About Spectrum
Spectrum is Cloudflare's Layer 4 reverse proxy — the front door for arbitrary TCP and UDP traffic. It gives customers Cloudflare'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 Cloudflare colo, terminating and forwarding a very large volume of concurrent connections per second, and its control plane manages configuration, provisioning, and integration with adjacent Cloudflare 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 Cloudflare'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.
Some of the things you'll work on:
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
You'll partner closely with the rest of Packet Processing, other Traffic Management teams, DDoS, DNS, Core SRE, and Edge SRE to solve problems that span the entire Cloudflare 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
Compensation
Compensation may be adjusted depending on work location.
Equity
This role is eligible to participate in Cloudflare’s equity plan.
Benefits
Cloudflare offers a complete package of benefits and programs to support you and your family. Our benefits programs can help you pay health care expenses, support caregiving, build capital for the future and make life a little easier and fun! The below is a description of our benefits for employees in the United States, and benefits may vary for employees based outside the U.S.
Health & Welfare Benefits
Medical/Rx Insurance
Dental Insurance
Vision Insurance
Flexible Spending Accounts
Commuter Spending Accounts
Fertility & Family Forming Benefits
On-demand mental health support and Employee Assistance Program
Global Travel Medical Insurance
Financial Benefits
Short and Long Term Disability Insurance
Life & Accident Insurance
401(k) Retirement Savings Plan
Employee Stock Participation Plan
Time Off
Flexible paid time off covering vacation and sick leave
Leave programs, including parental, pregnancy health, medical, and bereavement leave
What Makes Cloudflare 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 Cloudflare’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. Since the project, we've provided services to more than 425 local government election websites in 33 states.
1.1.1.1 : We released 1.1.1.1 to help fix the foundation of the Internet by building a faster, more secure and privacy-centric public DNS resolver. This is available publicly for everyone to use - it is the first consumer-focused service Cloudflare has ever released. Here’s the deal - we don’t store client IP addresses never, ever. We will continue to abide by our privacy commitment and ensure that no user data is sold to advertisers or used to target consumers.
Sound like something you’d like to be a part of? We’d love to hear from you!
Please note that applicants who progress to the offer stage of the interview process may be asked to attend an in-person interview within one of the Cloudflare Offices or Cloudflare Hubs. More details about this will be available at that stage of the interview process.
This position may require access to information protected under U.S. export control laws, including the U.S. Export Administration Regulations. Please note that any offer of employment may be conditioned on your authorization to receive software or technology controlled under these U.S. export laws without sponsorship for an export license.
Cloudflare is proud to be an equal opportunity employer. We are committed to providing equal employment opportunity for all people and place great value in both diversity and inclusiveness. All qualified applicants will be considered for employment without regard to their, or any other person's, perceived or actual race, color, religion, sex, gender, gender identity, gender expression, sexual orientation, national origin, ancestry, citizenship, age, physical or mental disability, medical condition, family care status, or any other basis protected by law. We are an AA/Veterans/Disabled Employer.
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