2,5* - it was OK.
Be aware that this book is more on the drama side than sci-fi. Traumatic memories, difficult past, greedy corporation, a lone hero... this kind of stuff. "Haker" part is rather naive and simple. As well as the plot which allows you to be two steps ahead of the main characters. Still, some readers might like it, as it is not that bad and the initial idea is interesting.
Have in mind, that this is the first part of the series, so you won't get a lot of answers with the last page.