anchor.diff:      ProxyStrategy = decode_proxy_strategy(get_element(<<"proxy-strategy">>,
                                                         KVs)),
       RestApiPrefix = binary_to_list(get_element(<<"rest-api-prefix">>, KVs)),
  +    %% DocRoot has to be a list in order for mochiweb to be able to guess
  +    %% the MIME type.
  +    DocRoot = binary_to_list(get_element(<<"doc-root">>, KVs)),
       case {valid_service(ServiceName),
             find_plugin_by_prefix(RestApiPrefix, Plugins)} of
           {true, false} ->
  
positive.code: -record(plugin, { name            :: service_name(),
                    proxy_strategy  :: proxy_strategy(),
                    rest_api_prefix :: rest_api_prefix(),
                    doc_root        :: binary()}).
  -type plugin()  :: #plugin{}.
  -type plugins() :: [plugin()].
  
  
negative.code: %%%
  maybe_serve_file(RestPrefix, Plugins, Req, Path) ->
      case doc_root(RestPrefix, Plugins) of
          DocRoot when is_list(DocRoot) ->
              menelaus_util:serve_file(Req,
                                       Path,
                                       DocRoot,
  