    concept class_kind = std::is_class_v<T>;
+
+    template < typename T >
+    concept enum_kind = std::is_enum_v<T>;
+
+    template < typename T >
+    concept function_kind = std::is_pointer_v<T> && std::is_function_v<std::remove_pointer_t<T>>;
+
+    template < typename T >
+    concept member_kind = std::is_member_object_pointer_v<T>;
+
+    template < typename T >
+    concept method_kind = std::is_member_function_pointer_v<T>;
+
+    template < typename T >
+    concept number_kind = std::is_arithmetic_v<T>;
+
+    template < typename T >
+    concept pointer_kind = std::is_pointer_v<T> && !std::is_function_v<std::remove_pointer_t<T>>;
+
+    template < typename T >
+    concept reference_kind = std::is_reference_v<T>;
+
+    template < typename T >
+    concept void_kind = std::is_void_v<T>;
+}
+
+namespace meta_hpp
+{
+    enum class type_kind : std::uint32_t {
+        array_,
+        class_,
+        ctor_,
+        enum_,
+        function_,
+        member_,
+        method_,
+        number_,
+        pointer_,
+        reference_,
+        void_,
+    };
+
+    template < typename T >
+    constexpr type_kind make_type_kind() noexcept {
+        if constexpr ( array_kind<T> ) { return type_kind::array_; }
+        if constexpr ( class_kind<T> ) { return type_kind::class_; }
+        if constexpr ( enum_kind<T> ) { return type_kind::enum_; }
+        if constexpr ( function_kind<T> ) { return type_kind::function_; }
+        if constexpr ( member_kind<T> ) { return type_kind::member_; }
+        if constexpr ( method_kind<T> ) { return type_kind::method_; }
+        if constexpr ( number_kind<T> ) { return type_kind::number_; }
+        if constexpr ( pointer_kind<T> ) { return type_kind::pointer_; }
+        if constexpr ( reference_kind<T> ) { return type_kind::reference_; }
+        if constexpr ( void_kind<T> ) { return type_kind::void_; }
+    }
+}
+
+namespace meta_hpp::detail
+{
+    template < type_kind Kind >
+    struct type_kind_traits;
+
+    template <>
+    struct type_kind_traits<type_kind::array_> {
+        using kind_type = array_type;
+        using kind_type_data = array_type_data;
+    };
+
+    template <>
+    struct type_kind_traits<type_kind::class_> {
+        using kind_type = class_type;
+        using kind_type_data = class_type_data;
+    };
+
+    template <>
+    struct type_kind_traits<type_kind::ctor_> {
+        using kind_type = ctor_type;
+        using kind_type_data = ctor_type_data;
+    };
+
+    template <>
+    struct type_kind_traits<type_kind::enum_> {
+        using kind_type = enum_type;
+        using kind_type_data = enum_type_data;
+    };
+
+    template <>
+    struct type_kind_traits<type_kind::function_> {
+        using kind_type = function_type;
+        using kind_type_data = function_type_data;
+    };
+
+    template <>
+    struct type_kind_traits<type_kind::member_> {
+        using kind_type = member_type;
+        using kind_type_data = member_type_data;
+    };
+
+    template <>
+    struct type_kind_traits<type_kind::method_> {
+        using kind_type = method_type;
+        using kind_type_data = method_type_data;
+    };
+
+    template <>
+    struct type_kind_traits<type_kind::number_> {
+        using kind_type = number_type;
+        using kind_type_data = number_type_data;
+    };
+
+    template <>
+    struct type_kind_traits<type_kind::pointer_> {
+        using kind_type = pointer_type;
+        using kind_type_data = pointer_type_data;
+    };
+
+    template <>
+    struct type_kind_traits<type_kind::reference_> {
+        using kind_type = reference_type;
+        using kind_type_data = reference_type_data;
+    };
+
+    template <>
+    struct type_kind_traits<type_kind::void_> {
+        using kind_type = void_type;
+        using kind_type_data = void_type_data;
+    };
+
+    template < typename T >
+    using kind_type = typename type_kind_traits<make_type_kind<T>()>::kind_type;
+
+    template < typename T >
+    using kind_type_data = typename type_kind_traits<make_type_kind<T>()>::kind_type_data;
+
+    template < typename T >
+    using kind_type_data_ptr = std::shared_ptr<kind_type_data<T>>;
+}
diff --git a/headers/meta.hpp/meta_traits.hpp b/headers/meta.hpp/meta_traits.hpp
new file mode 100644
index 0000000..37af24b
--- /dev/null
+++ b/headers/meta.hpp/meta_traits.hpp
@@ -0,0 +1,116 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#pragma once
+
+#include "meta_base.hpp"
+#include "meta_kinds.hpp"
+
+namespace meta_hpp::detail
+{
+    template < array_kind Array >
+    struct array_traits;
+
+    template < class_kind T >
+    struct class_traits;
+
+    template < class_kind Class, typename... Args >
+    struct ctor_traits;
+
+    template < enum_kind Enum >
+    struct enum_traits;
+
+    template < function_kind Function >
