Silicon Zeroes [1] starts out slightly more abstracted than what you described (byte-level operators, register files, ALUs, that sort of thing) and builds up to

Silicon Zeroes [1] starts out slightly more abstracted than what you described (byte-level operators, register files, ALUs, that sort of thing) and builds up to a full CPU. [1] https://pleasingfungus.itch.io/silicon-zeroes https://pleasingfungus.itch.io/silicon-zeroes