Directory

Open Source Packages

Libraries, frameworks, tools, and SDKs used by the apps in this directory — scored the same way as the apps themselves.

5929 packages

All Packages

98Health
Library npm

React

The declarative, component-based JavaScript library for building fast, interactive user interfaces on the web and in native apps.

250,786
MIT
Used by 407
98Health
Library npm

React DOM

React's official renderer for the DOM and server — createRoot, hydrateRoot, and streaming SSR in one package.

250,786
MIT
Used by 402
92Health
Framework npm

Playwright

Cross-browser end-to-end web testing and browser automation with a single API for Chromium, Firefox, and WebKit.

96,772
Apache 2.0
Used by 229
78Health
Library npm

dotenv

Loads environment variables from a .env file into process.env for Node.js apps.

20,543
Other
Used by 227
78Health
Library npm

date-fns

Modern JavaScript date utility library with 200+ pure, immutable functions

36,647
MIT
Used by 202
89Health
Library npm

jsdom

A pure-JavaScript implementation of the WHATWG DOM and HTML standards for Node.js.

21,692
MIT
Used by 200
64Health
Library npm

React Testing Library

Simple and complete React DOM testing utilities that encourage good testing practices.

19,655
MIT
Used by 196
67Health
Library npm

Lodash

A modern JavaScript utility library delivering modularity, performance, and extras for arrays, objects, and functions.

61,278
MIT
Used by 194
94Health
Library npm

Axios

Promise-based HTTP client for the browser and Node.js with interceptors, automatic transforms, and cancellation

109,216
MIT
Used by 190
65Health
Library npm

jest-dom

Custom Jest matchers for asserting on the state of the DOM in your tests.

4,598
MIT
Used by 166
94Health
Library npm

@babel/core

The core JavaScript compiler that transforms next-generation syntax into code every browser and runtime can understand.

44,022
MIT
Used by 163
85Health
Framework npm

Express

The fast, unopinionated, minimalist web framework for Node.js

69,493
MIT
Used by 158
89Health
Library npm

DOMPurify

DOM-only, uber-tolerant XSS sanitizer for HTML, MathML, and SVG that runs in the browser and on the server.

17,413
Apache 2.0
Used by 135
93Health
SDK npm

posthog-js

The official browser SDK for PostHog — autocapture, session replay, feature flags, and surveys in one drop-in script.

614
Other
Used by 133
94Health
SDK npm

AWS SDK for JavaScript (S3 Client)

The official modular AWS SDK v3 client for Amazon S3, with TypeScript-first APIs and streaming support.

3,668
Apache 2.0
Used by 129
91Health
Library npm

Recharts

A composable charting library for React, built on D3 and SVG.

27,594
MIT
Used by 127
91Health
Library npm

TanStack Table

Headless, type-safe tables and datagrids for React, Vue, Solid, and more.

28,461
MIT
Used by 117
84Health
Library npm

ws

A simple, blazing-fast, thoroughly tested WebSocket client and server library for Node.js.

22,807
MIT
Used by 116
77Health
Library npm

user-event

Simulates the full sequence of real browser events so Testing Library tests behave the way an actual user does.

2,330
MIT
Used by 116
95Health
SDK npm

Sentry JavaScript (@sentry/browser)

The official Sentry SDK for capturing errors, performance traces, and session replays in browser JavaScript apps.

8,745
MIT
Used by 110
82Health
Library npm

i18next

The internationalization framework for JavaScript, with zero runtime dependencies and a pluggable ecosystem for every environment.

8,637
MIT
Used by 110
90Health
Library npm

sharp

High-performance Node.js image processing powered by libvips, built for fast resizing and format conversion.

32,726
Apache 2.0
Used by 109
92Health
Library npm

AI SDK

Provider-agnostic TypeScript toolkit for building AI apps and agents with any LLM.

26,955
Apache 2.0
Used by 105
72Health
Library npm

Chalk

The most popular Node.js library for styling terminal string output with ANSI colors.

23,319
MIT
Used by 98

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