Comment by GCUMstlyHarmls

I ended up landing on https://silverbullet.md. It checks a lot of boxes for me,

- self hosted

- works offline (mostly)

- "just md" BUT

- scriptable or extendable by lua, rendered in page, eg `${1 + 1}` outputs `2`, but you can do a lot more, such as query pages and tags with a LINQ type query interface.