Upgrading From Symfony 3 to Symfony 4

I started this series off as an extension to the existing GitHut series.

For those that aren't aware, or if you are and would just like a snappy refresher, the GitHut tutorial is the one I consider a very beginner friendly, gentle way to introduce someone new to Symfony, and more generally, modern PHP, in how you can get started.

Lately with the release of Symfony 4, many of the practices that are fundamental to getting started have changed, quite significantly.

Long story short, this breaks many of the Symfony tutorials on this site.

It may be that you have an existing Symfony application that you would like to migrate to Symfony 4.

It may be that you've done the GitHut series and would like to learn how to migrate a Symfony 3 codebase to a Symfony 4 project structure.

Whatever your requirements it has turned into a more protracted migration / upgrade path than one or two videos could cover, so I've created this as a separate follow-on series.