gistfile1.txt

Ensure salt virtualenv exists:
  virtualenv.managed:
    - name: /srv/salt/venv
    # Switch to the existing salt venv
    - pip_exists_action: s
    - system_site_packages: True
    - requirements: /my/requirements.txt

Ensure modules and grains are refreshed if salt venv changes:
  module.wait:
    - name: saltutil.refresh_modules
    # This needs to happen immediately, so we use watch, rather than listen.
    - watch:
      - virtualenv: Ensure salt virtualenv exists