DEVxCast

A WebRTC-based screen sharing application that uses Supabase for signaling between casters and presenters.

Prerequisites

• Bun installed on your system

Setup

1. Install dependencies:

   bun install

2. Set up Supabase:

   • Create a new Supabase project at https://supabase.com
   • Get your project URL and anon key from the project settings

3. Configure environment variables: Create a .env.local file (or .env) in the root directory:

   BUN_PUBLIC_SUPABASE_URL=your_supabase_project_url
   BUN_PUBLIC_SUPABASE_ANON_KEY=your_supabase_anon_key
   

   Bun automatically loads .env.local / .env and exposes variables prefixed with BUN_PUBLIC_* to the client. .env.local is typically gitignored, which makes it a safe place for local credentials.

4. Set up database tables:

   • Run bun setup-supabase.ts — the helper script checks tables and prints the SQL you need
   • Copy the SQL (also found in supabase-schema.sql) into the Supabase SQL editor and click Run
   • The script will verify your connection and guide you through the setup

5. Run the development server:

   bun run dev

6. Open the app: The server will display the URL when it starts (typically http://localhost:3000). Open that URL in your browser.

How it works

Caster console

• Capture a real screen share or fall back to a dummy video stream for testing
• Publish a Supabase offer with metadata (name + room code)
• Share a one-click invite link (?role=presenter&room=XXXXXX)
• Auto-subscribes to answers via Supabase Realtime and finalizes the WebRTC connection when the presenter accepts

Presenter console

• Live feed of pending offers, filterable by room code
• Accept/deny buttons write directly to Supabase and create the WebRTC answer
• Active feeds render inline players with fullscreen controls
• Connection health tracked via RTCPeerConnection state

Database Schema

The application uses two tables:

• offers: WebRTC offer SDP + metadata (caster_name, room_code, status)
• answers: WebRTC answer SDP linked to an offer

See supabase-schema.sql for the complete schema definition.

GitHub Pages Deployment

The app automatically deploys to GitHub Pages on push to main. Configure these secrets in Settings → Secrets and variables → Actions:

• BUN_PUBLIC_SUPABASE_URL - Your Supabase project URL (from Settings → API)
• BUN_PUBLIC_SUPABASE_ANON_KEY - Your Supabase anon key (from Settings → API)

Enable GitHub Pages in repository settings and select "GitHub Actions" as the source.