Package packit provides primitives for implementing a Cloud Native Buildpack according to the specification: https://github.com/buildpacks/spec/blob/master/buildpack.md. According to the specification, the buildpack interface is composed of both a detect and build phase. Each of these phases has a corresponding set of packit primitives enable developers to easily implement a buildpack. The purpose of the detect phase is for buildpacks to declare dependencies that are provided or required for the buildpack to execute. Implementing the detect phase can be achieved by calling the Detect function and providing a DetectFunc callback to be invoked during that phase. Below is an example of a simple detect phase that provides the "yarn" dependency and requires the "node" dependency. The purpose of the build phase is to perform the operation of providing whatever dependencies were declared in the detect phase for the given application code. Implementing the build phase can be achieved by calling the Build function and providing a BuildFunc callback to be invoked during that phase. Below is an example that adds "yarn" as a dependency to the application source code. These examples show the very basics of what a buildpack implementation using packit might entail. For more details, please consult the documentation of the types and functions declared herein.