War Girls by Tochi Onyebuchi
In 2172, when much of the world is unlivable, sisters Onyii and Ify dream of escaping war-torn Nigeria and finding a better future together but are, instead, torn apart.
Review from Booklist Reviews:
In a futuristic Nigeria torn asunder by civil war, catastrophic battles are fought using soldiers augmented with bionic limbs and artificial organs. Sisters Onyii and Ify find themselves on opposite sides of the war. Eldest sister Onyii is the practical one. She's a caregiver and leader who will stop at nothing to see Ify have a better life. However, Ify doesn't necessarily like being coddled. When a years-long civil war rips the sisters apart, they will do anything to fight their way back to each other. Onyebuchi (Beasts Made of Night, 2017) uses a sf setting to explore very heavy, real-world issues, like climate change, nuclear disasters, and child soldiers. Onyii and Ify both face horrors as children of war and live with the traumas induced by being exposed to such violence at a tender age. The story also explores bioaugmentation and what it means to be human while asking whether we should use a technology just because we have it. Onyebuchi makes up for the sluggish narrative start with his staggering, imaginative world, which immediately draws readers in and effortlessly makes them feel and root for its characters. This brilliant novel about sisters, war, and freedom should be in every sf collection.