LocalBolt

localbolt.app - use it now, no install needed.

Encrypted peer-to-peer file transfer. Files go directly between devices, never stored on any server.

• End-to-end encrypted with NaCl/Curve25519 (same crypto as Signal and WireGuard)
• Direct transfer - files never touch a server
• No accounts - no sign-up, no cloud, no trace
• No file size limits - limited only by your device storage
• Cross-platform - works in any modern browser
• LAN discovery - discovers nearby devices on your local network
• Works offline - self-host on your local network with no internet required

Quick Start

git clone https://github.com/the9ines/localbolt.git
cd localbolt
./start.sh

That's it. The script installs any missing dependencies (Rust, Node.js), builds the signaling server, and starts everything.

Open http://localhost:8080 on two devices. Devices discover each other automatically. Select one and start transferring.

Windows:

start.bat

If Rust or Node.js aren't installed, the script will tell you where to get them.

How It Works

1. Open LocalBolt on two devices on the same local network
2. Select the other device from the device list (it appears automatically)
3. Transfer files by drag-and-drop, encrypted, peer-to-peer, no size limits

The signaling server only helps devices find each other. Once connected, all data flows directly between devices over an encrypted WebRTC channel. The signaling server never sees your files.

Local Discovery

LocalBolt is LAN-only. Its signaling server helps nearby devices on your local network find each other. It does not provide cross-internet discovery or remote-network transfer.

• Same network: Devices on your LAN discover each other automatically
• Offline mode: If there's no internet, LAN discovery still works

Architecture

┌─────────┐     WebSocket      ┌──────────────────┐     WebSocket      ┌─────────┐
│ Device A │◄──────────────────►│  Signal Server   │◄──────────────────►│ Device B │
│ (browser)│   (discovery +     │  (Rust, port     │   (discovery +     │ (browser)│
│          │    connection       │   3001)          │    connection      │          │
│          │    setup only)      └──────────────────┘    setup only)     │          │
│          │                                                            │          │
│          │◄══════════════════════════════════════════════════════════►│          │
│          │              WebRTC Data Channel (direct)                  │          │
│          │           NaCl encrypted file transfer                     │          │
└─────────┘                                                            └─────────┘

Manual Setup

If you prefer to run the components separately:

Signaling server:

cd signal
cargo run --release

Web app:

cd web
npm install
npm run dev

Tech Stack

Component	Technology
Web UI	Vanilla TypeScript, Tailwind CSS
Encryption	TweetNaCl (NaCl box: Curve25519 + XSalsa20-Poly1305)
Transfer	WebRTC data channels, 16KB chunks
Signaling	Rust (Tokio + Tungstenite WebSocket)
Discovery	LAN/local-network signaling, IP-based peer grouping

Ecosystem

LocalBolt is part of the Bolt Protocol ecosystem. See PRD.md and ROADMAP.md in this repo for product requirements and roadmap.

Relationship	Repository
Ecosystem governance (mirror)	bolt-ecosystem
Protocol spec	bolt-protocol
SDK dependency	bolt-core-sdk
Bundles (subtree)	bolt-rendezvous
Native/mobile app shells	localbolt-app
Production web app	localbolt-v3

This is an open-source project. Free to use, self-host, and modify.

Related

• localbolt.app — use it in the browser, no install
• LocalBolt App — native/mobile shells over the shared Rust core

License

MIT — built by the9ines