this is a great idea! i'm all for making math typesetting more accessible and useful!

i am wondering why they use a headless to render from KaTeX though. Is there an advantage to doing that compared to, say, shelling out to xetex? You'd get better compatibility with potentially useful libraries like tikz that way (and potentially higher throughput/lower costs), at the cost of investing some thought in sandboxing. Curious about the considerations behind that decision.