Parallelism isn't easy, so the core team is expending time to get it done correctly and released before 1.0. Crystal doesn't have anything like the GIL, and the

Parallelism isn't easy, so the core team is expending time to get it done correctly and released before 1.0. Crystal doesn't have anything like the GIL, and the compiler already enforces some simple rules, like type flow not being available on instance variables because they could be changed on another thread. You can't expect the world from any new project straight away.