I also did this a while back (maybe 10 years ago). I started with an XML document and transformed to HTML and TeX via XSLT. I generated PDF using TeX and a pla

I also did this a while back (maybe 10 years ago). I started with an XML document and transformed to HTML and TeX via XSLT. I generated PDF using TeX and a plain text version from the HTML using "links -dump". If I were to wrote it again today, I'd probably be more likely to start with something like yaml and write a quick python script to generate the TeX and HTML. (My TeX is rusty, but it does a good job setting type. A non-TeX alternative would be XSL-FO + FOP.)