Staff Software Eng, Kernel Network

At eBay, we're more than a global ecommerce leader — we’re changing the way the world shops and sells. Our platform empowers millions of buyers and sellers in more than 190 markets around the world. We’re committed to pushing boundaries and leaving our mark as we reinvent the future of ecommerce for enthusiasts.

Our customers are our compass, authenticity thrives, bold ideas are welcome, and everyone can bring their unique selves to work — every day. We're in this together, sustaining the future of our customers, our company, and our planet.

Join a team of passionate thinkers, innovators, and dreamers — and help us connect people and build communities to create economic opportunity for all.

About the team and the role:

The Traffic team is responsible for the reliability, performance, and security of network traffic across our edge and core infrastructure. We design and operate high-throughput, low-latency data paths, evolve our kernel and userspace networking stack, and build observability that powers real-time insight and rapid incident response. Our work spans L4/L7 load balancing, service mesh/data plane, packet processing, congestion control, routing, and traffic policy enforcement.

We are seeking an experienced engineer (10+ years) with deep expertise in the Linux kernel networking stack and production observability to lead design and implementation of high-performance data planes and visibility tooling. You will own system-critical components, influence architecture across teams, and mentor engineers while delivering measurable improvements to throughput, latency, and reliability.

What you will accomplish:

• Design, implement, and optimize kernel-level networking components (TCP/UDP, QUIC, congestion control, sockets, netfilter, XDP/AF_XDP, eBPF) for high-scale production environments

• Build and evolve data planes for L4/L7 traffic management, including load balancers, proxies, NAT, firewalling, rate limiting, and traffic shaping

• Develop robust observability for the networking stack: eBPF-based telemetry, tracing, packet capture, flow logs, performance counters, and SLO/SLA instrumentation

• Lead initiatives to reduce tail latency, improve throughput, and decrease resource utilization via kernel/userspace tuning, scheduling, NUMA/IRQ affinity, offloads, and memory management

• Architect and deploy scalable traffic systems across multi-region, multi-tenant environments with zero-downtime rollouts and rapid incident recovery

• Partner with SRE, Security, and Platform teams on traffic policy, DDoS mitigation, TLS/PKI, and compliance requirements

• Drive roadmap, technical strategy, and cross-functional execution; provide technical leadership and mentorship to the team

• Conduct rigorous benchmarking and capacity planning; define performance baselines and regression gates

• Own production health: participate in on-call rotations, root-cause analysis, and corrective action plans

What you will bring:

• 10+ years of software engineering, with significant experience in Linux kernel networking and high-performance systems.

• Expert-level knowledge of kernel networking subsystems: sockets, TCP/IP stack, routing, netfilter/iptables/nftables, XDP/AF_XDP, eBPF.

• Strong systems programming skills in C/C++ and familiarity with Rust or Go for userspace components.

• Proven experience building and operating large-scale traffic systems (load balancers, proxies, packet processors) in production.

• Hands-on expertise with observability: metrics, logs, tracing, eBPF probes, perf/tracepoints, tcpdump, pcaps, and performance analysis tools.

• Deep understanding of performance tuning: NIC offloads, DPDK or kernel-bypass techniques, IRQ/queue management, NUMA, memory allocators, lock contention, and scheduler behavior.

• Solid knowledge of L4/L7 protocols (TCP, QUIC, TLS, HTTP/2/3), congestion control, and transport/security internals.

• Experience with cloud or bare-metal environments, container orchestration (Kubernetes), service discovery, and service mesh patterns.

• Strong debugging skills across kernel/userspace boundaries; ability to analyze crashes, deadlocks, and performance pathologies.

Preferred Qualifications:

• Contributions to Linux kernel, eBPF tools, or relevant open source projects (Cilium, Envoy, NGINX, HAProxy, Calico, DPDK).

• Experience with programmable data planes, SRv6, BGP/ECMP, anycast, and multi-cluster traffic routing.

• Background in security for networking stacks: firewalling, ACLs, mTLS, DDoS detection/mitigation, bot defense.

• Experience building self-service traffic platforms and developer-facing APIs/SDKs.

• Knowledge of hardware acceleration: SmartNICs, ASICs, FPGA-based offload, and NIC telemetry.

• Experience with time synchronization and precision timing (PTP), clocking, and its impact on networking performance.

#LI-Hybrid

This job posting relates to an existing vacancy within eBay.

eBay is an equal opportunity employer. All qualified applicants will receive consideration for employment without regard to race, color, religion, national origin, sex, sexual orientation, gender identity, and disability, or other legally protected status. If you have a need that requires accommodation, please contact us at . We will make every effort to respond to your request for accommodation as soon as possible. View our to learn more about eBay's commitment to ensuring digital accessibility.

Please see the for information regarding how eBay handles your personal data collected when you use the eBay Careers website or apply for a job with eBay. The eBay Careers website uses cookies to enhance your experience. By continuing to browse the site, you agree to our use of cookies. Visit our for more information.