Ziyi Yang developed a high-precision fee calculation feature for the Universal Router SDK in the Uniswap/sdks repository, focusing on enabling fractional basis points for trades. By implementing PAY_PORTION_FULL_PRECISION support, Ziyi enhanced pricing accuracy and routing reliability, which benefits both traders and developers working with complex swaps. The work involved advanced TypeScript programming, precision arithmetic, and thorough testing to ensure robust integration with existing smart contract logic. Although the contribution was limited to a single feature over one month, the depth of the implementation demonstrated strong blockchain development skills and a clear understanding of the requirements for reliable decentralized trading infrastructure.