As the labs folks all probably know, Vic became the Executive Director of division 91(two levels beyond department head).
This was after Research and Multics and, I think, Safeguard.
One of the early things he asked after quizzing various folks about what was going on in the division was "Where is your source code control system?".
The question fell to Rudd Canaday (then a department head under Vic).
And SCCS was thus born.

And who doesn't remember SP&E Aleph Null articles?


On Sat, Apr 9, 2022 at 7:47 AM Douglas McIlroy <> wrote:
> Single Level Storage is an awesome concept and removes so many ugly
> hacks from algorithms that otherwise have to process data in files.

This was Vic Vyssotsky's signature contribution to Multics, though in typical
Vyssotsky fashion he never sought personal credit for it. Other awesome
Vyssotsky inventions:

BLODI (block diagram), the first data-flow language, for sample-data systems.

Parallel flow analysis (later reinvented and published  by John Cocke). Vic
installed this in Fortran to produce diagnostics such as, "If the
third branch of IF
statement 15 is ever taken, then variable E will be used before being set".

Darwin, the original game of predation and self-reproduction among programs. keeps a descendant version going 60 years later.

A minimum-spanning-tree algorithm quite different from the well-known methods
due to his colleagues Bob Prim and Joe Kruskal, again unpublished.

Not long ago on TUHS, Andrew Hume told how Vic found the same isolated bug in
dc by mathematically generating hard cases that Andrew stumbled on by accident,

As you may infer, Vic is one of my personal computing heroes.