The payment was successful. The ledger had been updated. The transaction had completed. Everything looked correct from the backend. And yet the customer opened the app and saw the old balance. They refreshed. Still the old balance. They checked again.…
The transaction used to be simple. At least, it looked simple from the application’s perspective. A customer placed an order. The system processed the payment. The order was created. Inventory was reserved. The ledger was updated. The customer received a…
It was 2AM. Most of the engineering team was asleep. The payment system was processing transactions normally. Then an alert fired. Duplicate charges were increasing. Not thousands. Not enough to immediately bring the entire system down. But enough to tell…
