The recommended way to use this Docker image is to go to the directory where you have your Emerald code (and not much else!), and run the following command:

docker run \
  --interactive --tty --rm \
  --volume "$(pwd):/home/docker/src/" \
  --workdir "/home/docker/src/" \
  portoleks/mechanicalsoup

To gracefully exit from the Docker image, type exit or press Ctrl+D.

Please remember that when you exit, everything done outside the virtual /home/docker/src/ directory will be lost. At the same time, whatever happens in /home/docker/src/ will be reflected in the directory from where you ran the above command.