More Configurability, Modularity, Scalability
Merb is tuned for developers who want a higher degree of configurability and modularity than that offered by Rails, Katz said. And Merb allows developers working on smaller applications to replicate common Rails tasks with less overhead and a higher degree of customizability. Zygmuntowicz said:In addition, Merb is more apt to avoid one of the complaints about Ruby on Rails: its ability to scale, Katz said. "Merb is set to scale more efficiently," he said. "Rails can scale but requires more hardware." In a blog post on Merb, Mark Driver, an analyst with Gartner, said, "Everyone in the Ruby developer community is familiar with the growing pains of Rails. Scalability questions continue to run rampant as both the framework and the collective RoR community mature over time in real-world test cases." Zygmuntowicz said Merb is completely open source, "but we have a major company, Engine Yard, behind it, and we'll be providing it as part of our stack and offering support for it." Moreover, Zygmuntowicz said 95 percent of the applications hosted at Engine Yard are Rails applications and the other 5 percent are Merb applications. For his part, Driver said:
"Rails is the best thing out there for the 80/20 rule. It will get you through the first 80 percent [of an application] quickly, but then you will fight tooth and nail for that other 20. Merb may not be so fast for that first 80 percent, but the last 20 will be easier."
"Bottom line: Are you a RoR developer or the manager of a RoR developer? Then you owe it to yourself to check out Merb and keep an eye on it. You might like what you see enough to make a change. You probably won't today, but you may change your mind over the course of the next 18 months."Engine Yard officials said a key feature in Merb 1.0 is the "Merb Stack," a gem for fast, out-of-the-box deployment. This lets developers start building new applications immediately, rather than needing to spend time cobbling together a complete stack on their own. In addition, Merb 1.0 is built on a single master process rather than several disparate processes, which allows groups of Merb processes to share memory. This produces more efficient handling of multiple requests over short periods of time and better control over groups of Merb processes. To download the preview for Merb 1.0, go to http://merbivore.com/get_merb.html. The final Merb 1.0 release is targeted for the end of October.