# A company at 500 engineers has thousands of pipelines, half written by people who left

Canonical URL: <https://datadriven.io/problems/a-company-at-500-engineers-has-thousands-of-pipelines-half-0a9c3a10>

Domain: Pipeline Design · Difficulty: medium

## Problem

A company at 500 engineers has thousands of pipelines, half written by people who left. Deprecating an orphan pipeline whose owner left and whose consumers are unknown is genuinely hard. The section's structured ownership: team-level ownership (not personal), a quarterly ownership audit that flags orphans, and a five-phase deprecation process: candidate (consumers identified), notice (90-day sunset notice), mute writes (parallel write only, queries return deprecated warnings), stop reads (queries fail), retire (pipeline removed). Plan the sunset by adding the five-phase deprecation process on the canvas plus an ownership-audit node whose name states the cadence and the orphan-flagging rule.

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