Change Notification and Event Streaming

Event generation

Each successful revision publication emits an event:

{ "entity_id": "Q123", "revision_id": 42, "timestamp": "...", "user_id": "...", "type": "entity_updated" }

Event transport

Kafka / PubSub / Pulsar

At-least-once delivery

Ordered per entity partition key

Event consumers

Watchlist / subscription service

Recent changes feeds

Search indexers

Data dumps

External mirrors

MediaWiki never fans out writes.