anchor.diff:    - label: ':hammer: Tests'
       command: 'scripts/tests.sh'
       plugins:
  -      docker-compose#v1.7.0:
  +      docker-compose#v1.8.4:
           run: app
   ```
   
  
positive.code: ## What's changed
  
  * [Plugins](/docs/agent/v3/plugins) for easily sharing functionality between pipelines and customizing how agents behave
  * The bootstrap (run as a sub-process for every job) has moved from a [shell script](https://github.com/buildkite/agent/blob/2-6-stable/templates/bootstrap.sh) to a sub-command of the `buildkite-agent bootstrap`. This means it's written in golang and cross-platform.
  * Agent meta-data has been renamed to "tags"
  * Built-in [Docker and Docker Compose support](/docs/builds/docker-containerized-builds) has been deprecated and moved to dedicated plugins, [docker-compose](https://github.com/buildkite-plugins/docker-compose-buildkite-plugin) and [docker](https://github.com/buildkite-plugins/docker-buildkite-plugin).
  * Variable interpolation in pipeline.yml
  * Much better Windows support, including .BAT hooks support
  * Build annotations
  * Default flags for `git clean` include `-x`
  
  ## Bootstrap customizations
  
  
negative.code: 
  Previously we didn't support variable interpolation like `${MY_VARIABLE_NAME}` or `$MY_VARIABLE_NAME`, so if you have any of these in your previous pipeline's and expect the literal text to render, you will need to escape the dollar signs like `$$MY_VARIABLE_NAME`.
  
  ### Checkout cleans giles in `.gitignore`
  
  Older agents didn't remove files from your working directory that were ignored by git. The new default values for git clean are `-fxdq`. If you've previously overridden your `git-clean-flags` in your config, it might be a good chance to comment them out and use the standard behaviour.
  
  ## Upgrading from a 2.0 agent
  
  To upgrade you simply install the a new 3.0 agent using the [standard installation methods](installation). You can use agent tags to create a new queue for 3.0 builds so that you can test it in parallel to your existing agents.
  
  To make installation easy we’ve created packages for each of the major operating systems.
  
  ## Upgrading from beta of a 3.0 agent
  
  To upgrade a _Ubuntu / Debian_ 3.0 beta agent:
  
  