# A 14-day-old consumer-logic bug in the Flink job was just discovered

Canonical URL: <https://datadriven.io/problems/a-14-day-old-consumer-logic-bug-in-the-flink-job-was-just-di-8c5e4503>

Domain: Pipeline Design · Difficulty: medium

## Problem

A 14-day-old consumer-logic bug in the Flink job was just discovered. Plan the replay. Walk the section's three-leg checklist on this canvas: a retention window long enough to cover the cycle, an addressable-position mechanism, and an idempotent destination that absorbs replay. Make the structural change for any leg the canvas does not already satisfy.

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