Systems Engineer, Spectrum

United States Digital Space LLC; United States; Hybrid; USD 150,000 - 190,000; Full time

Job summary

United States Digital Space LLC is hiring for a Systems Engineer to own the Spectrum edge dataplane and related control-plane components. You will work on a high-scale L4 proxy powering the company’s global network, focusing on performance, reliability, and production-readiness.

The role emphasizes Go development, exposure to Rust, and deep knowledge of L3/L4 networking. You will collaborate across teams to integrate with Unimog, Magic Transit, and Argo Smart Routing, ensuring robust operations.

Qualifications

• Experience building large-scale, reliable, distributed systems.
• Strong programming experience in Go; familiarity with Rust is a plus.
• Solid understanding of L3/L4 networking: TCP, UDP, IP, NAT, anycast, and packet flows.
• Experience with Linux networking primitives — sockets, eBPF, netfilter/nftables, tc.
• Experience designing and integrating RESTful APIs and backend systems.
• Comfort with operating what you build in production — on-call, incident response, root-cause analysis.

Responsibilities

• Own Spectrum edge dataplane development in Go: connection acceptance, TLS termination, PROXY protocol, and traffic shaping.
• Own Spectrum control plane development in Go: configuration APIs and global config push.
• Integrate Spectrum with Unimog, Magic Transit, Argo Smart Routing, and other dataplane components.
• Drive operational excellence: analytics, observability, incidents, and debt reduction.
• Help evolve the Spectrum roadmap as the L4 counterpart to the HTTP proxy stack.

Skills

Go programming

Distributed systems

Networking knowledge

C/Go-style high performance

Tools

Go

Rust

eBPF

Linux networking

Job description

About Us

At the company, we are on a mission to help build a better Internet. Today the company runs one of the world’s largest networks that powers millions of websites and other Internet properties for customers ranging from individual bloggers to SMBs to Fortune 500 companies. the company protects and accelerates any Internet application online without adding hardware, installing software, or changing a line of code. Internet properties powered by the company all have web traffic routed through its intelligent global network, which gets smarter with every request. As a result, they see significant improvement in performance and a decrease in spam and other attacks. the company was named to Entrepreneur Magazine’s Top Company Cultures list and ranked among the World’s Most Innovative Companies by Fast Company.

At the company, we’re not looking for people who wait for a polished roadmap; we’re looking for the builders who see the cracks in the Internet that everyone else has simply learned to live with. We value candidates who have the instinct to spot a \"normalized\" problem and the AI-native curiosity to create a solution using the latest tools. Our culture is built on iteration, leveraging AI to ship faster today to make it better tomorrow, while ensuring that every improvement, no matter how small, is shared across the team to lift everyone up. If you’re the type of person who values curiosity over bureaucracy, and that AI is a partner in solving tough problems to keep the Internet moving forward, you’ll fit right in.

Available Locations: Austin, TX

About the team

the company'sPacket Processing team builds and operates the L3/L4 dataplane services that sit at the front door of our global network. We own the systems that receive, inspect, route, and forward every packet entering the company — from DDoS-scrubbed IP transit to TCP/UDP application traffic — across every colo in the world. Our work spans Unimog (the company's L4 load balancer that steers traffic to the right machine in every datacenter), Magic Transit and the company WAN (our IP-layer DDoS protection and private connectivity products), and Spectrum (our L4 reverse proxy for arbitrary TCP and UDP applications). Together, these systems form the packet-processing foundation of the Traffic Management organization.

We are a team of engineers who obsess over performance, correctness, and reliability at massive scale. We work close to the metal, we own what we build in production, and we take pride in shipping systems that \"just work\" for a very large fraction of the internet.

About Spectrum

Spectrum is the company's Layer 4 reverse proxy — the front door for arbitrary TCP and UDP traffic. It gives customers the company's DDoS mitigation, anycast performance, TLS termination, and global footprint for any TCP or UDP application: gaming servers, SSH, MQTT, custom protocols, and TLS-terminated services of every shape. Spectrum's edge dataplane runs across every the company colo, terminating and forwarding a very large volume of concurrent connections per second, and its control plane manages configuration, provisioning, and integration with adjacent the company systems.

About the role

As a member of Spectrum in the Packet Processing team, we're looking for a Systems Engineer who wants to take shared ownership of a critical, high-scale L4 proxy and help evolve it into the next generation of the company's non-HTTP traffic platform. This is a rare opportunity to work on a product with massive existing scale while helping shape where it goes next as a first-class part of our L3/L4 dataplane story.

Responsibilities

• The Spectrum edge dataplane (Go): TCP/UDP connection acceptance and forwarding, TLS termination, PROXY protocol, connection accounting, and eBPF integrations


• The Spectrum control plane (Go): application configuration APIs, provisioning, and the systems that push config globally to every edge machine


• Cross-dataplane integrations: how Spectrum fits together with Unimog for L4 load balancing, with Magic Transit for IP transit, with Argo Smart Routing for accelerated origin paths, etc


• Operational excellence: analytics pipelines, observability, on‑call, incident response, and paying down technical debt in a product with a long production history


• Roadmap evolution: help shape where Spectrum goes next as the L4 counterpart to our HTTP proxy stack

Desirable Skills, Knowledge, and Experience:

• Experience building and shipping large-scale, reliable, highly distributed systems


• Strong programming experience in Go; familiarity with or willingness to work in Rust is a plus


• Solid understanding of L3 and L4 networking: TCP, UDP, IP, connection state, NAT, anycast, and packet flows


• Experience with Linux networking primitives — sockets, eBPF, network namespaces, netfilter/nftables, tc


• Experience designing and integrating RESTful APIs and backend systems


• Comfort with operating what you build in production — on‑call rotations, incident response, and root‑cause analysis


• Ability to reason about existing systems at scale: reading unfamiliar code, understanding hidden dependencies, and safely evolving software that has been in production for years


• Excellent debugging and optimization skills, particularly around performance and connection lifecycle issues


• Focus on clarity in written and verbal communication; ability to work across teams to land shared solutions

Bonus Points

• Experience with TLS termination, PROXY protocol, or L4/L7 proxies (Envoy, HAProxy, nginx stream, etc.)


• Experience with ClickHouse, Kafka, or large-scale connection/flow analytics pipelines


• Experience with globally‑distributed KV or config‑push systems


• Prior work on DDoS mitigation, anycast routing, L4 load balancing, or high‑throughput edge network daemons


• Contributions to open‑source networking or proxy projects

What Makes the company Special?

We’re not just a highly ambitious, large-scale technology company. We’re a highly ambitious, large-scale technology company with a soul. Fundamental to our mission to help build a better Internet is protecting the free and open Internet.

Project Galileo: Since 2014, we've equipped more than 2,400 journalism and civil society organizations in 111 countries with powerful tools to defend themselves against attacks that would otherwise censor their work, technology already used by the company’s enterprise customers--at no cost.

Athenian Project: In 2017, we created the Athenian Project to ensure that state and local governments have the highest level of protection and reliability for free, so that their constituents have access to election information and voter registration. S