local-chat

Private local network CLI chat. No server, no logs, just vibes.

Same WiFi, terminal-based, fully encrypted, completely volatile.

Quick Start

npx local-chat

Enter a nickname and you're in the lobby — a global LAN chatroom where everyone on the same network can talk. From there, create or join private rooms.

Features

• Lobby — Global chatroom for everyone on the network. No setup needed.
• Private rooms — Create encrypted rooms, optionally password-protected.
• Auto discovery — Rooms broadcast via UDP. No IP sharing needed.
• Fully local — No external server. Works on the same WiFi only.
• Volatile — Messages exist in memory only. Leave the room, they're gone.
• Encrypted — AES-256-GCM on all private room messages.
• Boss mode — Instant fake system monitor overlay. Press Tab to hide everything.
• Korean input — Full IME support with proper display width handling.
• Update check — Notifies you on startup if a newer version is available.

Flow

Nickname → Lobby (global chat) → Browse Rooms → Create / Join → Private Chat
                                      ↑                              │
                                      └──────── Esc ×2 ──────────────┘

Commands

| Command | Alias | Description | |---------|-------|-------------| | /help | | Show help overlay | | /users | | List online users | | /erase | /e, /clear | Clear all messages | | /copy [N] | /c | Copy Nth recent message to clipboard | | /fake | /f | Boss mode | | /version | | Show current version | | /quit | | Leave room |

Kaomoji — type to send as a message:

| Command | Output | |---------|--------| | /shrug | ¯\_(ツ)_/¯ | | /tableflip | (╯°□°)╯︵ ┻━┻ | | /unflip | ┼─┼ノ( º _ ºノ) | | /lenny | ( ͡° ͜ʖ ͡°) | | /disapproval | ಠ_ಠ | | /sparkles | (ﾉ◕ヮ◕)ﾉ*:・ﾟ✧ |

Shortcuts

| Key | Action | |-----|--------| | Tab | Boss mode (instant!) | | Shift+↑↓ | Scroll messages | | PgUp / PgDn | Page scroll | | Esc ×2 | Browse rooms | | Ctrl+C | Exit |

Screenshots

Add your own screenshots to assets/ and uncomment the image tags.

Lobby Chat

npx local-chat → enter nickname → lobby. Capture the header, chat messages, and input bar.

Room Browser

Press Esc×2 in lobby → room list with available rooms and Create Room option.

Boss Mode

Press Tab anywhere → instant fake system monitor overlay. Press any key to return.

How It Works

Room Creator (Host)                    Participants
┌─────────────────────┐               ┌──────────────┐
│ WebSocket Server    │◄──────ws─────►│ WS Client    │
│ (message relay)     │               └──────────────┘
│                     │               ┌──────────────┐
│ UDP Broadcaster     │──broadcast───►│ UDP Listener  │
│ (room announce)     │  port 41568   └──────────────┘
└─────────────────────┘

Lobby (all peers)
┌──────────┐  UDP broadcast  ┌──────────┐
│  Peer A  │◄───port 41569──►│  Peer B  │
└──────────┘                 └──────────┘

• Lobby: All users exchange messages via UDP broadcast (port 41569). Obfuscated, not encrypted — meant for casual chat before joining a room.
• Private rooms: The room creator runs a WebSocket server. All messages are encrypted with AES-256-GCM. Password rooms derive keys via PBKDF2; public rooms use a random session key.
• Discovery: Room info is broadcast via UDP every 3 seconds (port 41568). The room browser shows available rooms with 🔒 for password-protected ones.

Security

• Messages encrypted with AES-256-GCM (Node.js built-in crypto)
• Passwords hashed with SHA-256, keys derived with PBKDF2 (100k iterations)
• Nothing written to disk. Ever.
• Network-local only — no internet traffic

Requirements

• Node.js >= 18
• Same WiFi/LAN network

License

MIT