[TUHS] Bootstrapping UNIX - how was it done

[Dan Cross via TUHS]

On Mon, Mar 23, 2026 at 1:54 PM segaloco via TUHS <tuhs at tuhs.org> wrote:
> On Monday, March 23rd, 2026 at 02:05, Adam Koszek via TUHS <tuhs at tuhs.org> wrote:
> > What editors were used for early B, B+, C and early kernel?
>
> My understanding is that prior to UNIX being self hosting, Ken was
> editing things in QED under GECOS on the 645 BTL had gotten for Multics
> development, carrying over the PPT output to then load up on the PDP-7.

I believe it was a GE-635 that was used for bootstrapping Unix onto the PDP-7:
https://www.read.seas.harvard.edu/~kohler/class/aosref/ritchie84evolution.pdf

Despite the similarity in name, the 635 and 645 were very different machines.

        - Dan C.