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Evented is the new hotness. It simplifies concurrent programming. Right? Not always. Tools like EventMachine and Node are fast, but are they always the right tool? And do they make your code easy to understand and modify?
Enter JRuby, the super-charged Ruby implementation that has all of Java's strengths, and none of its weaknesses. Among its strengths is a fully-armed and operational threading model that, a long with a few simple built-in libraries, can make concurrent code easy to write, easy to understand, easy to maintain, and just as performant as the evented version.
Why limit yourself to one way of solving problems? This talk will arm you with an alternative for handling concurrency: JRuby and Threads.