@juandesant @dataandpolitics @glennf

I think it would be more accurate to claim #MacOSX was an updated port of #osfmk (OSF, CMU, Apple) with a brand new driver SDK (post-merger Apple) using a new port of 4.4BSD-Lite2 (UC Berkeley) hosting a new WindowServer (post-merger Apple) running frameworks ported from OpenStep (NeXT: Cocoa) and classic MacOS (Apple: Carbon) that were both refactored to share common infra (post-merger Apple: CoreFoundation).

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@juandesant @dataandpolitics @glennf

1. The kernel (#xnu) was amalgamation of code that was mostly independent of NeXT. #NeXTSTEP was based on Mach 2.5 & 4.3BSD with an ObjC based DriverKit. xnu was built from #osfmk which was Mach 3.0 and ported to Mac HW as part of the #MkLinux project, a fresh rebase of 4.4BSD-Lites2, and the driver system (#IOKit) was a ground up redesign, despite the existence of DriverKit and NuIO.

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