Feature Flags

Feature flags, also known as feature toggles, are a powerful technique in software development that allows teams to turn features on or off without deploying new code. This enables safer testing in production, gradual rollouts, and the ability to quickly revert changes.


At Google, feature flags are extensively used to test new features in products like Gmail. They enable the team to selectively roll out features to users, gather feedback, and make adjustments before a full launch.