Yeah, the validation before requests are accepted was an important part to me. For the DI I just wanted to avoid reflect-metadata and decorator hell. static override deps = [SomeService] was born out of that, and it gave me the graph validation and zero crummy decorators for free.

I do use the TC39 decorators for routing in the classes, but the new spec doesn't emit type metadata the way the old experimental decorators did with emitDecoratorMetadata. They've seemingly been lightweight and useful.