heroku.yml build manifest is now available (developer preview)

Change effective on 29 November 2017

heroku.yml is a new manifest for defining your app’s build, allowing you to:

  • Easily add packages to your application from apt
  • Define commands that you would like to run pre and post compilation
  • Take advantage of Review Apps when deploying Docker-based applications
  • Build your Docker images on Heroku

heroku.yml currently supports building Ruby, Java, and Docker-based apps. To get started, check out the heroku.yml Dev Center documentation.