I mean, the JS itself is the 200 LOC, so it's not trivial, but feel free to crib my source as a start. The partials are really straightforward, though — my layouts/microposts/single.html just brings in the webmentions.html partial with one tag at the right part of the layout (i.e. almost the bottom) and then that JS does the work of... whatever you want. You could start just iterating the contents of any webmentions array pulled in as an unnumbered list, then iterate your presentation from there.