🦙 Japanese Slack Translator

A beautiful, lightweight desktop app that translates selected text between Japanese and English using Cloudflare Workers AI with Gemma 3. Works anywhere on your Mac with a global hotkey (Cmd+J).

Cloud-Powered: Powered by Cloudflare Workers AI for accurate translations. Requires internet connection.

Features

✨ Global Hotkey Translation

• Press Cmd+J anywhere on your Mac to translate selected text
• Works in any app (Slack, Gmail, browsers, etc.)

🎯 Smart Language Detection

• Automatically detects if text is Japanese or English
• Translates to the opposite language

☁️ Cloud-Powered

• Uses Cloudflare Workers AI with Gemma 3 model (140+ languages)
• Requires internet connection
• Powered by global edge network for low latency
• Your translations are processed by Cloudflare (see their privacy policy)

🎨 Beautiful UI

• Cute floating overlay with llama mascot 🦙
• Auto-hides after 10 seconds
• Copy translation with one click
• Smooth animations

⚡ Zero Setup

• Cloud-based, nothing to install except the app
• Works immediately after download
• Automatic configuration from Cloudflare Worker URL

Installation

Prerequisites

• macOS (M1/M2/M3 or Intel)
• Node.js 16+ (for development)
• Rust 1.70+ (for building)
• Internet connection (for translations)

1. Deploy Cloudflare Worker

First, set up the translation backend by deploying a Cloudflare Worker:

1. Go to https://dash.cloudflare.com
2. Navigate to Workers & Pages → Create application → Create Worker
3. Name it: translator-proxy
4. Copy the Worker code from the plan documentation
5. Paste into the Worker editor and deploy
6. Copy your Worker URL: https://translator-proxy.<your-account>.workers.dev

2. Setup This App

# Clone the repo
git clone https://github.com/yourusername/japanese-slack-translator.git
cd japanese-slack-translator

# Install dependencies
npm install

# Install Cargo
curl https://sh.rustup.rs -sSf | sh


# Start development (hot reload)
npm run tauri dev

# Or build for production
npm run tauri build

The built app will be in src-tauri/target/release/bundle/.

Usage

Basic Translation

1. Select any text (Japanese or English)
2. Press Cmd+J (Ctrl+J on Windows)
3. Translation appears in the overlay
4. Click "Copy" or wait 10 seconds to auto-hide

Grant Permissions

On first run, macOS may ask for Accessibility permissions:

• Go to System Settings → Privacy & Security → Accessibility
• Add your Terminal app to the list
• Restart the app

Configuration

Create a .env file in the project root with your Cloudflare Worker URL:

# Your Cloudflare Worker URL (from step 1)
WORKER_URL=https://translator-proxy.<your-account>.workers.dev

Replace <your-account> with your Cloudflare account subdomain.

Architecture

Frontend (React + TypeScript)

• src/App.tsx - Main app container
• src/components/TranslationOverlay.tsx - Translation result display

Backend (Rust + Tauri)

• src-tauri/src/lib.rs - Application setup & hotkey registration
• src-tauri/src/commands.rs - Tauri commands (translation)
• src-tauri/src/translation.rs - Cloudflare Worker integration
• src-tauri/src/config.rs - Configuration management
• src-tauri/src/clipboard_manager.rs - Smart clipboard handling

How It Works

1. Hotkey Detection: Global hotkey listener catches Cmd+J
2. Clipboard Capture: Simulates Cmd+C to copy selected text
3. Language Detection: Analyzes character ranges (Hiragana, Katakana, Kanji)
4. Translation: Sends text to Cloudflare Worker proxy for translation
5. Display: Shows result in overlay, user can copy
6. Cleanup: Restores original clipboard content

Development

Prerequisites

npm install      # Install Node dependencies
cargo check      # Verify Rust setup

Run in Development Mode

npm run tauri dev

This opens the app with hot reload for frontend changes.

Type Checking

npm run build    # TypeScript check
cargo check      # Rust check

Build for Production

npm run tauri build

Output: src-tauri/target/release/bundle/

Performance

All MacBooks:

• Translation latency: 1-2 seconds (network + cloud processing)
• Powered by Cloudflare's global edge network for low latency
• Memory: Minimal (cloud processing)
• CPU: Minimal (only clipboard + UI operations)

Requirements:

• Stable internet connection (required for translations)
• Cloudflare Worker endpoint must be reachable

Troubleshooting

"Cannot reach translation service"

• Check your internet connection
• Verify your Cloudflare Worker is deployed and running
• Check your WORKER_URL in .env is correct

Hotkey doesn't work

Go to System Settings → Privacy & Security → Accessibility and add your Terminal app.

Slow translations

• Check your internet connection speed
• Cloudflare Workers have global edge deployment, so latency is usually <1s
• If translations are slow, it may be a network issue on your end

Translations are poor quality

• Gemma 3 is a high-quality model (12B parameters)
• If translations seem off, try rephrasing your input
• The model is multilingual and optimized for 140+ languages including Japanese

Contributing

Contributions welcome! Please:

1. Fork the repo
2. Create a feature branch (git checkout -b feature/amazing-thing)
3. Commit your changes (git commit -m 'Add amazing thing')
4. Push to the branch (git push origin feature/amazing-thing)
5. Open a Pull Request

Areas for Contribution

• Additional language support
• Performance optimizations
• Better error messages
• UI improvements
• Translation quality tweaks
• Windows/Linux support

License

MIT License - see LICENSE file for details

TL;DR: Use it however you want, commercially or personally, just include the license notice.

Acknowledgments

• Cloudflare Workers AI - Cloud-based AI translation
• Google Gemma 3 - Language model
• Tauri - Desktop app framework
• React - UI library

Privacy & Security

✅ No telemetry ✅ Cloud-based processing (via Cloudflare) ✅ No credentials in desktop app (API token stays server-side) ✅ Rate limiting (100 requests/hour per IP) ✅ Open source (inspect the code)

⚠️ Privacy Note: Your translations are processed by Cloudflare. See Cloudflare's privacy policy for details.

Roadmap

• Windows support
• Linux support
• Additional language pairs (Spanish, French, etc.)
• Translation history
• Custom translation styles (formal, casual, etc.)
• Voice input/output
• Batch file translation

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Made with ❤️ for translating between Japanese and English.