Worked on the heremaps/xyz-hub repository to enhance large payload support and improve backend reliability. Upgraded the Vert.x framework to increase stability and modified payload handling to allow unlimited body sizes, addressing production needs for high-throughput feature collections. Expanded integration testing by generating and validating ~12MB payloads, using Java for both backend development and test automation. Clarified documentation within BaseHttpServerVerticle to specify unlimited body size semantics, improving maintainability and reducing ambiguity for future contributors. Focused on API development, integration testing, and backend improvements, these changes collectively reduced risk around large data transfers and strengthened the codebase’s long-term clarity.