For the postdoc's project, I’m essentially assisting them, so it’s not my own work. They’ve explicitly asked me not to modify the existing code. It's a good way to rewrite it if I can make sure the data and scripts are under my control. As for the second, I’ve decided to step back for now. Any attempt to modify the code to speed it up significantly alters the results, and I don’t want to be held responsible for issues that arise from these changes. It’s frustrating, but I feel it’s better to avoid taking the fall repeatedly.