AI Gateway Canary Deployment: Patterns for Rolling Policy and Model Changes Safely
Canary deployment for an AI gateway covers two distinct change types: model routing changes (a new provider, a new model version, a new model entirely) and policy changes (a new redaction rule, a new tool allowlist, a new rate-limit threshold). Each change type has different risk characteristics and different rollback triggers. The canary pattern at the gateway differs from a classic application canary because the unit of traffic is identity-bound and the failure modes include silent drift in model behavior. This article walks through the canary architecture for an AI gateway, the metrics that drive the rollout, and the rollback conditions that have to be wired in before the canary starts.