Staff Software Engineer (f/m/d) Virtual Network Functions

IONOS EN; Berlin; On-site; EUR 90,000 - 130,000; Full time

Benefits offered by this job

Subsidised canteen

Free drinks

Modern office near transport links

Employee discounts

Training and development opportunities

Health offers (sports and health)

Job summary

IONOS EN in Berlin seeks a Staff Software Engineer (f/m/d) to design, implement and operate the Virtual Network Functions powering our Cloud offerings. You will write Golang services, review code, and work across architecture, deployment and day-to-day operations on Kubernetes.

Join a team that embraces AI-assisted development, open networking tooling and close collaboration with other product teams. Flexible hours, modern offices, and strong growth opportunities across a leading European cloud

Qualifications

• Proficiency in Golang and/or C/C++, including AI-assisted development.
• Hands-on experience with Kubernetes architecture and operations; knowledge aligned with CKA principles.
• Knowledge of TCP/IP and networking technologies like Open vSwitch/OpenFlow/VXLAN/VRF/eBPF.
• Experience with cloud environments and virtualization technologies like QEMU/KVM.
• Experience with GNU toolchain (gcc, gdb, make), git and the Linux CLI.
• Experience with Linux system administration and automation.

Responsibilities

• Develop and support VNF offerings on IONOS Cloud using diverse technologies.
• Design new features and adopt new technologies for VNF components.
• Write, test and review Golang services for VNFs; use AI-assisted tooling in daily work.
• Deploy, operate and troubleshoot VNF workloads on Kubernetes; manage cluster ops and monitoring.
• Collaborate with other teams to integrate VNFs with IONOS products.

Skills

Golang

C/C++

AI-assisted development

Linux CLI

Kubernetes operations

Networking basics

Tools

Kubernetes

QEMU/KVM

GNU toolchain

git

Job description

Staff Software Engineer (f/m/d) Virtual Network Functions

About IONOS

At IONOS, we don't just manage servers - we shape the digital future for more than 6.2 million customers worldwide with our solutions. As Europe's leading hosting provider and a pioneer in independent cloud solutions, we are building next-generation infrastructure - from sovereign cloud architectures and high-performance GPU clusters to integrated AI automation tools.

What drives us is digital sovereignty for Europe and real impact for small and medium-sized businesses (SMBs) as well as large enterprises. We work in agile teams, rely on transparent structures, and believe that excellence and innovation only emerge through true team spirit.

Ready for your next step? Become part of IONOS and grow with us.

The IONOS Cloud VNF Development team is seeking a highly motivated and experienced software engineer.

The VNF Development team designs, develops and maintains the Virtual Network Functions (VNF) behind IONOS Cloud's network offerings. These products serve both our external customers and other internal IONOS teams. We build our VNFs in Golang and run them on Kubernetes, so the team works across the whole lifecycle: architecture, implementation, deployment and day-to-day operations. As part of the team, you'll play a crucial role in shaping and running these products.

We are looking for someone to join our team and work with us on providing the best VNF products possible.

Tasks

• Developing and supporting our multiple modern, scalable and high-performance Virtual Network Functions (VNF) offerings of IONOS Cloud using a range of diverse technologies.
• Designing new features and adopting new technologies (both hardware and "software defined") on different components of the VNF infrastructure.
• Writing, testing and reviewing Golang services for our VNFs, using AI-assisted tooling as part of your daily development workflow.
• Deploying, operating and troubleshooting VNF workloads on Kubernetes, including cluster operations, upgrades, monitoring and debugging network issues in production.
• Cooperating with other teams to ensure the smooth integration of new Virtual Network Functions with different IONOS products.

Qualification

• Proficiency in Golang and/or C/C++, including AI-assisted development.
• Hands-on experience with Kubernetes architecture and operations; knowledge aligned with CKA (Certified Kubernetes Administrator) principles.
• Knowledge of the TCP/IP protocol family and networking technologies such as Open vSwitch, OpenFlow, VXLAN, VRF and eBPF.
• Experience with cloud environments and virtualization technologies like QEMU/KVM.
• Experience with GNU toolchain (gcc, gdb, make, etc.), git and the Linux CLI.
• Experience with Linux system administration and automation.
• Nice to have: Linux kernel networking internals, VPP and DPDK.
• Flexible working hours through trust-based working hours.
• At some locations a subsidised canteen and various free drinks.
• Modern office space with very good transport connections.
• Various employee discounts for activities and products.
• Employee events such as summer and winter parties, as well as workshops.
• Numerous training and development opportunities.
• Various health offers, such as sports and health courses.

Application Note

We value diversity and welcome all applications - regardless of, for example, gender, nationality, ethnic or social origin, religion, disability, age as well as sexual orientation and identity, physical characteristics, marital status or any other irrelevant factor subject to applicable law.