A Microkernel developer designs, implements, and maintains microkernel systems, a type of operating system architecture where the kernel provides minimal services such as communication, drivers, and memory management. They focus on creating a compact and efficient kernel, with other functionalities running in separate processes, to improve system reliability and flexibility. They also debug and resolve issues, optimize performance, and integrate new technologies. Their work involves extensive programming, testing, and system architecture design. They collaborate with other developers and software engineers to ensure compatibility and interoperability between different software components.