You mentioned performance and packaging. There's also concurrency issues but those are improving. The most interesting critique of Ruby I've heard recently wa

You mentioned performance and packaging. There's also concurrency issues but those are improving. The most interesting critique of Ruby I've heard recently was from Tom Stuart @ Ruby Manor this year: http://lanyrd.com/2013/ruby-manor/scffpd/ http://lanyrd.com/2013/ruby-manor/scffpd/ In this talk he demonstrated how the multi-paradigm nature of Ruby makes it hard to fully realize the benefits of a single paradigm like FP or OOP. This is obviously not something that CTOs are bringing up in tech provisioning discussions, but I think it does prevent ruby from having the kind of strengths that would make it a go-to language for certain types of projects the way that Go, Scala, Node.js or Haskell are able to do these days. I think Ruby's biggest appeal is to programmers who care a great deal about aesthetics and expressiveness of code.