Payments System
Implement payment flows safely with auditability and retry resilience.
Recommended approach
- Keep payment provider integration isolated in a dedicated module.
- Use idempotency keys for charge/checkout operations.
- Persist payment state transitions explicitly.
Alternatives and when to choose them
- Hosted checkout only for low-complexity products.
- Custom payment orchestration when multiple providers are required.
Implementation checklist
- Model payment lifecycle states and transitions.
- Verify webhook signatures and replay protection.
- Add reconciliation jobs for eventual consistency.
Common pitfalls
- Treating provider callback success as guaranteed final state.
- Missing refund/chargeback paths in data model.