Message Queue Simulator — Interactive System Design Lab
Produce messages and watch multiple consumers process them in parallel. Toggle between at-least-once and at-most-once delivery modes, observe how ordering guarantees hold or break under load, and understand how queues decouple services so producers and consumers can fail independently.
Drop messages into a queue, watch consumers race to process them, and break delivery guarantees to see why idempotency matters.
This free interactive simulation runs directly in your browser — no account needed. Adjust the parameters and watch how the system responds in real time.
Concepts covered
- message queue
- producer consumer
- Kafka
- RabbitMQ
- at-least-once
- exactly-once
- async messaging
Read the guide
- Message Queues — The secret to calming down a chaotic system. Learn how to decouple your services, smooth out traffic spikes, and choose between the two giants: RabbitMQ and Kafka.
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