The setting is thick and juicy: a barely-terraformed world, several centuries into a war that the planet and population can barely support. Technology is biological, creepy-crawly, and taken for granted; the war is permanent, clearly the center of everything that's gone weird about their (splinter-Islamic) culture, and taken for granted. Some people can shapeshift into dogs or birds. Aliens (i.e. humans from other worlds) hover around the edges. All of these things have layers, fractures, subculture clashes, and history. We get all of it from the inside, tangentially, because who bothers thinking about the centuries-old causes of day-to-day shit? It's very well done.
Nyx is that rare thing, a protagonist who genuinely doesn't know she is one. Her life is, in fact, day-to-day shit. She isn't nice. She makes petty mistakes, knowing they are mistakes as she does so. She doesn't dream of a better life because she's working too hard at this one, and when things get worse, well, that's the new normal. She doesn't blame other people because she knows it was her screwup. It is despair indistinguishable from never giving up, fatalism that you could call responsibility -- though never heroism -- perhaps only because we see it from inside Nyx's head. I think this is the strain of "sociopathically brutal hero" SF/F that I want.
The plotting, on the other hand, is a mess -- weirdly paced, turgid with characters and plot threads, and with a shoehorned-in denoument. All the stuff I've just been praising nearly passed me by because I was waiting half the book for the story to happen. It never really did; just various phases of shit in Nyx's life.