[koalahedron]

Thanks again. Like you said it is fun to dream (ask the "Scheme Machine" guys sometime about how they would go about it now), but practically with technology like Julia's Zygote:

https://github.com/FluxML/Zygote.jl

the efficiency of autodiff might be similar to that of an opcode anyway.

So, how did DEC do on the Alpha processor? I always heard good things about it--IIRC (I didn't) it was ~~based~~ to replace the VAX, but 64 bit. I learned PDP-11 assembler at RPI, during their college program for high school students in about 1984. We hand assembled code and really got to know the architecture.

[koalahedron]

By the way, back to the original topic, a bare-bones machine like the KIM-1 also required a lot of hand assembly.

I guess everybody is gone from this post too, but I wonder if there is a fixed point corollary to Godwin's law--if you post enough off topic comments, you reach the original topic again. :)