Follow up with the previous link, if I want to run system test cases in Rails using:

class ApplicationSystemTestCase < ActionDispatch::SystemTestCase
  driven_by :selenium, using: :headless_firefox, screen_size: [1400, 1400]
end

Then I need to install Firefox, as well as fonts, so that the screenshots are rendered properly.

apk add xvfb firefox ttf-dejavu

(note: fonts are required for Firefox to render pages)

A great article for using docker-compose as a dev environment for rails

Learning lxc

Go through this to learn more about Docker Compose

Interesting write-up. The #1 quote for me is:

And as near as I can tell, this is 100% why Docker is winning. Forget all the nonsense you read about Docker making deployment or security or orchestration easier. It doesn’t. But it is emerging as a standard, something a person can learn at one company and then take to another company. It isn’t messy and ad-hoc the way a custom bash script would be. And that is the real argument in favor of Docker. Whether it can live up to that promise is the gamble.

Good tutorial about Docker