It's defined in their (somewhat oddball) version policy: "MINOR: increased every christmas, may be API incompatible"[1] [1]: https://www.ruby-lang.org/en/news/

It's defined in their (somewhat oddball) version policy: "MINOR: increased every christmas, may be API incompatible"[1] [1]: https://www.ruby-lang.org/en/news/2013/12/21/ruby-version-policy-changes-with-2-1-0/ https://www.ruby-lang.org/en/news/2013/12/21/ruby-version-po...