During February 2025, Lucía Pelegrina enhanced heavy neutral lepton (HNL) decay modeling in the SBNSoftware/sbncode repository by implementing anisotropic decay distributions, polarization handling, and three-body angular rotations within C++. She integrated the CLHEP random number generator and updated Lorentz vector manipulations to improve simulation fidelity, specifically addressing MuPi channel anisotropies and disabling interference in two-body decays. In SBNSoftware/sbndcode, she aligned HNLMakeDecay configuration files using FCL to ensure reproducibility and maintainability across repositories. Lucía’s work demonstrated depth in configuration management and event generation, resulting in more accurate and consistent HNL decay simulations for particle physics analyses.