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
91Health
Library npm

Zod

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

43,990
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
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
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
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
86Health
Framework npm

Express

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

69,454
MIT
Used by 158
82Health
Tool npm

esbuild

An extremely fast JavaScript and CSS bundler and minifier written in Go.

40,058
MIT
Used by 139
90Health
Library npm

DOMPurify

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

17,387
Apache 2.0
Used by 135
91Health
Library npm

React Hook Form

Performant, flexible React forms built on hooks with minimal re-renders and built-in validation.

44,855
MIT
Used by 132
93Health
SDK npm

posthog-js

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

607
Other
Used by 132
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.

3,666
Apache 2.0
Used by 129
91Health
Library npm

Recharts

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

27,555
MIT
Used by 127
62Health
Tool npm

eslint-plugin-react

React-specific linting rules for ESLint that catch JSX bugs, enforce Hooks conventions, and keep prop usage consistent.

9,292
MIT
Used by 122

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