SQLite

https://sqlite.org/

https://sqlite.org/fiddle/

https://blog.wesleyac.com/posts/consider-sqlite

100000 TPS over a billion rows: the unreasonable effectiveness of SQLite - https://andersmurphy.com/2025/12/02/100000-tps-over-a-billion-rows-the-unreasonable-effectiveness-of-sqlite.html

I'm All-In on Server-Side SQLite - https://fly.io/blog/all-in-on-sqlite-litestream/