This is a broader theme in how technology develops. When I look at technologies like bitcoin, it's just proof of work/puzzles (a well-understood defense to syb

This is a broader theme in how technology develops. When I look at technologies like bitcoin, it's just proof of work/puzzles (a well-understood defense to sybil attacks) + basic crypto primitives like signatures + some of the p2p stuff from bittorrent, etc. There's real genius in combining the pieces, though. I also spent a few years in serious CS academia so not clear how widely these things (especially puzzles) were known beyond universities.