A toggle is a switch between two different settings or states: one option is active and the other is not. The term can be applied both to software (such as the Caps Lock and Num Lock switches on a keyboard) and hardware (a rocker switch that is turned either way). In web development, the term can also refer to a button or menu item that has only two states. For example, the “Copy Code” button in the Content Toggle Item is a toggle that allows you to copy and paste code from the page into your own project.
The toggle is an important tool for managing complex systems that have many features. For example, a typical ecommerce site may have dozens of ways to handle different payment methods, shipping options, and return policies. In these situations, it is often useful to implement a system of toggles so that the system can be configured to handle each type of customer.
Another use of toggles is in multivariate or A/B testing. A website may want to know whether a certain feature will be more effective in encouraging users to make a purchase or click a call-to-action button. To do this, the system can add an experiment toggle that will consistently send a given user down one of two codepaths. After some time, the company can then analyze the data to see which codepath performs better and implement that version of the website for all users.
Toggles can also be used to support agile development processes. In more traditional waterfall development models new features are written on separate code branches and then integrated back into trunk code. With toggles, teams can develop and test new features on their own branches without affecting the existing live application. This can help shorten the deployment cycle and allow your team to respond quickly to latency problems and other issues.
Lastly, feature toggles can be used to support accessibility by allowing developers to configure the software to ignore specific user input such as red/green color vision deficiency. By default, most browsers interpret green as “on” and red as “off” – making toggles inaccessible to people with this condition. This is an important consideration for any product that will be used by people with disabilities.
It is important to note that while it is wise to test the toggle configuration that will be released into production it is equally important to test the fallback or “off” configuration of those toggles as well. This will help prevent surprise regressions that could occur if the wrong toggle configuration were accidentally pushed into production.
It is also important to remember that a release toggle is intended to be transitionary in nature, although it may need to remain in place for longer than other product-centric features. In most cases, it is not a good idea to leave a toggle in place for more than a week or two, even though the decision to keep it on or off may be very static.
