NoDB: Processing Payments Without a Database

2024-12-21

Alvaro Duran's "The Payments Engineer Playbook" introduces a revolutionary approach to payment system design: processing payments without a database. He argues that the prevalence of asynchronous programming stems from the assumption of database necessity. Using event sourcing, each step in the payment process is recorded as an event, not as a persistent state. These events are temporarily stored in memory, and the system reconstructs the payment status from the event stream, eliminating the need for persistent storage. This high-performance, high-reliability approach, inspired by high-frequency trading, allows for quick recovery from outages through hot backups. The article details this concept using a payment flow example and looks toward future applications in payment systems.