Does Unity support application bootstrapping?

I’m primarily looking for a unified solution to manage certain application level logic, e.g. dependency injection. I was hoping that there was some way that I could identify a class, or script, as code to be executed on application start up where the objects initialized would live for the life of the application (i.e. the game).

Barring that I figure I can attach initialization code to a game object on a per scene basis. I don’t really like that as a solution, as I hate the idea of dependencies that need to be managed, essentially manually, for every scene. (That and I’d also like to avoid the unnecessary task of reinitializing objects on a scene-by-scene basis when the user moves from one scene to the next).

You can also run code ONCE when the SCENE loads. Amazing;