zk-Waldo

zk-Waldo turns the classic Where's Waldo puzzle into a real zero-knowledge demo. A prover clicks Waldo in one of six real puzzle pages, builds a private witness in the browser, and generates a RISC Zero receipt that proves the selected crop passes an agreed trained CNN.

The verifier only sees the public image root, model hash, threshold, and receipt. The location, crop pixels, Merkle path, and tile index remain private, making the demo a playful way to understand private inference, image commitments, and verifiable computation working together.

What makes it real:

• Six real puzzle pages with separate tiled SHA-256 Merkle commitments
• A trained and quantized CNN for Waldo detection
• RISC Zero receipts for end-to-end proof generation and verification
• A split-screen prover and verifier flow designed for demos