[hkarthik]

While I agree that you probably miss out on finding a lot of great candidates, there is a significant advantage in finding someone that already knows your chosen platform.

Already knowing the OS and Tools allows a new hire to focus on understanding the business domain quickly. For some companies, that's far more important than raw technical ability.

[ulf]

The "quickly" argument is a strawman, if you plan on having a working relationship that lasts longer than 3 months or so. If you just need someone to upgrade your current Rails 2.3.8 project to 3.0.6 and then move along, by all means get someone with Rails experience.

But if you intend to employ that person longer, the specific experience is of diminishing importance.

[phamilton]

That's why I usually try to describe myself as a bard of programming. Pick a language. Pick a framework. I know enough to get started, and I know where to find answers to my questions.