Ivar is a Ruby gem that automatically checks for typos in instance variables.That’s because what Ivar does seems so basic that it’s almost a surprise it isn’t part of the language. Do you see that warning about an unkown instance variable? That’s ...

YARV: Yet Another RubyVM was started in January 2004 to speed up the execution of Ruby, and YARV is still running in your Ruby today as the core of Ruby.In t...