Our client is seeking a Mobile Voice Core Engineer to ensure the reliable operation, maintenance, and evolution of their Mobile Core network, which includes CS, EPC, IMS, and associated platforms. This full-time position involves 37.5 hours of work each week, with the opportunities available in Guernsey, Jersey, or the Isle of Man. The role reports to the Senior Mobile Engineer and collaborates with Mobile, Fixed, Transmission, and IP teams, as well as the Security Architect and Product teams. In this role, you will deliver high availability and performance for Packet Switched (PS) and Circuit Switched (CS) services, supporting technologies such as VoLTE and 5G Core. As a subject matter expert for IMS-based services, you will provide technical support for integration, troubleshooting, and optimisation. The successful candidate will also play a key role in ensuring that the network meets performance metrics and provides exceptional service quality.