Connects any Heroku app to Fly.io network.
Add a new backend on https://app.fly.io/ if you haven't already. You'll need the auth token.
Add a buildpack to your app and configure it:
heroku buildpacks:add https://github.com/superfly/fly-heroku-buildpack
heroku config:set FLY_TOKEN=<TOKEN_FOR_YOUR_BACKEND>
Deploy your changes:
git push heroku master
Your Fly backend should now be proxying traffic to your Heroku app. You can use one of the *.shw.io preview links to test that.
Once your app is set-up on Fly, you can stop the ingress traffic to your dyno by changing the process name in the Procfile from web
to something else.
You can find more details at https://fly.io/docs