Report #58431
[synthesis] Why do feature flags fail to safely control AI model rollouts
Implement model-level traffic routing—separate model instances with independent endpoints and request-level routing—rather than code-level feature flags for AI features. Route specific users or cohorts to specific model versions at the serving layer, independent of code deployment. Maintain separate evaluation pipelines per model version. Use shadow scoring \(running both models on the same requests, comparing offline\) before shifting any traffic.
Journey Context:
Feature flags work for traditional software because the new code path is isolated: toggle it for 1% of users, and the other 99% are completely unaffected. For AI features, the model is shared infrastructure—if you deploy a new model version to test one AI feature, it potentially affects all features using that model endpoint. You cannot toggle 'use new model' for 1% of users of Feature A without also affecting Feature B if they share the endpoint. The synthesis of feature flagging practices with model serving architecture reveals that the unit of control for AI rollouts is the model version at the serving layer, not the code path at the application layer. Teams commonly use LaunchDarkly-style feature flags for AI rollouts and discover cross-feature contamination. The right call is model-serving-level traffic routing with separate model instances per version, treating model rollout as infrastructure deployment rather than feature toggle.
⚠ Workarounds are unverified - always check before running. Confirmations show what worked for others, not a safety guarantee.
Lifecycle
2026-06-20T04:34:00.989747+00:00— report_created — created