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+# Excalidraw
+
+<div align="center">
+  <p>
+    <strong>Virtual whiteboard for sketching hand-drawn like diagrams.</strong><br/>
+    Collaborative and end-to-end encrypted.
+  </p>
+</div>
+
+[![License: MIT](https://img.shields.io/badge/license-MIT-blue.svg)](LICENSE)
+[![npm](https://img.shields.io/npm/dm/@excalidraw/excalidraw)](https://www.npmjs.com/package/@excalidraw/excalidraw)
+[![PRs welcome](https://img.shields.io/badge/PRs-welcome-brightgreen.svg)](https://docs.excalidraw.com/docs/introduction/contributing)
+[![Discord](https://img.shields.io/discord/723672430744174682?color=5865F2&label=discord)](https://discord.gg/UexuTaE)
+
+## Features
+
+- 💯 Free & open-source
+- 🎨 Infinite, canvas-based whiteboard
+- ✍️ Hand-drawn style rendering
+- 🌓 Dark mode
+- 🏗️ Highly customizable
+- 📷 Image support
+- 😀 Shape libraries
+- 🌐 Localization (i18n)
+- 🖼️ Export to PNG, SVG & clipboard
+- 💾 Open format (.excalidraw JSON)
+- ⚒️ Tools: rectangle, circle, diamond, arrow, line, free-draw, eraser, text
+- ➡️ Arrow-binding & labeled arrows
+- 🔙 Undo/Redo
+- 🔍 Zoom and panning
+
+### [excalidraw.com](https://excalidraw.com) extras
+
+- 📡 PWA support (offline)
+- 🤼 Real-time collaboration
+- 🔒 End-to-end encryption
+- 💾 Local-first (browser autosave)
+- 🔗 Shareable links
+
+## Project Structure
+
+```
+packages/
+├── excalidraw/     # @excalidraw/excalidraw - Main React component (npm package)
+├── common/         # @excalidraw/common - Shared utilities and constants
+├── element/        # @excalidraw/element - Element manipulation logic
+├── math/           # @excalidraw/math - Math utilities and types
+└── utils/          # @excalidraw/utils - Export utilities
+
+excalidraw-app/     # Production app (excalidraw.com)
+examples/
+├── with-nextjs/    # Next.js integration example
+└── with-script-in-browser/  # Browser script example
+dev-docs/           # Documentation site (Docusaurus)
+scripts/            # Build and release scripts
+```
+
+## Quick Start
+
+### Using the npm Package
+
+```bash
+npm install react react-dom @excalidraw/excalidraw
+# or
+yarn add react react-dom @excalidraw/excalidraw
+```
+
+```tsx
+import { Excalidraw } from "@excalidraw/excalidraw";
+
+function App() {
+  return (
+    <div style={{ height: "500px" }}>
+      <Excalidraw />
+    </div>
+  );
+}
+```
+
+See the [installation docs](https://docs.excalidraw.com/docs/@excalidraw/excalidraw/installation) for more details.
+
+## Development
+
+### Prerequisites
+
+- [Node.js](https://nodejs.org/)
+- [Yarn](https://yarnpkg.com/) (v1 or v2.4.2+)
+- [Git](https://git-scm.com/)
+
+### Setup
+
+```bash
+git clone https://github.com/excalidraw/excalidraw.git
+cd excalidraw
+yarn
+yarn start
+```
+
+Open [http://localhost:3000](http://localhost:3000) to start developing.
+
+### Commands
+
+| Command | Description |
+|---------|-------------|
+| `yarn start` | Start development server |
+| `yarn test:typecheck` | TypeScript type checking |
+| `yarn test:update` | Run all tests (with snapshot updates) |
+| `yarn fix` | Auto-fix formatting and linting |
+| `yarn start:example` | Start example app on port 3001 |
+
+### Architecture
+
+- **Yarn workspaces** for monorepo management
+- **Vite** for app bundling, **esbuild** for packages
+- **Jotai** for state management
+- **Vitest** for testing
+- **TypeScript** with strict configuration
+
+### Package Development
+
+Work in `packages/*` for editor features, `excalidraw-app/` for app-specific features.
+
+## Dependencies
+
+### Core
+
+| Package | Purpose |
+|---------|---------|
+| `react` | UI framework |
+| `jotai` | State management |
+| `roughjs` | Hand-drawn rendering |
+| `perfect-freehand` | Freehand drawing |
+| `nanoid` | ID generation |
+| `pako` | Compression |
+
+### Build & Dev
+
+| Package | Purpose |
+|---------|---------|
+| `vite` | App bundler |
+| `esbuild` | Package bundler |
+| `typescript` | Type checking |
+| `vitest` | Testing |
+| `eslint`, `prettier` | Code quality |
+
+## Contributing
+
+1. Fork and clone the repo
+2. Run `yarn` to install dependencies
+3. Create a branch: `git checkout -b your-branch-name`
+4. Make changes and run `yarn test:update`
+5. Submit a PR with semantic prefix: `feat:`, `fix:`, `docs:`, `refactor:`, etc.
+
+See the [contribution guide](https://docs.excalidraw.com/docs/introduction/contributing) for details.
+
+## Documentation
+
+- [Full Documentation](https://docs.excalidraw.com)
+- [API Reference](https://docs.excalidraw.com/docs/@excalidraw/excalidraw/api)
+- [Integration Guide](https://docs.excalidraw.com/docs/@excalidraw/excalidraw/integration)
+
+## Integrations
+
+- [VSCode Extension](https://marketplace.visualstudio.com/items?itemName=pomdtr.excalidraw-editor)
+- [npm Package](https://www.npmjs.com/package/@excalidraw/excalidraw)
+
+## Who's Using Excalidraw
+
+Google Cloud • Meta • CodeSandbox • Obsidian • Replit • Slite • Notion • HackerRank
+
+## Support
+
+- [Report Issues](https://github.com/excalidraw/excalidraw/issues)
+- [Discord](https://discord.gg/UexuTaE)
+- [Open Collective](https://opencollective.com/excalidraw)
+
+## License
+
+[MIT](LICENSE)