Realm

Raised as a usability problem by 4 people on Hacker News over 4 years (2014–2017), in 3 threads.

People raised many different problems with Realm, but no single problem has yet been raised by 3 people in 3 different months and threads.

Unreviewed issues were grouped by machine: Claude Haiku labelled each comment as a usability complaint, named what it's about and summed up the problem in a line, and a small model grouped similar problems. Nobody has checked them by hand. Expect mistakes.

The newest 4 complaints

Can't find a feature list or docs covering schema, query language or ACID; docs are sparse and disorganized2017-02-07
Change notifications don't say what was modified, only that an object changed somehow2017-02-06
Docs fail to make the cross-thread sharing requirement clear up front2016-05-25
Can't instantiate RealmObjects from JSON; must use createObject, making it hard to use2014-09-30