Senior/Staff Software Engineer, Network Infrastructure

About This Role

You will build the public and private network infrastructure connecting all of fal's data centers and cloud environments, supporting both our public serverless platform and custom compute clusters. The scope includes internet routing, private connectivity, overlay networks, DNS, IP address management, cloud-provider integration, and high-performance Linux networking.

You will work across the networking stack - from BGP announcements and private peering to kernel-level performance tuning. The goal is to make our network fast, reliable, secure, isolated, and easy to operate.

What you'll do

• Design, build, validate, and operate public and private networks across the public platform and private compute clusters
• Use AI aggressively to automate and accelerate network provisioning, configuration, validation, monitoring, and recovery
• Manage ASNs, public IP prefixes, and private address space (allocation, registration, announcement, lifecycle)
• Build and operate BGP routing: route policies, communities, filtering, traffic engineering, and failover
• Announce customer and company IP ranges from physical infrastructure and cloud providers, including BYOIP integrations
• Establish private peering with customers, partners, data centers, internet exchanges, and cloud providers
• Build private and overlay networks using VXLAN, IPsec, WireGuard, and Tailscale
• Operate DNS networking patterns including anycast DNS and mDNS
• Tune the Linux networking stack for high throughput, low latency, and large connection counts
• Build network observability and diagnostics using metrics, logs, flow data, active probes, and packet captures
• Develop reusable tooling, standards, documentation, and runbooks
• Collaborate with customers and internal teams to translate connectivity, security, isolation, and performance requirements into sound network designs

Qualifications/Nice to Have

• 5+ years building and operating production network infrastructure
• Strong Linux networking: routing tables, policy routing, network namespaces, bonding, VLANs, bridges, firewalling, NAT, conntrack
• Deep BGP knowledge: route selection, communities, filtering, convergence, multipath, troubleshooting
• Experience managing ASNs, public IP space, BGP announcements, IPAM, RPKI/ROAs, IRR records
• Experience designing private IPv4/IPv6 address plans and preventing cross-customer/region conflicts
• Production VXLAN overlay network experience
• Production IPsec, WireGuard, or Tailscale experience
• Experience with anycast DNS and mDNS
• Experience with private peering and cloud provider interconnects
• Linux networking performance tuning: congestion control, queue disciplines, socket buffers, MTU, NIC offloads, RSS/RPS/XPS, IRQ affinity
• Packet-level troubleshooting: iproute2, tc, ethtool, tcpdump, Wireshark, mtr
• Ansible or equivalent network configuration automation
• EVPN as a VXLAN control plane
• FRRouting, BIRD, or similar software-routing platforms
• AWS Direct Connect, Google Cloud Interconnect, Azure ExpressRoute
• Internet exchanges, cross-connects, route servers, colocation networking
• DDoS detection, mitigation, scrubbing, BGP-based traffic diversion
• eBPF, XDP, DPDK
• NetBox, Nautobot, Nornir
• Authoritative or recursive DNS infrastructure at scale
• Network hardware: Arista, Juniper, Cisco
• Kubernetes networking, service load balancing, CNI
• Python or Go

What We Offer at fal

• Interesting and challenging work
• A lot of learning and growth opportunities
• We offer visa sponsorship and will help you relocate to San Francisco.
• Health, dental, and vision insurance (US)
• Regular team events and offsites

Compensation

• $180,000 - $250,000 + equity + comprehensive benefits package