anchor.diff:           ]).
   
   produce_javascript(RD, Ctx) ->
  -    {ok, Script} = file:read_file(?SCRIPT_INTERNAL),
  +    {ok, Script} = file:read_file(wm_path(?SCRIPT_INTERNAL)),
       {Script, RD, Ctx}.
   
   produce_map(RD, Ctx) ->
  -    {ok, Map} = file:read_file(?MAP_INTERNAL),
  +    {ok, Map} = file:read_file(wm_path(?MAP_INTERNAL)),
       {Map, RD, Ctx}.
   
   produce_css(RD, Ctx) ->
  -    {ok, Script} = file:read_file(?STYLE_INTERNAL),
  +    {ok, Script} = file:read_file(wm_path(?STYLE_INTERNAL)),
       {Script, RD, Ctx}.
   
   %%
  
positive.code: -record(ctx, {trace_dir, trace}).
  
  -define(MAP_EXTERNAL, "static/map.png").
  -define(MAP_INTERNAL, "deps/webmachine/docs/http-headers-status-v3.png").
  -define(SCRIPT_EXTERNAL, "static/wmtrace.js").
  -define(SCRIPT_INTERNAL, "deps/webmachine/trace/wmtrace.js").
  -define(STYLE_EXTERNAL, "static/wmtrace.css").
  -define(STYLE_INTERNAL, "deps/webmachine/trace/wmtrace.css").
  
  %%
  %% Dispatch Modifiers
  
negative.code:                      Ctx}
              end;
          ?MAP_EXTERNAL ->
              {filelib:is_file(wm_path(?MAP_INTERNAL)), RD, Ctx};
          ?SCRIPT_EXTERNAL ->
              {filelib:is_file(wm_path(?SCRIPT_INTERNAL)), RD, Ctx};
          ?STYLE_EXTERNAL ->
              {filelib:is_file(wm_path(?STYLE_INTERNAL)), RD, Ctx};
          TraceName ->
              TracePath = filename:join([Ctx#ctx.trace_dir, TraceName]),
              {filelib:is_file(TracePath), RD, Ctx#ctx{trace=TracePath}}
      end.
  
  wm_path(File) ->
      filename:join(code:lib_dir(webmachine), File).
  
  content_types_provided(RD, Ctx) ->
      case wrq:disp_path(RD) of
  