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

97Health
Tool npm

TypeScript

A strongly typed superset of JavaScript that compiles to clean, portable JavaScript.

111,050
Apache 2.0
Used by 500
98Health
Library npm

React

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

250,443
MIT
Used by 404
98Health
Library npm

React DOM

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

250,443
MIT
Used by 399
95Health
Tool npm

ESLint

The pluggable JavaScript and TypeScript linter that finds and fixes code problems through a fully customizable, plugin-based rule engine.

27,504
MIT
Used by 368
91Health
Tool npm

prettier

An opinionated code formatter that enforces consistent style across every language your project speaks.

52,263
MIT
Used by 310
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.

28,972
MIT
Used by 277
94Health
Tool npm

typescript-eslint

The official meta-package bundling the TypeScript ESLint parser, plugin, and rule presets behind a single typed config() helper.

16,391
MIT
Used by 260
92Health
Framework npm

Playwright

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

96,127
Apache 2.0
Used by 228
74Health
Library npm

dotenv

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

20,536
Other
Used by 227
92Health
Library npm

lucide-react

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

24,510
Other
Used by 220
93Health
Tool npm

@vitejs/plugin-react

The official Vite plugin for React with Babel-powered Fast Refresh and JSX transforms

1,158
MIT
Used by 209
68Health
Library npm

date-fns

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

36,648
MIT
Used by 202
93Health
Library npm

jsdom

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

21,681
MIT
Used by 199
65Health
Library npm

React Testing Library

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

19,651
MIT
Used by 195
76Health
Library npm

Lodash

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

61,278
MIT
Used by 194
95Health
Library npm

Axios

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

109,212
MIT
Used by 190
92Health
Library npm

TanStack Query

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

50,296
MIT
Used by 182
75Health
Library npm

Radix UI

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

19,268
MIT
Used by 181
86Health
Tool npm

tsx

A drop-in replacement for the node CLI that runs TypeScript and ESM files instantly, powered by esbuild.

12,141
MIT
Used by 177
69Health
Tool npm

eslint-config-prettier

Disables ESLint stylistic rules that conflict with Prettier, so the two tools never fight over formatting.

5,893
MIT
Used by 169
95Health
Framework npm

React Router

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

56,573
MIT
Used by 165
66Health
Library npm

jest-dom

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

4,597
MIT
Used by 165
64Health
Library npm

react-markdown

Safely render Markdown as React elements, no dangerouslySetInnerHTML required

15,878
MIT
Used by 164
95Health
Library npm

@babel/core

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

43,996
MIT
Used by 163

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