Posted by naruse on 24 Feb 2018 We are pleased to announce the release of Ruby 2.6.0-preview1. Ruby 2.6.0-preview1 is the first preview toward Ruby 2.6.0. This preview1 is released earlier than usual because it includes an important new feature, JIT. JIT Ruby 2.6 introduces an initial implementation of JIT (Just-in-time) compiler. JIT compiler aims to improve performance of any Ruby program execut