anchor.diff:        authenticated(Auth, Req1, State);
       _ ->
         case cowboy_req:cookie(<<"skuapso-session">>, Req) of
  -        {Val, Req1} when Val =/= undefined ->
  +        {Val, Req1} when Val =/= undefined, Val =/= <<>> ->
  +          debug("cookie ~w", [Val]),
             authenticated({cookie, Val}, Req1, State);
           _ ->
             unauthenticated(Req, State)
  
positive.code: delete_cookie(Auth, Req) ->
    trace("deleting cookie"),
    ska_session:delete_cookie(Auth),
    cowboy_req:set_resp_cookie(<<"skuapso-session">>, <<>>, [{path, "/"}], Req).
  
negative.code: upsert_cookie(Auth, Req) ->
    trace("upserting cookie"),
    case cowboy_req:cookie(<<"skuapso-session">>, Req) of
      {Val, Req1} when Val =:= undefined; Val =:= <<>> -> set_cookie(Auth, Req1);
      {Val, Req1} ->
        ska_session:set_cookie(Auth, Val),
        trace("returning from upsert"),
  