Fuller "getting started" example with postgres/redis env vars/lifecycle?

Is there a slightly more complete example of running a Rails app on Waypoint that includes referring to postgres and redis?

I’m moving a bunch of our stuff off of Heroku. (It’s actually Clojure instead of Rails, but Rails is a generic enough substrate that it would answer some questions for me). Ultimately our goal is to set up a Nomad cluster with Vault/Consul on Digital Ocean. For now, though, I’m hoping I can understand things via the Docker build/deploy on my laptop.

Particular questions I have:

  • Is it assumed that my postgres db has been initially created outside of the waypoint build?
  • How could a particular app instance know about the DATABASE_URL or REDIS_URL here and run migrations? Is this where Consul comes in?

(I’m very new with Waypoint so apologies if these questions “aren’t even wrong”. I’m looking for stepping stones for us to go from our current Heroku setup with Java uberjars to Docker containers to a Nomad cluster, so that we can just take the first step of dockerizing and slowly learn and build).