Software Engineer, Network Firewall

At Cloudflare, 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., As a Software Engineer on our team, you will work across a wide range of technologies and systems to deliver new features, improve performance, and increase the scalability of our Network Services products. You will help evolve our Network Firewall and related security capabilities across both north-south and east-west network architectures, with demanding throughput and latency requirements. You’ll build, deploy, and operate your team’s systems on top of one of the largest edge networks in the world. You’ll partner with some of the best engineers and product managers to solve big problems that have a meaningful impact in the lives of our customers and users.

• Experience building and shipping large-scale, reliable, highly distributed systems
• Systems-level programming experience; experience with Go and/or Rust is valuable
• Expertise in L3 and L4 networking protocols; L2 experience is also valuable
• Experience building high-performance network security products such as network firewalls, IDS/IPS, DDoS mitigation, rate limiting, packet capture, or threat intelligence integrations
• Experience with low-latency userspace packet processing; familiarity with Linux kernel networking primitives such as netfilter, nftables, eBPF, tc, and network namespaces is also valuable
• Experience designing and integrating RESTful APIs and backend systems
• Experience with large-scale distributed data pipelines, from data structuring to efficient querying to data analysis
• Excellent debugging, profiling, and performance optimization skills for high-throughput, latency-sensitive systems

Bonus Points

• Attention to detail and ability to solve complex customer problems
• Own solutions end-to-end and driving the design, development, and deployment process
• Able to work across teams and level common, sustainable solutions
• Creative, open-minded, collaborative problem solver
• Focus on clarity in written and verbal communication

At Cloudflare, 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. Cloudflare protects and accelerates any Internet application online without adding hardware, installing software, or changing a line of code. Internet properties powered by Cloudflare 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. Cloudflare was named to Entrepreneur Magazine’s Top Company Cultures list and ranked among the World’s Most Innovative Companies by Fast Company., 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.