John Mark Ockerbloom on Nostr: I can think of a few, including this project of mine (we've finished the ...

I can think of a few, including this project of mine (we've finished the pandemic-closures phase that involved a lot of library workers' paid time, but we're still accepting input from the public via forms, and the knowledge base continues to be maintained and grow slowly): https://onlinebooks.library.upenn.edu/cce/db/

I've also heard from a number of folks in and around libraries who work on Wikidata and related metadata efforts. There's a related affinity group that meets weekly: https://www.wikidata.org/wiki/Wikidata:WikiProject_LD4_Wikidata_Affinity_Group