Despite an interesting concept, potentially interesting characters, and a beautiful cover, this story ultimately fell flat.

The first half of the book was pretty slow, establishing the 4 characters this story is told through. Once I got through that, the story did pick up, with characters starting to interact and connect. Unfortunately, I was left largely unmoved by the outcome of these interactions. If handled differently, certain story beats would have had me on the edge of my seat, but instead the tension just wasn't there and I moved through the story to the end and was left with a sing thought: that was it?

Spoilers ahead...

I think I've narrowed down the elements that have left me feeling rather dissatisfied with the story.
1. Fill. What was the point of having him as a POV character? He served 2 purposes in the story, to give the breaks to Soq and to bring Barron and Martin Podlove together, culminating in Fill's death and setting off the 'war'. His fascination with The City Without a Map, the guilt over his grandfather's past, the things that make him an actual character, aren't explored or brought to any sort of satisfactory ending. He just dies in a ball of fire and the story moves on.
2. The breaks. Talked about endlessly throughout the book. POV characters even express an interest in trying to find out where it came from, how to cure it. But ultimately it gets a shrug. We don't really know what it is, where it came from, but for 'reasons' nanobonding fixes people so they don't die from it so whatever.