A CXF developer primarily works with Apache CXF, an open-source services framework, to develop and manage web services. They use SOAP, RESTful, and other protocols to design web service applications. Additionally, they handle the integration of these services into larger systems, ensuring seamless connectivity and functionality. They also troubleshoot and fix any issues that arise with the web services, optimizing their performance. Other responsibilities may include creating technical documentation, collaborating with other developers, and maintaining a strong understanding of the latest technologies and industry trends. Their ultimate goal is to deliver robust, efficient, and scalable web services.