Still the Sun by @CNHolmberg

Pell is an engineer and digger by trade-unearthing and repairing the fascinating artifacts left behind by the mysterious Ancients who once inhabited the sunbaked planet of Tampere. She'll do anything to help the people of her village survive and to better understand the secrets of what came before.

Heartwood and Moseus are keepers of a forbidding tower near the village of Emgarden. Inside are the remnants of complex machines the likes of which Pell has never seen. Considering her affinity for Ancient tech, the keepers know Pell is their only hope of putting the pieces of these metal puzzles together ...