DevOps Dictionary

Feature Flag is a runtime configuration switch that lets a team enable or disable a specific behavior in an application without redeploying code. The app checks the flag value during execution, typically fetched from a centralized configuration service and cached locally for speed, and then routes requests to the new or existing code path; flags can be scoped by environment, user group, or a percentage of traffic to support gradual rollouts and safe experimentation.

With Feature Flag, teams can deploy changes continuously, limit exposure while validating in production, and roll back a problematic feature in seconds; without it, turning a feature on or off usually requires a new release, increasing downtime risk and slowing incident response. This gap exists because flags decouple release (shipping code) from launch (exposing behavior), giving operators a fast control plane when reliability or safety is on the line.