This is our first minor release in almost a year. Many new features and removals have occurred, so here is a neat summary:

• Plugins are now triggered via plugn. Notably, you'll need add a plugin.toml to describe the plugin as well as use plugn trigger instead of pluginhook to trigger plugin callbacks. Please see the plugin creation documentation for more details.
• A few new official plugins have been added to the core, including image tagging, certificate management, a tar-based deploy solution, and much more. Check out the New Features section for more details.
• We've removed a few deprecated plugin callbacks. Please see the plugin triggers documentation to see what is available.
• Official datastorage plugins have been created for the most commonly used datastores. If you previously used/maintained a community contributed plugin, please check these out. We'll be adding more official plugins as time goes on.

If you are coming from a previous release, please run the following command to install the latest docker version first (otherwise you will be pegged to docker 1.6.2):

curl -sSL https://get.docker.com/ | sh

Thanks to the many contributors for making this release our best release so far, and special thanks to both @michaelshobbs and @Flink for pushing along the 0.4.0 release!

Install via the bootstrap script:

wget https://raw.githubusercontent.com/dokku/dokku/v0.4.0/bootstrap.sh
sudo DOKKU_TAG=v0.4.0 bash bootstrap.sh

Deprecations and Removals

• #1372: @SonicHedgehog Do no longer force-install a default nginx.conf
• #1415: @tilgovi Remove uses of (un)set-norestart
• #1432: @josegonzalez Delete unmaintained AUTHORS file
• #1450: @michaelshobbs Rename event plugin buildstep hooks to buildpack

Bug Fixes

• #1344: @AdamVig Add better error checking on nginx:import-ssl
• #1417: @josegonzalez Expose host and port in vagrant build vm
• #1418: @josegonzalez Use cgroupfs-mount as alternative package to cgroup-lite dependency
• #1419: @u2mejc Fix dokku ps over ssh
• #1422: @josegonzalez Guard against missing VHOST files when listing domains
• #1428: @jimeh Use $PLUGIN_PATH instead of $(dirname $0)/..
• #1430: @lubert Update vagrant box name to bento/ubuntu-14.04
• #1439: @michaelshobbs Fix tar tests by sleeping for 5 seconds
• #1447: @alanjds Properly detect app name in the official cli client
• #1449: @josegonzalez Match herokuish deb with released version number
• #1457: @lukechilds Bashstyle fixes
• #1463: @josegonzalez Update Xenify Distro option for linode stackscript
• #1464: @josegonzalez Limit number of log lines when calling dokku logs -t
• #1466: @josegonzalez Follow bashstyle conventions where possible
• #1471: @michaelshobbs Make the default scaling logic clearer
• #1475: @josegonzalez Fix issue where restart on failure option overrode existing DOCKER_ARGS

New features

• #1225: @michaelshobbs Add tags plugin to handle image tagging and deployment of tagged app images
• #1228: @michaelshobbs Use plugn instead of pluginhook to trigger plugin hooks
• #1402: @josegonzalez Consolidate configuration management into config plugin
• #1414: @michaelshobbs Add certs plugin for certificate management
• #1420: @josegonzalez Add dokku enter for connecting to an app container
• #1421: @basicer Add tar plugin to manage tar-based deployments
• #1423: @josegonzalez Set DYNO_TYPE_NUMBER environment variable for each container
• #1431: @josegonzalez Add helper function for inspecting the state of a container
• #1444: @josegonzalez Extract cleanup command into common function
• #1445: @josegonzalez Create CONTRIBUTING.md
• #1455: @michaelshobbs Continue and log an event if/when container retirement fails
• #1458: @michaelshobbs Set Herokuish TRACE=true when DOKKU_TRACE is set
• #1460: @michaelshobbs Bump herokuish version to 0.3.3
• #1465: @josegonzalez Set DYNO environment variable to heroku-compatible value
• #1467: @josegonzalez Upgrade dokku installation to use docker-engine
• #1468: @michaelshobbs Clean up semver logic and run install-dependencies after package installation
• #1469: @isundaylee Add nginx:access-logs and nginx:error-logs commands
• #1470: @assaf Add nginx configuration for running behind load balancer
• #1472: @michaelshobbs Use processes defined in Procfile when generating DOKKU_SCALE file
• #1473: @josegonzalez Handle crashing containers by using restart=on-failure policy
• #1476: @michaelshobbs Support static nginx port when deploying without an application VHOST
• #1476: nginx proxy without VHOST
• #1477: @arthurschreiber Support removing config variables that contain \n.

Documentation

• #1407: @ertrzyiks Correct DOKKU_DOCKERFILE_PORT variable name in docs
• #1408: @josegonzalez Add links to official dokku datastorage plugins
• #1426: @henrik Update memcached link to maintained fork
• #1437: @Flink Update compatibility version for several plugins
• #1446: @johnfraney Correct nginx documentation
• #1478: @eljojo Fix naming of herokuish package in installation docs