Why I’m Learning Perl 6
> Concurrency is hard and if you want M:N thread multiplexing (i.e. WEB SCALE CODE, where application threads aren’t pinned to pthreads) your options today are precisely Erlang, Go, .NET, and Perl 6.Putting aside the "web scale" jokes (http://www.mongodb-is-web-scale.com/), this statement is still absurd.Every major language, or at least the ones that matter for backend development, has support for thread multiplexing / coroutines / fibers, whatever.  Perhaps not in the core language syntax or standard library.  But it's easy to implement with native code, and so SOMEONE has implemented it in a library if the language has an FFI.Java, and all of the other JVM-based languages in turn, have Quasar (http://docs.paralleluniverse.co/quasar/).Ruby has support for primitive fibers baked into the standard language (https://ruby-doc.org/core-2.1.1/Fiber.html), and likewise community gems with more robust functionality like Quasar.Python 3 likewise has this out of the box (https://www.python.org/dev/peps/pep-0492/).The list goes on and on:  https://en.wikipedia.org/wiki/Coroutine#Programming_language....