Single-node · In-memory · gRPC

Heads up: I ended up switching to NATS + PostgreSQL. If you need consumer groups, bare NATS won't help — you need JetStream, which requires persistence. tinybroker fills the gap when you want in-memory consumer groups with no persistence overhead. The code works and is free to use; just know why you're reaching for it.

Common scenarios where tinybroker’s combination of simplicity, low footprint, and gRPC interface makes it the right tool.

k3s / Kubernetes sidecar

Deploy tinybroker as a per-namespace sidecar alongside your application pods.

Intra-replica communication

Coordinate between replicas of a horizontally-scaled service without sticky sessions or shared state.

WebSocket & realtime coordination

Fan-out server-sent events and WebSocket messages across backend nodes without sticky sessions.

Realtime notifications

Push events from any service to any subscriber without polling or a dedicated notification platform.