Armin Ilg improved vertex reconstruction geometry for the IDEA Detector in the key4hep/k4geo repository, addressing gaps in the geometry definition that previously affected tracking precision and event reconstruction reliability. By refining the detector’s geometry using Geant4 and C++, Armin enhanced the accuracy of physics event reconstruction and reduced systematic uncertainties. The same geometry updates were applied to the ALLEGRO Vertex, ensuring consistency across detectors. Throughout the process, Armin demonstrated careful geometry modeling and maintained a clean, traceable git history. This work reflects a focused, technically sound approach to detector simulation and cross-repository collaboration within a high-energy physics context.