Is There a Tooling API to Identify Apex Classes?

It'll make it possible for tooling around dependency injection because you can say, cut your customer credit class, implement this interface and then you give them a UI that says, you know, whenever X, X, X runs, use this implementation of that interface. And get them away to do that. You can already go through every you can enumerate every apex class and then see what they implement and build that list yourself. I'm just talking about doing this real time within the apex language. Oh, absolutely. Or also a managed package where you might have an interface in your package as a global and the customer, the installing or could then provide their implementation of it at runtime.