Post Human series, 5 books, by David Simpson.
The future should have been perfect. Microscopic robots known as nans could repair any damage to your body, keep you young by resetting your cellular clocks, and allow you to download upgrades like intelligence, muscle strength, and eyesight. You were supposed to be able to have anything you wanted with a simple thought, to be able to fly without the aid of a machine, to be able to live forever. But when a small group of five terraformers working on Venus return to Earth, they discover that every other human in the solar system has been gruesomely murdered. Now, James Keats and his four companions must discover what happened to the rest of humanity and fight back if they wish to avoid the same, horrifying fate. Welcome to the post-human era.
Here’s a series I wish I hadn’t started.
It was painful to make myself finish it.
Great premise, great ideas re AI, but poor writing and terrible characterization.
I stuck with this hoping each additional book would redeem the series.