Open Source Packages
Libraries, frameworks, tools, and SDKs used by the apps in this directory — scored the same way as the apps themselves.
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AI SDK
Provider-agnostic TypeScript toolkit for building AI apps and agents with any LLM.
Pydantic
Data validation and settings management using Python type hints, backed by a Rust core.
pytest
The Python testing framework that makes writing small tests easy and scales to complex functional test suites.
react-i18next
React bindings for the i18next internationalization ecosystem, built on hooks and a translation-aware Trans component.
next-themes
Perfect dark mode for React and Next.js apps in two lines of code, with zero flash on load.
react-day-picker
A lightweight, fully customizable date picker component for React applications.
HTTPX
A next-generation HTTP client for Python with sync, async, and HTTP/2 support
Storybook
The industry-standard workshop for building, documenting, and testing UI components in isolation, across every major frontend framework.
Tiptap Core
Headless, framework-agnostic rich text editor toolkit built on ProseMirror
TanStack Virtual (React)
Headless React hook for virtualizing massive lists, grids, and tables at 60FPS.
Uvicorn
A lightning-fast ASGI server for Python, built on uvloop and httptools.
NumPy
The fundamental N-dimensional array library powering Python's scientific computing stack.
React Resizable Panels
Resizable, draggable panel group layouts for React with keyboard accessibility and SSR support built in
PyYAML
A full-featured YAML parser and emitter for Python, with C-accelerated bindings
React Flow
A highly customizable React library for building node-based editors, diagrams, and interactive flow charts.
FastAPI
A modern, high-performance Python web framework for building APIs with automatic validation, serialization, and interactive docs.
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
@monaco-editor/react
Drop the Monaco code editor into any React app without touching webpack, rollup, or bundler config files.
undici
A fast, spec-compliant HTTP/1.1 client for Node.js, built from scratch with zero runtime dependencies
Floating UI
React hooks and components for building accessible, perfectly positioned tooltips, popovers, and dropdowns.
MDX
The compiler that lets you write JSX directly inside Markdown documents
classnames
A tiny utility for conditionally joining CSS class names together.
Emotion
Performant, flexible CSS-in-JS styling for React with the css prop, theming, and SSR support
eslint-plugin-jsx-a11y
Static ESLint rules that catch JSX accessibility issues before code ships.
