3-9 replicas (HPA) previously relied on implicit scheduler spreading. ScheduleAnyway (not DoNotSchedule) so pods still get scheduled if a node is briefly unavailable, just less evenly.
- Kafka 3-broker cluster (RF=3, min-ISR=2) - kmsvc SQS-like API on Kafka - Redis dedup (standalone, can extend to HA) - Temporal workflow orchestration (Cassandra backend)