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

93Health
Tool npm

Vitest

A blazing-fast unit testing framework powered by Vite, with Jest-compatible APIs out of the box.

17,166
MIT
Used by 296
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

date-fns

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

36,647
MIT
Used by 202
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
95Health
Tool npm

jest

Delightful JavaScript testing with zero-config setup, snapshots, mocking, and coverage

45,465
MIT
Used by 149
78Health
Library npm

Zustand

A small, fast React state management library with a hook-based API and no boilerplate.

58,763
MIT
Used by 119
78Health
Tool npm

eslint-plugin-import

ESLint rules that validate ES module import/export syntax and catch broken paths before they hit your build.

5,947
MIT
Used by 116
94Health
Library npm

Marked

A fast, low-level Markdown compiler that parses CommonMark and GFM into HTML in Node.js, browsers, or the CLI.

37,214
MIT
Used by 112
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
96Health
Framework PyPI

pytest

The Python testing framework that makes writing small tests easy and scales to complex functional test suites.

14,543
MIT
Used by 100
85Health
Library npm

@hookform/resolvers

Official React Hook Form adapters that plug 20+ schema-validation libraries — Zod, Yup, Joi, Valibot, ArkType and more — straight into useForm's resolver.

2,263
MIT
Used by 93
58Health
Library npm

node-fetch

A lightweight, spec-compliant implementation of the browser Fetch API for Node.js

8,855
MIT
Used by 74
86Health
Library npm

highlight.js

Zero-dependency JavaScript syntax highlighter with automatic language detection for over 190 languages.

24,999
BSD 3
Used by 73
85Health
Library npm

Floating UI

React hooks and components for building accessible, perfectly positioned tooltips, popovers, and dropdowns.

32,753
MIT
Used by 68
56Health
Tool npm

eslint-plugin-jsx-a11y

Static ESLint rules that catch JSX accessibility issues before code ships.

3,621
MIT
Used by 65
90Health
Library npm

React Email

High-quality, unstyled React components for building responsive HTML emails

19,788
MIT
Used by 51
90Health
Library npm

Cheerio

The fast, flexible library for parsing and manipulating HTML and XML with a familiar jQuery-style API.

30,505
MIT
Used by 45
86Health
Library PyPI

PyJWT

A Python implementation of RFC 7519 for encoding, decoding, and verifying JSON Web Tokens.

5,706
MIT
Used by 44
95Health
Framework PyPI

aiohttp

Asynchronous HTTP client and server framework for Python's asyncio, covering both API calls and building web/WebSocket services.

16,561
Apache 2.0
Used by 40
95Health
Framework PyPI

Transformers

State-of-the-art pretrained models for text, vision, audio, and multimodal inference and training.

166,736
Apache 2.0
Used by 38
93Health
Tool npm

Cypress

Fast, easy, and reliable end-to-end and component testing for anything that runs in a browser.

51,026
MIT
Used by 38
92Health
Library npm

Tauri Plugin FS

Cross-platform file system access for Tauri apps through a typed JavaScript API backed by Rust.

1,817
Other
Used by 38
61Health
Library npm

react-colorful

A tiny, dependency-free color picker component for React and Preact apps

3,557
MIT
Used by 37
92Health
Framework npm

Docusaurus

React-based static site generator for building fast, maintainable documentation websites.

66,349
MIT
Used by 36

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