anchor.diff:              id: my-org/my-plugin
     ``` 
   
  -Another tool available to help test your plugin is the [Plugin Tester](https://github.com/buildkite-plugins/plugin-tester) Docker image. 
  -  - includes BATS (bash automated testing system) for writing tests
  -  - write tests in BATS and run them inside the container
  -  - test code example
  -
   ## Tools
   
   The following are some helpful tools when developing plugins:
  
positive.code: 
  For example `image: "node"` becomes the environment variable `BUILDKITE_PLUGIN_DOCKER_IMAGE="node"`, and `links: [ "db", "redis" ]` becomes the enviroment variables `BUILDKITE_PLUGIN_DOCKER_LINKS_0="db"` and `BUILDKITE_PLUGIN_DOCKER_LINKS_1="redis"`.
  
  ## Testing your new plugin
  
  The [Buildkite CLI](https://github.com/buildkite/cli) can be used to run your pipeline steps locally.
    - useful for testing your plugin
    - requires `buildkite-agent` locally as well
    - run your pipeline with `bk local run`
    - code example
  
  A [linter](https://github.com/buildkite-plugins/buildkite-plugin-linter)  is also available to check your new plugin against the latest best practices.
    - can be run locally, or included in a docker-compose file
  
negative.code: # Developing plugins
  
  The best place to get started is the [Buildkite Plugins] repository. You can also find third-party plugins with the [buildkite-plugin tag on GitHub][third party plugins]. This guide will walk through how to write a plugin and how to test your plugin step by step.
  
  ## Writing a plugin
  
  Plugins are essentially a collection of hooks with extra configuration. The agent passes the plugin configuration from the pipeline.yml to the plugin hooks as environment variables.
  
  