> I think that stackless coroutines are probably a necessary evil in system languages as full stack switching might have too much overhead. I think it's worth

> I think that stackless coroutines are probably a necessary evil in system languages as full stack switching might have too much overhead. I think it's worth noting that the big operating system kernels - perhaps the ultimate target of "system languages" - tend to use stackful coroutines rather than stackless. Stack switching tends to be similar speed overhead than stackless, despite surface appearances in how the code may appear. Stackless tends to do more memory allocation and freeing, though.