Sexy.js is a lightweight (<1kb compressed) JavaScript library that provides enhanced sequential Ajax (Sajax) functionality.

Sequential Ajax is an Ajax pattern for handling multiple asynchronous requests while maintaining proper callback execution order.

The library is chainable, enables you to manage script dependencies and write prettier code.

Sexy.js

It comes in 2 versions: standalone or as a jQuery plugin.

There is a slideshow on Sexy.js that provides the cons and pros of it in details:

WebResourcesDepot Feed