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

95Health
SDK npm

OpenAI

The official Node.js/TypeScript client for the OpenAI API, auto-generated from OpenAI's own OpenAPI spec.

11,192
Apache 2.0
Used by 86
64Health
Library npm

fs-extra

Drop-in replacement for Node's fs module adding copy, remove, mkdirs, and JSON helpers with native promise support.

9,590
MIT
Used by 84
91Health
Tool PyPI

Uvicorn

A lightning-fast ASGI server for Python, built on uvloop and httptools.

10,993
BSD 3
Used by 83
90Health
Library npm

TanStack Virtual (React)

Headless React hook for virtualizing massive lists, grids, and tables at 60FPS.

7,123
MIT
Used by 83
91Health
Library npm

Tiptap Core

Headless, framework-agnostic rich text editor toolkit built on ProseMirror

38,558
MIT
Used by 82
95Health
Library PyPI

NumPy

The fundamental N-dimensional array library powering Python's scientific computing stack.

32,864
BSD 3
Used by 82
92Health
Library npm

ioredis

A robust, full-featured Redis client for Node.js with built-in Cluster, Sentinel, and TypeScript support.

15,343
MIT
Used by 81
84Health
Library npm

React Resizable Panels

Resizable, draggable panel group layouts for React with keyboard accessibility and SSR support built in

5,377
MIT
Used by 81
53Health
Library PyPI

PyYAML

A full-featured YAML parser and emitter for Python, with C-accelerated bindings

2,950
MIT
Used by 80
50Health
Library npm

cors

Node.js CORS middleware for Express and Connect that sets standards-compliant headers to control cross-origin browser access.

6,195
MIT
Used by 79
91Health
Framework PyPI

FastAPI

A modern, high-performance Python web framework for building APIs with automatic validation, serialization, and interactive docs.

102,676
MIT
Used by 78
91Health
Library npm

React Flow

A highly customizable React library for building node-based editors, diagrams, and interactive flow charts.

38,512
MIT
Used by 78
63Health
Library PyPI

python-dotenv

Load environment variables from a .env file into Python's os.environ, the standard way to keep 12-factor config out of your code

8,883
BSD 3
Used by 73
53Health
Library npm

@monaco-editor/react

Drop the Monaco code editor into any React app without touching webpack, rollup, or bundler config files.

4,746
MIT
Used by 72
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
92Health
Library npm

undici

A fast, spec-compliant HTTP/1.1 client for Node.js, built from scratch with zero runtime dependencies

7,705
MIT
Used by 70
97Health
Framework npm

Electron

Build cross-platform desktop apps with JavaScript, HTML, and CSS on Chromium and Node.js

123,289
MIT
Used by 69
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
85Health
Library npm

Pino

A super fast, low-overhead JSON logger for Node.js applications.

18,227
MIT
Used by 67
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

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