Toggle is a simple, powerful control that allows you to disable or enable functionality. You can use toggles for a variety of purposes, including hiding features that you’re still testing or that aren’t ready for public release. Toggles are also useful for debugging and performing localized changes to the user experience.

The most common way to implement a feature toggle is using static files to manage their configuration. This is a good solution at small scale, but it becomes unwieldy once you start growing the size of your toggle configurations. It’s often easier to implement a dedicated centralized toggle management system, which usually involves leveraging an existing application database for storing and managing toggle configurations. This typically involves creating some form of admin UI that can be used by system operators, testers and product managers to view and modify the state of the feature flags in your system.

It is important to use toggles sparingly, and only to change the state of a single feature at a time. This reduces the amount of complexity and dependencies that your codebase needs to deal with, which can make debugging bugs much easier. Changing multiple toggles at once can be confusing for everyone involved, and can cause unexpected behavior that could confuse users or impact other teams.

When implementing a feature toggle, it’s recommended to name the toggle something descriptive. This helps other developers quickly identify the purpose of a toggle and its intended state. It also makes debugging error messages easier for everyone involved, since it gives a context for what might be wrong.

It can be tempting to create a toggle for every bug fix you encounter. However, this can be very risky and it’s often better to make a case-by-case decision about whether to create a toggle or not. If you decide to create a toggle, be sure to test the entire toggle configuration that you expect to live in production. That includes any toggles that you intend to release flipped On as well as any that you’re planning to release flipped Off. This practice helps ensure that any fixes won’t accidentally worsen the behavior of the system.

Experiment Toggles

A commonly used technique for multivariate or A/B testing is to create an experiment toggle that splits users into different cohorts. Then at runtime the toggle router can consistently send each user down one of two codepaths, and you can track which path is more effective.

Toggle switches are an excellent choice for ecommerce configurators, where you want to give users the option to select between several variants of the same feature. This allows you to easily change the appearance of the configurator without changing the underlying logic behind it. This is especially helpful when your users have different color preferences for the same feature. Use high contrast colors for your toggle switches, and utilize visual cues to indicate their current state. For example, you might use a tick and cross icon that morphs into the actual switch state for extra clarity.