zkVisa

The problem it solves

Traditional immigration and visa management systems often rely on centralized authorities, paper-based documentation, and manual verification, leading to inefficiencies, delays, and lack of transparency. Our project, "zkVisa" leverages smart contracts and zero-knowledge proofs (ZKPs) to introduce a secure, decentralized mechanism for managing visa. By allowing immigrants to stake funds linked to a visa period and securely withdraw them only upon meeting verifiable time and location conditions, the system ensures compliance while preserving privacy. This not only reduces administrative overhead but also builds trust by making enforcement automated, auditable, and tamper-resistant.

Challenges we ran into

One of the key challenges we faced was implementing zero-knowledge proofs for location data without compromising user privacy. To tackle this, we wrote custom circuits in Circom that validate a user's presence at a specific location without revealing the exact coordinates. Integrating these zk proofs with our smart contract required careful coordination to ensure accuracy.