Core Data

Raised as a usability problem by 6 people on Hacker News over 3 years (2012–2014), in 5 threads.

People raised many different problems with Core Data, 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 6 complaints

Core Data concepts are too low-level and opaque, forcing developers to copy code snippets2014-06-03
Getting usable model objects needs a lot of manual work2013-10-15
Core Data over iCloud and migration models are described as warts2013-06-11
Multithreaded Core Data setup is undocumented and requires trial-and-error learning2013-03-28
Developers must write heavy boilerplate and struggle with thread-safe concurrency and awkward queries2013-03-28
Child contexts over-release objects on cleanup, and error messages are unhelpful2012-07-07