Software Engineer; f​/m​/d) Software-Defined Networking

The IONOS Cloud SDN Development team is seeking a highly motivated and experienced software engineer. The SDN Development team designs, develops and maintains the high-performance Software-Defined Networking (SDN) stack of IONOS Cloud: the networking foundation that connects our customers' virtual machines and cloud services. Our work spans the Linux kernel networking layer, virtual switching and the control plane. We use a range of technologies, from C/C++ and Golang for performance-critical components to Python for tooling and automation.

• Developing and supporting the scalable, high-performance SDN stack 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 SDN infrastructure.
• Writing and debugging C/C++ and Golang/Python code across the SDN data plane and control plane, from Linux kernel networking and eBPF to Open vSwitch/Open Flow pipelines.
• Building Python tooling and automation for testing, deploying and operating the SDN stack, and troubleshooting network issues in virtualized environments (QEMU/KVM, VirtIO).
• Cooperating with other teams to ensure the smooth integration of new SDN features with different IONOS products.

• Proficiency in C/C++ and/or Golang, plus Python, including AI-assisted development.
• Experience with Linux kernel networking internals.
• Knowledge of the TCP/IP protocol family and routing protocols like BGP, plus networking technologies such as Open vSwitch, Open Flow, VXLAN, VRF and eBPF.
• Experience with cloud environments, Kubernetes and virtualization technologies like QEMU/KVM and VirtIO.
• Experience with the GNU toolchain (gcc, gdb, make, etc.), git and the Linux CLI.
• Experience with Linux system administration and automation.
• Nice to have: experience with VPP and DPDK.

• Hybrid working model.
• Flexible working hours through trust-based working hours.
• At some locations a subsidized 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.