Payment System Design: Charge Exactly Once, Never Lose a Cent | System Design Interview, Part 1

The Problem — part 1 of the Payment System Design build. A full system design walkthrough, drawn on the board as it is argued. Every diagram is built in front of you and every decision is defended out loud, the way it has to be in the room. 0:00 Design a payment system 0:15 The timeout that charges twice 2:16 Who's involved and which steps move money 5:32 Requirements and the first sketch 9:23 Exactly once, and money that balances Playlist: Payment System Design — the complete build, in order. Part of a system design interview preparation series: full high-level design (HLD) walkthroughs for software engineering interviews, covering scalability, distributed systems, capacity estimation and the trade-offs an interviewer will push on. Every build is complete or releasing now; more in production. #systemdesign #systemdesigninterview #hld #interviewpreparation #softwareengineering #distributedsystems