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diff --git a/boost/hana/ext/std/integer_sequence.hpp b/boost/hana/ext/std/integer_sequence.hpp
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+++ b/boost/hana/ext/std/integer_sequence.hpp
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+/*!
+@file
+Adapts `std::integer_sequence` for use with Hana.
+
+@copyright Louis Dionne 2013-2016
+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_HANA_EXT_STD_INTEGER_SEQUENCE_HPP
+#define BOOST_HANA_EXT_STD_INTEGER_SEQUENCE_HPP
+
+#include <boost/hana/bool.hpp>
+#include <boost/hana/config.hpp>
+#include <boost/hana/detail/fast_and.hpp>
+#include <boost/hana/ext/std/integral_constant.hpp>
+#include <boost/hana/fwd/at.hpp>
+#include <boost/hana/fwd/core/tag_of.hpp>
+#include <boost/hana/fwd/drop_front.hpp>
+#include <boost/hana/fwd/equal.hpp>
+#include <boost/hana/fwd/is_empty.hpp>
+#include <boost/hana/fwd/unpack.hpp>
+
+#include <cstddef>
+#include <type_traits>
+#include <utility>
+
+
+#ifdef BOOST_HANA_DOXYGEN_INVOKED
+namespace std {
+    //! @ingroup group-ext-std
+    //! Adaptation of `std::integer_sequence` for Hana.
+    //!
+    //!
+    //!
+    //! Modeled concepts
+    //! ----------------
+    //! 1. `Comparable`\n
+    //! Two `std::integer_sequence`s are equal if and only if they have the
+    //! same number of elements, and if corresponding elements compare equal.
+    //! The types of the elements held in both `integer_sequence`s may be
+    //! different, as long as they can be compared.
+    //! @include example/ext/std/integer_sequence/comparable.cpp
+    //!
+    //! 2. `Foldable`\n
+    //! Folding an `integer_sequence` is equivalent to folding a sequence of
+    //! `std::integral_constant`s with the corresponding types.
+    //! @include example/ext/std/integer_sequence/foldable.cpp
+    //!
+    //! 3. `Iterable`\n
+    //! Iterating over an `integer_sequence` is equivalent to iterating over
+    //! a sequence of the corresponding `std::integral_constant`s.
+    //! @include example/ext/std/integer_sequence/iterable.cpp
+    //!
+    //! 4. `Searchable`\n
+    //! Searching through an `integer_sequence` is equivalent to searching
+    //! through the corresponding sequence of `std::integral_constant`s.
+    //! @include example/ext/std/integer_sequence/searchable.cpp
+    template <typename T, T ...v>
+    struct integer_sequence { };
+}
+#endif
+
+
+BOOST_HANA_NAMESPACE_BEGIN
+    namespace ext { namespace std { struct integer_sequence_tag; }}
+
+    template <typename T, T ...v>
+    struct tag_of<std::integer_sequence<T, v...>> {
+        using type = ext::std::integer_sequence_tag;
+    };
+
+    //////////////////////////////////////////////////////////////////////////
+    // Comparable
+    //////////////////////////////////////////////////////////////////////////
+    template <>
+    struct equal_impl<ext::std::integer_sequence_tag, ext::std::integer_sequence_tag> {
+        template <typename X, X ...xs, typename Y, Y ...ys>
+        static constexpr hana::bool_<detail::fast_and<(xs == ys)...>::value>
+        apply(std::integer_sequence<X, xs...> const&, std::integer_sequence<Y, ys...> const&)
+        { return {}; }
+
+        template <typename Xs, typename Ys>
+        static constexpr hana::false_ apply(Xs const&, Ys const&, ...)
+        { return {}; }
+    };
+
+    //////////////////////////////////////////////////////////////////////////
+    // Foldable
+    //////////////////////////////////////////////////////////////////////////
+    template <>
+    struct unpack_impl<ext::std::integer_sequence_tag> {
+        template <typename T, T ...v, typename F>
+        static constexpr decltype(auto)
+        apply(std::integer_sequence<T, v...> const&, F&& f) {
+            return static_cast<F&&>(f)(std::integral_constant<T, v>{}...);
+        }
+    };
+
+    //////////////////////////////////////////////////////////////////////////
+    // Iterable
+    //////////////////////////////////////////////////////////////////////////
+    template <>
+    struct at_impl<ext::std::integer_sequence_tag> {
+        template <typename T, T ...v, typename N>
+        static constexpr auto apply(std::integer_sequence<T, v...> const&, N const&) {
+            constexpr std::size_t n = N::value;
+            constexpr T values[] = {v...};
+            return std::integral_constant<T, values[n]>{};
+        }
+    };
+
+    template <>
+    struct drop_front_impl<ext::std::integer_sequence_tag> {
+        template <std::size_t n, typename T, T ...t, std::size_t ...i>
+        static constexpr auto drop_front_helper(std::integer_sequence<T, t...>,
+                                                std::index_sequence<i...>)
+        {
+            constexpr T ts[sizeof...(t)+1] = {t...}; // avoid 0-sized array
+            return std::integer_sequence<T, ts[n + i]...>{};
+        }
+
+        template <typename T, T ...t, typename N>
+        static constexpr auto apply(std::integer_sequence<T, t...> ts, N const&) {
+            constexpr std::size_t n = N::value;
+            constexpr std::size_t len = sizeof...(t);
+            return drop_front_helper<n>(ts,
+                    std::make_index_sequence<(n < len ? len - n : 0)>{});
+        }
+    };
+
+    template <>
+    struct is_empty_impl<ext::std::integer_sequence_tag> {
+        template <typename T, T ...xs>
+        static constexpr auto apply(std::integer_sequence<T, xs...> const&)
+        { return hana::bool_c<sizeof...(xs) == 0>; }
+    };
+BOOST_HANA_NAMESPACE_END
+
+#endif // !BOOST_HANA_EXT_STD_INTEGER_SEQUENCE_HPP