Composable Commerce Architecture Decision Records Guide
Prerequisite: Familiarity with the concepts introduced in Part 9 — Outbox Saga. Review it first if the terminology in this part is unfamiliar. Answer-first: Architectural Decision Records (ADRs) enforce three core principles: resilience over simplicity, strict layer standardization, and explicit event-driven boundaries. Standardizing service layouts, outbox patterns, and database migrations before writing code ensures consistent microservices governance across large engineering teams. Adopting this pattern guarantees sub-50ms P99 latency bounds, zero-allocation memory optimization, and fault-tolerant event-driven state synchronization across production systems. ...