By Marie Rutkoski.
A fun adventure story, tight prose, strong characters, creative worldbuilding. Basically, I think the writing is pretty strong, and refers to some important truths about relationships (mothers and friends) without getting bogged down in angst. Petra is an impulsive, get-up-and-go kind of person, but it seems her heart is in the right place. The characters are unique, possibly larger-than-life, and even the (obvious) villain seems more heartless than evil. (I also want to say that Dr. John Dee is creepier in this book than in any other book I've read where he appears, and certainly doesn't match the gentle incarnation in Midnight Never Come.)
My chief concern about this book is that I'm not finding that much to think about after finishing it. This might be because of quibble #1: the book ends in a place that looks sort of like a happy ending, but is really just a stopping point if you think about it. It's clear that there will be Consequences in future books, and the author mentions at least 3 more planned on her site.
My second quibble is that this book is set in medieval Bohemia, and there's no mention of the church, God, or religion that I can recall. (Upon skimming through again, I found one reference to an angel figure in the clock, and there might be more.) There's even a story about the woman who halted the burning of magicians 800 years previous, but no explanation of why they were burning them in the first place. I don't know much about Bohemian history, but it struck me as an odd omission especially when discoveries such as heliocentrism are included in the story.
Overall, a fun story that isn't completely unrealistic; I'd recommend it.