Persist external-call intent with business data, claim work safely across replicas, classify retries, handle ambiguous HTTP outcomes, and use Kafka only through a durable outbox or CDC boundary.
Choose a tenant-isolation model, derive tenant identity from authenticated claims, use Hibernate tenant filtering with PostgreSQL row-level security, and test every path that can cross tenant boundaries.
Build a practical test strategy for Spring Boot microservices with fast domain tests, PostgreSQL and Kafka integration tests, message-contract checks, deterministic asynchronous assertions, and a small set of end-to-end flows.
Define a measurable convergence contract for event-driven Spring Boot services, protect projections from duplicate and stale events, provide read-your-writes behavior, reconcile durable state, and repair drift safely.
Build a reactive Spring Boot service without hiding blocking work: model WebFlux demand, use R2DBC transactions correctly, integrate Kafka with explicit delivery semantics, isolate unavoidable blocking calls, and test cancellation and backpressure.