Fundamental Magics. The Ruins of Gandarah, #1

In a world where magic is returning after centuries of absence, Professor Adrienne Imlay has been able to balance her secret shamanic abilities with her academic career. But when she becomes entangled with Philidor Magnus, a charismatic inventor with a dark secret, she is drawn into a deadly plot involving demons, rival industrialists, and shadowy magical authorities. When rifts to other dimensions threaten to tear her city apart, she must confront her own abilities and the ethical quandaries they pose. A special note for readers: this book contains a lot of different characters and a lot of worldbuilding.
If you prefer your settings conventional and your story focused on a few heroes and villains, you probably won't enjoy this novel.