A DataGuard developer specializes in Oracle DataGuard, a software product that manages, monitors, and automates data protection and disaster recovery in Oracle database environments. They create and manage physical and logical standby databases to ensure data availability, integrity, and reliability. They also implement failover and switchover processes, perform backup and recovery operations, and troubleshoot any issues related to DataGuard. Additionally, they work on improving performance and efficiency, ensuring seamless data replication and synchronization. They collaborate with other IT professionals to ensure database security and compliance with data regulations. Their role is crucial in minimizing data loss and downtime.