The Unmaking Of Heaven — Sam Smith

In this the fifth and final book of the series all the characters are post-organic beings, minds become machines, calling themselves Synths or Eternals. Some Synths - led by the Shining Knight - decide that all Synths, including Sexthetes and Puzzlers, are Abominations, themselves included, and they set out to destroy them all. The survivors are those who hid. As initially did the Shining Knight.