I have been looking for exactly this for a while now:

“For my usecase, I wanted a way to:

Stash my data in its "original" JSON form Explore it later & build whatever views I want Keep costs & infrastructure complexity low Self-host it / own my data”

However, I think compression is a key part. Large scraped json datasets can be compressed by a few orders of magnitude, which is the difference between scp’ing a db up to aws in minutes vs days. SQLite has an official proprietary extension to DEFLATE backing pages, but that’s not easy to buy/distribute for hobby projects. I’ve tried row compression with zstd dictionaries and it works well, but then you lose native indexing.

Mongo wiredtiger does pretty much what I want, it’s just not a neat flat file :/