anchor.diff:  -spec init(riak_pipe_vnode:partition(), riak_pipe_fitting:details()) ->
            {ok, state()}.
   init(Partition, #fitting_details{arg={Phase, Arg}}=FittingDetails) ->
  -    {ok, #state{p=Partition, fd=FittingDetails, phase=Phase, arg=Arg}}.
  +    case init_phase(Phase) of
  +        {ok, LocalPhase} ->
  +            {ok, #state{p=Partition, fd=FittingDetails,
  +                        phase=LocalPhase, arg=Arg}};
  +        {error, Error} ->
  +            {error, Error}
  +    end.
  +
  +init_phase({jsanon, {Bucket, Key}}) ->
  +    %% lookup source for stored-js function only at fitting worker
  +    %% startup, and convert to {jsanon, Source}
  +    {ok, C} = riak:local_client(),
  +    case C:get(Bucket, Key, 1) of
  +        {ok, Object} ->
  +            case riak_object:get_value(Object) of
  +                Source when is_binary(Source) ->
  +                    {ok, {jsanon, Source}};
  +                Value ->
  +                    {error, {jsanon, {invalid, Value}}}
  +            end;
  +        {error, notfound} ->
  +            {error, {jsanon, {notfound, {Bucket, Key}}}}
  +    end;
  +init_phase(Other) ->
  +    %% other types need no initialization
  +    Other.
   
   %% @doc Process evaluates the fitting's argument function, and sends
   %%      output downstream.
  
positive.code:             {error, "{strfun, {Bucket, Key}} is not yet implemented"};
          {strfun, _Source} ->
              {error, "{strfun, Source} is not yet implemented"};
          {jsanon, {_Bucket, _Key}} ->
              {error, "{jsanon, {Bucket, Key}} is not yet implemented"};
          {jsfun, Name} ->
              if is_binary(Name) -> ok; %% TODO: validate name somehow?
                 true ->
  
negative.code:     exit({strfun, {Bucket, Key}});
  map({strfun, Source}, _Arg, _Input) ->
      exit({strfun, Source});
  %% {jsanon, {Bucket, Key}} is converted to {jsanon, Source} in init
  map({jsfun, Name}, Arg, Input) ->
      map_js({jsfun, Name}, Arg, Input);
  map({jsanon, Source}, Arg, Input) ->
  