Development-only error handler middleware for Express.js applications with comprehensive error formatting and content negotiation.

Fast encoder and decoder for the Erlang Term Format (version 131) for JavaScript

Basic DOM manipulation library providing type-safe API for working with DOM elements, events, and properties

Shallow equality comparison utility function adapted from React's shallowEqual implementation

React 16.x adapter for Enzyme testing library that enables shallow rendering, full DOM mounting, and static markup rendering of React components.

Command-line tool and library for collecting development environment information needed for debugging and troubleshooting software issues

Validation for your environment variables

Get paths for storing things like data, config, cache, etc

Executes a command using the environment variables in an env file

Encode & decode XML and HTML entities with ease & speed

Stylish, intuitive and user-friendly prompt system for creating interactive CLI interfaces

Awesome Media Queries in JavaScript

Highly configurable async require.resolve function with extensive customization options for module resolution

The realtime engine behind Socket.IO providing bidirectional connection foundation between client and server

Parser for the engine.io protocol encoding, handling packet and payload encoding/decoding with binary support

Client for the realtime Engine providing bidirectional communication with WebSocket, polling, and WebTransport support

Call a callback when a readable/writable/duplex stream has completed or failed.

Secure URL encoding utility that safely encodes URLs to percent-encoded form while preserving already-encoded sequences

Framework-agnostic CSS-in-JS library for generating styles, animations, and global CSS

A memoization function that uses a WeakMap for efficient caching based on object identity