4.0

I remember reading this book twice and liking it a lot, but I couldn't remember who wrote it or if it was the same one until I scoured the internet to find the cover of the one I read (this one: https://pictures.abebooks.com/isbn/9780439540346-us.jpg)
I'm glad I read it when I did, because I would not have been at all interested if the copy I picked up had this romance-novel-looking cover.