Chaos Terminal by Mur Lafferty

Mallory Viridian would rather not be an amateur detective, and fled to outer space to avoid it.but when one of the new human arrivals on a space shuttle is murdered, she's back in the game.
Mallory Viridian would rather not be an amateur detective, thank you very much. But no matter what she does, people persist in dying around her-and only she seems to be able to solve the crime. After fleeing to an alien space station in hopes that the lack of humans would stop the murders, a serial killer had the nerve to follow her to Station Eternity. (Mallory deduced who the true culprit was that time, too.)
Now the law enforcement agent who hounded Mallory on Earth has come to Station Eternity, along with her teenage crush and his sister, Mallory's best friend from high school. Mallory doesn't believe in coincidences, and so she's not at all surprised when someone in the latest shuttle from Earth is murdered. It's the story of her life, after all.
Only this time she has more than a killer to deal with. Between her fugitive friends, a new threat arising from the Sundry hivemind, and the alarmingly peculiar behavior of the sentient space station they all call home, even Mallory's deductive abilities are strained. If she can't find out what's going on (and fast), a disaster of intergalactic proportions may occur..