Code RoomStale personalized content after rollback
MediumPrep Room Coding #2442

Stale personalized content after rollback

On-callStorage & CDNReliability & on-callMid–Senior~35 min

v90 of a content API deployed at 10:00 and briefly served responses with a wrong Cache-Control (it set 'public, max-age=86400' on personalized, user-specific pages). You catch it and roll back to v89 at 10:08. But users keep reporting they see other people's personalized content for hours after the rollback, even though the code is correct now and the deploy dashboard is green. Triage and mitigate.

What a strong answer looks like

Stop the bleeding first (mitigate), then form hypotheses from real signals. Separate root cause from symptom, communicate status as you go, and close with what prevents a repeat.

0:00 of about 35 min
Which questions mattered is sealed until you submit. Telling you now would just be handing over the edge cases.