Hacker News Reader

I had an idea a while back to to this end. Markdown files as a database of sorts with queries, validations, actions/plugins, etc. written in Javascript. I documented the interfaces but haven't had time to implement it.

https://github.com/fictorial/gg

https://github.com/fictorial/gg/tree/master/doc

I imagine you could use recfmt templates [0] which generate valid Markdown, and use (pp [1] and) pandoc [2] to (pre)process into the desired final format.

[0] https://www.gnu.org/software/recutils/manual/Templates.html#...

[1] https://github.com/CDSoft/pp

[2] https://pandoc.org/

I'm not sure what you mean "data fields within markdown".

You could definitely use markdown within fields of a recfile. There would be some multi-line syntax you wouldn't be able to use, because it would conflict (e.g. '+' unordered lists), but other than that you could mark up text with Markdown, no worries.