This can be an issue if you aren't able to pick up new skill sets quickly. As another poster said languages and frameworks are tools. While you can't be a mast

This can be an issue if you aren't able to pick up new skill sets quickly. As another poster said languages and frameworks are tools. While you can't be a master at a new language in a week you can certainly become functional in it. I always look to hire people with general aptitude for technology not just in one language even if they only work in that one language. There are always going to be people who learned one language or framework and they cannot apply that to any new endeavor, like wise there are folks who pick up new things easily. Conceptually everything we do falls into a few categories and as long as you know whats possible then determining the way you do X with that tool is the only challenge.