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
90Health
Library npm

Tailwind CSS

A utility-first CSS framework for rapidly building custom user interfaces without leaving your markup.

97,713
MIT
Used by 342
92Health
Library npm

Zod

TypeScript-first schema validation with static type inference and zero dependencies.

44,052
MIT
Used by 277
92Health
Library npm

postcss

A CSS transformation engine that parses styles into an AST, letting JS plugins lint, prefix, and rewrite CSS — the foundation beneath Autoprefixer, Tailwind, and 200+ other tools.

28,977
MIT
Used by 277
42Health
Library npm

clsx

A tiny, fast utility for conditionally constructing className strings

9,844
MIT
Used by 257
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
92Health
Library npm

lucide-react

1,700+ tree-shakeable, customizable SVG icon components for React applications

24,747
Other
Used by 222
86Health
Library npm

tailwind-merge

Merge Tailwind CSS classes without style conflicts

5,692
MIT
Used by 219
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
87Health
Library npm

Autoprefixer

Parses your CSS and automatically adds vendor prefixes using real-world browser usage data from Can I Use.

22,225
MIT
Used by 198
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
82Health
Library npm

class-variance-authority

A tiny TypeScript utility for building type-safe, variant-driven className APIs on top of clsx.

6,901
Apache 2.0
Used by 191
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
92Health
Library npm

TanStack Query

Hooks-based async state management for fetching, caching, and syncing server data in React.

50,368
MIT
Used by 183
74Health
Library npm

Radix UI

Unstyled, accessible React UI primitives for building your own design system.

19,339
MIT
Used by 182
69Health
Library npm

uuid

RFC9562-compliant UUID generation for JavaScript and TypeScript.

15,334
MIT
Used by 172
95Health
Framework npm

React Router

A multi-strategy router for React, from a lightweight library to a full SSR framework.

56,590
MIT
Used by 167
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
66Health
Library npm

react-markdown

Safely render Markdown as React elements, no dangerouslySetInnerHTML required

15,892
MIT
Used by 164
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

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