Merb is a more modular Ruby framework than Rails, with a smaller core and an emphasis on performance. Today EngineYard announced the first major release of its free open source framework, Merb. According to EngineYard,Merb is designed for building fast, high performance Ruby applications. Similar to Ruby on Rails, Merb is an MVC framework but it features a modular — rather than monolithic — architecture with minimal, clean core code that is simple, organized, and easy to extend.I spoke with Yehuda Katz, a Merb project developer and maintainer at EngineYard, about this announcement.“Merb was originally created to solve some Rails file upload issues, although those are no longer problems in Rails. As we developed Merb, we concentrated on performance and modularity. Rails comprises about 80 thousand lines of code; the Merb core module is only 6 thousand lines of code. There are other modules; you can use as many or few of them as you like. Merb is much faster than Rails at returning responses to simple requests, and much easier to understand and customize.” While one of the selling points of Merb is its portability, I discovered firsthand by trying to install the Merb gem that the Windows implementation is not quite cooked at this point. I reported the problem to Katz, and he promised that it would be addressed in the next three weeks. “You’re not the only developer interested in Merb on Windows, but most of our testers have been using Mac OSX or Linux. Supporting Windows is definitely one of our goals for the 1.0 release at the end of October.”According to Katz, Merb should be interesting to small design shops; to developers who are unable to get past the 80 percent point on their Rails applications; and to hackers who want to customize the framework. Merb should also be interesting for applications where Web response time is an issue. Software Development