Tatar_Khan There are suggestions to a more advanced civilization and science that existed before, and that some artifacts are from that period.
The Endless games also did that. Endless Space had all the fancy tech, then a prison ship crash landed on a planet, mixed with the locals, and centuries later you got Endless Legend. Magic is in fact poorly understood technology, and has influenced the evolution of the planet.
Gentlemen Bastards also has that. Some race that disappeared and left behind odd structures. Though it’s just materials people don’t understand, not technology per say. Though it is believed the race died due to abusing magic.
Great books btw, mostly. Lies of Locke Lamora and Republic of Thieves were great. But Red Seas Under Red Sky was…the author admitted to being sick for a good amount of writing the book. And I believe him. Could have worked as two short stories, but the attempt to inorganically slap them together created MANY problems throughout.