Software Engineer, Traffic (Lisbon / London)

About Us

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.

We realize people do not fit into neat boxes. We are looking for curious and empathetic individuals who are committed to developing themselves and learning new skills, and we are ready to help you do that. We cannot complete our mission without building a diverse and inclusive team. We hire the best people based on an evaluation of their potential and support them throughout their time at Cloudflare. Come join us!

Role Summary

The mission of the Traffic team is to build software systems that improve the performance and reliability of Cloudflare's network. The scope of our work is significant and has a broad impact across our portfolio of products.

One such system is a control plane service that ingests a diverse set of data in order to load-balance customer traffic through directly instructing our network infrastructure.

Role Responsibilities

As a member of the Traffic team you will build and extend various traffic management and supporting systems. You will work closely with Network Engineering, Product Engineering, Network Strategy, and other teams to translate their requirements into new capabilities on our platform.

You will participate in all stages of the software development lifecycle: from designing and documenting systems, to writing code and automated tests, to planning, managing, and monitoring production software deployments. You will work with a wide range of technologies and programming languages, including Go, Python, Rust, ClickHouse, Salt, PostgreSQL, Grafana, Kubernetes, NETCONF, and more.

Our team at Cloudflare operates under a "Run What You Build" model. This means we are responsible for the health of our systems and actively participate in our team's on-call rotation as part of our operational duties.

Because you'll be solving problems of massive scale and significance, and shaping the future of reliability and performance on the Internet, you are a growth-oriented individual who enjoys being outside of your comfort zone. You are comfortable in a fast-paced but sensible work environment. You value curiosity and empathy and lead with these values.

Role Requirements

Must-Have Skills

• Systems-level programming experience in Go, Python, Rust, C, or C++
• A solid grasp of networking protocols in Layers 3 and 4 of the OSI Model.
• Knowledge of HTTP, TLS, and CDN networks.
• Experience in implementing, deploying, and debugging secure and highly-available distributed systems.
• Strong collaboration and communication skills.
• Experience/interest in network performance monitoring and tuning

Bonus Points

• Knowledge of TCP/IP and Internet routing.
• Knowledge of statistical-analysis techniques and control theory.
• Experience building tools and APIs.
• Experience with monitoring, alerting, and debugging large-scale distributed systems
• Experience participating in an on-call rotation.

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!

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.

Cloudflare provides reasonable accommodations to qualified individuals with disabilities. Please tell us if you require a reasonable accommodation to apply for a job. Examples of reasonable accommodations include, but are not limited to, changing the application process, providing documents in an alternate format, using a sign language interpreter, or using specialized equipment. If you require a reasonable accommodation to apply for a job, please contact us via e-mail at or via mail at 101 Townsend St. San Francisco, CA 94107.