anchor.diff:  * Logs helpful warning and error messages if it detects compatibility issues with your application that require manual migration
   * Change the default web server back to Apache HTTPD. For those migrating from the previous buildpack, this will be the expected
   
  +<p class="note"><strong>WARNING:</strong> When migrating from `options.json` to `buildpack.yml`, you cannot have both files present. The Compat CNB will still run, showing what still needs to be migrated, but it will error because it cannot merge the two files.</p>
  +
   ## <a id='migrations'></a> Manual Migrations ##
   
   Depending on your application, you may need to make some manual migrations. The following migrations cannot be done by the Compat CNB, so they require manual configuration.
  +
  +<p class="note"><strong>Note:</strong> The following sections use a dot notation to reference configuration options from buildpack.yml. This should be expanded into valid YAML syntax. See <a href="php-config.html#options">the buildpack.yml configuration options section for details</a>.</p>
   
   ### <a id='buildpack_extensions'></a> Buildpack Extensions ###
   
  
positive.code: 
  2. In `buildpack.yml`, set `php.web_directory` to point to an existing directory where you store your public files.
  
  ### <a id='composer_vendor_dir'></a> Application Files No Longer Moved ###
  
  There have been a couple changes with respect to Composer's handing of the `vendor` directory.
  
  1. The previous buildpack would put Composer's `vendor` directory on PHP's `include_path` by default. Users reported this as unexpected and adding additional directories to the `include_path` can slow down PHP, so this behavior was changed.
  
      If you would like to have the `vendor` directory on the `include_path` then you can set `php.libdirectory` in `buildpack.yml` to the location of your `vendor` directory. The `php.libdirectory` is added to the `include_path` by default, so this will cause your `vendor` directory to be on the `include_path`.
  
      Alternatively, you could include a `php.ini` snippet that adjusts the `include_path` directly, but you need to be very careful as this will completely override the default set by the buildpack.
  
  2. Composer's `vendor` directory is no longer moved. Previously, it was moved into the `php.libdirectory`. Moving this folder broke some apps which expected the vendor directory to be in a specific location. As such, we no longer move the `vendor` directory. It will exist where you put it. If you need it in a specific place, just locate it there.
  
  3. Composer now defaults the `vendor` directory to be under the application root instead of the `php.libdirectory`. This change was made because it is inline with the default behavior we see with frameworks like Cake & Symfony, so more applications will "just work" without additional configuration required.
  
      If you prefer the old behavior, you can change it back by setting `composer.vendor_directory` in `buildpack.yml` to point to a location under the `php.libdirectory` folder.
  
  
negative.code:       * is now expected under the application root by default, not under the library directory
    * The files `composer.json`, `composer.lock` and/or `auth.json` are no longer moved. This caused confusion.  If you need them in a specific location, put them there prior to pushing your code. You can also set `composer.json_path` to adjust where the buildpack finds these files. Lastly, if you leave the in a public directory, the buildpack will emit a warning as this isn't safe.
    * You can no longer set `COMPOSER_BIN_DIR` or `COMPOSER_CACHE_DIR`. They are automatically set by the CNB such that `COMPOSER_BIN_DIR` will be on the `PATH` and such that files will be correctly cached to reduce downloads and speed up builds.
  * The default web server used by the PHP Cloud-Native Buildpack is PHP's built-in web server. This is lighter weight and produces smaller images. When running on Cloud Foundry, this option is not used because of the PHP Compat CNB, see next section for details.
  
  ## <a id='compat_cnb'></a> PHP Compat Cloud-Native Buildpack ##
  
  