> And what might the precursor techs for such a replicating machine look like?

I would wager, attempted mischief, that words themselves are the self-replicating machine, to the Universe..

Think about it. These very characters, here on this page .. motivate the pro-creation of yet more, and so much the human organism is designed exclusively for the propagation and 'existence' of these words, that eventually, to the Universe, it must look like each letter is but a sperm, off to meet some fertile substance designed to fuse another font of near endless replication, reproduction, duplication, consumption ..