Senior Software Engineer, Network Simulations

SimSpace is an AI Proving Ground that enables organizations to train, test, and outmaneuver adversaries in various environments. They are seeking a Senior Software Engineer to serve as the technical lead for their internet simulation platform, responsible for designing and building a kernel-level simulation layer that accurately reproduces internet routing behavior. The role involves architectural direction, mentoring engineers, and collaborating with other teams to develop a multi-tenant service for cyber range deployments.

Responsibilities:

• Own the end-to-end architecture of the eBPF-based routing simulation layer, including XDP and TC hook point design, BPF map structure, and synthetic ICMP TTL-exceeded generation that makes traceroute and MTR behave correctly against the simulated topology
• Design and build the control-plane topology database and the pipeline that compiles real-world internet topology data into a form that in-range agents can consume and apply
• Architect the in-range proxy agent: the lightweight component that bridges the persistent control plane to individual cyber ranges, applying topology configuration locally and handling DNS delegation and traffic forwarding
• Define the interface contract between the control plane and in-range agents, including topology update propagation, graceful degradation when control plane connectivity is interrupted, and agent lifecycle management
• Serve as technical lead for the team — making daily architectural decisions across the full service scope, conducting design reviews, and maintaining engineering quality across all four engineering roles on the team
• Partner with other Engineers on novel simulation challenges, bring independent judgment to architectural tradeoffs, and shape the technical roadmap
• Mentor engineers on the team, raising the bar on systems design, kernel-level debugging, and engineering rigor
• Collaborate with adjacent platform teams on the operational model for a long-lived, multi-tenant service serving active cyber range deployments

Requirements:

• Deep expertise in Linux kernel networking and eBPF program development, including XDP, TC hooks, BPF map types, and the tradeoffs involved in kernel-space packet processing
• Strong systems programming skills — C or Rust for eBPF program development, and Go or Python for the control-plane agent and tooling layer
• Solid understanding of real-world internet routing — BGP, ASN topology, CIDR allocation, inter-AS peering — sufficient to model it faithfully without running routing software
• Experience designing systems with well-defined control plane and data plane separation, particularly where distributed components may have intermittent connectivity to a central controller
• Demonstrated technical leadership: you have set architectural direction and driven engineering quality across a team, whether as a tech lead, principal, or senior-plus individual contributor
• Comfort at the intersection of research and production engineering — this role involves taking a proof of concept and building it into something that runs reliably at scale
• Familiarity with Kubernetes as the deployment environment for both control plane services and distributed agent components
• Experience with network simulation, traffic shaping, or cyber range infrastructure is a strong plus
• Prior work in cybersecurity, defense, or government-adjacent environments is a plus due to SimSpace's customer base