Ruby 3, Concurrency and the Ecosystem
I've a hard time seeing how this could work out. Admittedly it's been some time since I did ruby but as I recall there was a shocking amount of mutability going on in the core language and throughout the ecosystem. Mutable lists, tables and strings everywhere, even the "constants" of ruby were mutable by default which bit me more than once.I'm just not convinced that good parallellism is something you can successfully bolt on to a language 25 years down the road. The languages I've seen do a really good job all embraced parallelism as an important problem from the start and had a strong policy of immutability by default and good persistent data structures. Such a clear  commitment permeates the ecosystem and you get libraries with clear parallelism stories .Hopefully I'm wrong and this will all work out great for ruby.