I just read this and really enjoyed it.
I'm used to there being two kinds of science fiction. There's the kind with lots of tech, character development minimal, at worst all the characters are essentially muscle heads that can do tech. The women, if there are any, are bimbos or someone's mother. Then there's the kind with a lot less tech and a lot more character, usually they have the strange societies with back stories that are more reminiscent of fantasy than science fiction.
This one falls into the tech end, it is one of the most techy science fiction reads I've come across. There are numbers. How long before a man stranded on Mars runs out of air? How about water? How about food? How much current does this device he's working on draw? How much do the solar panels produce? How much should they produce and why is it different? Boring? No way! This is an edge of your seat thriller you read later than you should into the night and hope to cram in another chapter over breakfast.
And we have characters as well. The guy on Mars feels real. He's smart (a lot smarter than I am) but he screws up and struggles to stay alive. Often. Then there are the people back on Earth who become aware of the situation and go to huge lengths to try and get him back. And they're smart too, but they screw up. How do they keep him alive long enough to have a hope of rescue? Or maybe just keeping him alive a bit longer is the best they can do? Some of them are girls too. Gosh.
The author, Andy Weir, is a software developer, as am I. And in the constant ebb and flow of trying solutions, things going wrong, fixing them good, or just patching them up I found some familiarity. Nothing I build goes to Mars, of course, but building complicated stuff and making it work is perhaps always a bit like this.
I see they're making a movie. I want to see it. Meanwhile read the book.