A Keycloak developer specializes in designing and implementing secure authentication and authorization systems using Keycloak, an open-source identity and access management tool. They handle user identity, access controls, and security features, offering single sign-on, two-factor authentication, and LDAP and social login support. Their duties include integrating Keycloak with existing applications, setting up user federations, managing roles and permissions, and ensuring the system's security. They also troubleshoot issues, develop custom providers or user federation SPIs, and often liaise with other developers and stakeholders. They must stay updated on security best practices and Keycloak updates.