A CA SiteMinder developer primarily works with CA SiteMinder, a centralized web access management system that enables user authentication and single sign-on, policy-based authorization, identity federation, and auditing of access to web applications and portals. Their responsibilities include developing and implementing security policies, integrating applications with SiteMinder, troubleshooting and resolving issues related to SiteMinder. They also handle upgrades, patches, and general maintenance of the SiteMinder platform. Furthermore, they collaborate with other IT professionals to ensure system security and efficiency, and may also provide technical support and training to users.