I have found out that as soon as you describe your backend as Spring(Boot) application you have already failed at integrating and using Spring(Boot). Ideally, S

I have found out that as soon as you describe your backend as Spring(Boot) application you have already failed at integrating and using Spring(Boot). Ideally, Spring should be extremely thin layer on top of your java application with, ideally, one-line controllers delegating tasks to your services and custom bean factories where you manually wire your services. Also, your java application should not have any Spring related annotations and dependencies. This really shines in hexagonal architectures where Spring is outside and is just used as input/interface to an application.