Last Gifts of the Universe, by Riley August (hardcover)

 A dying universe. A search for answers. An adventure at the end of a trillion lifetimes.

When the Home worlds finally achieved the technology to venture out into the stars, they found a graveyard of dead civilisations. What befell them is unknown. All Home knows is that they are the last ones left – and whatever came for the others will one day come for them.

Scout is an Archivist who scours the dead worlds of the cosmos for their last gifts: interesting technology, cultural rituals – anything left behind that might be useful to Home and their survival. During an excavation on a lifeless planet, Scout unearths something unbelievable: a surviving message from an alien who witnessed the world-ending entity thousands of years ago.

Now Scout, their brother and their sometimes-fearless, space-faring cat, Pumpkin, must race to save what matters most.