anchor.diff:  Include conf/extra/httpd-my-special-config.conf # This line includes your additional file.
   ```
   
  -
   #### <a id="php_ini_d"></a> .bp-config/php/php.ini.d/
   
  -The buildpack adds any `.bp-config/php/php.ini.d/FILE-NAME.ini` files it finds in the application to the PHP configuration. You can use this to change any value acceptable to `php.ini`. See [http://php.net/manual/en/ini.list.php](http://php.net/manual/en/ini.list.php) for a list of directives.
  +The buildpack adds any `.bp-config/php/php.ini.d/FILE-NAME.ini` files it finds in the app to the PHP configuration. You can use this to change any value acceptable to `php.ini`. For a list of directives, see [http://php.net/manual/en/ini.list.php](http://php.net/manual/en/ini.list.php).
   
  -For example, adding a file `.bp-config/php/php.ini.d/something.ini` to your app, with the following contents, overrides both the default charset and mimetype.
  +For example, adding a file `.bp-config/php/php.ini.d/something.ini` to your app, with the following contents, overrides both the default charset and mimetype:
   
   ```
   default_charset="UTF-8"
  
positive.code: zend_extension=opcache.so
  ``` 
  
  If an extension is already present and enabled in the compiled php, for example `intl`, you do not need to explicitly enable it to use that extension.
  
  #### PHP\_EXTENSIONS vs. ZEND\_EXTENSIONS
  
  PHP has two kinds of extensions, _PHP extensions_ and _Zend extensions_. These hook into the PHP executable in different ways. See [https://wiki.php.net/internals/extensions](https://wiki.php.net/internals/extensions) for more information about the way extensions work internally in the engine.
  
  Because they hook into the PHP executable in different ways, they are specified differently in ini files. Apps fail if a Zend extension is specified as a PHP extension, or a PHP extension is specified as a Zend extension.
  
  If you see the following error, move the `example` extension from `extension` to `zend_extension`, then re-push your app:
  
  ```
  php-fpm | [warn-ioncube] The example Loader is a Zend-Engine extension and not a module (pid 40)
  
negative.code: php-fpm | NOTICE: PHP message: PHP Fatal error:  Unable to start example Loader module in Unknown on line 0
  ```
  
  Then move the `example` extension from `extension` to `zend_extension` and re-push your app.
  
  If you see the following error:
  
  ```
  NOTICE: PHP message: PHP Warning: example MUST be loaded as a Zend extension in Unknown on line 0
  ```
  
  Then move the `example` extension from `zend_extension` to `extension` and re-push your app.
  
  
  ## <a id="buildpack-extensions"></a> Buildpack Extensions
  
  The buildpack comes with extensions for its default behavior. These are the [HTTPD](https://github.com/cloudfoundry/php-buildpack/tree/master/lib/httpd), [Nginx](https://github.com/cloudfoundry/php-buildpack/tree/master/lib/nginx), [PHP](https://github.com/cloudfoundry/php-buildpack/tree/master/lib/php), and [NewRelic](https://github.com/cloudfoundry/php-buildpack/tree/master/extensions/newrelic) extensions.
  
  The buildpack is designed with an extension mechanism, allowing app developers to add behavior to the buildpack without modifying the buildpack code.
  
  When you push an app, the buildpack runs any extensions found in the `.extensions` directory of your app.
  
  For more information about writing extension, see the [Cloud Foundry PHP Buildpack](https://github.com/cloudfoundry/php-buildpack/blob/master/README.md) repository on GitHub.
  