what are pub/subs?

this is a simple piece that briefly encompasses what pub subs are, how they work & when you should use them.

what are pub/subs?

pub/sub stands for publisher/subscriber. it is a communication pattern used to stream data in real-time systems, perfect for when you need data delivered instantly, like live comments or price updates.

how do pub/subs work?

a pub/sub setup has three main parts:

• publisher: sends or publishes events
• subscriber: listens for or subscribes to events
• topic: the channel in between, managed by a message broker (like kafka, rabbitmq, or google pub/sub) that delivers messages from publishers to subscribers

publishers and subscribers are decoupled. they don’t know each other directly. the publisher just sends messages to a topic, and any subscriber to that topic automatically receives them.

when scaling, topics can be split into partitions, and each partition can be handled by a consumer group, allowing multiple subscribers to process data in parallel.

when should you use pub/sub?

pub/sub systems shine when you need real-time updates or event-driven communication, like:

• a comment or chat section for a live stream such as tiktok or youtube
• a crypto or stock price tracker updating live
• sending notifications or syncing data across distributed systems

so the next time you need real-time updates or event-driven communication, think pub/subs.

for a deeper dive with code and a mini live comment stream, see a deeper dive into pub/sub.