diff --git a/include/mapnik/json/json_grammar_config.hpp b/include/mapnik/json/json_grammar_config.hpp
index 564ed796f..e875dec76 100644
--- a/include/mapnik/json/json_grammar_config.hpp
+++ b/include/mapnik/json/json_grammar_config.hpp
@@ -32,6 +32,14 @@
 
 namespace mapnik { namespace json {
 
+enum well_known_names
+{
+    type = 0,
+    geometry = 1,
+    coordinates = 2,
+    properties = 3
+};
+
 struct keys_tag;
 
 namespace grammar {