diff --git a/include/mapnik/json/feature_generator_grammar.hpp b/include/mapnik/json/feature_generator_grammar.hpp
index 7bfbbc5e2..5df0cf938 100644
--- a/include/mapnik/json/feature_generator_grammar.hpp
+++ b/include/mapnik/json/feature_generator_grammar.hpp
@@ -30,88 +30,86 @@
 #include <mapnik/json/properties_generator_grammar.hpp>
 
 // boost
+#include <boost/spirit/home/support/attributes.hpp>
 #include <boost/spirit/include/karma.hpp>
+#include <boost/fusion/include/adapt_adt.hpp>
+#include <boost/spirit/include/support_adapt_adt_attributes.hpp>
+
+namespace mapnik {
+
+struct kv_store
+{
+    using value_type = mapnik::feature_impl::value_type;
+    using iterator_type = mapnik::feature_kv_iterator2;
+    kv_store(mapnik::feature_impl const& f)
+        : start_(mapnik::value_not_null(),f.begin(),f.end()),
+          end_(mapnik::value_not_null(),f.end(),f.end())
+    {}
+    iterator_type start_;
+    iterator_type end_;
+};
+
+}
 
 namespace boost { namespace spirit { namespace traits {
 
 template <>
-struct is_container<mapnik::feature_impl const> : mpl::false_ {} ;
+struct is_container<mapnik::kv_store const> : mpl::false_ {} ;
 
 template <>
-struct container_iterator<mapnik::feature_impl const>
+struct container_iterator<mapnik::kv_store const>
 {
-    using type = mapnik::feature_kv_iterator2;
+    using type = mapnik::kv_store::iterator_type;
 };
 
 template <>
-struct begin_container<mapnik::feature_impl const>
+struct begin_container<mapnik::kv_store const>
 {
-    static mapnik::feature_kv_iterator2
-    call (mapnik::feature_impl const& f)
+    static mapnik::kv_store::iterator_type
+    call (mapnik::kv_store const& kv)
     {
-        return mapnik::feature_kv_iterator2(mapnik::value_not_null(),f.begin(),f.end());
+        return kv.start_;
     }
 };
 
 template <>
-struct end_container<mapnik::feature_impl const>
+struct end_container<mapnik::kv_store const>
 {
-    static mapnik::feature_kv_iterator2
-    call (mapnik::feature_impl const& f)
+    static mapnik::kv_store::iterator_type
+    call (mapnik::kv_store const& kv)
     {
-        return mapnik::feature_kv_iterator2(mapnik::value_not_null(),f.end(),f.end());
+        return kv.end_;
     }
 };
 
-#if BOOST_VERSION >= 106900
-template <>
-struct transform_attribute<const mapnik::feature_impl, const mapnik::feature_impl &, boost::spirit::karma::domain, void>
-    : detail::transform_attribute_base<mapnik::feature_impl const, mapnik::feature_impl const&,  boost::spirit::karma::domain>
-{};
-
-template <>
-struct transform_attribute<const boost::fusion::cons<const mapnik::feature_impl &, boost::fusion::nil_>, const mapnik::feature_impl &,
-      boost::spirit::karma::domain, void>
-    : detail::transform_attribute_base<const boost::fusion::cons<const mapnik::feature_impl &, boost::fusion::nil_>, mapnik::feature_impl const&,  boost::spirit::karma::domain>
-{};
-#endif
 }}}
 
+BOOST_FUSION_ADAPT_ADT(
+    mapnik::feature_impl,
+    (int, int, obj.id(), /**/)
+    (mapnik::geometry::geometry<double>const&, mapnik::geometry::geometry<double> const&, obj.get_geometry(),/**/)
+    (mapnik::kv_store const, mapnik::kv_store const, mapnik::kv_store(obj), /**/))
+
 namespace mapnik { namespace json {
+namespace detail {
+template <typename T>
+#if BOOST_VERSION >= 107000
+struct attribute_type { using type = T();};
+#else
+struct attribute_type { using type = T const&();};
+#endif
+}
 
 namespace karma = boost::spirit::karma;
 
