Design a Payment System — Idempotency, Reconciliation, and the Boring Discipline
Payment system design from first principles: ledger, idempotency keys, reconciliation against PSP, retries, and how to keep money straight at scale.
Payment system design from first principles: ledger, idempotency keys, reconciliation against PSP, retries, and how to keep money straight at scale.
Production-grade payment system design. Idempotency keys, double-entry ledger, async fulfillment, webhook handling, PCI scope, fraud rails, and the patterns Stripe-style products use.