I was actually a tiny bit disappointed - I was hoping for a closer coupling of tetris-logic to life-logic :-) Per https://conwaylife.com/wiki/Universal_computer the first turing-machine-in-Life goes back to 2000, and "building a CPU to run code" is at this point the "obvious" way to do it. See https://nicholas.carlini.com/writing/2020/intro-to-circuits-... for a tutorial with a (circular) "final goal of designing an Intel 4004 and using it to simulate the game of life."