Release phase (public beta): run any command before a new release is deployed

Change effective on 02 June 2016

By declaring a release process type in your Procfile, you can run any command before a new release is deployed to your app’s dyno formation. Use release phase to migrate a database schema, invalidate a cache, upload static assets to a CDN, and more.

Release phase is available in public beta, with more information in the release phase documentation.