Senior Engineer, Cilium Cni & Cloud Networking

Weights & Biases Weights & Biases · Data AI · Bellevue, WA +4 · Technology

Senior Engineer role focused on designing, building, and operating the container networking layer (Cilium CNI) for CoreWeave's Kubernetes platforms, supporting large-scale GPU clusters with demanding throughput and latency requirements. Requires strong experience in cloud networking, eBPF, Kubernetes, and systems programming.

What you'd actually do

  1. design, build, and operate the container networking layer that underpins CoreWeave’s Kubernetes platforms
  2. work on evolving our CNI stack to support large, high-density GPU clusters with demanding throughput and latency requirements
  3. partner closely with Kubernetes, Infrastructure, and Network Services engineers to ensure the platform is highly available, observable, and secure
  4. help shape how our networking platform scales for future growth

Skills

Required

  • Software Engineering
  • Systems Engineering
  • cloud infrastructure
  • large-scale distributed systems
  • Cilium CNI
  • Kubernetes
  • eBPF
  • cloud networking
  • VPCs
  • subnets
  • routing
  • security groups/ACLs
  • NAT
  • ingress/egress architectures
  • multi-tenant network architectures
  • TCP/IP
  • dynamic routing
  • BGP
  • ECMP
  • MTU/fragmentation
  • overlay/underlay networking
  • VXLAN
  • Geneve
  • encapsulation
  • network observability
  • troubleshooting L3-L7
  • Golang
  • C/C++
  • CI/CD
  • Kubernetes at scale

Nice to have

  • cloud-scale network services
  • tens of thousands of nodes
  • multiple regions
  • Cilium contributions
  • Kubernetes contributions
  • open-source networking projects
  • eBPF development
  • performance tuning
  • Kubernetes operators
  • controllers
  • service meshes
  • multi-cluster networking
  • cluster mesh solutions
  • GPU-heavy environments
  • HPC environments
  • performance-sensitive environments

What the JD emphasized

  • Hands-on production experience with Cilium CNI (or equivalent advanced CNIs)
  • Strong understanding of Cilium’s eBPF datapath, policy model, and load-balancing mechanisms
  • Deep knowledge of cloud networking concepts
  • Experience designing multi-tenant network architectures with strong isolation and security
  • Solid grounding in TCP/IP, dynamic routing (e.g., BGP), ECMP, MTU/fragmentation, and overlay/underlay networking (VXLAN, Geneve, encapsulation)
  • Experience with network observability and troubleshooting across L3–L7
  • Proficiency in at least one systems language such as Golang or C/C++
  • Experience operating Kubernetes at scale