# Put it all together: an intermediate streaming system must scale via consumer groups with committed

Canonical URL: <https://datadriven.io/problems/put-it-all-together-an-intermediate-streaming-system-must-s-207b7188>

Domain: Pipeline Design · Difficulty: medium

## Problem

Put it all together: an intermediate streaming system must scale via consumer groups with committed offsets, window on event time with watermarks, route bad events to a DLQ, and write idempotently so rebalances and replays stay correct.

## Related

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