EventMachine is a simple(ish), fast, event-driven I/O library for Ruby. Its goal is to provide highly scalable I/O performance with an easy-to-use API wrapped around the nastiest parts of the process (since typical Ruby coding practices aren’t particularly event-driven friendly). Aman Gupta has put together an awesome 114-page deck of slides (also available as a PDF) that walks through EventMachine with lots of practical code examples.

The presentation walks through:

  • Who uses EventMachine (a lot of big guys – Heroku, GitHub, 37signals, Engine Yard, PostRank)
  • What EventMachine is good for
  • Ruby’s other I/O solutions (and why they suck)
  • What a “reactor” is
  • How to write asychronous code with EventMachine’s API
  • How EventMachine provides event-compatible iterators and timers
  • EventMachine’s message channels

Even though Aman’s slides are meant to go alongside a live presentation, they stand well on their own and provide more than enough incentive to check out EventMachine is event-driven I/O is something that would benefit you, so stop reading this post and get flicking through Aman’s awesome slides!