           title: list_title(tag, proj),
           posts: posts,
           url: Path.join([proj.base_url, list_dir, "page-#{page}.html"]),
-          output: Path.join([proj.dest, list_dir, "page-#{page}.html"])
+          output: Path.join([proj.dest, list_dir, "page-#{page}.html"]),
+          extras: %{}
         }
       end)
 

          url: binary(),
          prev_url: binary() | nil,
          next_url: binary() | nil,
          output: binary()
        }

  @type maybe_tag :: Tag.t() | nil

    :url,
    :prev_url,
    :next_url,
    :output,
    :extras
  ]

  @spec generate(maybe_tag(), [map()], map()) :: Result.t([t()])
