-   `docker-compose up`, and `docker-compose start` will now start containers
    in parallel where possible.

-   `docker-compose stop` now stops containers in reverse dependency order
    instead of all at once.

-   Added the `--build` flag to `docker-compose up` to force it to build a new
    image. It now shows a warning if an image is automatically built when the
    flag is not used.

-   Added the `docker-compose exec` command for executing a process in a running
    container.


### Bug fixes

-   `docker-compose down` now removes containers created by
    `docker-compose run`.

-   A more appropriate error is shown when a timeout is hit during `up` when
    using a tty.

-   Fixed a bug in `docker-compose down` where it would abort if some resources
    had already been removed.

-   Fixed a bug where changes to network aliases would not trigger a service
    to be recreated.

-   Fix a bug where a log message was printed about creating a new volume
    when it already existed.

-   Fixed a bug where interrupting `up` would not always shut down containers.

-   Fixed a bug where `log_opt` and `log_driver` were not properly carried over
    when extending services in the v1 Compose file format.

-   Fixed a bug where empty values for build args would cause file validation
    to fail.

## 1.6.2

(2016-02-23)

-   Fixed a bug where connecting to a TLS-enabled Docker Engine would fail with
    a certificate verification error.

## 1.6.1

(2016-02-23)

### Bug fixes

-   Fixed a bug where recreating a container multiple times would cause the
    new container to be started without the previous volumes.

-   Fixed a bug where Compose would set the value of unset environment variables
    to an empty string, instead of a key without a value.

-   Provide a better error message when Compose requires a more recent version
    of the Docker API.

-   Add a missing config field `network.aliases` which allows setting a network
    scoped alias for a service.

-   Fixed a bug where `run` would not start services listed in `depends_on`.

-   Fixed a bug where `networks` and `network_mode` where not merged when using
    extends or multiple Compose files.

-   Fixed a bug with service aliases where the short container id alias was
    only contained 10 characters, instead of the 12 characters used in previous
    versions.

-   Added a missing log message when creating a new named volume.

-   Fixed a bug where `build.args` was not merged when using `extends` or
    multiple Compose files.

-   Fixed some bugs with config validation when null values or incorrect types
    were used instead of a mapping.

-   Fixed a bug where a `build` section without a `context` would show a stack
    trace instead of a helpful validation message.

-   Improved compatibility with swarm by only setting a container affinity to
    the previous instance of a services' container when the service uses an
    anonymous container volume. Previously the affinity was always set on all
    containers.

-   Fixed the validation of some `driver_opts` would cause an error if a number
    was used instead of a string.

-   Some improvements to the `run.sh` script used by the Compose container install
    option.

-   Fixed a bug with `up --abort-on-container-exit` where Compose would exit,
    but would not stop other containers.

-   Corrected the warning message that is printed when a boolean value is used
    as a value in a mapping.

## 1.6.0

(2016-01-15)

### Major Features

-   Compose 1.6 introduces a new format for `docker-compose.yml` which lets
    you define networks and volumes in the Compose file as well as services. It
    also makes a few changes to the structure of some configuration options.

    You don't have to use it - your existing Compose files will run on Compose
    1.6 exactly as they do today.

    Check the [upgrade guide](/reference/compose-file/legacy-versions.md)
    for full details.

-   Support for networking has exited experimental status and is the recommended