Ada Hoffman's The Outside is a fine debut novel that throws together several different popular modern tropes into a lovely stew of a novel, but it also suffers from the big problem faced by all writers in this space, myself included.
[Warning, there be spoilers!]
The Outside is a novel that combines two classic conceits: humans surviving somehow in a post "hard liftoff" universe (one in which AIs achieve sentience, discover their own path to self-improvement, and transform themselves into godlike beings), and humans surviving in a universe where our reality is one of many, embedded in a multiverse that itself has creatures of incomprehensible power and who are attracted to our experiments with extreme physics.
The first is very much like Charlie Stross's Eschaton series, but there's a twist: the AIs fail to be creative in some fundamental way and if they don't "get" creativity they stagnate and fade away. In The Outside, the surviving AIs of the "first war among the gods" become the gods of humanity, overseeing human civilization and limiting human civilization to a fairly high-tech but constrained existence, in exchange for rendering the human soul at the time of natural death, thus "consuming" the creativity the Gods need to survive. In exchange, the Gods of The Outside provide interstellar travel, defenses against alien civs, and protection against the titular Outside.
The second is that Outside. The reason the gods limit human sciences is that advanced symbologics attract the curiosity of these beings from the universe next door. Unlike Charlie Stross's Laundry series, these beings are not really inimical. They don't hate us, and they don't want to eat us. Instead, they're more like… what we do attracts their attention the way the symmetry of a line of ants marching attracts our eye, but usually only children want to see what what happens if they mess with the ants. The Outside is still so weirdly different, so anti-reality, that looking at them tends to cause madness in ordinary humans.
That's the setting. It's genuinely a Weird Fiction setting, and its strength is in its characters: Yasira, the main protagonist, who accidentally unleashes an "Outside incident" on her homeworld; the Angel in charge of investigating the incident, a shapeshifting psychopath who has to deal with the hierarchy of angels even as he hunts down the main antagonist; and Yasira's mentor and the actual cause of the incident, who seems to have made contact with the Outside and learned how to deal with them, which makes her insanely dangerous.
The adventure of the book is pretty good. Like all books in this trope, the ending is… laced with incomprehensibility. With post-human AIs on one side and transcendentally Weird creatures on the other, the culmination of the story has to be taken on faith. The heroes Did Something, and have to live with the consequences. We don't understand what they did, but in the end humans survive, our characters are "changed" in interesting character ways, there's no happily ever after, and there's enough leftover for maybe a sequel.
If there's a quibble with the book, it's that Yasira's autism is treated as a superpower, her focus on math and physics, her attention to detail, and her inability to get along with others. There's a hint in the book that some forms of neurodiversity allow people to see "the Outside" naturally, can see that reality isn't as neatly, cleanly linear and temporal as ordinary consciousness, and the Gods, want us to believe. Hoffman does okay emphasizing the alienation that "superpower" brings. I guess I just worry about this sort of representation: pandering to my self-deprecating jokes about my superpower doesn't override the alienation I've felt my whole life, "not getting it" about anything "normal people" are doing.
It's a good book, especially for a debut. I haven't decided yet whether or not to read the sequel. It didn't feel like there was more to tell, and the conflicts left at the end of the book felt petty against the world-threatening scale of the climax.