[kondro]

People keep comparing this to Bluebird, which is great and all, but Bluebird's JS is 72KB minified, whereas this library is just 3KB.

That's what makes this a "small" JavaScript library for managing asynchronicity. And when you're using it for things like choosing which ads to display, etc (like some of the examples) you really don't want your JS load overhead to be very high.

[hiddentao]

That's true, but given the gradual shift to ES6 features over time you're more likely to end up using something like Bluebird (e.g. to complement your generators) and so having another library to then handle asynchronicity (and that too with callbacks) would be redundant.