Toggle is a term used to describe a switch or button that allows you to change between two different states or options. It is commonly found in everyday technology devices such as phones or computers. However, it is also used in programming and development as a way to describe how code can be turned on or off, or how different functions are enabled or disabled.
When a team creates new functionality they can put it behind a feature toggle to test how it will be received by users in a real-world environment. This can be particularly helpful when testing a redesign of a product’s user interface. Toggle also allow engineers to rollback features that may cause unexpected issues with production.
Feature toggles can also be useful in continuous deployment by acting as circuit breakers. By making it easy to turn off components during high latency periods it’s easier to maintain and recover from performance problems.
Toggles are also useful for enabling A/B tests and multivariate experiments. For example, an e-commerce company may want to test which of two different suggestion algorithms produces the best results with their customers. To do this they add an experiment toggle to their configurator and use it to bucket users into one of the two algorithm groups. After a few weeks of testing the engineering team decides that they have conclusive evidence that more users complete their orders with the B algorithm so they remove the experiment toggle and deploy the algorithm into production.