-template <typename T>
-struct get_id
-{
-    using feature_type = T;
-    using result_type = mapnik::value_integer;
-    result_type operator() (feature_type const& f) const
-    {
-        return f.id();
-    }
-};
-
-struct extract_geometry
-{
-    using result_type = mapnik::geometry::geometry<double> const&;
-    template <typename T>
-    result_type operator() (T const& f) const
-    {
-        return f.get_geometry();
-    }
-};
-
 template <typename OutputIterator, typename FeatureType>
 struct feature_generator_grammar :
-        karma::grammar<OutputIterator, FeatureType const&()>
+        karma::grammar<OutputIterator, typename detail::attribute_type<FeatureType>::type>
 {
     feature_generator_grammar();
-    karma::rule<OutputIterator, FeatureType const&()> feature;
-    geometry_generator_grammar<OutputIterator, mapnik::geometry::geometry<double> > geometry;
-    properties_generator_grammar<OutputIterator, FeatureType> properties;
-    boost::phoenix::function<get_id<FeatureType> > id_;
-    boost::phoenix::function<extract_geometry> geom_;
+    karma::rule<OutputIterator, typename detail::attribute_type<FeatureType>::type> feature;
+    geometry_generator_grammar<OutputIterator, mapnik::geometry::geometry<double>> geometry;
+    properties_generator_grammar<OutputIterator, mapnik::kv_store> properties;
 };
 
 }}
diff --git a/include/mapnik/json/feature_generator_grammar_impl.hpp b/include/mapnik/json/feature_generator_grammar_impl.hpp
index baf4be853..fd65e7320 100644
--- a/include/mapnik/json/feature_generator_grammar_impl.hpp
+++ b/include/mapnik/json/feature_generator_grammar_impl.hpp
@@ -29,13 +29,11 @@ feature_generator_grammar<OutputIterator, FeatureType>::feature_generator_gramma
   : feature_generator_grammar::base_type(feature)
 {
     boost::spirit::karma::lit_type lit;
-    boost::spirit::karma::uint_type uint_;
-    boost::spirit::karma::_val_type _val;
-    boost::spirit::karma::_1_type _1;
+    boost::spirit::karma::int_type int_;
 
-    feature = lit("{\"type\":\"Feature\",\"id\":")
-        << uint_[_1 = id_(_val)]
-        << lit(",\"geometry\":") << geometry[_1 = geom_(_val)]
+    feature  = lit("{\"type\":\"Feature\"")
+        << lit(",\"id\":") << int_
+        << lit(",\"geometry\":") << geometry
         << lit(",\"properties\":") << properties
         << lit('}')
         ;
diff --git a/include/mapnik/json/properties_generator_grammar.hpp b/include/mapnik/json/properties_generator_grammar.hpp
index 93dfaef75..2788ee06a 100644
--- a/include/mapnik/json/properties_generator_grammar.hpp
+++ b/include/mapnik/json/properties_generator_grammar.hpp
@@ -30,6 +30,7 @@
 #include <mapnik/warning_ignore.hpp>
 #include <boost/spirit/include/karma.hpp>
 #include <boost/spirit/include/phoenix_function.hpp>
+#include <boost/spirit/home/karma/domain.hpp>
 #pragma GCC diagnostic pop
 
 #include <string>
@@ -50,7 +51,7 @@ struct escaped_string
 
 struct extract_string
 {
-    using result_type = std::tuple<std::string,bool>;
+    using result_type = std::tuple<std::string, bool>;
 
     result_type operator() (mapnik::value const& val) const
     {
@@ -61,18 +62,16 @@ struct extract_string
 
