CLIs are a fantastic way to build products. Unlike web applications, they take a small fraction of the time to build and are much more powerful. With the web, you can do whatever the developer programmed. With CLIs, you can easily mash-up multiple tools together yourself to perform advanced tasks. They require more technical expertise to use, but still work well for admin tasks, power-user tasks, or developer products.

At Heroku, we’ve come up with a methodology called the 12 factor app. It’s a set of principles designed to make great web applications that are easy to maintain. In that spirit, here are 12 CLI factors to keep in mind when building your next CLI application. Following these principles will offer CLI UX that users will love.

We’ve also built a CLI framework called oclif that is designed to follow these principles to build great CLIs in Node.