A Fortran developer designs, develops, and maintains software applications using the Fortran programming language. They write efficient, testable, and scalable code to implement application functions or solve complex computational problems, often in scientific computing or engineering fields. Their responsibilities also include debugging and troubleshooting software, optimizing code for performance, and ensuring its portability across different platforms. Additionally, they document their code for future reference and collaborate with other team members to integrate individual components into a unified system. They may also update legacy Fortran systems to modern standards.