If you have ever wondered why Doctrine entities cannot be final, this is the article that answers it. And the answer stops being true in PHP 8.4.
This is the largest change in the Symfony 8 and Doctrine 4 move, and it is not really a framework change at all. It is a PHP language feature removing the need for a fifteen-year-old workaround.
You run Rector. It rewrites every docblock into an attribute. The diff looks perfect. You commit, deploy, and your entities are no longer recognised at all.
Symfony 6.4 stops receiving bug fixes in November 2026. Security fixes continue for another year, until November 2027, but after that the version is done.
If you are on 6.4, this is your window. And the good news is that the upgrade is much less work than the version numbers suggest, provided you understand what Symfony is actually asking you to do.
Autowiring is one of the better things to happen to PHP. Typehint a class in a constructor, and Symfony finds it, builds it, and hands it over. No configuration, no factory, no container gymnastics. A generation of PHP developers now writes dependency injection without ever thinking about it, which is exactly what good tooling should achieve.
Set opcache.save_comments=0 on a Drupal site running annotation-based plugins, rebuild caches, and you get this:
Four packages, one playbook. This should be a boring afternoon, and it mostly is — except for one ordering problem that breaks almost every tutorial on the subject, in a way that only shows up on a genuinely fresh server.
So let me start there, because if you understand it the rest is just YAML.
Here is the Dockerfile almost everyone writes first:
Docker has fundamentally changed how PHP applications are deployed. Modern Symfony, Laravel, and custom PHP systems increasingly rely on containers for local development, CI/CD pipelines, horizontal scaling, and production infrastructure consistency.
But Docker has also created a dangerous misconception inside the PHP ecosystem:
PHP-FPM has become the standard execution model for modern PHP infrastructure. Whether applications run on bare metal servers, inside Docker containers, or in Kubernetes clusters, PHP-FPM usually sits directly behind Nginx and processes every dynamic request entering the application stack.
Modern PHP infrastructure has evolved far beyond the traditional model of deploying a small application onto a single Linux server and exposing it directly to the internet.