The Sunlit Man

A Bridge 4 soldier from the Stormlight Archive is skipping across the Cosmere and ends up on a planet whose sun destroys (nearly) all life it touches. The planet's inhabitants live in cities that are made up of a bunch of conjoined hovercraft that keep the people moving perpetually within the safety of night.

The soldier joins up with a small group of revolutionaries as they seek out a refuge that would allow them to stop constantly moving while resisting an evil dictator who wants to unify/enslave all the planets inhabitants.

As a story the book was fine, but I had a hard time accepting the setting. I wouldn't expect life to have been viable on a planet where the sunlight destroys what it touches, yet somehow there are indigenous animals that live there (mentioned only briefly). The humans living there aren't native, but assuming some of the people that decided to go there survived the discovery of the sun's destructive power, its unclear why they didn't immediately pack up for somewhere better.

Also, a major plot point was the need to get the rebel city to fly over some mountains to avoid having to fight the dictator's forces, and through a major engineering effort, that is accomplished. A secondary project was to build weapons for the city so that they could fight the dictator. It seems like if they had made the weapons the primary project, they could have skipped the "fly over the mountains" project entirely.

Given the number of pre-release readers Brandon Sanderson has for his books, I have to think that it all made sense to lots of people, but I guess I missed that understanding beyond "magic". Or maybe Brandon just liked the setting and didn't want to get bogged down in justifying it, thereby ruining the story.