The Tinkerer's Daughter

Breeze is an outcast, a half-breed orphan born into a world torn apart by a thousand years of war. Breeze never knew her elven mother, and when her human father is recalled to the war, he leaves her in the safest place he knows: in the care of a reclusive tinker. The Tinkerman's inventions are frightening at first—noisy, smelly, dangerous machines with no practical use—but when the war comes home, Breeze sees an opportunity. If she can pull it off, she'll change the world forever. If she fails, she'll be considered a traitor by both lands and will be hunted to her death.