What's a feature flag and why does its absence matter here?
A feature flag is a runtime switch that lets a team enable new code for a small percentage of traffic first, and roll it back instantly without a redeploy if something breaks. The buggy quota logic here shipped active in every region from day one, with no flag. That single missing safeguard is why a bug that should have surfaced in a canary region instead surfaced everywhere at once.
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The Google Cloud Outage That Started With One Missing Null CheckOne unprotected code path in Google Cloud's Service Control took down Spotify, Discord, and Cloudflare auth in minutes. Here's the anatomy of the failure.
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