Ascension by Jacqueline Koyanagi

Alana Quick is the best damned sky surgeon in Heliodor City, but repairing starship engines barely pays the bills. When the desperate crew of a cargo vessel stops by her shipyard looking for her spiritually-advanced sister Nova, Alana stows away. Maybe her boldness will land her a long-term gig on the crew. But the Tangled Axon proves to be more than star-watching and plasma coils. The chief engineer thinks he's a wolf. The pilot fades in and out of existence. The captain is all blond hair, boots, and ego... and Alana can't keep her eyes off her. But there's little time for romance: Nova's in danger and someone will do anything -- even destroying planets -- to get their hands on her!