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! 

Location(s) Available: Portugal

About the department

Cloudflare’s Research Team is involved with building the future of Cloudflare by tackling strategic projects that have a large impact on Cloudflare systems and the Internet at large. Our focus is on solving difficult problems that serve our goal of connecting and protecting users, applications, and data, while always making the Internet better.

In our quest to make the Internet better, we frequently find ourselves exploring open problems at the boundaries of current work in scalable security, privacy, and systems, including AI/ML and performance.  We make cutting edge research contributions in-house, as well as in collaboration with academia, Internet standards organizations like the IETF, and more!

Our team includes experts in areas including cryptography, privacy, measurement, cache optimization, and time series analysis.  We seek interns that augment our existing expertise as well as those who are working in broadly related areas.  We are researchers at heart, and we love learning!  While we have a range of potential intern projects prepared, we’re particularly interested in candidates who have found a piece of Cloudflare they would like to improve, and have an idea of what they would like to do. 

More information about Cloudflare's approach to research can be found here.

What you'll do

Cloudflare's Research Team solves difficult problems in security, performance, and privacy at scale. This involves systems engineering, open source software development, protocol design, implementation of primitives, with lots of measurement alongside. We make cutting edge research contributions in-house, as well as in collaboration with academia, Internet standards organizations like the IETF, and more!

Successful candidates will be matched to suitable projects. We also welcome novel proposals and ideas that can help to inform or build a better Internet (in the form of a max 200 word proposal).

Research Program Areas

Cloudflare Research has six current program areas. Candidates whose interest or expertise lie outside one of these areas are also encouraged to apply, particularly if they have a particular, specific interest in an aspect of Cloudflare’s technical stack or operations.

Applied AI/ML 

Machine learning and statistical automation is a valuable toolkit for research across Cloudflare’s products and services.  The AI/ML research team seeks to answers cutting edge questions at the intersection of machine learning and scalable system design to answer questions about fraud, predictive optimization, and distributed learning. 

Internet Infrastructure and Governance

Cloudflare Research is dedicated to the health of the broader Internet, including significant work with standards bodies (IETF, W3C, NIST, e.g.) and open implementations.  This program explores ways to improve the underlying infrastructure of the Internet and promote its fair and equitable governance.  This umbrella also includes decentralized web technologies and protocols such as IPFS and Web3.  Example project areas include Internet routing security and resilience (e.g., RPKI, BGP), DNS and domain name security improvements, and addressing the global digital divide.

Measurement and Performance Optimization

A key driver of research questions and outcomes is observability into system behavior. This program area focuses on researching and developing novel techniques to measure and improve the performance and reliability of websites, applications, and services hosted on Cloudflare infrastructure.  Example project areas include cache and CDN optimization, time series and ML/AI based performance analysis, edge computing and serverless applications, and network congestion control and latency reduction techniques.

Privacy and Data Protection

This program is about reducing or eliminating personal data at all layers of the stack, as well as metadata on the broader Internet, to ensure the protection of user data and maintain compliance with global data protection regulations. This work includes efforts to upgrade protocols to enable better data privacy (e.g. hostnames -- via SNI, IP addresses, or fingerprintable data) as well as cryptographic techniques such as secret splitting to limit the potential for compromising private data.  Example projects include cryptographic Attestation of Personhood, privacy-preserving analytics, website fingerprinting protection, and connection coalescing.

Security and Resilience

​​The Internet is continually evolving, and dangers to the Internet evolve with it.  This program is dedicated to researching and developing innovative solutions to protect Cloudflare's infrastructure and its customers, as well as the Internet at large, from various cyber threats.  Efforts in this area frequently include close collaboration with teams across Cloudflare, such as a recent push to deploy post-quantum security throughout Cloudflare’s internal network.  Example project areas include DDoS attack mitigation and prevention, bot and automated threat detection, secure DNS, and zero-trust architectures and access control.  

Systems and Formal Methods

Formal methods are a powerful toolkit for answering the types of questions around privacy, security, and correctness that are core to Cloudflare’s operations.  The Systems and Formal Methods group is the home for questions about system architecture and correctness that fall outside the realm of pure networking or privacy research. Sample projects include kernel-level cryptography implementations, cache design and observability, and logging and analysis.

General Intern Requirements

  • Interest in solving open-ended problems.
  • Proven track record of peer-reviewed research, open-source software contributions, or standards development
    • Some level of research maturity is expected, but students at every level are welcome to apply
  • Evidence of ability to work in multiple languages -- Go, Rust and Javascript are particularly desirable.
  • Experience (and love) for debugging to ensure the system works in all cases.
  • Experience with a continuous integration workflow, and use of source control (we use git)
  • Strong systems level programming skills.
  • Willing and eager to share knowledge, with the skills to do so.

Additional Requirements

Knowledge or experience with at least one of the following:

  • Computer networking protocols (TCP/IP, DNS, BGP, QUIC, etc.) and related algorithms
  • Machine learning analysis for systems or network optimization
  • Authentication protocols, applied cryptography, PKI and SSL/TLS
  • Operating or distributed systems analysis or development
  • Applied cryptography and cryptographic protocols
  • Measurement for network and computer systems

 Bonus Points:

  • Proven track record of independently driving projects in a fast-paced environment
  • Experience with high throughput/low latency real-time systems and/or content delivery networks

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: We equip politically and artistically important organizations and journalists 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: We created 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.

Path Forward Partnership: Since 2016, we have partnered with Path Forward, a nonprofit organization, to create 16-week positions for mid-career professionals who want to get back to the workplace after taking time off to care for a child, parent, or loved one. We released 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 hr@cloudflare.com or via mail at 101 Townsend St. San Francisco, CA 94107.

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