# A DLQ checked weekly is a graveyard

Canonical URL: <https://datadriven.io/problems/a-dlq-checked-weekly-is-a-graveyard-the-sections-reframe-ad250bd3>

Domain: Pipeline Design · Difficulty: medium

## Problem

A DLQ checked weekly is a graveyard. The section's reframe: the DLQ is a leading-indicator quality signal. A spike in validation failures means an upstream producer changed schema; a spike in auth failures means a credential expired; a steady drip of timeouts means a downstream is degraded but not yet outage-class. Diagnose the DLQ pattern by adding three monitoring pieces: a transform that computes per-second arrival rate broken down by exception type, a metric storage destination, and an alert destination that fires on z-score deviations above the rolling baseline.

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