There's nothing new under the sun? It does have a Total Recall feel.
Most fiction borrows or builds on what came before it, with twists and interpretations that make it unique. It becomes harder and harder to think of something nobody has ever done before when you continually add to both the number of people creating things and the time they have been creating them. If you add the laws of physics in there, however loosely, there are only so many ways you can terraform without going completely alien or deux ex machina.
You have to have machines (something autonomous, capable of function in hostile environment, self repairing/replicating, doesn't care about time or scale) that do something, and on a gigantic scale (even if they were nanomachines), and they have to get power/material from somewhere. It is going to be advanced alien to us - if some undiscovered race did it and since we cannot do it ourselves.