anchor.diff:  git init
   ```
   
  -## Add a plugin.yml
  +### Add a plugin.yml
   
   Next we'll create the first file: a `plugin.yml` file. This describes how it will appear in the [Buildkite Plugin Directory](/docs/plugins/directory).
   
  
positive.code: docker-compose run --rm tests
  ```
  
  ## Add a readme
  
  Next we'll add a `README.md` file to introduce the plugin to the world:
  
  
negative.code: # Writing Plugins
  
  This page shows you how to write your own Buildkite plugin, and how to validate the `plugin.yml` file which describes it against the plugin schema.
  
  {:toc}
  
  ## Plugin tutorial
  
  In this tutorial we'll create a Buildkite plugin called "File Counter", which counts the number of files in the build directory once the command has finished, and creates a build annotation with the count.
  
  