An HDFS (Hadoop Distributed File System) developer designs, develops, and deploys large-scale data storage systems and databases using Hadoop technology. They handle data processing, implement advanced algorithms for data analysis, and manage data loading from disparate data sets. They also optimize Hadoop's capabilities to improve data processing and storage. The developer troubleshoots complex issues in Hadoop clusters and ensures data security. They collaborate with data scientists and analysts to understand data needs and deliver high-quality solutions. Their work is essential for big data management, contributing to strategic decision-making in businesses.