Tessera
Settle up with the fewest moves.
What it is
Tessera settles shared expenses among a group with the fewest possible transfers. It nets everyone down to a single balance in integer cents, then greedily matches creditors to debtors, guaranteeing at most n-1 transfers. It is a from-scratch, dependency-light build whose books are kept exact by 10 tested invariants, and you can download and run it locally.
Net everyone to a single balance in integer cents, then greedily match creditors to debtors - at most n−1 transfers. 10 tested invariants keep the books exact.
What's inside
The full source, the tests, and CI. Open it, read it, change it. A zero-dependency core, free, in the MIT spirit.
Run it after unzip
pnpm install && pnpm dev