What does 'Feature Toggle' allow developers to do?

Feature Toggle is a powerful technique used in software development that enables developers to enable or disable specific features in production environments without having to redeploy the application. This approach allows for a more agile and flexible development process, as it gives teams the ability to merge code that contains new features into the main codebase without exposing those features to end users until they are ready.

By using Feature Toggles, developers can conduct thorough testing of new features in live environments while minimizing the risk associated with deploying unfinished or untested functionality. Additionally, it provides a mechanism for rolling back features quickly if they do not perform as expected or cause issues. Therefore, the core functionality of Feature Toggle is about making these features dynamically controllable, enhancing the overall deployment and development workflow.

The other options touch on aspects of feature management, but they do not accurately represent the primary purpose of Feature Toggles. For example, while enhancing user access control is important, it does not capture the essence of enabling or disabling features at runtime without deployments, which is the main benefit of using Feature Toggles. Similarly, tracking performance metrics and disabling all features during user testing are broader concepts that do not specifically relate to the ability that Feature Toggling provides.