Over two months, Lecter1729 contributed to advanced cryptographic and field arithmetic features in Plonky3/Plonky3 and 0xPolygonHermez/zisk. In Plonky3/Plonky3, they implemented quintic extension field support for the Goldilocks field, introducing new traits and constants in Rust to enable more complex cryptographic protocols. For 0xPolygonHermez/zisk, Lecter1729 delivered native secp256k1 operations with modular inverse and square root, using both C and Rust for cross-language integration, and refactored circuit logic to improve maintainability. They also resolved a Keccakf circuit overflow, demonstrating depth in low-level programming, cryptography, and system design while enhancing reliability and performance across both repositories.