Be careful about becoming an expert. Maybe being "good enough" is a better investment of your time. I once wrote a business-facing app in ExtJS. I played aroun

Be careful about becoming an expert. Maybe being "good enough" is a better investment of your time. I once wrote a business-facing app in ExtJS. I played around with it, and I said, "ExtJS is cool, I am going to get good at it". Six months of studying the dark corners of ExtJS and becoming really good at performance challenges and corner cases, ExtJS comes out with version 4, burning the bridges with new paradigms and making my "expertise" obsolete. In general, stick to micro-frameworks. It's much harder to get burned in that world.