An AppFabric developer works on Microsoft's set of integrated technologies, AppFabric, which helps to build, scale, and manage applications. They are responsible for developing and managing applications for both on-premise and cloud environments. Tasks include creating service bus messages, managing workflows and distributed cache control, and troubleshooting issues. They ensure smooth communication between services and applications, enhance the application's reliability, and maintain its high availability. Adept in .NET framework, they leverage AppFabric's capabilities for better application lifecycle management. They also work closely with other IT professionals to design and implement robust solutions.