before_script:
  # Install ssh-agent if not already installed, it is required by Docker.
  - 'which ssh-agent || ( apt-get update -y && apt-get install openssh-client -y )'
  # Run ssh-agent (inside the build environment)
  - eval $(ssh-agent -s)
  # Add the SSH key stored in SSH_PRIVATE_KEY variable to the agent store
  - ssh-add <(echo "$SSH_PRIVATE_KEY")
  # For Docker builds disable host key checking. Be aware that by adding that
  # you are suspectible to man-in-the-middle attacks.
  # WARNING: Use this only with the Docker executor, if you use it with shell
  # you will overwrite your user's SSH config.
  - mkdir -p ~/.ssh
  - '[[ -f /.dockerenv ]] && echo -e "Host *\n\tStrictHostKeyChecking no\n\n" > ~/.ssh/config'