I was starting to use Kitura but it seems the community is more in favor of Vapor right now. I moved on to Vapor as a result. IBM seems like it might abandon the project like they did their Swift Packages website.
The API's not stable, the framework is in very active development.
I imagine things will settle down in a year or two - until then, there are so many great alternatives (other languages), that I don't see Swift gaining much ground.