That was weird: an hour ago I was reading "Version Control with Git" about merging and thinking "Hey, this is all just category theory", I then have a look at HN, and see this.
"foo" occurs in the lyrics to Cab Calloway's 1939 Jumpin' Jive, as in this clip, also featuring fabulous tap dancing from the Nicholas Brothers: https://www.youtube.com/watch?v=_8yGGtVKrD8
I should add that I have no affiliation with mathsgear, in fact, I was unaware of their existence until just now. They seem to have lots of nice stuff: https://mathsgear.co.uk/collections/shapes
And in 3 dimensions it's points and planes that are dual - and finding the line between two points or the common line of two planes can now be done in a similar way, but using Plücker coordinates for the lines instead.
I'd have thought AVR assembler was a better choice these days - a nice orthogonal 8-bit RISC architecture, and you can use gcc, gas etc. (as well as being able to run your code on an Arduino).