Screener

Screener is a private, low-latency screen-sharing tool for one game player and up to 20 authenticated friends. Web Viewers need no installation. Media is automatic and P2P-first, with bounded Browser relay and one dedicated LiveKit SFU/UDP fallback rather than an always-SFU conference topology.

Project memory is the compact product map. Current status owns the exact source and production state; this README intentionally does not mirror release details.

Screener Client

The Client opens the same interface in your system browser. The Windows package includes its runtime; you do not need to install Node.js separately.

• Local: share with devices on the same LAN.
• Public link: send an ordinary invitation link. Cloudflare Quick Tunnel carries room access and signaling; media travels between peers without an SFU.
• Site: open a saved Screener server and use the running Client for native capture or compatible media forwarding. The Site can provide its SFU fallback.

Choose Browser, application/window, or screen in the source picker. Native screen audio uses the default system output; window audio uses the selected application when supported. Audio has a separate sharing switch. Native capture on Windows offers VP8, Auto, and H264 in the same controls as Browser capture. Other native platform adapters currently use hardware H.264.

P2P is best effort, not a guarantee that every network pair connects. The current status lists platform acceptance and open Client issues. Client access is open by default; its launcher can set an optional site-access password. This does not change access rules on a saved Site.

Local Development

Node.js 24 and npm 11 are required.

npm ci
npm run dev

Open http://localhost:8787. The development server listens on 0.0.0.0, so a phone on the same LAN may use http://<computer-lan-ip>:8787. Screen capture must remain on localhost or HTTPS. Set PUBLIC_BASE_URL and ALLOWED_ORIGINS when generated invitations need a different LAN origin.

Production requires an independent visible-ASCII SITE_ACCESS_PASSWORD; local development and tests may leave it empty. Cross-network setup is documented in self-hosting and configuration reference. Never commit real credentials.

Run complete automated validation with:

npm run check

Documentation

• Product and repository map
• Rooms and access
• Routing and transport
• Capture and media quality
• Presentation and lifecycle
• Current work
• Contributing workflow

License

Screener's own code is MIT licensed. Redistributed components retain their own licenses and notices; see third-party licensing.