Manuel García developed and evaluated a user-facing Age-to-100 Calculator prototype in the i12vecaj/psp-25-26 repository, using Core Java and basic input/output techniques. The prototype collected a user’s name and age, then computed the year they would turn 100, providing a simple interactive experience. Manuel managed the full lifecycle of this feature, from rapid prototyping to disciplined removal of both source and binary artifacts, ensuring the main branch remained clean and maintainable. His approach emphasized repository hygiene and minimized technical debt, demonstrating careful change management and a focus on maintainability over long-term support for experimental features.