Feature Flags and Progressive Delivery

Overview

Feature flags (also called feature toggles or feature switches) decouple deployment from release, letting teams ship code dark and turn it on for targeted users without a new deployment. Combined with progressive delivery strategies like canary releases, blue-green deployments, and ring deployments, they form the backbone of modern continuous delivery.

When to use: Designing a feature rollout pipeline; reviewing flag evaluation logic; auditing rollback/kill-switch implementations; designing A/B testing or experimentation infrastructure; reviewing flag hygiene and lifecycle management.

Quick Reference