anchor.diff:  
   %% Request processing functions
   
  --spec handle_get(cowboy:req(), state()) -> 
  +-spec to_json(cowboy:req(), state()) -> 
       {string() | halt, cowboy:req(), state()}.
  -handle_get(Req0, State = #state{}) ->
  +to_json(Req0, State = #state{}) ->
       {ok, Filenames} = file:list_dir("scenarios"),
       Filenames2 =
           lists:filter(
  
positive.code:     {Reply, Req0, State}.
  
  
  -spec handle_post(cowboy:req(), state()) ->
      {string() | halt | ok, cowboy:req(), state()}.
  handle_post(Req0, State = #state{
                               module_name = ModuleName,
                               module_source = ModuleSource}) ->
      ScenarioPath = "scenarios/" ++ erlang:binary_to_list(ModuleName),
  
negative.code:     Reply = jsx:encode([{compile, Result}]),
      Req1 = cowboy_req:set_resp_body(Reply, Req0),
      {true, Req1, State}.
  