Inside Gulfstream: Uber's $217B zero-sum payments ledger
Uber's payments platform, nicknamed Gulfstream, now moves close to 2x its $217 billion in annualized gross bookings and keeps ledger balances for over 1.2 billion entities. The keystone design: immutable money orders that always sum to zero, enforced by double-entry bookkeeping, so no money is ever created or destroyed. Adjustments are written as new orders, never edits. Notably, the DynamoDB-based ledger gives each entity one row with pruned sub-accounts to manage size.