The Book of M is her first novel.
One of Shepherd's five favorite books about magical apocalypses, as shared at Tor.com:
Where Futures End by Parker PeevyhouseRead about the other entries on the list.
This YA debut seamlessly weaves together the magic of fantasy and the technology of sci-fi into something completely its own. When a portal to another world suddenly opens, our own is irrevocably changed. But even as things on our side of the divide begin to take a turn for the worse, with rising inflation, uncontrollable global warming, and insidious new technologies, the mystical tether refuses to let go—and perhaps is not as benevolent as it first had seemed. The story has a fascinating structure; it’s told through the eyes of a series of linked protagonists, each several decades ahead of the previous. The potential futures Peevyhouse imagines in this book are at once bizarre, a little terrifying, and most of all, hauntingly possible.
--Marshal Zeringue