An established practice in web applications is to resize user images during uploads: I am suggesting a different approach instead, which relies in creating on-the-fly the requested size thumb.
I recently wrote about the assets:install command, but there’s a more interesting way to handle your assets: Assetic.
In your Symfony application there are bound to exist many assets (JS, CSS, and so on) either created by you or provided by third-party bundles.
As part of your deploy procedure, you usually have to use some Symfony console command to actually make the assets available to the frontend of your application.
Let’s start with the most basic solution: the assets:install command.