I've mixed feelings about it. As advertised it can be somewhat useful for business rules-rich apps, yes, but most of the times the application side of the proje

I've mixed feelings about it. As advertised it can be somewhat useful for business rules-rich apps, yes, but most of the times the application side of the project will just grow exponentially faster than your core - especially if you don't keep an eye on commits, as some of your coworkers may choose the easy way out and push business logic on the application side instead of refactoring... It's a clean architecture from a business logic standpoint, indeed, but it doesn't do a lot to keep the outside of the hexagone well organized (beside the port/adapter pattern), and that side of the app can grow into a mess really fast if your team lack experience. Not as many abstraction layers than in a classic J2EE app, though. It's not that bad.