Worked on the jami-fhir-jp-wg/jp-core-v1x repository to enhance data quality and documentation for FHIR interoperability, focusing on the JP_Patient resource. Addressed two key bugs by correcting data definitions and country code notations in FSH, and updated postal code formatting to meet validation standards. Improved multilingual data handling by clarifying the nameRepresentationUse documentation, adding romanized notation alongside kanji and kana. Emphasized clear documentation and commit traceability to support future maintenance and onboarding. Utilized skills in Data Modeling, Data Validation, and FHIR, with changes aimed at improving data accuracy, interoperability, and integration with external systems and analytics.