When your gems complain about invalid gemspecs and illformed requirements, it is most probably an error resulting from the transition from Syck to psych Show archive.org snapshot . To fix this:

1. go to your gemspec directory (e.g. /Library/Ruby/Gems/1.8/specifications/)
2. change #<Syck::DefaultKey:0x00000100e779e8> to = (equals sign) in each file that's complaining

Rails Long Term Support

Rails LTS provides security patches for old versions of Ruby on Rails (2.3, 3.2, 4.2 and 5.2)

• Prevents you from data breaches and liability risks
• Upgrade at your own pace
• Works with modern Rubies

Read more Show archive.org snapshot