💬 SyncLan

An Instant-Messaging-Style LAN File Transfer Tool

Bringing a "Lark/Feishu-grade IM experience" to local network file sharing. Anytime, anywhere, ready out of the box.

English | 简体中文

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SyncLan is an instant-messaging-style file transfer tool built for local area networks (LANs). It breaks away from the cold, drag-and-drop workflow of traditional transfer tools by seamlessly integrating chat and file sharing into a single unified interface. Once devices on the same Wi-Fi or LAN are automatically discovered, you can exchange plain text, rich text, images, and files just as you would in a modern IM app.

The desktop client acts as a "communication hub" running locally, allowing other LAN devices (smartphones, tablets, or other PCs) to connect instantly via any web browser without installing any apps.

💡 Ideal For: Cross-device office collaboration, dorm/home network sharing, environments without public internet access, or any scenario where you want to avoid third-party cloud drives and chat apps for temporary file transfers.

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✨ Features

• 💬 Lark-grade IM Experience: Closely models the conversation list and chat layout of Lark/Feishu, featuring meticulous visual interaction details for zero learning curve.
• 🖼️ Pixel-Perfect Rich Text Editor: Supports formatted text editing, inline live previews for images and attachments, and infinite scroll for message history, giving it the smooth feel of a mature IM application.
• 📁 High-Speed LAN Transfers: Direct file transfers saved straight to your designated local folder, leveraging full local network bandwidth without public speed caps.
• 🖥️ Desktop Host + Zero-Install Web Client: Built on Tauri 2 as a lightweight, cross-platform desktop app with a built-in web server. Mobile phones and other PCs can join instantly by scanning a QR code or entering the IP address in a browser.
• 🔎 Automatic Device Discovery: Uses LAN broadcasts to discover online devices automatically and start messaging with a single click.
• 🔐 HTTPS Support: Built-in self-signed certificate export functionality, enabling full HTTPS encryption once trusted.
• ⚙️ Highly Customizable: Supports multi-language switching (English/Chinese), light/dark themes, auto-start on boot, silent tray launch, auto-cleanup of expired files, and more.
• 🧩 Open API Documentation: Includes built-in Swagger UI (/api/docs) for easy secondary development and automated integrations.

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📸 Screenshots

Desktop Interface

Welcome screens, rich-text image messages, and file transfers in light and dark modes.

Mobile Browser View

Welcome screens and conversations in a mobile browser, with light and dark mode support.

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🎨 Design & UI System

SyncLan's frontend UI is primarily built with shadcn/ui, following modern Web design standards.

🤝 Contributions Welcome: We are constantly refining the UI/UX details. If you have design suggestions, interaction improvements, or Figma/Sketch files to share, feel free to submit an issue or open a pull request!

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🏗️ Architecture & How It Works

SyncLan uses a "Desktop Hub with Zero-Install Mobile/Web Access" design philosophy:

[ Desktop Client (Tauri) ] ---- Port Listener (Default 53317) ---- Socket.IO / Web Server
       |                                                                |
       +---> Device Discovery (Finds other SyncLan desktop clients)      |
       |                                                                |
       +---> Other LAN Devices (Phones / Tablets / PCs) ----> [ Web Browser IP:53317 ]

1. Desktop Host as Communication Hub: Launching the desktop app automatically starts the backend IM service (Axum + Socket.IO) alongside a static web server.
2. Zero-Install Multi-Device Access: Other devices on the same network don't need any app installed. Simply open a browser, navigate to the desktop host's local IP and port, and begin chatting or transferring files right away.
3. Note on Native Mobile Apps: Real-time LAN communication requires persistent long-lived connections (Socket.IO), which drains battery and suffers from strict background termination on iOS and Android. As a result, we currently have no plans for native mobile apps; please use mobile browsers for instant access.

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🚀 Quick Start

1. Download & Install

Head to GitHub Releases and download the appropriate installer for your platform (macOS / Windows / Linux).

2. Default Service Endpoints

Once started, the application listens on port 53317 by default:

• Local Web App: http://127.0.0.1:53317 (Access from local PC browser)
• LAN Web App: http://<LAN-IP>:53317 (Access from phone or other devices)
• API Documentation: http://127.0.0.1:53317/api/docs (Swagger UI for developers)
• WebSocket Node: ws://127.0.0.1:53317/socket (Socket.IO real-time communication endpoint)

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🛠️ Local Development Setup

If you wish to contribute or build SyncLan from source:

Prerequisites

• Node.js: LTS version (v18+ recommended)
• pnpm: Package manager
• Rust: Latest Stable release (includes rust-toolchain.toml)
• Tauri 2 Dependencies: Follow the official Tauri Prerequisites Guide for your OS.

Steps

1. Clone the repository and install dependencies:

   git clone https://github.com/1111mp/synclan.git
   cd synclan
   pnpm install

2. Run the desktop app in development mode:

   pnpm dev

3. Build for production:

   pnpm build

   (Output binaries will be placed under target/release/bundle/)

Useful Development Commands

Command	Description
pnpm dev	Start the Tauri development environment.
pnpm build	Build desktop installers.
pnpm app:dev	Build the web application and preview the desktop UI.
pnpm app:build	Build both the web application and desktop UI.
pnpm web:dev	Start the browser development server.
pnpm web:build	Build browser assets.
pnpm ui:dev	Start the desktop UI development server.
pnpm ui:build	Type-check and build the desktop UI.
pnpm typecheck	Run TypeScript type checking.
pnpm oxlint	Run frontend linting.
pnpm format:check	Check frontend formatting.
pnpm test	Run Vitest tests.
cargo test -p synclan	Run Rust tests.
cargo fmt --all -- --check	Check Rust formatting.
cargo clippy -p synclan --all-targets -- -D warnings	Run Rust Clippy.

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📂 Project Structure

.
├── src/                  # React frontend source (Desktop UI & Web client)
│   ├── components/       # Base UI components, message items, device list, etc.
│   ├── pages/            # View pages (Chat, Discovery, Settings, etc.)
│   ├── lib/              # API wrappers, utility functions, type definitions
│   └── locales/          # i18n internationalization setup
├── src-tauri/            # Tauri / Rust backend source
│   ├── src/server/       # Axum HTTP API, Socket.IO handlers, background workers
│   ├── src/config/       # App configurations & credentials management
│   ├── src/core/         # System tray, logging, window controls, auto-start
│   └── resources/        # Static assets, DB migration scripts
├── scripts/              # CI/CD and build scripts
├── package.json          # Node dependencies and scripts
└── Cargo.toml            # Rust workspace configuration

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❓ Troubleshooting

1. Devices missing from the auto-discovery list?

• Ensure all devices are connected to the exact same Wi-Fi / LAN subnet.
• Check and temporarily disable VPNs, global proxies, or router AP Isolation (Guest Network Isolation).
• Check Windows Firewall or macOS Network Privacy settings to ensure SyncLan is allowed to listen on the configured port.

2. Mobile or remote browser cannot open the web page?

• Verify you are entering the host computer's LAN IP (e.g., 192.168.1.X), not 127.0.0.1.
• Ensure the desktop client is running and the port isn't blocked by local firewalls or occupied by another app.

3. HTTPS shows "Untrusted Certificate" warning?

• SyncLan uses locally generated self-signed certificates. In the desktop settings, click "Export Certificate" and install/trust it in your browser or operating system's Trusted Root Certification Authorities store.

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📄 License

This project is licensed under the MIT License.