@juergen_hubert@thefolklore.cafe The only one I know is YaCy* https://yacy.net/, but I have never tried it.

Theoretically, you could build an engine with the Apache Lucene environment, and have its crawler component based on some kind of P2P networks, but that requires a whole lot of specialized technically expertise and probably cannot be done outside of major support infrastructure.

@juergen_hubert@thefolklore.cafe Storing is easy, the problem you face is organization: You will need to find the books you are looking for. That requires a search index, and probably some kind of tags. OpenLibrary has a thousands of volunteers for this and most of their entries are still rather bare-bones. I think this requires a more institutionalized approach than BookWyrm (which draws data from institutions like OpenLibrary and Worldcat).

@sbv @andrewrgross The starter scenario for Green Ronins Fantasy AGE / Dragon Age RPG should fit.