--- title: inject --- The `inject` key in the pattern configuration file allow you to configure the rules for injecting one part into another. By _injecting_ we mean that rather than starting out with a fresh part, you'll get a part that has the points, paths, and snippets of the injected part. ## Structure A plain object of key/value pairs of parts. The `value` part will be injected in the `key` part. ## Example ```js inject: { front: "back" } ``` In this example, the `back` part will be injected in the `front` part. In doing so, the `front` part will start out as a copy of the `back` part. See [the Howto on Part inheritance](/howtos/code/inject) for a hands-on example.