Libuv supports windows and in some ways only exists because windows support is needed; on Unix/Linux where Node started, libev was sufficient; libuv was created to facilitate the windows port of node - though it is now standing in its own right.
Later I discovered that it is possible to do efficient epoll emulation on windows so then I wrote wepoll. With it you can just stick to the good ol' epoll/kqueue model and still support windows.