anchor.diff:  Each plan can specify lifecycle event handlers, or hooks, to perform certain actions during a service's runtime. Each hook is a script with a [shebang](https://en.wikipedia.org/wiki/Shebang_(Unix)) defined at the top to specify the interpreter to be used. On Windows, Powershell Core is the only interpreter ever used.
   
   To define a hook, simply create a bash file of the same name in `/my_plan_name/hooks/`, for example, `/postgresql/hooks/health-check`.
  +
  +When applying a new configuration, modification to the `run` or `post-run` hooks will restart the service.
   
   > **Important** You cannot block the thread in a hook unless it is in the `run` hook. Never call `hab` or `sleep` in a hook that is not the `run` hook.
   
  
positive.code: * [health-check](#health-check)
  * [init](#init)
  * [install](#install)
  * [reload](#reload)
  * [reconfigure](#reconfigure)
  * [suitability](#suitability)
  * [run](#run)
  
negative.code: ###health-check
  File location: `<plan>/hooks/health-check`
  
  This hook is run periodically on a configurable interval.
  
  The `health-check` script must return a valid exit code from the list below.
  
  