 template <typename OutputIterator, typename KeyValueStore>
 struct properties_generator_grammar
-    : karma::grammar<OutputIterator, KeyValueStore const&()>
+    : karma::grammar<OutputIterator, KeyValueStore()>
 {
     using pair_type = std::tuple<std::string, mapnik::value>;
     properties_generator_grammar();
     // rules
-    karma::rule<OutputIterator, KeyValueStore const&()> properties;
+    karma::rule<OutputIterator, KeyValueStore()> properties;
     karma::rule<OutputIterator, pair_type()> pair;
     karma::rule<OutputIterator, std::tuple<std::string,bool>()> value;
-    karma::rule<OutputIterator, mapnik::value_null()> value_null_;
-    karma::rule<OutputIterator, mapnik::value_unicode_string()> ustring;
+    //
     escaped_string<OutputIterator> escaped_string_;
-    typename karma::int_generator<mapnik::value_integer,10, false> int__;
     boost::phoenix::function<extract_string> extract_string_;
     std::string quote_;
 };
diff --git a/include/mapnik/json/properties_generator_grammar_impl.hpp b/include/mapnik/json/properties_generator_grammar_impl.hpp
index b6d4a7527..ca4ca4453 100644
--- a/include/mapnik/json/properties_generator_grammar_impl.hpp
+++ b/include/mapnik/json/properties_generator_grammar_impl.hpp
@@ -69,6 +69,7 @@ properties_generator_grammar<OutputIterator, KeyValueStore>::properties_generato
     boost::spirit::karma::string_type kstring;
     boost::spirit::karma::eps_type eps;
     using boost::phoenix::at_c;
+
     properties = lit('{')
         << -(pair % lit(','))
         << lit('}')
@@ -84,7 +85,6 @@ properties_generator_grammar<OutputIterator, KeyValueStore>::properties_generato
         |
         kstring[_1 = at_c<0>(_val)]
         ;
-
 }
 
