A toggle is a switch that can be set to two different states: on or off. It’s used in software, programming, and user interfaces. Unlike a switch that has physical dimensions, the toggle is a purely digital concept that can be represented by a Boolean variable in your code.
The main purpose of a toggle is to control the behavior of your application. For example, you can use a toggle to disable certain features during high latency periods or to roll out a new feature to select users while retaining the old behavior for all others. This allows you to manage your product with the confidence that you’ll be able to fix bugs without accidentally making things worse.
Toggles are a valuable tool in your continuous delivery process because they allow you to experiment with features with a small segment of your audience before they are rolled out. This helps you to reduce the risk that a new feature will be a flop, and it also lets you validate your features with real users before rolling them out to the entire audience.
Another important use of toggles is that they let you create and test A/B tests with minimal risk to your production system. Toggle-based A/B tests allow your engineering team to deploy a new version of your app to users with the new feature enabled and all other users with the feature disabled. This way, you can see how your new feature performs in a real-world environment and then remotely roll it back or make changes to fix any problems that come up.
Using toggles for A/B testing also supports agile development approaches by allowing you to release features on a schedule that would otherwise require a lengthy review and testing cycle with a code branch under more traditional waterfall processes. Because the new feature is only deployed to a small group of users, you can test them with real-world data and determine whether or not it’s ready for broader rollout before moving it into your trunk code repository.
Adding a toggle to your application can be as simple as adding a new boolean variable in your source code and declaring the variable’s state as either ON or OFF. At runtime, your platform can query the toggle’s configuration from an external data source or a service like Kameleon and execute its function if it returns as ON. Likewise, if the configuration is OFF, your platform will not execute its function. Managing your toggles and removing them as soon as they’re no longer needed will help you keep your code clean and reduce technical debt. Using a feature flag management platform like Kameleon will simplify this process even further. It will allow you to centrally store and manage all your toggles in one dashboard so that they’re easy to find and manage as your application grows.