+    struct function_traits;
+
+    template < member_kind Member >
+    struct member_traits;
+
+    template < method_kind Method >
+    struct method_traits;
+
+    template < number_kind Number >
+    struct number_traits;
+
+    template < pointer_kind Pointer >
+    struct pointer_traits;
+
+    template < reference_kind Reference >
+    struct reference_traits;
+
+    template < void_kind Void >
+    struct void_traits;
+}
+
+namespace meta_hpp
+{
+    enum class array_flags : std::uint32_t {
+        is_bounded = 1 << 0,
+        is_unbounded = 1 << 1,
+    };
+
+    enum class class_flags : std::uint32_t {
+        is_empty = 1 << 1,
+        is_final = 1 << 2,
+        is_abstract = 1 << 3,
+        is_polymorphic = 1 << 4,
+        is_template_instantiation = 1 << 5,
+    };
+
+    enum class ctor_flags : std::uint32_t {
+        is_noexcept = 1 << 0,
+    };
+
+    enum class enum_flags : std::uint32_t {
+    };
+
+    enum class function_flags : std::uint32_t {
+        is_noexcept = 1 << 0,
+    };
+
+    enum class member_flags : std::uint32_t {
+    };
+
+    enum class method_flags : std::uint32_t {
+        is_const = 1 << 0,
+        is_noexcept = 1 << 1,
+        is_volatile = 1 << 2,
+        is_lvalue_qualified = 1 << 3,
+        is_rvalue_qualified = 1 << 4,
+    };
+
+    enum class number_flags : std::uint32_t {
+        is_signed = 1 << 1,
+        is_unsigned = 1 << 2,
+        is_integral = 1 << 3,
+        is_floating_point = 1 << 4,
+    };
+
+    enum class pointer_flags : std::uint32_t {
+        is_readonly = 1 << 0,
+    };
+
+    enum class reference_flags : std::uint32_t {
+        is_readonly = 1 << 0,
+        is_lvalue = 1 << 1,
+        is_rvalue = 1 << 2,
+    };
+
+    enum class void_flags : std::uint32_t {
+    };
+
+    ENUM_HPP_OPERATORS_DECL(array_flags)
+    ENUM_HPP_OPERATORS_DECL(class_flags)
+    ENUM_HPP_OPERATORS_DECL(ctor_flags)
+    ENUM_HPP_OPERATORS_DECL(enum_flags)
+    ENUM_HPP_OPERATORS_DECL(function_flags)
+    ENUM_HPP_OPERATORS_DECL(member_flags)
+    ENUM_HPP_OPERATORS_DECL(method_flags)
+    ENUM_HPP_OPERATORS_DECL(number_flags)
+    ENUM_HPP_OPERATORS_DECL(pointer_flags)
+    ENUM_HPP_OPERATORS_DECL(reference_flags)
+    ENUM_HPP_OPERATORS_DECL(void_flags)
+}
diff --git a/headers/meta.hpp/meta_traits/array_traits.hpp b/headers/meta.hpp/meta_traits/array_traits.hpp
new file mode 100644
index 0000000..e979661
--- /dev/null
+++ b/headers/meta.hpp/meta_traits/array_traits.hpp
@@ -0,0 +1,27 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#pragma once
+
+#include "../meta_base.hpp"
+#include "../meta_traits.hpp"
+
+namespace meta_hpp::detail
+{
+    template < array_kind Array >
+    struct array_traits {
+        static constexpr std::size_t extent{std::extent_v<Array>};
+
+        using data_type = std::remove_extent_t<Array>;
+
+        static bitflags<array_flags> make_flags() noexcept {
+            bitflags<array_flags> flags;
+            if ( std::is_bounded_array_v<Array> ) flags.set(array_flags::is_bounded);
+            if ( std::is_unbounded_array_v<Array> ) flags.set(array_flags::is_unbounded);
+            return flags;
+        }
+    };
+}
diff --git a/headers/meta.hpp/meta_traits/class_traits.hpp b/headers/meta.hpp/meta_traits/class_traits.hpp
new file mode 100644
index 0000000..9b06334
--- /dev/null
+++ b/headers/meta.hpp/meta_traits/class_traits.hpp
@@ -0,0 +1,60 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#pragma once
+
+#include "../meta_base.hpp"
+#include "../meta_traits.hpp"
+
+namespace meta_hpp::detail
+{
+    namespace impl
+    {
+        template < class_kind T >
+        struct class_traits_base {
+            static constexpr std::size_t arity{0};
+
+            using argument_types = type_list<>;
+
+            static bitflags<class_flags> make_flags() noexcept {
+                return {};
+            }
+
+            static std::vector<any_type> make_argument_types() {
+                return {};
+            }
+        };
+
+        template < template < typename... > typename T, typename... Args >
+        struct class_traits_base<T<Args...>> {
+            static constexpr std::size_t arity{sizeof...(Args)};
+
+            using argument_types = type_list<Args...>;
+
+            static bitflags<class_flags> make_flags() noexcept {
+                return class_flags::is_template_instantiation;
+            }
+
+            static std::vector<any_type> make_argument_types() {
+                return { resolve_type<Args>()... };
+            }
+        };
+    }
+
+    template < class_kind T >
+    struct class_traits : impl::class_traits_base<T> {
+        static constexpr std::size_t size{sizeof(T)};
+
+        static bitflags<class_flags> make_flags() noexcept {
+            bitflags<class_flags> flags;
