anchor.diff:  
   Example: `HOME=/home/vcap/app`
   
  +### <a id='LANG'></a>LANG ###
  +LANG is required by buildpacks to ensure consistent script load order.
  +
  +Example: `LANG=en_US.UTF-8`
  +
   ### <a id='memory'></a>MEMORY_LIMIT ###
   The maximum amount of memory that each instance of the application can consume.
   You specify this value in an application manifest or with the cf CLI when
  
positive.code:   </tr>
    <tr>
      <td><code>instance_id</code></td>
      <td>Unique ID that identifies the application instance. For instances running on Diego, this is identical to the <a href="#CF-INSTANCE-GUID">CF_INSTANCE_GUID</a> variable.</td>
    </tr>
    <tr>
      <td><code>instance_index</code></td>
  
negative.code: ### <a id='CF-INSTANCE-PORT'></a>CF\_INSTANCE\_PORT ###
  
  The external, or *host-side*, port corresponding to the internal, or *container-side*, port with value [PORT](#PORT).
  This value is generally different from the
  [PORT](#PORT) of the app instance.
  
  Example: `CF_INSTANCE_PORT=61045`
  