Worked on the nautechsystems/nautilus_trader repository to enhance identifier validation within the backend system, focusing on improving data integrity and interoperability. Developed and delivered a feature that transitioned PositionId validation from ASCII-only to UTF-8, allowing the system to accept a broader range of identifiers from external sources. This change involved refining the validation logic in Rust, specifically updating PositionId::new_checked to use UTF-8 checks while maintaining performance and correctness. The work aligned with ongoing system design goals, reduced downstream errors related to character encoding, and laid the foundation for broader Unicode support throughout the trading platform’s codebase.