A Hydrographs/Hydroflow developer designs, develops, and maintains applications using Hydroflow, a programming language for stream processing. They work with large volumes of real-time data and create hydrographs - visual representations of water flow over time. They manage data ingestion, processing, and output, ensuring efficient data stream management. They handle error tracking, debugging, and resolving performance issues. The developer also works on improving system functionalities by updating, improving, and optimizing the existing codebase. They work closely with other team members, like data scientists and engineers, to integrate and deploy models for data analysis and prediction.