title: Ruby non-blocking libraries vs Node
body: <p>I'm evaluating Ruby EventMachine (and similar non-blocking frameworks such as Cramp) vs Node.js.  I've worked with Node before, but have never worked with EventMachine.  One of the ideas that Ryan Dahl encourages is that the ecosystem of libraries in javascript have to be similarily non-blocking in order promote this.  This is part of the reason why Node was developed from the ground up.</p>
  
  <p>My question is, can you get far in Ruby without blocking?  My assumption is that EventMachine alone is often not enough to build a complete web application stack.  If so, what other libraries in Ruby promote non-blocking IO (ie for database/filesystem/http access)?</p>