"Tell me about a time you owned a model in production end-to-end including monitoring and incident response"

I owned a real-time personalization model end-to-end — training, deployment, and production health. Before launch, I defined three monitoring contracts: feature freshness SLAs, prediction distribution thresholds, and a business metric dashboard tied directly to downstream conversion. I wrote runbooks for each alert class so on-call engineers could triage without me. Six weeks post-launch, my freshness alert fired at two a.m. — before any customer impact was measurable. I traced it to an upstream pipeline schema change, patched it in four hours, and filed an architectural proposal to add schema validation as a pre-serve gate. The incident led to a team-wide standard we adopted across three other models.