During his Clojure years Karsten Schmidt learned of Hiccup, that community's de-facto convention/format to encode structured documents (HTML/SVG etc.) using S-expressions and nothing but the core language literals for vectors & maps/objects. post 
, github
> Since 2016 I've adapted and extended that approach for JavaScript/TypeScript – https://thi.ng/hiccup – and it's since become one of the pillars for much of my other work, incl. as generic intermediate representation when converting between all sorts of structured data formats – e.g. generating & outputting geometry shape hierarchies for SVG, Canvas API or for pen plotters … or parsing Markdown to Hiccup then processing/transforming the whole tree using the full flexibility of the host language & libraries and then converting to HTML or whatever …