A Jersey Framework Developer designs and develops web services and applications using the Jersey framework, which is an open-source Java framework for developing RESTful Web Services in Java. They primarily use Jersey to simplify the development of RESTful services by providing a robust API, easy-to-use annotations, and support for JAX-RS (Java API for RESTful Web Services). Their tasks include coding, testing, debugging, and integrating Jersey with other Java frameworks. They also handle data transfer between the server and the client, troubleshoot issues, and ensure that the developed services meet the required performance, security, and functionality standards.