Modern novels in which the protagonist inherits alien technology or warships.

Future weapons experts. Very good, but the update is slow, and the early stage is relatively slow. After the submarine empire was built behind, all kinds of mechs were available, and then there was a great commotion in Atlantis. Finally, the alien detector was discovered, and aliens invaded ... In short, the early development was a bit slow, so we should persevere to see it.