Bridge adapter

The bridge has three duties: durable ingest streams, request/reply queries, and registration of ephemeral live subjects. The v1 adapter is NATS JetStream. A new bridge adapter implements the bridge-ports contract — the cross-service shape is unchanged.

Surface

interface BridgePort {
  // 1. Durable streams (ingest)
  publish(subject: string, payload: Uint8Array, opts?: PublishOpts): Promise<Ack>;
  consume(consumerName: string, subject: string, handler: ConsumeHandler): Subscription;

  // 2. Request/reply (queries)
  request(subject: string, payload: Uint8Array, opts?: RequestOpts): Promise<Reply>;
  reply(subject: string, handler: ReplyHandler): Subscription;

  // 3. Ephemeral subjects (live fanout)
  ephemeralSubject(prefix: string): { subject: string; close(): void };
  publishEphemeral(subject: string, payload: Uint8Array): void;
}

What you must preserve

• At-least-once durable delivery for ingest streams.
• Ack-after-commit semantics on the consumer side.
• Ephemeral subject lifecycle — the subject is alive only while the registering service holds the handle.
• Authorization is upstream — the bridge does not authenticate; the publishing/consuming services do.
• Public boundaries stay unchanged — adding a bridge adapter must not add public NATS, public SurrealDB, REST telemetry reads, or frontend-direct realtime protocols.