Following their tutorial (https://instantdb.com/tutorial), I built this open-source QR code generator with authentication in under 15 minutes while sitting in an Uber.

Demo: https://qr-vibes.vercel.app

Source code: https://github.com/zlwaterfield/qr-vibes

What made this special: the app itself isn't groundbreaking even a little bit – it's the build experience that impressed me. This was hands down the simplest auth + database + full app setup I've ever experienced.

What worked incredibly well:

- High-quality documentation (claude.md + instant-rules.md) gave my LLM perfect context

- Schema design is incredibly intuitive

- Authentication is dead simple to implement

- Real-time engine makes auth hooks and db calls lightning fast

Here's an example redirect link for the deployed app: https://qr-vibes.vercel.app/r/8lCThR8u.