Fwiw I wrote a bunch of my college papers on a version of Roff originally written by Col. G. L. Sicherman for CP/M, which I ported to Turbo C for the obsolete-when-I-got-it MSDOS laptop that I had back then. I ran that program under x64 Linux much more recently and it still worked after I ripped out some DOS stuff, despite some C anachronisms. The CP/M program is still around in old code archive sites.

I also remember writing a crude HTML to text renderer for an old Linux box because lynx -dump was too slow then. I wonder if the code I wrote is still around anywhere. Lynx on today's hardware is extremely fast.