The Decemites. The Echelon, #1

"Combination of The Hunger Games, The 100 and Divergent!" They said nothing could survive outside. They lied.Welcome to Echelon, a domed city that protects the survivors of a ravaged Earth. Here, the wealthy elite live in Sky, high above the poor dwellers of Dirt. And Dirt children known as Decimites are injected with nanobots, allowing them to survive in a world ravaged by toxins. Forced to gather resources from Outside, their enhancements grant them a chance for a better life.
But few live long enough to enjoy it.Dirt Dweller Myla wasn't chosen to be a Decemite. But she still carries the nanobots in her blood-a secret she has revealed only to a chosen few. When Myla's young sister disappears after her first mission Outside, Myla must leave the safety of her dome to find her. Lock, a Decimite champion, joins Myla on her journey. But as they venture across the perilous wasteland, they meet Ben, a human living beyond the dome.
This young rebel shows Myla that life Outside is nothing like what she was told. To find her sister, she'll need both Ben and Lock's help. But if Lock discovers the secret hiding in Myla's blood, the penalty is death.