UPGRADE FROM 2.2 to 2.3 ======================= When upgrading Symfony from 2.2 to 2.3, you need to do the following changes to the code that came from the Standard Edition: * The debugging tools are not enabled by default anymore and should be added to the [`web/app_dev.php`](https://github.com/symfony/symfony-standard/blob/2.3/web/app_dev.php) front controller manually, just after including the bootstrap cache: use Symfony\Component\Debug\Debug; Debug::enable(); You also need to enable debugging in the [`app/console`](https://github.com/symfony/symfony-standard/blob/2.3/app/console) script, after the `$debug` variable is defined: use Symfony\Component\Debug\Debug; if ($debug) { Debug::enable(); } * The `parameters.yml` file can now be managed by the `incenteev/composer-parameter-handler` bundle that comes with the 2.3 Standard Edition: * add `"incenteev/composer-parameter-handler": "~2.0"` to your `composer.json` file; * add `/app/config/parameters.yml` to your `.gitignore` file; * create a [`app/config/parameters.yml.dist`](https://github.com/symfony/symfony-standard/blob/2.3/app/config/parameters.yml.dist) file with sensible values for all your parameters. * It is highly recommended that you switch the minimum stability to `stable` in your `composer.json` file. * If you are using Apache, have a look at the new [`.htaccess`](https://github.com/symfony/symfony-standard/blob/2.3/web/.htaccess) configuration and change yours accordingly. * In the [`app/autoload.php`](https://github.com/symfony/symfony-standard/blob/2.3/app/autoload.php) file, the section about `intl` should be removed as it is not needed anymore. You can also have a look at the [diff](https://github.com/symfony/symfony-standard/compare/v2.2.0%E2%80%A62.3) between the 2.2 version of the Standard Edition and the 2.3 version.