That's underselling the product, a swarm of nanobots that are (literally, currently) beyond human understanding that are also the only way to construct certain

That's underselling the product, a swarm of nanobots that are (literally, currently) beyond human understanding that are also the only way to construct certain materials and systems. Inheritor of the Gray Goo apocalypse that covered the planet, this kind constructs an enormous mobile mega-fortress with a literal hive-mind, scouring the environment for raw materials and fending off hacking attempts by other nanobots. They even simulate other hive-minds to gain an advantage.