An interactive explainer
A queue hands the message to whoever asks first, and then it is gone. Kafka hands nothing over — it appends to a file that only grows, and each reader keeps its own place in it. That one difference is why a second team costs the writer nothing, and why you can have yesterday back.
Kafka · Event logs · Consumer offsets
Systems · Intermediate · 11 min · Why a log beats a queue when two teams want the same event — an interactive explainer on ViLearn, with a simulation and a knowledge check. All explainers.
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