A very important point. Machines which can self-replicate from naturally occurring raw materials pose some daunting engineering challenges. However, consider h

A very important point. Machines which can self-replicate from naturally occurring raw materials pose some daunting engineering challenges. However, consider how much of our current approach to designing spacefaring robots and their subsystems is influenced by the materials and economic climate we have available here on earth. We deal with severe tradeoffs guided by making robots as lightweight as possible, as reliable as possible (because one failed servo is extremely expensive to replace once you're on mars) and use highly modular components which are well-suited to an expansive global supply chain. What do you design differently when heavy metals are relatively plentiful, weight is mostly irrelevant, scrapping a failed robot is more acceptable and organic substances are scarce? If the parts of the robot are made almost entirely using additive manufacturing processes and circuitry is integrated into the structure you can reduce or remove the need for fasteners and possibly do without conventional insulated sheathing, etc. The path to self-replication is to reconsider and reinvent a technology stack which minimizes the set of dependencies, and that is a very interesting challenge.