On Sun, Feb 3, 2019 at 5:08 PM Dave Horsfall <dave@horsfall.org> wrote:

My vague (and rough) recollection is CP/M -> DOS -> Windows.

"Windows" == Win95 -- which was a user Interface spec the kernel died

IBM CP-DOS -> OS/2 --\

---> NT OS-2 -> NT/WIN ....... Today's Windows

CMU Mach --\ /

---> Mica -/

DEC VMS --/

When Cutler did Mica and then NT OS-2 he did not care what the user interface was. Mica was a pure uk and NT OS-2 was also, but by the time of the product it became a hybrid. Putting a different user interface, be it DOS, OS/2, Unix, VMS or Windows was in the kernel design.

Clem