A Greenplum developer specializes in creating and managing data solutions using Greenplum Database, a massively parallel processing (MPP) database server. Their responsibilities include writing and optimizing SQL scripts and PL/Python functions, developing data models, and creating ETL processes. They also work on data warehousing, big data management, and performance tuning to ensure efficient data processing and retrieval. They design and implement security measures, troubleshoot issues, and collaborate with other team members to meet business needs. Additionally, they stay updated with the latest Greenplum developments and apply best practices to optimize data storage and processing.