Fan wikis for science fiction series
Each wiki here is a fan-made guide to one series: its characters, species, places and technology. Every page says which book a fact comes from, so you can read without being spoiled by later books.
Children of Time Fan Wiki
Adrian Tchaikovsky's Children of Time series: all four books, with pages for characters, species, places, technology, factions and ideas.
More wikis will be listed here when they exist.