DuckRails now has its own docker image and so you can run the application without having to setup anything related to databases, secret keys etc. https://hub.docker.com/r/iridakos/duckrails/
Usage
You can now use:
docker pull iridakos/duckrails
to download the image and then you can start the application with:
docker run -p <port>:80 iridakos/duckrails
(replace <port> with the port you want to access the application locally).
Test that everything works as expected by navigating to
http://localhost:<port>
You should be seeing the DuckRails home page!

For a detailed guide, check the repository’s wiki page.
Note
This was my first attempt to create a docker image so if you have any notes/improvements, you are more than welcomed to contribute. The Dockerfile is located at the root folder of the DuckRails repo.
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