Kafka & pub/sub.
A newspaper: published once, and any number of subscribers read it at their own pace.
- Still calling everyone…1
The old way: phone every interested party, one by one. Slow and brittle.
- 2
Instead, publish once to an ordered log — like printing the paper.
- 3
Many subscribers read the same log, each tracking its own place.
- Catch up later? Fine.4
A slow reader doesn’t hold up the others — the paper just waits to be read.
- 5
The log is kept, so a reader can replay from the start when needed.
- 6
Producers and consumers never touch directly — add either side freely.
Semicolony semicolony.dev/eli5/kafka/comic