That project sent me down a rabbit hole learning about CRDTs. I'd love to learn more about the history of the Notes implementation. Who did it? What background

That project sent me down a rabbit hole learning about CRDTs. I'd love to learn more about the history of the Notes implementation. Who did it? What background did they have? Their "topotext" construct is similar to RGA, but different from any paper that I can find. I think it was invented by the developers. The drawing thing I did because it was interesting - the kind of data that would be fun to have to play around with character / shape recognition. I export it as SVG for my "notes2html". But since my output doesn't take into account the pen angle, pressure, and velocity, it isn't going to be as good as Apple's PNG. The actual raw data for the stroke is a series of PKCompressedStrokePoint structures that contain timestamp, position, radius, aspectRatio, edgeWidth, force, azimuth (scaled radians), altitude, and opacity. I had to look at disassembled libraries to figure that part out. Peeking at PencilKit again with Hopper makes me think that the structure layout may have changed since I wrote that code.