gather — the conversation studio

A browser studio for up to six people: live video over WebRTC, a composited 16:9 stage, host-controlled layouts, banners, a scrolling ticker, branding, studio chat and one-click recording.

What's inside

• Scenes: one-click scene strip (number keys 1–9) with presets for interviews, panels, presentations, AI research and chat. Build your own on the stage by dragging and resizing elements, and save them as scenes.
• Presenting: share a screen (with its sound), play a video file, or present PDF slides with ← / →. Cameras stay live on a second track, and the stage switches to a presentation scene by itself.
• On-air AI: research live with your own Claude, ChatGPT, Gemini or Grok API key, and put the answer on screen as it streams. Claude and Gemini can search the web.
• Platform chat: Twitch and Rumble chat in studio chat and in the on-stage overlay, with host moderation (hide, time out, block).
• Support links: PayPal, Venmo, Cash App, Stripe, Ko-fi, Patreon and Buy Me a Coffee as scannable QR cards on stage.
• Accounts: email + password (scrypt), nickname and photo, password change and reset, and settings that follow you between devices.
• Start a stream: go live now or schedule up to 29 days ahead, with emailed invites, a calendar file, and reminders a day and 15 minutes before. Scheduled studios keep the host seat for their owner.
• Thumbnails: design one from your camera and headline, generate an AI background with your own ChatGPT, Gemini or Grok key, or upload your own.
• Camera and mic: AI noise removal (RNNoise), echo cancellation, gain, light correction, background blur or replacement (MediaPipe), and a chroma-key green screen.
• Live captions in 14 languages, vertical 9:16 scenes for TikTok, Reels and Shorts, a guest view without host controls, and searchable help that jumps to the exact setting.
• Profile photos for guests whose camera is off, banners, a ticker, brand colours and stage backgrounds, and recording to a local video file.

Deploy to Vercel

1. Import this repository in Vercel (Add New → Project). No build settings are needed; vercel.json serves public/ and the api/ function.
2. In the project, open Storage, create a Redis database (Upstash, free plan is fine) and connect it to the project. Any of these variables works, whichever Vercel adds: KV_REST_API_URL + KV_REST_API_TOKEN, UPSTASH_REDIS_REST_URL + UPSTASH_REDIS_REST_TOKEN, or REDIS_URL.
3. Redeploy (Deployments → ⋯ → Redeploy) so the function picks up the new variables.
4. Check it: open https://<your-app>.vercel.app/api/studio?action=config. You want "ok": true. If not, problem says what's wrong and envDetected lists which variable names the function can see.

Open the deployment URL, create a studio, and send the invite link to a second device. Any setup problem also appears in red in the "Step into the studio" dialog.

Email (invites, reminders, password reset)

gather sends email through Resend and schedules reminders with Resend's scheduled_at, so no cron job is needed.

Variable	Example	Notes
RESEND_API_KEY	re_…	From resend.com → API Keys
MAIL_FROM	gather <[email protected]>	Must use a domain verified in Resend
APP_URL	https://gather-gold-nine.vercel.app	Used in email links; defaults to the request's host

Without these, accounts, scheduling and everything else still work; the app says plainly that emails were not sent.

Optional environment variables, for guests on strict corporate or mobile networks:

Variable	Example
TURN_URL	turn:turn.example.com:3478 (comma-separate several)
TURN_USER	short-lived username
TURN_PASS	short-lived credential

Guests can also enter their own TURN details under Settings (kept for that browser session only).

Run locally

npm start            # http://localhost:8080 — no install needed, no database needed

Open two tabs, create a studio in one, and join with the code or invite link in the other. Locally the studio state lives in memory. Set KV_REST_API_URL and KV_REST_API_TOKEN to use Redis instead. Camera and screen capture need HTTPS or localhost.

How it works

• Signaling over HTTP. Vercel functions can't hold WebSockets open, so lib/studio.js is a stateless handler over Redis. Each participant has a private inbox list. The browser polls it every 300 ms while connections are being set up and about once a second after that, and every 2.5 s when the tab is hidden. Outgoing messages (ICE candidates, chat, stage changes) are batched into single requests. server.js runs the same handler for local use.
• Presence. Every fourth second a poll doubles as a heartbeat. Anyone silent for 20 s is removed, and hosting passes to the longest-standing guest. Closing the tab sends a leave beacon right away. If a laptop sleeps and its seat expires, the page rejoins the studio by itself.
• Media is peer-to-peer. Full mesh: the newest participant offers to everyone already present, so offers never collide. Mic, camera, device and screen-share changes use replaceTrack, so there is no renegotiation. A failed connection triggers an ICE restart.
• The stage is a <canvas> drawn every frame from everyone's video. That same canvas plus a Web Audio mix of all participants feeds MediaRecorder, so a recording matches the stage exactly.

Redis usage

An idle participant costs about one Redis command per second. A one-hour session with six people uses roughly 25–30k commands. Studios expire after six hours without activity.

On-air AI keys

Each host pastes their own provider key in the AI panel. It is kept in that browser's local storage and sent with each question through /api/ai to the provider; gather never stores or logs it. Claude requests use the official Anthropic SDK with web search and server-side refusal fallback.

Third-party code

pdf.js and qrcode-generator are served from public/vendor/ (licences in public/vendor/LICENSES.md).

Shortcuts: M mute · V camera · S share screen · ← → slides · 1–9 scenes · R record · F full screen · / chat.