Second paragraph of third chapter of After Atlas, by Emma Newman:

I’ll watch your back if you’ll watch mine.

This is the second in the four-volume Planetfall series by Emma Newman, which I have read completely out of order. (Third, fourth, first.) I’m afraid this lost me pretty early on when the protagonist, a police detective, was compelled by his bosses to investigate the murder of a former close friend. Sure, he is indentured through an ‘orrible system of cyber-slavery, but really, assigning someone like that is a crazy thing for a police force of any size to do. I read patiently through for the payoff, but it didn’t come. You can get it here.

This was my top unread book acquired in 2020. Next on that list is Killdozer!, by Theodore Sturgeon.