- qs
A querystring parser that supports nesting and arrays, with a depth limit
- commander
the complete solution for node.js command-line programs
- winston
A logger for just about everything.
- moment
Parse, validate, manipulate, and display dates
- async
Higher-order functions and common patterns for asynchronous code
- bluebird
Full featured Promises/A+ implementation with exceptionally good performance
- mkdirp
Recursively mkdir, like `mkdir -p`
- postcss
- readable-stream
Streams3, a user-land copy of the stream library from Node.js
- Top 12 Jupyter Notebook extensions