A toggle is a switch that has two positions, on or off. A toggle is found in hardware, such as a keyboard’s Caps Lock and Num Lock buttons, or software, where it is used for things like options menus and the on/off button on a computer. It is also used in the verb form, toggle or toggling, to move back and forth between two states such as the screens of a video chat or the case of selected text on a keyboard.
A collapsible toggle or accordion can be a great way to structure content on a page in a way that minimizes scrolling and allows visitors to quickly find the content they are looking for. When used appropriately toggles can help reduce the amount of clutter on a page and increase user engagement.
Toggles are a great tool for managing the implementation of new features and settings. However, when used incorrectly they can create confusion and make it difficult for users to understand what effect a change will have on the system. When using toggles ensure they are labeled clearly and use standard visual design conventions to indicate their state. Additionally, be sure to test them with a variety of users and consider implementing a toggle-specific help topic for new or confused visitors.
Many teams also test their Feature Toggles with both the toggles they intend to release flipped On and the fallback toggles (i.e. the default configuration) flipped Off. This helps to prevent surprise regressions in a future release and allows for testing the actual impact of a change. Savvy teams also keep track of the number of toggles they have in production and are proactive about removing toggles when they’re no longer needed. Some teams even put “expiration dates” on their toggles so they’ll fail a test if they aren’t removed by a certain date.
One drawback to the feature flag approach is that when a toggle needs to be re-configured it must be manually re-deployed into the testing environment. This can have a significant impact on the speed of validation and slows down the crucial feedback loop that is provided by CI/CD. This issue can be mitigated by exposing an endpoint for dynamic in-memory re-configuration of a toggle. However, this type of override comes with a price and is only suited for cases where the toggle configuration is unlikely to change. For other situations, such as Experiment Toggles, a more dynamic configuration method is necessary.