Read the story, then drive the real product.

A demo is usually slideware — or a naked URL.

When you want to show someone a working product, you get two bad choices: a deck that proves nothing, or a raw link with no story, no context, and often no access control. Shipping several demos makes it worse — every one needs its own login, its own subdomain, its own plumbing.

Kart's answer: let people read the story, then try the real thing. Trust comes from a working demo plus honest documentation — never from slideware.

One shelf. Many finished apps. One login per app.

Kart is a public umbrella hub — browse it freely, no gate. Each app on the shelf is a real, deployed product with its own email→PIN door. Access is per app, not per shelf: entering Setu doesn't unlock LensLab. That's why one Kart link is safe to hand to anyone — the shelf is open, but the apps stay yours.

The clever part isn't any single gate — it's that one shared betadoc engine gives every app on the shelf the same email→PIN door with zero per-app auth code. Add an app, point its card at its subdomain, and it inherits the login for free.

Two clean surfaces, one keyless engine behind them.

A visitor only ever sees tidy *.smritiraj.online subdomains. Behind them, a single reverse proxy fans many demos through one tunnel port, and a shared gate mints the PINs.

Two rules keep it safe as it grows: the default, no-prefix tunnel route always points at the incumbent demo, so adding an app can never break an existing one — and multiplexing is done by path prefix, never host header, because static-host proxies rewrite forwarded-host headers.

What's actually built — honestly.

A matrix that shows everything green is a matrix nobody believes. Here's what's live, what's partial, and what's still on the roadmap.

What's next on the shelf.

• 1

  Verify send.smritiraj.online in Resend

  Flip every app from on-screen PINs to real emailed PINs from an @smritiraj.online address — one env var, no code change.

• 2

  Record the narrated walkthrough

  Headless-browser capture of real in-app motion, voiceover, ffmpeg assembly — embedded in the hero where the still frame sits today.

• 3

  Finish LensLab's reverse-proxy ownership

  Run takeover.sh so LensLab serves from its own clean subdomain instead of the raw Vercel URL.

• 4

  Grow the shelf

  Every new demo inherits the shared gate and the path-prefix multiplex — adding one is a card plus a proxy block.

Two surfaces, deployed the boring, reliable way.

Each surface is its own explicitly-named Vercel project on a clean subdomain — never auto-named, never left behind default SSO. Adding a demo is additive by construction.

Secrets live in gitignored env files, never in the repo. The engine holds the sending key, so the apps themselves stay keyless. Demo data is synthetic — no real customer data on a public demo.