Event Bus
ELI5 — The Vibe Check
An event bus is a highway for events — services publish events onto the bus, and any service that cares about that event picks it up. Nobody needs to know who's listening. It's like a radio station: you broadcast, and whoever's tuned in receives it.
Real Talk
An event bus is a communication channel that enables loosely coupled event-driven communication between components or services. Publishers emit events without knowing subscribers, and subscribers react to events without knowing publishers. Can be in-process (EventEmitter) or distributed (Kafka, RabbitMQ, AWS EventBridge). Supports both pub/sub and point-to-point patterns.
When You'll Hear This
"Publish the OrderCreated event to the event bus and let the email service pick it up." / "Our event bus decouples services so they can evolve independently."
Related Terms
Domain Event
A domain event is something meaningful that happened in your business. Not 'row updated in users table' but 'UserRegistered' or 'OrderShipped.
Event-Driven Architecture
Event-Driven Architecture is like a gossip network. When something happens (order placed!), it broadcasts the news.
Message Broker
A Message Broker is the post office of your microservices world.
Pub/Sub (Pub/Sub)
Pub/Sub is like a newspaper service. Publishers write articles and drop them off.