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

90Health
Tool npm

Oxlint

Rust-based JavaScript/TypeScript linter that runs 50-100x faster than ESLint, with zero configuration required.

22,902
MIT
Used by 70
85Health
Library npm

Floating UI

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

32,753
MIT
Used by 68
73Health
Library npm

MDX

The compiler that lets you write JSX directly inside Markdown documents

19,805
MIT
Used by 68
56Health
Library npm

classnames

A tiny utility for conditionally joining CSS class names together.

17,778
MIT
Used by 68
62Health
Library npm

Emotion

Performant, flexible CSS-in-JS styling for React with the css prop, theming, and SSR support

18,020
MIT
Used by 66
56Health
Tool npm

eslint-plugin-jsx-a11y

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

3,621
MIT
Used by 65
76Health
Library npm

React Icons

SVG icon components for React, bundling 40+ popular icon packs behind one consistent import syntax.

12,671
MIT
Used by 64
92Health
Library PyPI

Pillow

The friendly PIL fork that adds image processing capabilities to Python

13,856
Other
Used by 62
63Health
Library Cargo

url

A WHATWG-standard-compliant URL parser and manipulation library for Rust.

1,575
Apache 2.0
Used by 62
98Health
Library PyPI

pandas

The Python DataFrame library for fast, flexible, and expressive data analysis and manipulation.

49,851
BSD 3
Used by 61
79Health
Library npm

PapaParse

The fastest in-browser CSV parser for JavaScript, with streaming, Web Workers, and zero dependencies

13,576
MIT
Used by 61
91Health
SDK PyPI

boto3

The official AWS SDK for Python — call every Amazon Web Services API from your code.

9,909
Apache 2.0
Used by 60
97Health
SDK PyPI

OpenAI Python SDK

The official Python library for the OpenAI REST API, generated from OpenAI's OpenAPI spec with typed sync and async clients.

31,709
Apache 2.0
Used by 59
50Health
Library npm

React Syntax Highlighter

A React component for syntax-highlighting code blocks using highlight.js or Prism ASTs, with JavaScript-based styles and no external stylesheet required.

4,674
MIT
Used by 59
94Health
Framework npm

TanStack Router

A fully type-safe React router with built-in data loading, caching, and URL search-param validation.

15,136
MIT
Used by 57
90Health
Tool npm

SWC

Rust-based JavaScript/TypeScript compiler, a drop-in super-fast alternative to Babel

34,208
Apache 2.0
Used by 56
90Health
Library Cargo

Clap

The most widely used command-line argument parser for Rust, with both derive and builder APIs.

16,725
Other
Used by 56
91Health
Library npm

react-dropzone

A lightweight React hook for building HTML5-compliant drag-and-drop file upload zones.

11,012
MIT
Used by 56
49Health
Library npm

prism-react-renderer

A lightweight, themeable Prism syntax highlighter for React and React Native, built on a render-props API.

1,995
MIT
Used by 55
84Health
Library PyPI

cryptography

The standard cryptographic library for Python, pairing safe high-level recipes with low-level primitives backed by Rust and OpenSSL.

7,786
Other
Used by 54
75Health
Library npm

React CodeMirror

A fully-typed React component and hook for embedding the CodeMirror 6 code editor with themes and language extensions.

2,253
MIT
Used by 54
78Health
Library npm

markdown-it

A fast, pluggable CommonMark-compliant Markdown parser and renderer for JavaScript, safe by default.

21,945
MIT
Used by 52
90Health
Library npm

React Email

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

19,788
MIT
Used by 51
82Health
Library npm

Embla Carousel React

A lightweight, dependency-free React hook for building fluid, touch-precise carousels and sliders.

8,429
MIT
Used by 51

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