I agree -- I was just around in the last days of Windows 3.1 and co-operative multitasking (which is close to async with a different coat), and it was a horribl

I agree -- I was just around in the last days of Windows 3.1 and co-operative multitasking (which is close to async with a different coat), and it was a horrible experience, and fighting hangs was a never-ending task. I would go further, and say assuming your program is doing "interesting work" (not just calling a database / reading a file and returning the results), use a threadpool. In almost all applications threads are fine, certainly when you are comparing threaded Rust to people using Python/Ruby.