Packs CommonJs/AMD modules for the browser. Allows to split your codebase into multiple bundles, which can be loaded on demand. Support loaders to preprocess files, i.e. json, jsx, es7, css, less, ... and your custom stuff.
Higher-order functions and common patterns for asynchronous code
Full featured Promises/A+ implementation with exceptionally good performance
YAML 1.2 parser and serializer
Streams3, a user-land copy of the stream library from Node.js
The semantic version parser used by npm.
the complete solution for node.js command-line programs
Simplified HTTP request client.
Fast, unopinionated, minimalist web framework