During July 2025, W worked on the oasisprotocol/oasis-sdk repository, focusing on improving quantity handling in TypeScript. They addressed a bug in ts-web/core by implementing stricter input validation for quantity conversion, specifically rejecting negative BigInt values. By introducing a guard that throws a RangeError when negative values are encountered, W ensured that only valid, non-negative quantities are processed, which prevents invalid representations and reduces the risk of downstream transaction errors. This work involved BigInt manipulation and robust error handling, resulting in improved test coverage and greater stability for transaction processing within the TypeScript codebase of oasis-sdk.