Scoping a markdown lint check to changed files stopped a CI failure flood across 33 repos

A maintainer of a GitHub organization with 33 open-source repositories added a default markdownlint check to every repo at once. The check ran against all markdown files, including old READMEs and guides that had never been linted, so roughly 100 failure notifications arrived overnight. The maintainer changed the workflow to lint only the markdown files touched by each pull request. CI then went green across the repos while still catching new violations. The post argues that teams should grandfather existing issues, scope checks to changed code, and roll out tooling gradually to keep CI signals trustworthy.