Toggle is a user interface element that allows users to update their preferences, settings, and other types of information. Toggles are generally easy to understand and use, but they can be confusing if not used correctly. Toggle switches should have clear labels that describe what will happen when the toggle is pressed. They should also be visually clear, and they should have a high contrast color to make it easier for users to distinguish between on and off states. Finally, they should always provide immediate results, or at least no more than a few seconds of delay after pressing the toggle.

In most cases it’s good to keep toggle configuration in source control, especially if your team uses a continuous deployment system like CI/CD. However, as the number of toggles grows it becomes more cumbersome to manage changes via files. For this reason many teams move toggle configuration to some type of centralized store, often an existing database. This can be a great way to reduce the cycle time of validation and improve the all important feedback loop that CI/CD provides.

Another thing to keep in mind is that it’s important to test the feature toggle configuration that you expect to be live in production, as well as any fallback configuration where those toggles are flipped Off. In addition, it’s typically a good idea to test with all toggles flipped On as well, to ensure that any new or unreleased behavior is still working properly. This is particularly true for things like Experiment Toggles, which are often used to perform multivariate or A/B testing on features.