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[c0d0g3n]

After inspecting the code, it seems there is an undocumented feature: markedRenderer. See this gist for more info. It would be nice to add that to README.md so people can know about this shortcut :).

Also, at first it wasn't clear to me that I had to put markedOptions in docpadConfig.plugins.marked. (I tried things like docpadConfig.plugins.markedOptions and docpadConfig.plugins.marked.[marked setting here]. This was probably due to me not interpreting correctly, but some extra clarity never hurts.

I suggest something like this snippet:

You can customise the Marked options by using the `markedOptions` object. Custom marked renderers can be added via `markedRenderer`, like so:
docpadConfig =
    plugins:
        marked:
            markedOptions:
                # customize Marked here... (see https://github.com/chjj/marked#options-1)
            markedRenderer:
                # custom renderer methods here...
                # same as passing a custom renderer instance to `docpadConfig.plugins.marked.markedOptions.renderer` (https://github.com/chjj/marked#renderer)
                # for accepted keys, refer: https://github.com/chjj/marked#block-level-renderer-methods and https://github.com/chjj/marked#inline-level-renderer-methods