I published a new tutorial on PrismJS: https://alchemist.camp/articles/phoenix-prism-syntax-highlighting
It’s a quick guide to get it set up on Phoenix (or just about any back-end framework that takes an agnostic approach towards JS). The code shown in the tutorial itself uses this setup.
PrismJS is a great option for code syntax highlighting. It supports a vast array of plugins and the total script weighs in at just 2k, gziped. Extra programming languages add 0.3-0.5KB each and themes are around 1KB. It’s used by Stripe, along with many other companies that deeply value documentation.