anchor.diff:  handle_cast({doit, From, MFA}, St) ->
       handle_cast({doit, From, undefined, MFA}, St);
   
  -handle_cast({doit, From, Nonce, MFA}, #st{workers=Workers} = St) ->
  +handle_cast({doit, From, Nonce, MFA}, State) ->
       {LocalPid, Ref} = spawn_monitor(?MODULE, init_p, [From, MFA, Nonce]),
  -    {noreply, St#st{workers = add_worker({LocalPid, Ref, From}, Workers)}};
  +    Job = #job{client = element(2, From), worker = Ref, pid = LocalPid},
  +    {noreply, add_job(Job, State)};
   
   
  -handle_cast({kill, FromRef}, #st{workers=Workers} = St) ->
  -    case find_worker_from(FromRef, Workers) of
  -    {Pid, KeyRef, {_, FromRef}} ->
  +handle_cast({kill, FromRef}, #st{clients = Clients} = St) ->
  +    case find_worker(FromRef, Clients) of
  +    #job{worker = KeyRef, pid = Pid} = Job ->
           erlang:demonitor(KeyRef),
           exit(Pid, kill),
  -        {noreply, St#st{workers = remove_worker(KeyRef, Workers)}};
  +        {noreply, remove_job(Job, St)};
       false ->
           {noreply, St}
       end;
  
positive.code: -include("rexi.hrl").
  -include_lib("eunit/include/eunit.hrl").
  
  -record(st, {
      workers = ets:new(workers, [private, {keypos,2}]),
      errors = queue:new(),
      error_limit = 20,
      error_count = 0
  
negative.code:     {noreply, St}.
  
  handle_info({'DOWN', Ref, process, _, normal}, #st{workers=Workers} = St) ->
      case find_worker(Ref, Workers) of
      #job{} = Job ->
          {noreply, remove_job(Job, St)};
      false ->
          {noreply, St}
      end;
  
  handle_info({'DOWN', Ref, process, Pid, Error}, #st{workers=Workers} = St) ->
      case find_worker(Ref, Workers) of
      #job{pid=Pid, worker=Ref, client=From} = Job ->
          case Error of #error{reason = {_Class, Reason}, stack = Stack} ->
              notify_caller(From, {Reason, Stack}),
              St1 = save_error(Error, St),
              {noreply, remove_job(Job, St1)};
          _ ->
              notify_caller(From, Error),
              {noreply, remove_job(Job, St)}
          end;
      false ->
          {noreply, St}
  