The basic reason behind my motivation is that I'm looking for a simple solution developed for the all javascript environments with no commonjs support, not only web browsers. Besides of it, it's better to have same dependencies in both backend and frontend, taking advantage of using NPM. Imagine a test script that should be run by both NodeJS and Internet Explorer 6. What is the current most low-cost way to do it?
Is there something that differentiates your approach? I do actually think there's room for improvement in these libraries, so I'm genuinely curious.