During September 2025, Kaiyou contributed to the nextcloud/richdocuments repository by focusing on backend bug fixes and code quality improvements. He addressed a deletion logic issue affecting guest user documents, ensuring that content persisted correctly when the user_id was null, which improved reliability for guest workflows. Kaiyou also enhanced maintainability by standardizing code formatting in TemplateManager.php, replacing tabs with spaces in SQL query construction to align with project-wide PHP standards. His work demonstrated attention to both functional correctness and long-term code health, leveraging skills in backend development, database management, and code formatting to deliver targeted, maintainable solutions within the project.