IONOS EN

Software Engineer Software-Defined Networking

In short

Software engineer role on IONOS Cloud's SDN Development team, building and maintaining the high-performance Software-Defined Networking stack that connects customers' VMs and cloud services. Covers Linux kernel networking, virtual switching, control plane, and automation tooling using C/C++, Golang and Python. Requires deep experience with Linux kernel networking internals, TCP/IP and BGP, Open vSwitch/OpenFlow/VXLAN/eBPF, and virtualization (Kubernetes, QEMU/KVM, VirtIO). Hybrid work model at a German location, posted by IONOS, Europe's leading hosting provider.

About the Role
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.
Responsibilities
•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/OpenFlow 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.
Requirements
•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, OpenFlow, 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.
Conditions / Benefits
•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.

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