Dockerized applications can still reach services on the localhost, but you may want to take a look at docker compose so you get your application and backing systems in one place.
It makes your local development environment incredibly resilient.
Do you have an example how that would work? I unsuccessfully spent quite a while trying to get a docker container running rails to talk to a docker container running postgre. And I wanted to postgre container to persist to the host's disk so I could save state between runs. Maybe that wasn't the best way to do it though?
It makes your local development environment incredibly resilient.