I tried running it, but on a normal postgres database, not used by a ruby on rails app. It failed because it assumes RoR security tables (users)? Also tried to

I tried running it, but on a normal postgres database, not used by a ruby on rails app. It failed because it assumes RoR security tables (users)? Also tried to run it in a separate docker image, next to a postgres docker, started from a shared docker-compose, but docs where unclear how to configure this (e.g., what environment variable is used to set the database name).