1 min lesson
Integration & reliability patterns
Talk this through in your own words: "You're integrating the billing system with a payment processor over webhooks. What's the strongest way to describe how you guarantee correctness?" Finish with the next move.
Step 1 of 3
O2C is a distributed system that happens to move money. The hard part is not any single service, it is keeping billing, the payment processor, the revenue subledger and the GL consistent when the network is flaky and services retry. The patterns below are the ones a finance-systems engineer is expected to reach for by name.