September 28, 2017 Javier Eguiluz

One of the biggest changes of the upcoming Symfony 4 version is the removal of bundles to manage the application code. Bundles will still exist as third-party plugins installed in vendor/ , but your own code will live by default in the src/ directory and it will use plain PHP namespaces instead of bundles.

In Symfony 3.4 we worked towards simplifying bundles even more. That's why we deprecated bundle inheritance and we'll remove it in Symfony 4.0. This inheritance mechanism was traditionally used to override some templates, controllers and other elements of third-party bundles. In Symfony 4.0 you'll need to use alternative solutions to override those elements: