If you want to read up on how Github transitioned, this post is useful: <a href="http:&#x2F;&#x2F;shayfrendt.com&#x2F;posts&#x2F;upgrading-github-to-rails-3-with-zero-downtime&#x2F;" rel="nofollow">http:&#x2F;&#x2F;shayfrendt.com&#x2F;posts&#x2F;upgrading-github-to-rails-3-with...</a><p>Getting stuck on 2.3 isn&#x27;t desirable.