Core Engineer

This role sits within the Mission Critical Test and Certification team of a leading global tech company’s Networks Europe division. The team is driving entry into the Public Services domain across Europe. This role requires 5 days per week onsite in Berkshire office. We are looking to hire a senior telecom Core Engineer with extensive background and experience in IMS and VoLTE, any vendor (i.e. Ericsson, Nokia, Mavenit), and ideally someone who is well rounded; Design/Architecture, Testing, Integration, O&M would be preferable. As an MCX Engineer, you will work across the Test and Delivery teams under the guidance of Test and Service Delivery Managers. You’ll play a pivotal role in ensuring the performance, reliability, and availability of our solutions—meeting customer expectations, contractual milestones, and service level agreements (SLAs). Joining our team means becoming part of a group of highly skilled technical specialists who define and deliver industry-leading MCX solutions, supported by strong collaboration with colleagues across Europe and at our global headquarters. Key Responsibilities Act as a technical expert in IMS , applying analytical skills to troubleshooting, root cause analysis, and end-to-end testing. Provide solution expertise and guidance for MCX Client and Application Test Strategy and Test Plans across network elements and software releases. Execute Functional, Performance, Accessibility, and Compatibility test plans. Track and report test progress accurately within defined project timelines. Validate test cases, upgrade procedures, troubleshooting guides, and documentation to ensure consistent and reliable test execution. Conduct detailed analytics and fault investigations to resolve feature and performance issues within SLAs. Provide continuous feedback and recommendations on training and development for yourself and fellow engineers. Execute MCX Client porting and verification testing to support R&D in meeting release criteria. Produce detailed test progress reports and performance logs. Manage trouble tickets through to resolution, ensuring comprehensive documentation for R&D investigation and implementation of recommendations. Offer technical support during Sandbox testing, providing analysis, feedback, and logs to third parties for solution development or integration. What We’re Looking For Strong background in 4G/5G Core technologies, particularly Voice, Video, and Data services for users and applications. Deep expertise with MCX Client applications and SDK solutions on Android (GMS, non-GMS, Android Go), iOS, Linux, and Windows OS. Proficiency with LTE testing tools (Wireshark, IXIA, Viavi, Spirent, XCAL, XCAP, QXDM, Jira, HPQC, Logcat/Putty); experience with MCPTT QCIs is a plus. Experience in software lifecycle testing for VNF deployments on VMware. Knowledge of client software deployment methods via OTA and EMM. Proven ability to perform end-to-end troubleshooting for LTE and TETRA networks and call flows. Strong understanding of 3GPP specifications and Mission Critical features. Excellent presentation, communication, and interpersonal skills in written and spoken English. Engineering degree (or equivalent experience) in Computer Science, Electronics, Telecommunications, or a related field. Familiarity with GCF and other testing standards for client certification. Flexibility to support on-call rotations as needed. Willingness to work on-site with customers for extended project support periods. What Success Looks Like A self-motivated, driven professional who thrives as part of a small team of test experts. Ability to execute complex testing activities to defined project and test milestones. Collaborative approach, working with PMO functions to report progress and address project risks effectively. Strong and lasting working relationships with customers and partners. Acts as the subject matter expert for deep technical investigations across end-to-end LTE and TETRA architectures. Flexibility and reliability to support on-call duties and customer site engagements as required.

Location: Slough, UK, GB

Posted Date: 10/31/2025