Beam — LAN File Transfer

Fast, frictionless file transfer for your local network. Send files, text, and messages between computers on the same WiFi with zero setup.

Features

🚀 Performance

• Parallel SHA-256 hashing (all CPU cores via rayon)
• Auto-compression for 10+ files (zips before send, auto-unzips on receive)
• Live telemetry: speed, ETA, per-file and overall progress

💬 Communication

• Transfer notes — attach messages to any send
• Incoming transfer prompt with sender name, file list, size
• Device groups — send to multiple devices in one click

🎯 Control

• Bandwidth throttling (1–50 MB/s or unlimited)
• Transfer filters: All / Active / Done / Failed with live badges
• Trusted devices — auto-accept from known peers
• Watch folders — auto-send new files to a target device
• Cancelable transfers with partial cleanup

🎨 UI/UX

• Windows 11 Fluent design (Mica blur, Segoe UI Variable, amber accent)
• System tray — minimize to background, receives while hidden
• File explorer with list/grid views, inline rename, keyboard shortcuts
• Session stats: aggregate speed, bytes sent/received

🔄 Reliability

• SHA-256 integrity verification (both ends)
• Conflict handling: rename / overwrite / skip
• Auto-update from GitHub releases
• Transfer history and replay
• Cross-platform: Windows, macOS, Linux

Download

→ Get Beam from Releases

• Windows: .msi installer or portable .exe
• macOS: Universal .dmg (arm64 + x86)
• Linux: .AppImage or .deb

Auto-updates when new versions are available.

Quick Start

1. Install Beam on 2+ machines on the same local network
2. Open Beam — nearby devices appear automatically
3. Drag files onto the send panel or use the file explorer
4. Pick a device (or group) and hit Send
5. Receiver accepts → files land in Downloads/Beam

Usage Guide

Sending Files

Drag & drop: Drag files/folders onto the send panel.
File browser: Click the Explorer tab, browse folders, right-click → Send with Beam.
Watch folder: Settings → Watch Folders → pick a folder and target device. Auto-sends new files.

Transfer Notes

Before sending, click "Add note for recipient" and type a message (max 280 chars). The recipient sees it in the accept prompt.

Device Groups

Create a group: Settings → Device Groups → type a name, select devices, click "Create group".
Send to group: In the send panel, click "+ Add device", select your group. All online members are added.

Bandwidth Control

Settings → Send bandwidth limit: cap upload speed to avoid network congestion.

Trusted Devices

When receiving a transfer, toggle "Always auto-accept from [device]". They'll never prompt again—transfers auto-accept to your default save folder.

System Tray

Close the window → Beam keeps running in the background ready to receive. Left-click the tray icon to toggle the window.

Transfer Management

• Filter transfers: All / Active / Done / Failed tabs with live counts
• View file list: Expand any transfer card to see all files + sizes
• Retry failed sends: Click the Retry button on failed transfers
• Clear completed: Bulk-dismiss done/failed transfers with one click
• Session stats: See aggregate speed (Zap icon) and total bytes sent/received

Building from Source

Requirements:

• Node.js 18+ (LTS recommended)
• Rust 1.70+
• Platform-specific:
  • Windows: Microsoft Visual C++ Build Tools
  • macOS: Xcode Command Line Tools
  • Linux: libwebkit2gtk-4.1-dev, libappindicator3-dev, librsvg2-dev, patchelf

Setup:

git clone https://github.com/SawcyD/Beam.git
cd Beam
npm install

# Development (hot reload)
npm run dev

# Production build
npm run build

# Package installer
npm run tauri build

Installers appear in src-tauri/target/release/bundle/.

Project Structure

src/
  ├── components/              UI components
  │   ├── Explorer/            File browser (list, grid, context menu, sidebar)
  │   ├── DeviceList.tsx       Nearby devices
  │   ├── TransferList.tsx     Transfer filtering + stats
  │   ├── TransferItem.tsx     Per-transfer progress (expandable file list, retry)
  │   ├── SendDropzone.tsx     File staging + device/group picker + note field
  │   ├── IncomingPrompt.tsx   Accept/reject with note display
  │   ├── Settings.tsx         Device name, save dir, theme, bandwidth, groups
  │   └── ui/                  Primitives (button, dialog, progress, etc.)
  ├── store.ts                 Zustand state, device groups, bandwidth limit
  └── types.ts                 Protocol types, DeviceGroup, FsEntry, etc.

src-tauri/src/
  ├── lib.rs                   Setup, tray menu, command handlers, bandwidth/groups
  ├── transfer.rs              Send/receive, hashing, compression, bandwidth throttle
  ├── discovery.rs             mDNS peer discovery
  ├── protocol.rs              Wire format (Control, Offer with note, etc.)
  ├── state.rs                 AppState, Settings (bandwidth_limit, groups)
  ├── explorer.rs              File browser commands
  ├── watch.rs                 Folder monitoring + auto-send
  ├── updater.rs               Update check/install
  └── history.rs               Transfer log

.github/workflows/
  ├── release.yml              Build & sign on git tag, create GitHub release
  └── ci.yml                   Type-check & cargo check on push

How It Works

Discovery:

• mDNS advertises _beam._tcp service with device name + ID + port
• Peers resolved via DNS-SD, shown in Nearby list

Transfer Protocol:

1. Sender → Receiver: TCP connection, sends Offer (files, SHA-256, optional note, compress flag)
2. Receiver → Sender: Response { accept: bool }
3. If accepted: Sender streams file bytes in order, receiver hashes & writes
4. Both emit transfer-progress (speed/ETA) and transfer-done (status)
5. If compressed: receiver unzips archive and cleans up

Bandwidth Throttle:

• Per-chunk sleep: if limit is 10 MB/s, sleeps to stay within that rate

Device Groups:

• Stored in settings.json as { id, name, device_names: ["Device A", "Device B"] }
• Matched by device name (stable for LAN peers)
• When sent to, resolves group names → online devices with those names

Tech Stack

• Frontend: React 18, TypeScript, Tailwind CSS, Zustand, Framer Motion, Lucide icons
• Backend: Tauri 2, Rust, Tokio async
• Protocols: mDNS (mdns-sd), TCP with length-framed JSON (serde), SHA-256 (sha2), ZIP (zip v2)
• Utilities: Rayon (parallel hashing), Trash (safe deletes), Window Vibrancy (Mica), Notify (watch folders)
• CI/CD: GitHub Actions (auto-release on git tag)

Roadmap

• Clipboard sync (live bidirectional sharing)
• Screenshot → send (global hotkey, auto-stage PNG)
• File request (ask peer for a file)
• Transfer queue reordering (drag to prioritize)
• Bidirectional folder sync
• Beam Link (temporary HTTP download URL for non-Beam clients)

Troubleshooting

Devices not appearing?

• Both machines must be on the same local network/subnet
• Check firewall (mDNS port 5353, your listening port)
• Restart Beam on both sides

Transfer stalls or is slow?

• Check network congestion/WiFi signal
• Enable bandwidth throttling in Settings
• Try a smaller file to isolate the issue

Update check fails?

• Repo must be public (auto-update requires no auth)
• Check internet connection
• Manually download from Releases if needed

Contributing

Report issues: GitHub Issues

Submit code:

1. Fork the repo
2. Create a feature branch (git checkout -b feature/my-idea)
3. Test locally
4. Open a pull request

License

MIT License — free to use, modify, distribute.

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Made with ❤️ for frictionless local file transfer.
GitHub · Issues · Releases