+            if constexpr ( std::is_empty_v<T> ) flags.set(class_flags::is_empty);
+            if constexpr ( std::is_final_v<T> ) flags.set(class_flags::is_final);
+            if constexpr ( std::is_abstract_v<T> ) flags.set(class_flags::is_abstract);
+            if constexpr ( std::is_polymorphic_v<T> ) flags.set(class_flags::is_polymorphic);
+            return flags | impl::class_traits_base<T>::make_flags();
+        }
+    };
+}
diff --git a/headers/meta.hpp/meta_traits/ctor_traits.hpp b/headers/meta.hpp/meta_traits/ctor_traits.hpp
new file mode 100644
index 0000000..745f1e0
--- /dev/null
+++ b/headers/meta.hpp/meta_traits/ctor_traits.hpp
@@ -0,0 +1,31 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#pragma once
+
+#include "../meta_base.hpp"
+#include "../meta_traits.hpp"
+
+namespace meta_hpp::detail
+{
+    template < class_kind Class, typename... Args >
+    struct ctor_traits {
+        static constexpr std::size_t arity{sizeof...(Args)};
+
+        using class_type = Class;
+        using argument_types = type_list<Args...>;
+
+        static bitflags<ctor_flags> make_flags() noexcept {
+            bitflags<ctor_flags> flags;
+            if constexpr ( std::is_nothrow_constructible_v<Class, Args...> ) flags.set(ctor_flags::is_noexcept);
+            return flags;
+        }
+
+        static std::vector<any_type> make_argument_types() {
+            return { resolve_type<Args>()... };
+        }
+    };
+}
diff --git a/untests/meta_tests.cpp b/headers/meta.hpp/meta_traits/enum_traits.hpp
similarity index 54%
rename from untests/meta_tests.cpp
rename to headers/meta.hpp/meta_traits/enum_traits.hpp
index cbb5826..ba77ce3 100644
--- a/untests/meta_tests.cpp
+++ b/headers/meta.hpp/meta_traits/enum_traits.hpp
@@ -4,11 +4,19 @@
  * Copyright (C) 2021, by Matvey Cherevko (blackmatov@gmail.com)
  ******************************************************************************/
 
-#include "meta_tests.hpp"
+#pragma once
 
-namespace
+#include "../meta_base.hpp"
+#include "../meta_traits.hpp"
+
+namespace meta_hpp::detail
 {
-}
+    template < enum_kind Enum >
+    struct enum_traits {
+        using underlying_type = std::underlying_type_t<Enum>;
 
-TEST_CASE("meta") {
+        static bitflags<enum_flags> make_flags() noexcept {
+            return {};
+        }
+    };
 }
diff --git a/headers/meta.hpp/meta_traits/function_traits.hpp b/headers/meta.hpp/meta_traits/function_traits.hpp
new file mode 100644
index 0000000..709e6a7
--- /dev/null
+++ b/headers/meta.hpp/meta_traits/function_traits.hpp
@@ -0,0 +1,39 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#pragma once
+
+#include "../meta_base.hpp"
+#include "../meta_traits.hpp"
+
+namespace meta_hpp::detail
+{
+    template < function_kind Function >
+    struct function_traits;
+
+    template < typename R, typename... Args >
+    struct function_traits<R(*)(Args...)> {
+        static constexpr std::size_t arity{sizeof...(Args)};
+
+        using return_type = R;
+        using argument_types = type_list<Args...>;
+
+        static bitflags<function_flags> make_flags() noexcept {
+            return {};
+        }
+
+        static std::vector<any_type> make_argument_types() {
+            return { resolve_type<Args>()... };
+        }
+    };
+
+    template < typename R, typename... Args >
+    struct function_traits<R(*)(Args...) noexcept> : function_traits<R(*)(Args...)> {
+        static bitflags<function_flags> make_flags() noexcept {
+            return function_flags::is_noexcept;
+        }
+    };
+}
diff --git a/headers/meta.hpp/meta_traits/member_traits.hpp b/headers/meta.hpp/meta_traits/member_traits.hpp
new file mode 100644
index 0000000..0500082
--- /dev/null
+++ b/headers/meta.hpp/meta_traits/member_traits.hpp
@@ -0,0 +1,26 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#pragma once
+
+#include "../meta_base.hpp"
+#include "../meta_traits.hpp"
+
+namespace meta_hpp::detail
+{
+    template < member_kind Member >
+    struct member_traits;
+
+    template < typename V, typename C >
+    struct member_traits<V C::*> {
+        using class_type = C;
+        using value_type = V;
+
+        static bitflags<member_flags> make_flags() noexcept {
+            return {};
+        }
+    };
+}
diff --git a/headers/meta.hpp/meta_traits/method_traits.hpp b/headers/meta.hpp/meta_traits/method_traits.hpp
new file mode 100644
index 0000000..fef9086
--- /dev/null
+++ b/headers/meta.hpp/meta_traits/method_traits.hpp
@@ -0,0 +1,220 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#pragma once
+
+#include "../meta_base.hpp"
+#include "../meta_traits.hpp"
+
+namespace meta_hpp::detail
+{
+    template < method_kind Method >
+    struct method_traits;
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...)> {
+        static constexpr std::size_t arity{sizeof...(Args)};
+
