In April 2025, Aleksandar Kajevic developed an Airplane Data Management API for the informacioni-sistem-za-aviokompanije repository, focusing on scalable CRUD operations for airplane records. He designed and implemented new Express.js routes and a dedicated controller in JavaScript, integrating them into the main Node.js server index to streamline fleet data operations. This foundational API unified airplane management endpoints, reducing integration friction and establishing a base for future fleet management features. The work emphasized maintainability and traceability, with clear commit documentation supporting rollback and audit needs. While the project scope was focused, the technical execution demonstrated solid backend engineering fundamentals.