Filip Laurentiu

I solved the Mental Poker challenge with a fully playable, drop-tolerant implementation. It uses cryptographic shuffling (Bayer-Groth) for fair card dealing and MPC (the SPDZ protocol) to securely select a community card, ensuring the game remains trustless, fast, and resilient even if players drop out.

Drop-tolerant: Game continues seamlessly if players exit.
On-chain fairness: Starknet smart contracts handle commitments, actions, and funds with low latency and cost.
True randomness: Future block hashes and user entropy guarantee unpredictable outcomes.

A practical, end-to-end solution making provably fair, decentralized poker a reality.

I designed and implemented a privacy-preserving cryptographic protocol enabling confidential fund transfers on a public blockchain network. I utilized zero-knowledge proof (ZKP) technology, STARK, and stealth addresses to ensure transaction privacy without compromising on-chain verifiability. I also developed smart contracts and off-chain components to handle proof generation, verification, and secure fund movement while maintaining scalability.

1st Place Starknet Hackathon: ZK Token Mixer
I built a privacy-preserving token mixer on Starknet using Cairo and zero-knowledge proofs, enabling fully anonymous transactions while maintaining verifiable correctness. Users deposit tokens into a shared pool and withdraw to new addresses with no on-chain link between sender and receiver.

ZK-powered: Proofs ensure validity without revealing identities or amounts.
Trustless: No central authority, math guarantees privacy.
Scalable: Leverages Starknet’s low-cost, high-speed transactions.
A first-place hackathon winner, proving that privacy and scalability can coexist on Ethereum L2s.