Engineers manual, Service issue

By the year 2132 Humanity has spread across the galaxy, but Earth has been left in ruin.
War rages on Earth though not by humans hands but through War Machines.
Engineers trained and hardened are sent back to Earth to maintain the Machines code.
After a fatal landing join the Engineer Ferin as he discovers that not all the Machines wish for humanity to reclaim their ancient home.

Please Note: This is the first book in a planned trilogy with the first and second book mostly completed however writing of the third hasn't started yet