GitBook - Modern Publishing, Simply taking your books from ideas to finished, polished books.
DocBook - DocBook is a schema (available in several languages including RELAX NG, SGML and XML DTDs, and W3C...
MkDocs - Project documentation with Markdown.
Tectonic typesetting - A modernized, complete, standalone TeX/LaTeX engine.
Docusaurus - Easy to maintain open source documentation websites
SILE - SILE is a typesetting system inspired by TeX and InDesign, but seeks to be more flexible...