Developed and delivered a User Vehicle Management API for the fossguild/joynride repository, enabling users to associate and manage vehicles within the platform. The work involved designing and implementing new API endpoints using Go, updating the main API router to integrate these endpoints, and creating a dedicated vehicle service file. Data transfer objects and storage logic were introduced to support the full vehicle data lifecycle, ensuring data integrity and scalability. This backend development initiative established a robust data model for user-specific vehicle management, laying the groundwork for future features such as personalized vehicle catalogs and analytics, while adhering to authentication standards.