In Go we have https://github.com/alecthomas/chroma, and I implemented the lexer that the Caddy docs use for syntax highlighting the Caddyfile (see https://caddyserver.com/docs/caddyfile/concepts for example). What's cool about this is Caddy is serving the site from markdown files rendered via Go templates, with Chroma for code blocks. So Caddy can highlight its own config.