During September 2025, Hayakawa updated the Announcements section of the yaizu-city/opendata repository to support the launch of the 'Let's Measure Vegetable Intake' health initiative. Using HTML and front-end development skills, Hayakawa replaced outage-resolution messaging with proactive health content, promoting Veggie Check devices and informing citizens about a new public health service. The update aligned with Yaizu City’s Smart City objectives by shifting the content strategy toward citizen engagement and health awareness. Delivered as a focused, single-commit change, the work demonstrated careful risk management and provided clear business value, though the scope was limited to one feature and no bug fixes.