Why Ruby app servers break on macOS High Sierra and what can be done about itAbout us Founded in 2008, Phusion creates top of the line server software to power businesses like Apple and Intercom. People who have upgraded to macOS High Sierra and who are using a preforking app server such as Puma or Unicorn (with the right settings), may have noticed this error: objc[81924]: +[__NSPlaceholderDictionary initialize] may have been in progress in another thread when fork() was
