Midnight Shield: Protect That Data prompt

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Midnight Network Challenge: Protect That Data

This is a submission for the Midnight Network "Privacy First" Challenge - Protect That Data prompt

What I Built

Demo

https://github.com/zeeshan12312/midnight-shield-protect-data/

How I Used Midnight's Technology

Compact Language for Zero-Knowledge Circuits
I leveraged Midnight's Compact language to create privacy-preserving identity verification circuits. The core circuit (identity.compact) implements zero-knowledge proofs that verify age eligibility (18+) and location validity without revealing the actual values:

circuit IdentityVerification {
    private field age;
    private field locationCode;
    private field salt;

    public field commitment;

    constraint age >= 18;
    constraint locationCode >= 1 && locationCode <= 195;
    constraint commitment == pedersenHash(age, locationCode, salt);
}

MidnightJS SDK Integration
The DApp uses MidnightJS for client-side proof generation and blockchain interaction. Key implementations include:

Proof Generation: Converting user inputs into cryptographic proofs using Midnight's proving system
Commitment Creation: Using Pedersen hashing for secure data binding
On-chain Verification: Deploying and interacting with Compact contracts on Midnight network

Privacy-Preserving Architecture

The application implements Midnight's privacy-first design principles through:
Client-side Proving: All sensitive computations happen locally
Cryptographic Commitments: Data is bound cryptographically without exposure
Zero-Knowledge Verification: Proofs reveal only the minimum necessary information

Data Protection as a Core Feature

Privacy by Design Architecture
Data protection isn't an afterthought—it's the fundamental architecture of the DApp. The entire system is built around the principle that personal data never leaves the user's device in plaintext.

Zero-Knowledge Identity Verification
The core feature enables users to prove identity criteria without data exposure:

Age Verification: Proves age ≥ 18 without revealing actual age
Location Eligibility: Confirms valid jurisdiction without exposing exact location
Unlinkable Proofs: Multiple verifications cannot be correlated to the same user

Cryptographic Data Binding
Using Pedersen commitments, the DApp creates tamper-proof bindings between user data and proofs while maintaining complete privacy. The commitment scheme ensures data integrity without compromising confidentiality.

Decentralized Verification
All verification happens on-chain through Midnight's privacy-preserving smart contracts, eliminating the need for trusted third parties while maintaining complete data protection.