https://itnext.io/typescript-and-turing-completeness-ba8ded8...
I'd read this long ago, but my impression was that all the hinting stuff is auto stripped out of loaded web fonts for security/performance these days (maybe after some of those early font vulnerabilities that caused NoScript to block fonts), so most of us can't use it.
That's why I was wondering if ligatures might be a reasonable hack.
That's how you can do things like https://litherum.blogspot.com/2019/03/addition-font.html https://pagedout.institute/download/PagedOut_002_beta2.pdf#p... https://aftertheflood.com/journal/the-worlds-first-code-free... https://www.coderelay.io/fontemon.html (most of these will work in a browser). I've also suggested that you can create 'prank fonts' which add in subtle typos sporadically.
Less evilly, this is what calligraphy handwriting fonts do to get convincing variation.
Assuming it’s widely implemented, it’d be hilarious to distribute files that replace their contents with a 4koma 1% of the time.