During March 2026, Taishan focused on enhancing the stability and correctness of JSON encoding within the swiftlang/swift-foundation repository. He addressed a critical bug in the JSONEncoder by clearing encoder storage in the returnEncoder method, which prevented crashes and potential data corruption caused by stale sharedSubEncoder state. His work involved advanced debugging and state management in Swift, ensuring that nil values were handled safely during dictionary encoding and that encoder caching did not leak invalid state. By leveraging his skills in Swift, backend development, and testing, Taishan improved reliability for downstream projects that depend on robust JSON encoding paths.