This was quite a good book, with lots of grand topics and epic feats as ordinary people struggle against the forces of nature. It has a decent set characters, though it changes part way, and there is no single main character across the whole story. In typical hard-scifi fashion, a lot of time is spent describing scientific concepts, such as orbital mechanics or genetics. I was OK with this, but your mileage may vary.

For a more in-depth review, check out my blog: strakul.blogspot.com/2019/07/book-review-seveneves-by-neal-stephenson.html