Which method involves programming features with a switch to turn them on or off?

The method that involves programming features with a switch to turn them on or off is known as Feature Flags. This technique allows developers to control the visibility and availability of new features in a live environment without deploying new code. By toggling the flag, teams can enable or disable features for specific users or groups, which makes it easier to test and iterate on features based on user feedback and requirements.

Feature Flags are particularly useful for continuous integration and delivery practices because they enable more granular control over what parts of the application are available at any given time, facilitating safer deployments and reducing the risk associated with releasing incomplete or untested features. By managing features in this way, organizations can gradually roll out updates, perform A/B tests, or manage experimental features while maintaining stability in their production environments.

This functionality is essential for agile development practices, as it allows teams to experiment with new ideas and receive feedback without the need for full, traditional deployment processes each time a change is made.