It says "Windows isn't supported". It's there a reason and is that forever?
Also, off you're going to compare the concurrency to Erlang and Pony, an example with multiple processes doing message passing would be more telling.
Looks like the runtime depends on rustix, and in turn, libc. Presumably building in cygwin/msys isn't out of the question. Other dependencies peppered around but this one seems like the least mutable.