Being only a few hundred lines of code is a pro, not a con (it's 2,800 including tests: https://tools.simonwillison.net/sloccount?repo=https%3A%2F%2... - lines counted by my vibe-coded port of the classic Perl SLOCCount tool to run in a browser using Perl-in-WebAssembly.)

It does use transactions in the form of savepoints which means they can be nested: https://github.com/simonw/sqlite-history-json/blob/53e66b279...

Transactions are tested here: https://github.com/simonw/sqlite-history-json/blob/53e66b279...

I lead with sqlite-history-json because I think it's the most impressive of the bunch - it solves a difficult problem in an elegant way with code I would have been proud to write by hand.