Book of Iron — Elizabeth Bear

Bijou the Artificer is a Wizard of Messaline, the City of Jackals. She and her partner--and rival--Kaulas the Necromancer, along with the martial Prince Salih, comprise the Bey's elite band of trouble-solving adventurers.

But Messaline is built on the ruins of a still more ancient City of Jackals. So when two foreign Wizards and a bard from the mysterious western isles cross the desert in pursuit of a sorcerer intent on plundering the deadly artifacts of lost Erem, Bijou and her companions must join their hunt.

The quest will take them through strange passages, beneath the killing light of alien suns, with the price of failure the destruction of every land.