Core Network Lead in Madrid, Madrid, Comunidad de at Jobgether

This position is listed on behalf of a partner company, which manages all applications and next steps. Our partner is looking for a Core Network Lead based in Spain.

As a Core Network Lead, you will drive the design, integration, and deployment of Full MVNO (Mobile Virtual Network Operator) core systems supporting global mobile connectivity. You will lead a specialized team of engineers and QA professionals, overseeing technical delivery from initial architecture through testing, commissioning, and operational handover. Working across voice, data, VoLTE, and messaging services, you will ensure reliable connectivity and seamless integration with mobile network operators worldwide. You will also take ownership of network architecture, signalling protocols, and compliance with telecommunications regulations across different markets. In a fully remote, international environment, you will collaborate with technical and operational teams to establish scalable engineering practices and deliver high-quality network infrastructure. This is an opportunity to combine deep telecommunications expertise with technical leadership while helping make global mobile connectivity more accessible to travelers.

• Technical team leadership: Lead, mentor, and manage a team of approximately five engineers and QA specialists, overseeing sprint planning, task allocation, technical reviews, and delivery across multiple global rollout projects.
• Engineering standards and processes: Establish engineering best practices, reusable integration templates, automated testing strategies, and standardized technical documentation and handover procedures.
• Global operator integrations: Lead technical integrations with host mobile network operators across signalling, packet core, voice, and messaging systems.
• Full MVNO architecture: Own the design, configuration, and implementation of core network components, including subscriber databases (HSS/HLR), packet core infrastructure, signalling routing, and messaging platforms.
• Signalling and protocol management: Oversee implementation, integration, and troubleshooting across the signalling stack, including Diameter and SS7, ensuring reliable communication between network components.
• End-to-end service readiness: Ensure the successful delivery of data, voice, and SMS services, covering session management, policy enforcement, data routing, VoLTE, legacy circuit-switched voice, and international interconnections.
• Mobile number portability: Design and validate number portability routing solutions that comply with country-specific regulatory requirements and enable reliable call routing.
• Regulatory compliance: Ensure compliance with telecommunications regulations in each market, including lawful interception requirements under ETSI ES 201 671 and TS 102 232, HI1/HI2/HI3 interfaces, and emergency service routing such as E112, 911, and 999.
• Quality assurance and testing: Collaborate with QA specialists to define and execute integration test plans, stress tests, and acceptance testing, ensuring systems meet performance, reliability, and operational requirements.
• Operational readiness and handover: Lead Operational Readiness Reviews and ensure newly deployed systems are thoroughly tested, documented, and transferred to the 24/7 operations team under the Build-to-Run model.
• Continuous improvement: Identify opportunities to improve integration efficiency, automation, network reliability, and delivery processes across concurrent rollout initiatives.

• Mobile core experience: At least five years of hands-on experience working with mobile core networks, including the design, implementation, integration, or operation of telecommunications infrastructure.
• Technical leadership: At least two years of experience leading engineers and/or QA specialists in an agile, project-based, or delivery-focused environment.
• Packet and voice core expertise: Strong working knowledge of packet core and voice core technologies, including HSS/HLR subscriber databases, policy and charging systems, VoLTE, and legacy circuit-switched voice.
• Signalling protocols: In-depth knowledge of Diameter, SS7, and SIP, with practical experience troubleshooting and integrating signalling systems.
• Messaging architecture: Experience with SMS architecture, routing, and interworking with other mobile network operators.
• MVNO integration: Understanding of Full MVNO architectures, host operator integrations, and the technical requirements for launching mobile services across multiple markets.
• Regulatory knowledge: Familiarity with telecommunications compliance requirements, mobile number portability, lawful interception, and emergency service routing across different jurisdictions.
• Delivery and project management: Proven ability to coordinate multiple concurrent rollout streams, prioritize technical work, and deliver complex integrations within agreed timelines.
• Quality and operational readiness: Experience with integration testing, stress testing, acceptance testing, technical documentation, and structured handovers to operational teams.
• Communication and collaboration: Strong communication skills, a collaborative mindset, and the ability to coordinate effectively with engineering, QA, and operations stakeholders in an international environment.
• Automation and DevOps experience (preferred): Familiarity with CI/CD pipelines, infrastructure as code tools such as Terraform or Ansible, containerization with Docker or Kubernetes, and automated signalling test frameworks.
• Vendor experience (preferred): Hands-on experience with core MVNO vendors such as Nokia, Ericsson, Mavenir, Oracle Communications, Cisco, Summa Networks, NetNumber, or XIUS.
• Cloud and virtualization (preferred): Experience with cloud-native or virtualized network functions running on AWS, Azure, Google Cloud Platform, or private cloud infrastructure.
• Educational background (preferred): A degree in telecommunications engineering, computer science, electrical engineering, or a related technical discipline.

• Competitive salary: Annual compensation varies by country, reflecting local market conditions and cost of living. The advertised ranges are:
  • United Kingdom: £89,600–£128,800
  • Ireland: €76,800–€110,400
  • Western and Southern Europe: €50,800–€116,117
  • Central and Eastern Europe and the Caucasus: €53,851–€88,291
• Location-based compensation: Your specific salary will depend on your country of residence, experience, and suitability for the role. Compensation expectations can be discussed during the initial recruitment conversation.
• Fully remote work: Work remotely from supported European locations, with flexibility to organize your working environment.
• Permanent, full-time employment: A long-term opportunity to lead critical telecommunications infrastructure initiatives and contribute to global connectivity.
• International collaboration: Work with a distributed team of professionals across multiple countries and contribute to services used by travelers worldwide.
• Technical ownership: Take responsibility for major network integrations, architecture decisions, and engineering delivery standards.
• Professional development: Expand your expertise in Full MVNO systems, mobile core technologies, automation, and global telecommunications infrastructure.
• Autonomy and trust: Work in an environment that emphasizes ownership, independent decision-making, and results rather than unnecessary bureaucracy.
• Growth opportunities: Develop your leadership capabilities and help scale engineering practices as the business expands.
• Inclusive working environment: Join an international organization that values diversity, equity, inclusion, and reasonable accommodations throughout the recruitment process.