Hopping in this a little late, but I just created my first Elixir library and it handles encrypted secrets much like Rails! Let me know what you think: https://github.com/kieraneglin/encrypted_secrets_ex

Cool. I like the sound of that. I might have a go at doing it when I get some free time.

You need your configs at the run-time, so you could use env variables for this.
I can recommend confex

config :credentials, 
  username: {:system, "USERNAME", "dev_user"},
  password: {:system, "PASSWORD", "dev_user"}.
  aws: [secret_access_key: {:system, "AWS_SECRET_KEY", "1234567"}]

At startup of you App, just do

defmodule MyApp do
  use Application

  def start(_type, _args) do
    # Replace Application environment with resolved values
    Confex.resolve_env!(:credentials)

    # ...
  end
end

This way you will be able to access your configs via the usual
Application.get_env(:credentials, :username)

Hello everyone Rails 5.2 introduced a new feature called Credentials and I think that is a good feature for Phoenix (or elixir) sometimes we have a build server and prod server in build server we need environment variables to build a project with Distillery, the point is that’s not easy to change environment variables to each project pipeline and usually we use (puppet, chef, etc) for that things. I’ll be very happy if have a possibility to add the project credentials together with the project (encrypted). To learn more about credentials.

rails/rails#30067

I didn’t know about confex, seems very useful.