Merb was started two years ago by Ezra Zygmuntowicz as a tiny framework to serve ERb templates from Mongrel. This quickly grew into much more and carved out a niche as an alternative Rails stack. Merbists focused on among other things a small speedy core, being ORM/JavaScript agnostic, and having a rigorous API for extensions.
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On December 23rd, we decided to end the duplication and the paradox of choice. That was the day we declared our intentions of bringing the best ideas of Merb into Rails 3.
Rails 3.0 sera la prochaine version après la 2.3, qui n’est pas loin de sortir.