This is technically a crossover between the universe of Fallout and the niche tabletop game Eclipse Phase, which is described as a world of 'transhuman horror.' The main character is a combination of the memories of a random isekai and the memories of a transhuman scientist from Eclipse Phase. I originally published/am publishing this on the site Sufficient Velocities, but decided to cross post here. However, you don't need to know anything about Eclipse Phase to enjoy this novel. I suppose you don't even need to know anything about Fallout, but that would help a lot more.