Comment by solidsnack9000

> Because concurrency is supported through an Apple API rather than being explicit in the language’s design, using it is currently very much coupled to iOS or macOS development.

I am not sure this is accurate, because libdispatch has been ported to Linux:

https://github.com/apple/swift-corelibs-libdispatch

They are "...early in the development of this project..." but server-side frameworks use it.