 }}
diff --git a/include/mapnik/util/spirit_transform_attribute.hpp b/include/mapnik/util/spirit_transform_attribute.hpp
deleted file mode 100644
index 1666089ce..000000000
--- a/include/mapnik/util/spirit_transform_attribute.hpp
+++ /dev/null
@@ -1,216 +0,0 @@
-/*****************************************************************************
- *
- * This file is part of Mapnik (c++ mapping toolkit)
- *
- * Copyright (C) 2017 Artem Pavlenko
- *
- * This library is free software; you can redistribute it and/or
- * modify it under the terms of the GNU Lesser General Public
- * License as published by the Free Software Foundation; either
- * version 2.1 of the License, or (at your option) any later version.
- *
- * This library is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
- * Lesser General Public License for more details.
- *
- * You should have received a copy of the GNU Lesser General Public
- * License along with this library; if not, write to the Free Software
- * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA
- *
- *****************************************************************************/
-
-#ifndef MAPNIK_UTIL_SPIRIT_TRANSFORM_ATTRIBUTE_HPP
-#define MAPNIK_UTIL_SPIRIT_TRANSFORM_ATTRIBUTE_HPP
-
-#include <mapnik/geometry.hpp>
-#include <mapnik/util/variant.hpp>
-
-#include <cstdint>
-
-#pragma GCC diagnostic push
-#include <mapnik/warning_ignore.hpp>
-#include <boost/spirit/include/karma.hpp>
-#pragma GCC diagnostic pop
-
-namespace boost { namespace spirit { namespace traits {
-
-    template <>
-    struct transform_attribute<mapnik::geometry::geometry<double> const,
-                               mapnik::geometry::point<double> const&, karma::domain>
-    {
-        using type = mapnik::geometry::point<double> const&;
-        static type pre(mapnik::geometry::geometry<double> const& geom)
-        {
-            return mapnik::util::get<mapnik::geometry::point<double> >(geom);
-        }
-    };
-
-    template <>
-    struct transform_attribute<mapnik::geometry::geometry<double> const,
-                               mapnik::geometry::line_string<double> const&, karma::domain>
-    {
-        using type = mapnik::geometry::line_string<double> const&;
-        static type pre(mapnik::geometry::geometry<double> const& geom)
-        {
-            return mapnik::util::get<mapnik::geometry::line_string<double> >(geom);
-        }
-    };
-
-    template <>
-    struct transform_attribute<mapnik::geometry::geometry<double> const,
-                               mapnik::geometry::polygon<double> const&, karma::domain>
-    {
-        using type = mapnik::geometry::polygon<double> const&;
-        static type pre(mapnik::geometry::geometry<double> const& geom)
-        {
-            return mapnik::util::get<mapnik::geometry::polygon<double> >(geom);
-        }
-    };
-
-//template <>
-//  struct transform_attribute<mapnik::geometry::polygon<double> const,
-//                             mapnik::geometry::polygon<double>::rings_container const&, karma::domain>
-//  {
-//      using type = mapnik::geometry::polygon<double>::rings_container const&;
-//      static type pre(mapnik::geometry::polygon<double> const& poly)
-//      {
-//          return poly.interior_rings;
-//      }
-//  };
-
-    template <>
-    struct transform_attribute<mapnik::geometry::geometry<double> const,
-                               mapnik::geometry::multi_point<double> const&, karma::domain>
-    {
-        using type = mapnik::geometry::multi_point<double> const&;
-        static type pre(mapnik::geometry::geometry<double> const& geom)
-        {
-            return mapnik::util::get<mapnik::geometry::multi_point<double> >(geom);
-        }
-    };
-
-    template <>
-    struct transform_attribute<mapnik::geometry::geometry<double> const,
-                               mapnik::geometry::multi_line_string<double> const&, karma::domain>
-    {
-        using type = mapnik::geometry::multi_line_string<double> const&;
-        static type pre(mapnik::geometry::geometry<double> const& geom)
-        {
-            return mapnik::util::get<mapnik::geometry::multi_line_string<double> >(geom);
-        }
-    };
-
-    template <>
-    struct transform_attribute<mapnik::geometry::geometry<double> const,
-                               mapnik::geometry::multi_polygon<double> const&, karma::domain>
-    {
-        using type = mapnik::geometry::multi_polygon<double> const&;
-        static type pre(mapnik::geometry::geometry<double> const& geom)
-        {
-            return mapnik::util::get<mapnik::geometry::multi_polygon<double> >(geom);
-        }
-    };
-
-    template <>
-    struct transform_attribute<mapnik::geometry::geometry<double> const,
-                               mapnik::geometry::geometry_collection<double> const&, karma::domain>
-    {
-        using type = mapnik::geometry::geometry_collection<double> const&;
-        static type pre(mapnik::geometry::geometry<double> const& geom)
-        {
-            return mapnik::util::get<mapnik::geometry::geometry_collection<double> >(geom);
-        }
-    };
-
-    template <>
-    struct transform_attribute<mapnik::geometry::geometry<std::int64_t> const,
