I bought this thinking it was going to be a piece of steampunky Science Fiction.
I was wrong. While it has many of the elements of Steampunk, it *almost* reads more like a fairy tale than Sci-Fi. In fact, it felt a bit like an extended parable. The quote on the cover of the book says, 'A gorgeous meditation on what it means to not be human,' but until you've read a few chapters you won't realise that the comment is true on more than one level.
As I read the story of the clockwork protagonist, I was continually reminded of of the many groups in our world who have, at various times and for various reasons, been regarded as less than fully human. I also found my thoughts occasionally drifting in theological directions, as I considered clockwork Mattie's relationship with her maker.
It's a strangely moving, well-told story. If I've only given it four stars, it's because I personally found the ending unsatisfying. But that may be just a very personal quirk - I seem to be finding the ending of MOST books unsatisfying these days.
Buy it. Read it. Whether you like the ending or not, it's certainly NOT one of those books that will leave you wondering why you wasted hours of your life reading it. It's a story that will stick in your mind, providing food for thought long after you've finished it.