A toggle is a simple user-interface component that lets users update preferences, settings, and other types of information. Toggles provide direct labels, use standard visual design, and deliver immediate results. They’re also a great tool for testing new code and features in the wild with targeted audiences. To make the most of toggles, consider keeping their inventory low and implementing a process for cleaning them up as soon as they’ve run their course.
The term “toggle” has been around for centuries, but the modern definition of the word is a simple on-off switch. It’s used in a variety of applications, from the toggle on your caps lock key to a toggle fastener. Similarly, in software development, toggles are simple on-off switches that control a larger piece of software. In the early days of computer technology, toggles were often created as binary switches.
More recently, however, software developers have been using toggles to control more complicated pieces of functionality. These are known as feature toggles. In contrast to a binary switch, which controls one output at a time, feature toggles can control many different outcomes simultaneously. The most common use for a toggle is to test a new feature before deploying it to all users. By changing the toggle state to ON, an engineering team can deploy a feature to a subset of users and track how the feature performs in a real-world environment. If the toggle is switched OFF, the engineering team can roll back to a previous version of the software.
Toggles are useful for testing new software in the wild, but they can cause performance issues if not managed correctly. It’s best to keep the number of toggles in production low, and to deploy a software release only when all of its toggles are turned ON. This helps to avoid unnecessary database calls that could potentially impact read performance in production environments.
When a feature toggle is configured to ON, the platform will query an outside source (such as a data warehouse or service like Kameleoon) to check its state. If the toggle is ON, the platform will execute its function; if it’s OFF, the platform will skip the function. This allows teams to toggle features ON and OFF without having to alter their source code or deploy new releases. In this way, feature toggles support agile development processes by allowing dev teams to release features before they’re complete. In more traditional waterfall development models, these features would need to go through a lengthy QA and testing process before they were ready for production. Ultimately, this can save valuable time and resources.
