Core Engineer (Core Network Engineering team)

What you will do

Our client is an innovative technology company delivering global cellular and IoT connectivity solutions with operator‑grade reliability for mission‑critical applications. They provide redundant, low‑latency connectivity across 190+ countries through partnerships with hundreds of operators and their own MVNO core network, local breakouts and regional data servers. Key offerings include connectivity management platforms (SIM/eSIM lifecycle, provisioning, automation), product for mission‑critical IoT and product for remote operator profile management. Services span Fixed Wireless Access, network security (DDoS protection, traffic monitoring, malware prevention), and tailored solutions for healthcare (IoMT), energy & utilities, transportation & logistics, automotive, payments and remote workforce connectivity. Emphasis is on high availability, regulatory compliance and scalability for global enterprise deployments. A Careers section indicates the company is expanding its team and seeks professionals ready to work on high‑impact, operator‑facing projects.

Core Engineer (Core Network Engineering team)

We offer:

• An exciting and challenging workplace with great skill and knowledge development opportunities.
• The opportunity to join a team of highly professional specialists in an international environment.
• The opportunity for professional development within a reputable international innovative and growing company.
• Salary level: 1400-1600 EUR gross per month
• Social benefits
• 200 EURO monthly Wolt food allowance
• Medical insurance
• Free mobile services with Tele2
• Car parking spot

Responsibilities:

• The role is technical and operational
• You will troubleshoot real network issues across 3G, 4G, and 5G Standalone, own tickets end-to-end, and lead integrations and projects on a live production network
• We are a focused team that moves fast and takes full ownership of activities end to end.
• You will grow quickly into independent contributors

Requirements:

• Deep understanding of MNO/MVNO architecture and end-to-end GTP flow design

• Complete familiarity with 3GPP standards across 2G/3G/4G and 5G, including:

• GTP-C / GTP-U, CUPS - bearer lifecycle, session management, data plane flows

• Diameter & Radius - routing, realms, application IDs (Gx, Gy, S6a), AAA flows

• 5G-SA architecture - AMF, SMF, UPF, NRF, PCF - hands-on or advanced lab experience

• Strong understanding of GRX routing and IPX interconnect operations

• Understanding of roaming processes and procedures: IR.21,IPX, and GRX operations

• Hands-on experience

• PGW - configuration, troubleshooting, session management

• PCRF- Gx interface, policy management

• GTP Proxy - GTP-C interception, roaming traffic steering

• Diameter - routing configuration, signaling troubleshooting, experience analyzing Diameter flows.

• Radius - AAA flows, authentication, and accounting troubleshooting, experience analyzing Radius.

• Understanding of roaming processes and procedures (IR.21, familiarity with IPX and GRX operations).

• Working with monitoring tools

• Our engineer should have the following skills:

• Ability to design, scale, and integrate a network element into a live network.

• Hands-on experience in integration between network elements.

• Comfortable working under pressure during live network incidents

• At least 3 years of practical experience as a core engineer.

• Familiar with APIs and basic scripting (Python or similar).

• 24x7 On-call duty.

• Team player