ulearn/systems

topics / async-messaging

Message Queue

A generic event-driven pipeline, not one broker's API — a bounded backlog, competing or fanned-out consumers, and what actually happens when one crashes mid-job or the producer outruns them. Switch delivery modes, kill a consumer, and watch redelivery, retries and the dead-letter queue do their jobs.

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0published
0acked
0retried
0dead-lettered
0dropped (backpressure)
in transitretryingackeddead-lettered / droppedproduceridleQueue0/10 waitingC0idle0 ok · 0 failedC1idle0 ok · 0 failedC2idle0 ok · 0 failedDead-letterqueue0

Consumers

C0

idle, waiting for work

0 processed0 failed
C1

idle, waiting for work

0 processed0 failed
C2

idle, waiting for work

0 processed0 failed

Event log

Waiting for traffic…

Delivery mode

One shared backlog — each message is delivered to exactly one consumer, whichever is free first.

Broker config

backpressure, once the backlog is full

Traffic