Voice Core Engineer

Aggregate function:  Technology
Business Area:  VT Netw. Strategy Archit. Eng.
Posting Country:  Portugal
Date Posted:  27 Apr 2026
Full Time / Part Time:  Full Time
Contract Type:  Permanent

At Vodafone, we’re working hard to build a better future. A more connected, inclusive and sustainable world. As a dynamic global community, it's our human spirit, together with technology, that empowers us to achieve this. 

We challenge and innovate in order to connect people, businesses, and communities across the world. Delighting our customers and earning their loyalty drive us, and we experiment, learn fast and get it done, together.

With us, you can be truly be yourself and belong, share inspiration, embrace new opportunities, thrive, and make a real difference.

Join Us

At Vodafone, we’re not just shaping the future of connectivity for our customers – we’re shaping the future for everyone who joins our team. When you work with us, you’re part of a global mission to connect people, solve complex challenges, and create a sustainable and more inclusive world. If you want to grow your career whilst finding the perfect balance between work and life, Vodafone offers the opportunities to help you belong and make a real impact.

The Senior Voice Core Engineering & Delivery Engineer plays a critical role in the strategic design, delivery, and evolution of Voice Core solutions across Vodafone Operating Companies. Acting as a senior technical authority, this role supports strategic technical analysis (e.g., RFQs, High-Level Designs, and solution evaluations) and contributes to end‑to‑end Voice Core architectures that span multiple markets.

The role combines deep hands‑on engineering with technical leadership. The Senior Engineer is expected to guide, mentor, and technically coach other engineers while ensuring high‑quality integration, testing, and delivery of complex Voice Core information systems within CS, IMS and 5G domains, in line with 3GPP standards and Vodafone global architecture principles.

What you’ll do

  • Lead the technical design and specification of Voice Core hardware and software solutions in alignment with customer requirements and Vodafone global standards.
  • Perform integration, deployment, and expansion of Voice Core information systems, including but not limited to MSS/MGW, STP, DRA, HSS, HLR, SBC, CSCF, TAS, UDR, AUSF, UDM, IBCF.
  • Execute and coordinate integration and acceptance testing for new software releases, ensuring backward compatibility and seamless coexistence with existing platforms.
  • Actively contribute to low‑level design specifications, solution documentation, and implementation guidelines for new Voice Core functionalities and services.
  • Support end‑to‑end project delivery, including planning, technical coordination, risk identification, and progress reporting for complex Voice Core projects.
  • Define and prepare Work Orders to support Change Management and Operations teams.
  • Provide technical leadership and on‑the‑job training, accelerating the competence development of junior and new engineers within the Voice Core domain.
  • Collaborate with cross‑functional stakeholders (architecture, operations, vendors, and customer teams) to improve service quality, network reliability, and customer experience.

Who you are

  • University degree in Telecommunications, Computer Science, Electronics, or equivalent.
  • Broad awareness of telecommunications and cloud ecosystems, including transport, IP networking, and system interoperability.
  • Experience with inter‑functional integrations between network elements, IT systems, and operational platforms.
  • Deep expertise in CS, IMS and 5GVoice Core architectures and information systems as defined by 3GPP standards.
  • Strong understanding of telecom protocols and call flows, including SIP, Diameter, SS7, MAP and related signaling technologies. Complementary protocols including HTTP2, JSON, SOAP, REST, TLS, SQL
  • Solid knowledge of the software and system lifecycle, including design, development, integration, testing, acceptance, deployment, and optimization.
  • Proven experience coordinating complex, multi‑vendor and multi‑market projects within a telecom environment.
  • Minimum 5 years of experience in a similar Voice Core engineering or delivery role.
  • Ability to work effectively in virtual, international teams and to communicate complex technical topics clearly to diverse audiences.

Not a perfect fit?

Worried that you don’t meet all the desired criteria exactly? At Vodafone we are passionate about empowering people and creating a workplace where everyone can thrive, whatever their personal or professional background. If you’re excited about this role but your experience doesn’t align exactly with every part of the job description, we encourage you to still apply as you may be the right candidate for this role or another opportunity.

What's in it for you

  • Hybrid Work Model - Flexible hybrid work model with 8-10 in-office days per month, managed by team leaders
  • Vodafone Products and Services - Employees get a mobile phone, free communication plan, data card, and various discounts on services and products
  • Recognition - Recognition programs for innovative, creative, high-potential employees and exemplary behaviors
  • Health and Well-being - Well-being Program offers nutrition and psychological consultations, webinars, workshops, and discounts on various services and products
  • Learning - Access to Communities of Practice and a customizable digital training platform with high-quality content (namely Harvard Business Publishing and Skillsoft)
  • Local and International Mobility - Internal recruitment with local and international rotation opportunities across departments and roles

Who we are

We are a leading international Telco, serving millions of customers. At Vodafone, we believe that connectivity is a force for good. If we use it for the things that really matter, it can improve people's lives and the world around us. Through our technology we empower people, connecting everyone regardless of who they are or where they live and we protect the planet, whilst helping our customers do the same.

Belonging at Vodafone isn't a concept; it's lived, breathed, and cultivated through everything we do. You'll be part of a global and diverse community, with many different minds, abilities, backgrounds and cultures. ;We're committed to increase diversity, ensure equal representation, and make Vodafone a place everyone feels safe, valued and included.

If you require any reasonable adjustments or have an accessibility request as part of your recruitment journey, for example, extended time or breaks in between online assessments, please refer to https://careers.vodafone.com/application-adjustments/ for guidance.

Together we can.

Vodafone is committed to attracting, developing and retaining the very best people by offering a motivating and inclusive workplace in which talent is truly recognised and rewarded. We are committed to promoting Inclusion for All with the belief that diversity plays an important role in the success of our business. We actively encourage everyone to consider becoming a part of our journey.