Upgrading your Symfony application is the most crucial mission you can’t avoid. The difficulty of this job may differ from project to another depending on the way it’s created and also the project size.
For the actual case, it’s about upgrading a Symfony API, which means that some parts of migration are not mentioned in this guide like the Forms, but don’t worry, I will leave you the link of a git repo that covers this part.
It’s clearly evident that following the technical guide will not resolve all your bugs when upgrading. But in general, it covers the most basic principal actions you have to do.
In case your code crash in some parts, you need first to verify if it’s about your business logic which cause the bug. If true, you need to change the manner in which your code is implemented. If not, you have to DIG and DIG.
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