- debug
small debugging utility
- qs
A querystring parser that supports nesting and arrays, with a depth limit
- moment
Parse, validate, manipulate, and display dates
- semver
The semantic version parser used by npm.
- ws
Simple to use, blazing fast and thoroughly tested websocket client and server for Node.js
- fs
- readable-stream
Streams3, a user-land copy of the stream library from Node.js
- crypto
- cheerio
Tiny, fast, and elegant implementation of core jQuery designed specifically for the server
- Top 12 Jupyter Notebook extensions