You'd be surprised how many people miss that runtime drives this. I've seen many discussions where people claimed "you can implement all this is a library" :)
> it would be absurd to build a compiler and runtime system for, eg., Elixir that is not able to execute GenServers.
Well, Akka did it on top of JVM: https://doc.akka.io/docs/akka/current/typed/fault-tolerance.... Can't say about its limitations though.
I undrstand, everything concurrency is definitely not easy to implement in "User land" and is something you want good primitives for – why I am also amaxed over this project as they must have embedded that functionality (the scheduler) in the executable (Which they also say they did).
> Well, Akka did it on top of JVM ...
> Akka is a toolkit for building highly concurrent, distributed, and resilient message-driven applications for Java and Scala.
Akka does not seem to claim that they build a new runtime for BEAM languages?