An anonymous reader writes "While it almost certainly remains the largest Ruby on Rails based site in the world, Twitter has gradually been moving more and more of its stack to the JVM.
From the article:
We were originally a Rails shop, and I believe we are the largest Rails site in the world, but as we've grown as an organization, and as a service, performance and encapsulation have become very critical. I wouldn't say that Rails has served as poorly in any way, it's just that we outgrew it very quickly. So there are two things about Rails that make it no longer ideal for our situation."
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