Zero Days. Ruth Ware

Jacinta "Jack" Cross and her husband Gabe are the best security hackers. Companies hire them to test the strengths and weaknesses of their systems: Jacinta performs the physical hacks, while Gabe takes care of the digital aspects. After failing a routine task, Jacinta returns home to find her husband dead. And the police seem to consider her the only suspect.

Suddenly determined to escape, Jacinta realizes that she has little time to find the killer and find out who she can trust among her family members, old friends, and even enemies. The closer she gets to the truth, the clearer she sees that there is much more at stake in this cruel game than she first thought...