A toggle is a switch that has two positions, ON and OFF. It is commonly used in technology, computing and programming to change between different states or options. For example, you can use a toggle to change the display of your aim bot’s status on the screen or to change the view from stream to map mode in a game. Toggles are also popular in responsive design as they allow us to show or hide navigation menus, sidebars and other elements based on device or screen size.
Typically toggles are configured through some type of centralized config management system. This can range from static commenting of code through to more advanced solutions which provide dynamic re-configuration at runtime. Using a centralized system makes it easier to manage and test changes. It also reduces the need to re-deploy a production artifact in order to test a toggle change since the configuration is now managed centrally. This has a direct impact on the cycle time of validation, which in turn impacts the all important feedback loop of CI/CD.
When a team decides to release a toggle they are wise to make sure that they test the new configuration along with any existing or legacy behavior that is enabled when the toggle is flipped ON. This can be done by adding a toggle removal task to the team backlog when the feature is initially introduced or, more commonly, by placing “expiration dates” on toggles so that they will fail if they are not removed prior to the expiration date.
In addition to the advantages mentioned above there are a few things to consider when designing a toggle. For instance, it’s important that the label for the toggle clearly communicates what is being controlled by that switch. This can be achieved through appropriate iconography or by ensuring that the toggle’s appearance is updated when its state changes. Also, it’s important to keep in mind that a toggle should not be used where immediate results are required. For example, it would be inappropriate to use a toggle in a form that requires the user to click a Submit or Confirm button in order for their changes to take effect. If such an approach is desired, it’s best to replace the toggle with a checkbox instead.
Savvy teams treat their toggle inventory like any other inventory and seek to keep it as low as possible. This means they will actively work to remove any toggles that are no longer needed from the codebase and will also try to avoid creating any toggles that might become accidentally used in future releases. Some teams even go as far as to place a toggle removal task on their backlog or to add a toggle expiration date so that they will be forced to review the impact of a particular change before committing to it in production.