Staff Software Engineer - Linux Kernel

LinuxCareers; New York, Northern (NY, KY); Hybrid; USD 211,000 - 254,000; Full time

Job summary

Fastly's Kernel and Host Networking team builds and operates the Linux kernel running across their global edge network. As a Staff Software Engineer, you will own technical problems end-to-end—from kernel crashes and hardware enablement through design, implementation, and fleet rollout.

You will set technical direction, develop drivers for new servers and NICs, improve datapath with XDP/eBPF, and own production health across the fleet.

Qualifications

• 7+ years of related engineering experience with 3+ years leading projects.
• Production Linux kernel development experience; debug use-after-free, refcount and leak bugs with KASAN, kdump, ftrace, perf or bpftrace.
• Working knowledge of the Linux scheduler and memory management (EEVDF, memcg).
• Experience managing a kernel patch stack and collaborating with upstream communities.
• Solid understanding of the Linux network stack (TCP/IP, sk_buff lifecycle, qdiscs, NIC drivers) and XDP or eBPF with deep expertise in at least one area.

Responsibilities

• Set technical direction for kernel projects and mentor engineers; own projects end-to-end from problem statement through fleet rollout.
• Bring new servers, CPUs and NICs from first boot to full fleet deployment: develop drivers, configure IRQ affinity, RSS and queue layout on high core count hosts.
• Improve datapath and transport performance using XDP, eBPF and IETF-specified protocols; debug cross-layer issues with application teams.
• Develop and maintain kernel changes and Fastly kernel modules on long-term kernel branches; reduce private delta by upstreaming contributions.
• Own kernel production health: triage crashes, WARNs and regressions across the fleet, identify root causes and ship fixes; lead on-call rotation and incident response.

Skills

C Programming

Kernel Development

Leadership

Linux Networking

XDP / eBPF

System Debugging

Performance Tuning

Tools

KASAN

kdump

ftrace

perf

bpftrace

Upstream

Job description

Fastly's Kernel and Host Networking team builds and operates the Linux kernel running across their global edge network. As a Staff Software Engineer, you will own technical problems end-to-end—from kernel crashes and hardware enablement through design, implementation, and fleet rollout—spanning networking, XDP, eBPF, memory, performance, and distributed systems consistency.

What You'll Do

• Set technical direction for kernel projects and mentor engineers; own projects end-to-end from problem statement through fleet rollout
• Bring new servers, CPUs and NICs from first boot to full fleet deployment: develop drivers, configure IRQ affinity, RSS and queue layout on high core count hosts
• Improve datapath and transport performance using XDP, eBPF and IETF-specified protocols; debug cross-layer issues with application teams
• Develop and maintain kernel changes and Fastly kernel modules on long-term kernel branches; reduce private delta by upstreaming contributions
• Own kernel production health: triage crashes, WARNs and regressions across the fleet, identify root causes and ship fixes; lead on-call rotation and incident response

What You Need

• 7+ years of related engineering experience including substantial production C, with 3+ years leading technical projects
• Production Linux kernel development experience, including debugging use-after-free, refcount and leak bugs with KASAN, kdump, ftrace, perf or bpftrace
• Working knowledge of the Linux scheduler and memory management (EEVDF, memcg)
• Experience managing a kernel patch stack and collaborating with upstream communities
• Solid understanding of the Linux network stack (TCP/IP, sk_buff lifecycle, qdiscs, NIC drivers) and XDP or eBPF with deep expertise in at least one area

Nice to Have

• Upstream kernel contributions or subsystem maintainership
• Deep knowledge of transport protocols from IETF RFCs: QUIC, TCP, ECN, L4S, MASQUE
• Hardware enablement on AMD EPYC or Intel platforms and NIC driver experience (mlx5, ice, i40e)
• Experience with load balancing, traffic steering systems, CDN or large edge network environments; container networking with network namespaces, veth, cgroups and eBPF-based CNI datapaths

$211,370–$253,644 per year; equity and discretionary bonus programs; comprehensive benefits including medical, dental, vision; family planning, mental health support, life/disability/accident insurance; 401(k) with company match, ESPP, flexible vacation, 18 days accrued paid sick leave, 11 paid holidays, 12 paid wellness days