https://www.hackquest.io/ko/hackathons/Mantle-Global-Hackathon-2025?utm=RocketPunch LatticA is a privacy-preserving payroll and transaction system built on an auditable dark pool. It is designed for teams and organizations that want to move payroll and sensitive financial flows on-chain without exposing compensation data publicly, while still remaining capable of responding to audits and regulatory requests. The system is based on a fork of the Mezcal dark pool architecture and extends it with a cryptographic audit layer that preserves privacy by default and enables compliance only when explicitly authorized. Traditional ZK-based dark pools rely on hash-based identities, typically using a hash of a secret key as the user identifier. While this approach is efficient, it makes identity proofing, encrypted communication, and structured audit responses effectively impossible. LatticA addresses this limitation by introducing a dual-structure proof system that supports both privacy and accountability. Instead of simple hash-based addresses, we use elliptic curve public keys derived from secret keys, enabling public-key encryption and verifiable identity linkage without revealing information on-chain. At the core of the audit system is an RLWE-based encryption module. Every shielded transaction generates an encrypted audit witness that is cryptographically bound to the zero-knowledge proof used for the transaction itself. These audit records are unreadable by default and cannot be accessed by a single party. Decryption requires threshold cooperation, meaning that at least two authorized auditors must jointly reconstruct decryption capability. This ensures that no single operator, admin, or infrastructure provider can unilaterally deanonymize users or inspect payroll data. The RLWE audit layer is parameterized to balance security and performance. We use a polynomial degree of 1024 and a large prime modulus to ensure post-quantum security properties, with controlled nois