An Internet Information Services (IIS) developer is responsible for designing, developing, and managing websites and applications on Microsoft's IIS platform. They configure and maintain servers, implement security measures, troubleshoot issues, and ensure optimal performance. Additionally, they often work with languages like ASP.NET and use databases like SQL Server. They also collaborate with other team members to integrate front-end elements with server-side logic. Their role requires a deep understanding of the IIS architecture, web protocols, and programming skills. They may also be involved in regular server updates and the deployment of new features or applications.