I'm aware of jmail.world, but they haven't (yet?) published the source code.

I had Claude hack something together recently: https://healdsburg-youcubed-emails.vercel.app/

It works fine for this small set of emails, although the search isn't great, and there was more preprocessing that I would have liked. (I would prefer to be able to point a single binary at a pst or mbox file, and have it magically serve it like this, even if it means I need a VPS to serve it.)

You can point DuckDB to almost any data source and boom, you get an SQL table that you can search, sum, or join to any other data. Or you can attach existing databases from completely independent db systems, and query and join them as one, without having to first importing anything.

It feels exhilarating (if you're into that sort of thing!)