Ubuntu on Windows

"Linux geeks can think of it sort of the inverse of "wine" -- Ubuntu binaries running natively in Windows. Microsoft calls it their "Windows Subsystem for Linux"."

I find it amazing that you can have such a functional Ubuntu environment by translating system calls. Microsoft does have the advantage of Linux being open-source I suppose, while the Wine project had to reverse engineer DLLs. Or have you supply them on your own.

Windows NT was designed from the start to have modular subsystems. It was most infamously used to provide a POSIX subsystem which really only checked boxes on government acquisition forms. :-)

The reason WINE went with the library emulation route is because: (a) the Windows kernel doesn't have a stable system call layer, and (b) the Win32 API is massive anyway.

Windows has an easier time emulating Linux at the very lowest levels because Linux has an ABI stable system call layer. If you emulate those, you can run ANY Linux binary.

It also means Microsoft doesn't have to ship or support hundreds of Open Source projects. They ship the syscall layer, and distributions ship the user layer.