Ecosystems:
JavaScript
node-pandoc-katex
Very simple pandoc filter to prerender LaTeX math using KaTeX. You just need to load the katex.css (or katex.min.css) file; with pandoc, this is done with --css=katex.min.css assuming katex.min.css is in the working directory. You can get the css file from https://katex.org/docs/browser.html.