Context

A microservice system with independently owned services (for example order, payment, inventory, notification).

Trigger

A team changes one service (internal model, API, or event schema) to implement a new feature.

Acceptance Criteria

  • Over a rolling 90-day window, architecture/compliance checks report 0 direct dependencies on another service’s internal implementation artifacts (for example internal packages, private libraries, or shared source).
  • Cross-service direct database access is 0; communication is only via explicit API/event contracts.
  • Over a rolling 90-day window, at least 85% of production changes affect one service only, and 0% affect more than 2 services.
  • For contract changes introduced in a rolling 90-day window, required code changes are limited to at most 2 downstream consumers at the 95th percentile.
  • In production, at the 95th percentile over a rolling 90-day window, a single service can be deployed or rolled back in <= 15 minutes without coordinated redeployment of other services.