FairBox, a family expense ledger with a theory of kinship

Field notes

FairBox organizes shared costs around nuclear families nested inside reusable extended-family or friend circles. Participants can record attendance by person and day, including partial child weighting, while one treasurer or several co-treasurers manage the event through locking. The examples cover groceries, lodging, fuel, attractions, grandparent subsidies, and carried-over balances, suggesting a system designed for repeated, socially complicated gatherings rather than a one-off bill splitter.