+        using class_type = C;
+        using return_type = R;
+        using qualified_type = C;
+        using argument_types = type_list<Args...>;
+
+        static bitflags<method_flags> make_flags() noexcept {
+            return {};
+        }
+
+        static std::vector<any_type> make_argument_types() {
+            return { resolve_type<Args>()... };
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) const> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = const C;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_const;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) noexcept> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = C;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_noexcept;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) const noexcept> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = const C;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_const | method_flags::is_noexcept;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) &> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = C&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_lvalue_qualified;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) & noexcept> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = C&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_noexcept | method_flags::is_lvalue_qualified;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) const &> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = const C&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_const | method_flags::is_lvalue_qualified;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) const & noexcept> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = const C&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_const | method_flags::is_noexcept | method_flags::is_lvalue_qualified;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) &&> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = C&&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_rvalue_qualified;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) && noexcept> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = C&&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_noexcept | method_flags::is_rvalue_qualified;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) const &&> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = const C&&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_const | method_flags::is_rvalue_qualified;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) const && noexcept> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = const C&&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_const | method_flags::is_noexcept | method_flags::is_rvalue_qualified;
+        }
+    };
+
+    //
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) volatile> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = C;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_volatile;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) volatile const> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = const C;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_volatile | method_flags::is_const;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) volatile noexcept> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = C;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_volatile | method_flags::is_noexcept;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) volatile const noexcept> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = const C;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_volatile | method_flags::is_const | method_flags::is_noexcept;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) volatile &> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = C&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_volatile | method_flags::is_lvalue_qualified;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) volatile & noexcept> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = C&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_volatile | method_flags::is_noexcept | method_flags::is_lvalue_qualified;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) volatile const &> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = const C&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_volatile | method_flags::is_const | method_flags::is_lvalue_qualified;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) volatile const & noexcept> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = const C&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_volatile | method_flags::is_const | method_flags::is_noexcept | method_flags::is_lvalue_qualified;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) volatile &&> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = C&&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_volatile | method_flags::is_rvalue_qualified;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) volatile && noexcept> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = C&&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_volatile | method_flags::is_noexcept | method_flags::is_rvalue_qualified;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) volatile const &&> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = const C&&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_volatile | method_flags::is_const | method_flags::is_rvalue_qualified;
