diff --git a/include/boost/callable_traits/detail/config.hpp b/include/boost/callable_traits/detail/config.hpp
index 6b3d2ea..fd64212 100644
--- a/include/boost/callable_traits/detail/config.hpp
+++ b/include/boost/callable_traits/detail/config.hpp
@@ -65,8 +65,6 @@ Distributed under the Boost Software License, Version 1.0.
 #  endif // #if !defined( __clang__ )
 #endif // #ifdef _MSC_VER
 
-#define BOOST_CLBL_TRTS_IX_SEQ(...) ::std::index_sequence< __VA_ARGS__ >
-#define BOOST_CLBL_TRTS_MAKE_IX_SEQ(...) ::std::make_index_sequence< __VA_ARGS__ >
 #define BOOST_CLBL_TRTS_DISJUNCTION(...) ::std::disjunction< __VA_ARGS__ >
 
 #ifndef __cpp_variable_templates
@@ -77,10 +75,6 @@ Distributed under the Boost Software License, Version 1.0.
 #  include <boost/callable_traits/detail/polyfills/disjunction.hpp>
 #endif //__cpp_lib_logical_traits
 
-#ifndef __cpp_lib_integer_sequence
-#  include <boost/callable_traits/detail/polyfills/make_index_sequence.hpp>
-#endif // __cpp_lib_integer_sequence
-
 #if defined(BOOST_CLBL_TRTS_MSVC) && !defined(BOOST_DISABLE_WIN32)
 #  define BOOST_CLBL_TRTS_DEFAULT_VARARGS_CC __cdecl
 #  define BOOST_CLBL_TRTS_PMF_VARGARGS_CDECL_DEFAULT
diff --git a/include/boost/callable_traits/detail/polyfills/make_index_sequence.hpp b/include/boost/callable_traits/detail/polyfills/make_index_sequence.hpp
deleted file mode 100644
index a4a6e82..0000000
--- a/include/boost/callable_traits/detail/polyfills/make_index_sequence.hpp
+++ /dev/null
@@ -1,50 +0,0 @@
-/*
-Copyright Barrett Adair 2016-2017
-
-Distributed under the Boost Software License, Version 1.0.
-(See accompanying file LICENSE.md or copy at http://boost.org/LICENSE_1_0.txt)
-*/
-
-#ifndef BOOST_CLBL_TRTS_DETAIL_POLYFILLS_MAKE_INDEX_SEQUENCE_HPP
-#define BOOST_CLBL_TRTS_DETAIL_POLYFILLS_MAKE_INDEX_SEQUENCE_HPP
-
-#undef BOOST_CLBL_TRTS_IX_SEQ
-#define BOOST_CLBL_TRTS_IX_SEQ(...) \
-    ::boost::callable_traits::detail::index_sequence<__VA_ARGS__>
-
-#undef BOOST_CLBL_TRTS_MAKE_IX_SEQ
-#define BOOST_CLBL_TRTS_MAKE_IX_SEQ(...) \
-    ::boost::callable_traits::detail::make_index_sequence<__VA_ARGS__>
-
-namespace boost { namespace callable_traits { namespace detail { 
-
-template<std::size_t...>
-struct index_sequence { using type = index_sequence; };
-
-template<typename, typename>
-struct concat;
-
-template<std::size_t... I1, std::size_t... I2>
-struct concat<index_sequence<I1...>, index_sequence<I2...>>
-    : index_sequence<I1..., (sizeof...(I1)+I2)...> {};
-
-template<std::size_t N>
-    struct make_index_sequence_t;
-
-template<std::size_t N>
-struct make_index_sequence_t : concat< 
-    typename make_index_sequence_t<N/2>::type,
-    typename make_index_sequence_t<N - N/2>::type >::type {};
-
-template<>
-struct make_index_sequence_t<0> : index_sequence<> {};
-
-template<>
-struct make_index_sequence_t<1> : index_sequence<0> {};
-
-template<std::size_t... I>
-using make_index_sequence = typename make_index_sequence_t<I...>::type;
-
-}}} // namespace boost::callable_traits::detail
-
-#endif // #ifndef BOOST_CLBL_TRTS_DETAIL_POLYFILLS_MAKE_INDEX_SEQUENCE_HPP