-                               mapnik::geometry::point<std::int64_t> const&, karma::domain>
-    {
-        using type = mapnik::geometry::point<std::int64_t> const&;
-        static type pre(mapnik::geometry::geometry<std::int64_t> const& geom)
-        {
-            return mapnik::util::get<mapnik::geometry::point<std::int64_t> >(geom);
-        }
-    };
-
-    template <>
-    struct transform_attribute<mapnik::geometry::geometry<std::int64_t> const,
-                               mapnik::geometry::line_string<std::int64_t> const&, karma::domain>
-    {
-        using type = mapnik::geometry::line_string<std::int64_t> const&;
-        static type pre(mapnik::geometry::geometry<std::int64_t> const& geom)
-        {
-            return mapnik::util::get<mapnik::geometry::line_string<std::int64_t> >(geom);
-        }
-    };
-
-    template <>
-    struct transform_attribute<mapnik::geometry::geometry<std::int64_t> const,
-                               mapnik::geometry::polygon<std::int64_t> const&, karma::domain>
-    {
-        using type = mapnik::geometry::polygon<std::int64_t> const&;
-        static type pre(mapnik::geometry::geometry<std::int64_t> const& geom)
-        {
-            return mapnik::util::get<mapnik::geometry::polygon<std::int64_t> >(geom);
-        }
-    };
-
-//template <>
-//    struct transform_attribute<mapnik::geometry::polygon<std::int64_t> const,
-//                              mapnik::geometry::polygon<std::int64_t>::rings_container const&, karma::domain>
-//   {
-//       using type = mapnik::geometry::polygon<std::int64_t>::rings_container const&;
-//       static type pre(mapnik::geometry::polygon<std::int64_t> const& poly)
-//       {
-//           return poly.interior_rings;
-//       }
-//   };
-
-    template <>
-    struct transform_attribute<mapnik::geometry::geometry<std::int64_t> const,
-                               mapnik::geometry::multi_point<std::int64_t> const&, karma::domain>
-    {
-        using type = mapnik::geometry::multi_point<std::int64_t> const&;
-        static type pre(mapnik::geometry::geometry<std::int64_t> const& geom)
-        {
-            return mapnik::util::get<mapnik::geometry::multi_point<std::int64_t> >(geom);
-        }
-    };
-
-    template <>
-    struct transform_attribute<mapnik::geometry::geometry<std::int64_t> const,
-                               mapnik::geometry::multi_line_string<std::int64_t> const&, karma::domain>
-    {
-        using type = mapnik::geometry::multi_line_string<std::int64_t> const&;
-        static type pre(mapnik::geometry::geometry<std::int64_t> const& geom)
-        {
-            return mapnik::util::get<mapnik::geometry::multi_line_string<std::int64_t> >(geom);
-        }
-    };
-
-    template <>
-    struct transform_attribute<mapnik::geometry::geometry<std::int64_t> const,
-                               mapnik::geometry::multi_polygon<std::int64_t> const&, karma::domain>
-    {
-        using type = mapnik::geometry::multi_polygon<std::int64_t> const&;
-        static type pre(mapnik::geometry::geometry<std::int64_t> const& geom)
-        {
-            return mapnik::util::get<mapnik::geometry::multi_polygon<std::int64_t> >(geom);
-        }
-    };
-
-    template <>
-    struct transform_attribute<mapnik::geometry::geometry<std::int64_t> const,
-                               mapnik::geometry::geometry_collection<std::int64_t> const&, karma::domain>
-    {
-        using type = mapnik::geometry::geometry_collection<std::int64_t> const&;
-        static type pre(mapnik::geometry::geometry<std::int64_t> const& geom)
-        {
-            return mapnik::util::get<mapnik::geometry::geometry_collection<std::int64_t> >(geom);
-        }
-    };
-
-}}}
-
-#endif // MAPNIK_UTIL_SPIRIT_TRANSFORM_ATTRIBUTE_HPP
diff --git a/src/json/mapnik_feature_to_geojson.cpp b/src/json/mapnik_feature_to_geojson.cpp
index aca308c54..e102b65ee 100644
--- a/src/json/mapnik_feature_to_geojson.cpp
+++ b/src/json/mapnik_feature_to_geojson.cpp
@@ -32,7 +32,7 @@ namespace mapnik { namespace util {
 bool to_geojson(std::string & json, mapnik::feature_impl const& feature)
 {
     using sink_type = std::back_insert_iterator<std::string>;
-    static const mapnik::json::feature_generator_grammar<sink_type, mapnik::feature_impl> grammar;
+    static mapnik::json::feature_generator_grammar<sink_type, mapnik::feature_impl> const grammar;
     sink_type sink(json);
     return boost::spirit::karma::generate(sink, grammar, feature);
 }
diff --git a/src/json/mapnik_json_generator_grammar.cpp b/src/json/mapnik_json_generator_grammar.cpp
index 20c3f911b..b7009351f 100644
--- a/src/json/mapnik_json_generator_grammar.cpp
+++ b/src/json/mapnik_json_generator_grammar.cpp
@@ -29,6 +29,6 @@
 
 using sink_type = std::back_insert_iterator<std::string>;
 
-template struct mapnik::json::properties_generator_grammar<sink_type, mapnik::feature_impl>;
+template struct mapnik::json::properties_generator_grammar<sink_type, mapnik::kv_store>;
 template struct mapnik::json::geometry_generator_grammar<sink_type, mapnik::geometry::geometry<double> >;
 template struct mapnik::json::feature_generator_grammar<sink_type, mapnik::feature_impl>;