## (Backward Compatibility Break) Docker no longer installed by default
The playbook used to install Docker and the Docker SDK for Python by default, unless you turned these off by setting `mash_playbook_docker_installation_enabled` and `devture_docker_sdk_for_python_installation_enabled` (respectively) to `false`.
From now on, both of these variables default to `false`. An empty inventory file will not install these components.
**Most** users will want to enable these, just like they would want to enable [Traefik](docs/services/traefik.md) and [Postgres](docs/services/postgres.md), so why default them to `false`? The answer is: it's cleaner to have "**everything** is off by default - enable as you wish" and just need to add stuff, as opposed to "**some** things are on, **some** are off - toggle as you wish".
To enable these components, you need to explicitly add something like this to your `vars.yml` file:
