Microservices & distributed systems — your daily reality in banking, but the interview asks about the sharp edges. Guided order first, full note grid below.
Learn in this order
- Communication — sync (REST/gRPC) vs. async (events); when each
- Resilience — retry, circuit breaker, bulkhead, timeout
- Distributed Transactions — Saga (choreography vs. orchestration), why 2PC is avoided (the “distributed tx” pain — build next)
- Kafka — partitions, ordering, consumer groups
- Idempotency & Outbox — exactly-once in practice (build next)
Where they probe
“How do you keep data consistent across services without a distributed
transaction?” → Saga + outbox. Have that answer ready; it’s the classic trap.