Job Description Capgemini Engineering, a global leader in engineering services, brings together teams of engineers, scientists, and architects to help the world’s most innovative companies unlock their potential and contribute to a better future. Join our team and advance your career at a company offering growth opportunities where you can make a difference—and where no two days are ever the same! **We are seeking a Senior Engineer with deep end-to-end technical expertise in mobile data roaming and its various use cases across 3G, 4G, and 5G, oriented toward international business.** **Key Responsibilities:** * Develop and define technical and evolution requirements for the mobile core and its Value-Added Services (VAS), including monitoring and transport of data roaming, GTPv1, GTPv2, GGSN/PGW, DBO, and GTP proxy. * Lead technical projects in direct contact with customers, vendors, and stakeholders. * Provide documentation and training for internal TGS units and customers. * Provide Level 3 support to Operations. * Lead and define Proof-of-Concepts (PoCs) for emerging technologies. * Collaborate with multiple vendors on the design and implementation of data roaming solutions. * Lead the RFx process for vendor selection. * Manage projects end-to-end to ensure timely delivery and proactively flag any risks. **Required Qualifications:** Degree in Telecommunications, Communication Systems, or related field; solid understanding of IP networks and 3G/4G/5G protocols. * Minimum 8 years of proven experience in Engineering + Operations, leading cross-functional and international projects. * Proven experience working for a Mobile Network Operator (MNO). • Demonstrated experience in deployment, engineering, configuration, delivery, and operation of various mobile network elements and protocols: GTPv1, GTPv2, PGW/GGSN, SGW/SGSN, DNS, GTP proxy, firewalls, VAS, IP protocol, DPI, BGP, static routing, NAT, CGNAT, CUPS, and 5G Core. • Experience in bare-metal, virtualized, and public cloud environments, Kubernetes, and private clouds. * Solid understanding and analysis of standards for packet core GTPx, DNS, VoLTE, and 5G. * Knowledge of DNS protocols for APN resolution and internet navigation. * Experience using signaling monitoring and tracing tools. * Experience drafting and evaluating RFx documents. * Knowledge of 5G and MEC architectures—experience is a plus. * Familiarity with private 4G and 5G networks. * Understanding of 3GPP and GSMA specifications, packet core/EPC, mobile network protocols, and architecture. Fluency in Spanish and English (advanced level required). Location: Madrid. Work Modality: 90% Remote Work Job Description – Grade Specific We value all applications. We offer an extensive range of training opportunities—including classroom, online, and certification programs. Even if you don’t meet 100% of the desired qualifications, we’d love to meet you! Candidates with a disability certification will be positively considered, in line with our inclusion and diversity policy. Our commitment to inclusion and equal opportunity is reflected in our Equality Plan and Code of Ethics, which guarantee professional development and fair hiring practices within a discrimination-free environment—regardless of ethnicity, nationality, social origin, age, sexual orientation, gender expression, religion, or any other personal, physical, or social circumstance. What You’ll Love About Working Here: We offer a comprehensive suite of Development and Work-Life Balance initiatives, including but not limited to: Onboarding support through our Buddy Program. 24 vacation days + 2 personal days + December 24th and 31st + option to purchase up to 7 additional vacation days per year. Continuous learning: access to MyLearning, Capgemini University, Digital Campuses, and Professional Communities. Platforms available include Coursera, Udemy, Pluralsight, Harvard Manager Mentor, and EF Education First for language learning (English, French, German, etc.)—and more! FlexAbroad: work remotely from another country for up to 45 days. Why Capgemini? Capgemini is a global leader in transforming and managing clients’ businesses by harnessing the full power of technology. We are a responsible and diverse company, and an international leader in IT and Engineering services, with over 360,000 professionals across 50+ countries. Rewrite your future. Join our team! www.capgemini.com/es-es **#LI-PE1** Ref. code 377295-es_ES Posted on 11 Dec 2025 Experience level Experienced Professionals Contract type Permanent Location Madrid Business unit Engineering and R&D Services Brand Capgemini Engineering Professional communities Products & Systems Engineering