An AWS Data Pipeline developer designs, builds, and manages data workflows in the Amazon Web Services (AWS) environment. They create pipelines that move and transform data between different AWS services and on-premise data sources at specified intervals. Their tasks include setting up data-driven workflows (pipelines), troubleshooting data processing errors, managing and ensuring data consistency across multiple sources, and maintaining data security. They also monitor the performance of data flow, troubleshoot issues, and ensure the pipeline meets business requirements and goals. Their role is pivotal in enabling organizations to efficiently and effectively manage large volumes of data.