I've never used it. My first thought is that $ label looks like callback hell, but without being able to step through the code easily to see where handlers are

I've never used it. My first thought is that $ label looks like callback hell, but without being able to step through the code easily to see where handlers are getting executed. Syntax wise I don't like it because it makes the whole thing look like a simple variable assignment. Something that might be an expensive call looks like something that's usually a cheap operation. Maybe I just think in terms of Java too much because it's the first language I learned, but I find all of the frameworks that use conventions like that hard to read. You need a ton of knowledge about how the internals work to understand what's happening in those scenarios. With Java, I always found the cost of writing boilerplate and declaring everything was paid back by how easy it was to read and follow existing code.