NATS Mastery (Senior → Principal)

Operate

• Start from messaging semantics: ephemeral pub/sub, request/reply, durable streams, or control-plane signaling.
• Treat subject design, consumer semantics, retention, and topology as first-class architecture concerns.
• Prefer simple subject hierarchies and explicit delivery semantics.
• Design for debuggability and operator clarity before chasing messaging cleverness.

Default Standards

• Subject naming should encode bounded, meaningful routing intent.
• JetStream retention and ack behavior must match business semantics.
• Consumers must be idempotent where durability and replay matter.
• Multi-tenant usage needs policy before it needs scale.
• Observability should reveal lag, redelivery, and cluster health clearly.

References