Events

Bakend uses an internal Event Bus so subsystems can communicate without direct coupling.

Every important action in Bakend produces an event. Examples:

users.created
posts.updated
auth.login
job.completed

See RFC-0000 for the full event model.

Event Schema

All events share the same structure:

{
  "id": "evt_123",
  "type": "users.created",
  "timestamp": "2026-06-08T12:00:00Z",
  "source": "collections",
  "payload": {
    "id": "user_1",
    "email": "john@example.com"
  }
}

Field	Description
`id`	Unique event identifier (`evt_` prefix)
`type`	Dot-separated event name
`timestamp`	ISO-8601 UTC time
`source`	Subsystem that emitted the event
`payload`	Event-specific data

Subscribing

const unsubscribe = eventBus.on("users.created", (event) => {
  console.log(event.payload);
});

unsubscribe();

Handlers may be synchronous or async. Async handlers do not block emit().

Publishing

eventBus.emit("users.created", {
  source: "collections",
  payload: { id: "user_1", email: "john@example.com" },
});

If source is omitted, it defaults to "system".

Error Handling

Handler failures are logged and isolated. A failing handler does not prevent other handlers from running, and does not crash Bakend.

Realtime (Milestone 9)

Clients subscribe to Event Bus channels over WebSocket at /api/realtime. Wildcard subscriptions (posts.*) are supported. See Realtime.

What Is Not Available Yet

Feature	Milestone
Persistent event log	Post-1.0
Per-record realtime channels	Post-1.0