+        }
+    };
+
+    template < typename R, typename C, typename... Args >
+    struct method_traits<R(C::*)(Args...) volatile const && noexcept> : method_traits<R(C::*)(Args...)> {
+        using qualified_type = const C&&;
+        static bitflags<method_flags> make_flags() noexcept {
+            return method_flags::is_volatile | method_flags::is_const | method_flags::is_noexcept | method_flags::is_rvalue_qualified;
+        }
+    };
+}
diff --git a/headers/meta.hpp/meta_traits/number_traits.hpp b/headers/meta.hpp/meta_traits/number_traits.hpp
new file mode 100644
index 0000000..eb69abc
--- /dev/null
+++ b/headers/meta.hpp/meta_traits/number_traits.hpp
@@ -0,0 +1,27 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#pragma once
+
+#include "../meta_base.hpp"
+#include "../meta_traits.hpp"
+
+namespace meta_hpp::detail
+{
+    template < number_kind Number >
+    struct number_traits {
+        static constexpr std::size_t size{sizeof(Number)};
+
+        static bitflags<number_flags> make_flags() noexcept {
+            bitflags<number_flags> flags;
+            if ( std::is_signed_v<Number> ) flags.set(number_flags::is_signed);
+            if ( std::is_unsigned_v<Number> ) flags.set(number_flags::is_unsigned);
+            if ( std::is_integral_v<Number> ) flags.set(number_flags::is_integral);
+            if ( std::is_floating_point_v<Number> ) flags.set(number_flags::is_floating_point);
+            return flags;
+        }
+    };
+}
diff --git a/headers/meta.hpp/meta_traits/pointer_traits.hpp b/headers/meta.hpp/meta_traits/pointer_traits.hpp
new file mode 100644
index 0000000..5b66ea3
--- /dev/null
+++ b/headers/meta.hpp/meta_traits/pointer_traits.hpp
@@ -0,0 +1,24 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#pragma once
+
+#include "../meta_base.hpp"
+#include "../meta_traits.hpp"
+
+namespace meta_hpp::detail
+{
+    template < pointer_kind Pointer >
+    struct pointer_traits {
+        using data_type = std::remove_pointer_t<Pointer>;
+
+        static bitflags<pointer_flags> make_flags() noexcept {
+            bitflags<pointer_flags> flags;
+            if constexpr ( std::is_const_v<data_type> ) flags.set(pointer_flags::is_readonly);
+            return flags;
+        }
+    };
+}
diff --git a/headers/meta.hpp/meta_traits/reference_traits.hpp b/headers/meta.hpp/meta_traits/reference_traits.hpp
new file mode 100644
index 0000000..4eef018
--- /dev/null
+++ b/headers/meta.hpp/meta_traits/reference_traits.hpp
@@ -0,0 +1,26 @@
+/*******************************************************************************
+ * This file is part of the "https://github.com/blackmatov/meta.hpp"
+ * For conditions of distribution and use, see copyright notice in LICENSE.md
+ * Copyright (C) 2021, by Matvey Cherevko (blackmatov@gmail.com)
+ ******************************************************************************/
+
+#pragma once
+
+#include "../meta_base.hpp"
+#include "../meta_traits.hpp"
+
+namespace meta_hpp::detail
+{
+    template < reference_kind Reference >
+    struct reference_traits {
+        using data_type = std::remove_reference_t<Reference>;
+
+        static bitflags<reference_flags> make_flags() noexcept {
+            bitflags<reference_flags> flags;
+            if constexpr ( std::is_const_v<data_type> ) flags.set(reference_flags::is_readonly);
+            if constexpr ( std::is_lvalue_reference_v<Reference> ) flags.set(reference_flags::is_lvalue);
+            if constexpr ( std::is_rvalue_reference_v<Reference> ) flags.set(reference_flags::is_rvalue);
+            return flags;
+        }
+    };
+}
diff --git a/headers/meta.hpp/meta_fwd.hpp b/headers/meta.hpp/meta_traits/void_traits.hpp
similarity index 61%
rename from headers/meta.hpp/meta_fwd.hpp
rename to headers/meta.hpp/meta_traits/void_traits.hpp
index bae8590..f3ced24 100644
--- a/headers/meta.hpp/meta_fwd.hpp
+++ b/headers/meta.hpp/meta_traits/void_traits.hpp
@@ -6,6 +6,15 @@
 
 #pragma once
 
-namespace meta_hpp
+#include "../meta_base.hpp"
+#include "../meta_traits.hpp"
+
+namespace meta_hpp::detail
 {
+    template < void_kind Void >
+    struct void_traits {
+        static bitflags<void_flags> make_flags() noexcept {
+            return {};
+        }
+    };
 }