My Rare Class is Artificer!

"Engineering is the closest thing to Magic that will ever exist." - Yoshi Yoshimura, a genius Engineer recreates the schematics for a next-generation weapon but is betrayed by a spy, killed and then reincarnated in a fantasy world in the body of a lesser noble's son. Can he use his rare class to save his people from economic ruin? [Isekai, Fantasy, System.]