Collabydraw

🎨 Hand-drawn look & feel • Collaborative • Secure

CollabyDraw is a web-based collaborative whiteboard where multiple users can draw, edit, and brainstorm together in real time. Whether solo or in a group session, the app offers a smooth, intuitive canvas experience with real-time sync, shape tools, editable text, and privacy-focused end-to-end encryption — all without needing an account.

Github Repo

https://github.com/coderomm/CollabyDraw

✅ Core Features

Canvas Drawing: Freehand, shapes, and editable text
Rough.js Support: Optional sketch-style drawing
Perfect-freehand Support: Hand drawn feel
Eraser Tool: Remove individual shapes
Editable Text: Double-click to edit on canvas

🔗 Collaboration

Real-time Sync: WebSocket-powered live drawing
Multi-Tab Awareness: No duplicate join/leave events
Optimistic Updates: Instant feedback before server response

🔐 Privacy & End-to-End Encryption (E2EE) in CollabyDraw

CollabyDraw is built with privacy by design to ensure that no sensitive drawing data can be accessed by anyone other than the intended participants.

🔑 How It Works

When a user creates or joins a room, the app generates a link like:
<https://collabydraw.app/#room=abc123,xyz456>
- abc123: Unique room ID (used by the server)
- xyz456: Encryption key (used only on the client)

🧠 Key Never Touches the Server

The encryption key after the comma (xyz456) is part of the URL fragment (#...).
This fragment is never sent in HTTP requests, meaning:
The server cannot see or store the encryption key.

🔒 Client-Side Only Decryption

All encrypted drawing data is transmitted over WebSocket.
The decryption and rendering happen completely on the client-side using the key from the URL.
Even if someone intercepts the WebSocket traffic, they cannot decrypt the data without the key.

🛡️ Benefits

No one — not even the server — can read what’s drawn in a room without the key.
Ensures confidentiality for private brainstorming, teaching, or design sessions.
Works like Excalidraw's E2EE rooms, but tailored for your collaborative drawing logic.