[TUHS] Is there a good, even definitive, list of reimplementations of the Unix kernel? What would good cut-off criteria be?

[David Arnold via TUHS]

On Tue, Apr 21, 2026, at 11:59 AM, jslee via TUHS wrote:
> On Mon, 20 Apr 2026, at 08:24, steve jenkin via TUHS wrote:
>> Very remiss of me, I failed to Consult the Oracle first: Peter Salus' 
>> "Quarter Century of Unix", 1994 [ pre Linux ]
>
> Per Ted Tso’s reply earlier, Linux was already well and truly alive before 1994
>
> Also, OMU by Dr Steve Hosgood in the 1980s, archived by Alan Cox of Linux fame:
>
> https://codeberg.org/EtchedPixels/OMU

Helios was a largely POSIX-compatible "microkernel" for the Inmos Transputer T4xx / T8xx series, written by Perihelion in the UK.

I quote microkernel, because it was at heart a distributed system, and for example, your filesystem, your console, and your application process might end up running on entirely different CPUs, potentially in separate boxes, depending on configuration.  It has some conceptual commonality with Plan9, although members of both groups have disclaimed knowledge of the other's work at the time.




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