(1) Vendor needs to provide custom events calendar web application hosting service. Digital firms to design and develop a custom, embeddable calendar web application. The solution must support multiple independent calendars, advanced filtering, mobile–first design, user–generated event submissions with moderation, and flexible embedding options for integration across city websites. The calendar system will be internally hosted by the city, built using modern open–source technology, and fully owned. Mobile–first, WCAG 2.1 aa–compliant public interface. The public calendar interface must be mobile–optimized, fast, and WCAG 2.1 aa compliant. Hosting on modern cloud platforms. Relational database PostgreSQL preferred.