anchor.diff:  
   * **Updating, renaming, or deleting a uniquely-named buildpack:**
   	* You have a single buildpack named `my-buildpack`, and it is associated with `stack_a`.  If you want to delete the buildpack, you can run `cf delete-buildpack my-buildpack`.<br><br>
  -	You can also provide -`s stack_a` but the option is not required if you have a uniquely-named buildpack.
  +	You can also provide `-s stack_a`, but the option is not required if you have a uniquely-named buildpack.
   * **Updating, renaming, or deleting a uniquely-named buildpack that has a `nil` stack:**
   	* You have a single buildpack named `my-buildpack`, and it is not associated with a stack.  If you want to delete the buildpack, you can run `cf delete-buildpack my-buildpack`.
   * **Updating, renaming, or deleting a buildpack when another buildpack exists with the same name, and both buildpacks have stack associations:**
  -	* You have two buildpacks named `my-buildpack`, one that associated with `stack_a` and the other associated with `stack_b`. If you want to delete the buildpack that uses `stack_a`, you can run `cf delete-buildpack my-buildpack -s stack_a`.
  +	* You have two buildpacks named `my-buildpack`, one that is associated with `stack_a` and the other associated with `stack_b`. If you want to delete the buildpack that uses `stack_a`, you can run `cf delete-buildpack my-buildpack -s stack_a`.
   * **Updating, renaming, or deleting a buildpack when another buildpack exists with the same name. One buildpack has a stack association, and the other buildpack has a `nil` stack:** 
   	* You have two buildpacks named `my-buildpack`, one associated with  `stack_a` and the other associated with no (`nil`) stack association:
   		* If you want to delete the buildpack that uses `stack_a`, you can run `cf delete-buildpack my-buildpack -s stack_a`. 
  
positive.code: owner: Buildpacks
  ---
  
  This topic describes the stack association feature for Cloud Foundry buildpacks. 
  
  <p class="note"><strong>Note</strong>: This functionality is supported as of CAPI <a href="https://github.com/cloudfoundry/capi-release/releases/tag/1.58.0">v1.58.0</a> and <a href="https://github.com/cloudfoundry/cli/releases/tag/v6.39.0">cf CLI v6.39.0</a>.</p>
  
  <p class="note warning"><strong>WARNING</strong>: To avoid security exposure, ensure that you migrate your apps and custom buildpacks to use the <code>cflinuxfs3</code> stack based on Ubuntu 18.04 (Bionic Beaver). <code>cflinuxfs2</code> is based on Ubuntu 14.04 (Trusty Tahr), which reaches end of general support (EOGS) in April 2019. </p>
  
  ## <a id='overview'></a> Overview ##
  
  Each buildpack in your Cloud Foundry deployment is associated with a stack. You can see this when you run `cf buildpacks`: there is a `stack` column in the output that shows a corresponding stack for each buildpack. See the following example: 
  
  <pre class="terminal">
  $ cf buildpacks
  
negative.code: 
  Because of this stack association, buildpacks do not have to be uniquely named. This helps in managing similar buildpacks that are compatible with different stacks. 
  
  The [buildpack packager](https://github.com/cloudfoundry/libbuildpack/tree/master/packager) includes a `-stack` option. If you use this option and upload a buildpack to <%= vars.product_name %>, the Cloud Controller detects the stack association and creates a stack record for the buildpack. 
  
  ## <a id='no-stack-record'></a> Buildpacks without a Stack Record ##
  
  Some buildpacks may have a missing stack record. For example, if you uploaded a custom buildpack before <%= vars.product_name %> introduced stack assocation. The output of `cf buildpacks` shows a blank `stack` column if the buildpack does not have a stack record. 
  
  In this case, you must manually assign a stack to the buildpack. To do this, run `cf update-buildpack BUILDPACK-NAME -p PATH/TO/BUILDPACK`, where the path contains a `manifest.yml` with a stack as a top level property. See [Creating Custom Buildpacks](./custom.html) for more information. 
  
  