This script performs the buildpack transformation. BUILD_DIR will be the location of the app and CACHE_DIR will be a location the buildpack can use to cache build artifacts between builds. All output received on stdout from this script will be displayed to the user (for interactive git-push builds) and stored with the build. The application in BUILD_DIR along with all changes made by the compile s
![Buildpack API | Heroku Dev Center](https://cdn-ak-scissors.b.st-hatena.com/image/square/a1b2a24fb8bb6b5daa830ba9854ce4ba0af7b021/height=288;version=1;width=512/https%3A%2F%2Fwww.herokucdn.com%2Fimages%2Fog.png)