When it comes to text, I would recommend using a simple XML format as the single source of truth and generating other formats from that. My own publishing pipli

When it comes to text, I would recommend using a simple XML format as the single source of truth and generating other formats from that. My own publishing pipline is: a) XML directly to HTML via Saxon XSLT. b) XML to LaTeX via Saxon XSLT. Then LaTeX to PDF via pdflatex/lualatex. I have an input folder and two output folders (for HTML and PDF). I use a batch file that runs all files placed in the input folder through the pipeline. If I want to change the Layout a bit, I modify the the XSLT and re-run the batch file with all the old XML sources. That has been working like magic for more than a decade, with very little changes after the initial effort of defining the XML format and writing the XSLT scripts.