The Bullet Catcher’s Daughter by Rod Duncan. Published by Angry Robot

Elizabeth Barnabus is a pretty good private detective, but that’s an unseemly job for a young woman, so she performs her job as her own brother. Currently, she’s trying to find a missing millionaire and a number of mysterious machines. In her gaslit world she must cross swords with dastardly scoundrels, nasty scoundrels and spooky alchemists from a traveling carnival. But her worst fear is running into an agent from the dreaded Patent Office and when that happens, nothing will ever be the same.
Steampunk at its best. Engaging characters, spectacular settings and snappy dialogue