It is possible to build one by humans or Bobs, it just requires lots of resources and the determination to see it through. As indicated by several people, the tech itself isn't terribly complicated. They have also figured out how to build AIs, whereas humans could only build either AMIs or replicants. For example, their fusion torches have a much higher acceleration than SURGE drives but can't sustain it indefinitely. For example, they have no subspace tech but, as a result, have considerably improved their fusion reactors and engines.

Alternate Techline: The Quinlans, the people of the topopolis, advanced in some areas far beyond humanity but either didn't discover or did not get far in some other areas.

They've even started building a 'matrioshka brain' in an uninhabited system. Unlike Starfleet, the Skippies aren't pushy about their beliefs. To a lesser extend, the Skippies also want Bobs to stop interacting with 'ephemerals', but their view is that it keeps the Bobs from attaining their true potential. The others just dismiss them as harmless wackos.

Alien Non-Interference Clause: The Starfleet faction insists that all Bobs adopt this policy or else.

Determined to find Bender, Bob, several other Bobs, and Bridget infiltrate the topopolis using androids shaped as the aliens. Meanwhile, while investigating the disappearance of Bender, Bob locates a new space-faring species, which made its own homeworld uninhabitable and moved the survivors into a vast space habitat humans call a topopolis (basically, a giant tube stretching for a billion miles and weaving around the star several times). A faction called Starfleet insists on it, citing their own version of the Alien Non-Interference Clause. Some of the factions insist on cutting off all contact with biological life forms, including humans.

Factions are starting to form among the Bobs, and 'replicative drift' means that many of the later-generation Bobs are starting to become completely different individuals from the original Bob. Taylor, published in 2020, is the fourth book in the Bobiverse series (preceded by We Are Legion (We Are Bob), For We Are Many, and All These Worlds).

The bobiverse series