Core Growth Prompting (CGP) is an open-source AI-collaborative software design methodology that enables non-engineers to participate in software design through structured dialogue with AI. Rather than treating AI as an omniscient builder, CGP treats it as a verification partner. By emphasizing validation over AI decision-making, the methodology helps users create transparent, traceable, and logically consistent software designs while avoiding "black box" development. CGP was developed by a non-engineer in his 40s using a standard personal computer and AI collaboration. This experience led to the creation of a real-world system designed using CGP that is currently being prepared for patent application, demonstrating that meaningful software design is no longer limited to professional software engineers. The broader vision of CGP is to lower the barrier to software creation so that more people—not just programmers—can transform ideas into working systems. Inspired by the civic tech movement, CGP aims to empower individuals and communities to solve real-world problems through technology. The methodology is lightweight enough to be used on everyday hardware, including smartphones and older PCs (tested on a Core i5-7200U with 8GB RAM), making it accessible to a wider range of creators. To learn more about the ideas behind CGP, read the background story in Japanese or English. Explore CGP and discover a new way to design software through human–AI collaboration.