1. I believe that Dependency Injection is a fundamental block of FastAPI framework philosophy. I wouldn't say that Dependency Injection Transforms FastAPI Applications, because Dependency Injection is a fundamental block of a FastAPI applicaction. I think we can transform FastAPI PROJECT with some tools, which are beyond FastAPI core.

2. I feel that if you'd like to share how dependency injection works especially in FastAPI - you should cover nested dependencies (like we are doing with OAuth, whatever, ...)

3. What about taking a word about existing FastAPI code about some useful existing classes. Might a part of your Clean Code Principles section

Thank you.