@1iceloops123 I think they use some things from WINE, but they always have to rewrite parts of that anyway, because they don't have a Unix-like under-layer for WINE to plug into.

They're sort of screwed: If they ever reimplement enough of Windows to be a usable competitor, Microsoft will sue them out of existence. But also, since they target all Windows versions since NT4 (or at least the used to), they'll always be chasing after a competitor with more resources and falling farther behind.