Yechan Kang integrated new GE21 detector chambers into the SegmentLinking/cmssw repository, focusing on enhancing the accuracy of detector simulations for high energy physics applications. Using C++ and leveraging expertise in detector simulation and geometry management, Yechan resolved geometry overlap issues that previously introduced systematic uncertainties in data analysis. The work streamlined downstream workflows and improved the maintainability of the simulation codebase, ensuring readiness for upcoming physics campaigns. By addressing both integration and overlap resolution, Yechan’s contribution provided a deeper level of technical refinement, supporting more reliable analyses and facilitating future development within the CMSSW detector simulation framework.