Staff Software Engineer - Linux Kernel
Denver · New York City, NY · San Francisco · USD 211,370-253,644 · 7+ years experience · Hybrid · Posted Oct 6, 2026
At a glance
- Experience
- 7+ years experience
- Workplace
- Hybrid
- Location
- Denver · New York City, NY · San Francisco
- Salary
- USD 211,370-253,644
About the role
- Fastly's Kernel and Host Networking team builds and ships the Linux kernel that runs on every server in the global edge network, and every customer request passes through it.
- As a Staff engineer you own technical problems end to end: from a crash signature or a new NIC on the bench, through root cause and design, to a change that is upstreamed and safely running on thousands of servers.
Responsibilities
- Set technical direction for kernel projects, own them end to end from problem statement to fleet rollout, and mentor engineers on the team
- Take new servers, CPUs and NICs from first boot to full fleet: drivers, IRQ affinity, RSS and queue layout on high core count hosts
- Improve datapath and transport performance with XDP, eBPF and protocol work based on IETF specifications
- Debug problems that cross layers with application teams, such as MTU behavior, cgroup memory accounting and packet filtering
- Develop and maintain kernel changes and Fastly kernel modules on our long term kernel line, and reduce our private delta by upstreaming
- Make sure state pushed from control planes to eBPF and XDP programs is applied, verified and safe to roll back
- Own kernel health in production: triage crashes, WARNs and regressions across the fleet, find the root cause and ship the fix
- Own and improve the kernel release process and the signals behind it: CI, bake, canary, staged rollout and rollback across thousands of servers, plus crash metrics and drift detection that fire before customers notice
- Join the on-call rotation, lead the kernel side of incidents and drive follow-up actions to closure
Requirements
- 7+ years of related engineering experience, including substantial production C, with 3 of those years leading technical projects
- Production Linux kernel development, including debugging use-after-free, refcount and leak bugs with KASAN, kdump, ftrace, perf or bpftrace
- Working knowledge of the scheduler and memory management (EEVDF, memcg)
- Experience managing a kernel patch stack and working 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 of these areas
- Operational discipline: staged rollouts, canaries, kill switches, observability, postmortems and closing action items
- Understanding of distributed systems: control plane and datapath consistency, partial failure and safe config rollout at fleet scale
- Ability to design broadly scoped work and drive it across teams
Preferred qualifications
- Upstream kernel contributions or subsystem maintainership
- Deep Knowledge of Transport protocols from IETF RFCs: QUIC, TCP, ECN and L4S, MASQUE
- Hardware enablement on AMD EPYC or Intel platforms, and NIC drivers such as mlx5, ice or i40e
- Load balancing or traffic steering systems
- CDN or large edge network environments
- Container networking: network namespaces, veth, cgroups, and eBPF-based CNI datapaths
Benefits
- Medical, dental, and vision insurance
- Family planning
- Mental health support along with Employee Assistance Program
- Insurance (Life, Disability, and Accident)
- Flexible Vacation policy
- Up to 18 days of accrued paid sick leave
- 401(k) (including company match)
- Employee Stock Purchase Program
- 11 paid local holidays
- 12 paid company wellness days
Workplace
- This position is open to remote and hybrid work locations in the United States.
- This position may require travel as required by your role or requested by your manager.
Skills
- C
- Linux Kernel
- KASAN
- Kdump
- Ftrace
- Perf
- Bpftrace
- XDP
- eBPF
- TCP/IP
- QUIC
- ECN
Show all 15 skills
- L4S
- MASQUE
- Mlx5