### Breaking changes
- `docker-compose up` now resets a service's scaling to its default value.
You can use the newly introduced `--scale` option to specify a custom
scale value
### New features
#### Compose file version 2.2
- Introduced version 2.2 of the `docker-compose.yml` specification. This
version requires to be used with Docker Engine 1.13.0 or above
- Added support for `init` in service definitions.
- Added support for `scale` in service definitions. The configuration's value
can be overridden using the `--scale` flag in `docker-compose up`.
Please note that the `scale` command is disabled for this file format
#### Compose file version 2.x
- Added support for `options` in the `ipam` section of network definitions
Compose is a tool for defining and running multi-container Docker applications.
With Compose, you use a Compose file to configure your application's services.
Then, using a single command, you create and start all the services from your
configuration.
