A salvaged control board from his late grandfather’s discarded prosthetic device. Basic sensors repurposed. A casing assembled from available materials. Hours of trial, error, and recalibration. The result, still rough but functional, is a portable defibrillator powered through a hybrid system—bioelectric input supplemented by stored charge. It responds to voice prompts. More importantly, it contains a simple but critical safeguard: it analyses cardiac rhythm and will only d