anchor.diff:  
   ## 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 upgrade, install the new 3.0 agent using one of the [standard installation methods](installation). To make installation easier, there are packages for each of the major operating systems.
   
  -To make installation easy we’ve created packages for each of the major operating systems.
  +You can test your updated agents in parallel to your existing agents by using agent tags to create a new queue for 3.0 builds.
   
   ## Upgrading from 3.0-beta to a stable 3.0 agent
   
  
positive.code:       BUILDKITE_DOCKER_COMPOSE_CONTAINER: app
  ```
  
  To convert it to the [docker-compose plugin](https://github.com/buildkite-plugins/docker-compose-buildkite-plugin)
  you would do this:
  
  ```yaml
  steps:
  
negative.code: 
  <%= toc %>
  
  ## Overview of what has changed
  
  Added:
  
  * [Plugins](/docs/agent/v3/plugins) for easily sharing functionality between pipelines and customizing how agents behave
  * [Variable interpolation](cli_pipeline) in `pipeline.yml`
  * [Build annotations](cli_annotate)
  
  Changed:
  
  * Agent meta-data has been renamed to "tags"
  * Much better Windows support, including .BAT hooks support
  * Checkout clean no longer ignores files in `.gitignore`
  * 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 [`buildkite-agent bootstrap`](cli_bootstrap). This means it's written in golang and cross-platform.
  
  Deprecated:
  
  * Built-in [Docker and Docker Compose support](/docs/builds/docker-containerized-builds) has been deprecated. The same functionality is available from the dedicated plugins: [docker-compose](https://github.com/buildkite-plugins/docker-compose-buildkite-plugin) and [docker](https://github.com/buildkite-plugins/docker-buildkite-plugin).
  
  ## Bootstrap customizations
  
  If you customized your `bootstrap.sh` file, you will need to move the changes to [hooks](hooks), or update your bootstrap.sh to call `buildkite-agent bootstrap`.
  
  ## Docker and Docker Compose support
  
  