Phoenix, Postgres.app and the default user

on postgres and config

I decided to work through this great introductory Phoenix framework tutorial by Erik today. At the point of running the initial $ mix ecto.create command however, it bombed on me, with this little message:

** (Mix) The database for PhoenixApi.Repo couldn't be created, reason given: psql: FATAL:  role "postgres" does not exist

Turns out, there is a solution to fix it for this and all other such cases. Postgres.App, it seems, does not create the default postgres user on installation but rather uses the the default $USER. Most tutorials assume the initial default. To fix it, simply run the following:

/Applications/Postgres.app/Contents/Versions/9.*/bin/createuser -s postgres

More info here.