About Us

At Cloudflare, we have our eyes set on an ambitious goal: to help build a better Internet. Today, Cloudflare runs one of the world’s largest distributed networks that powers more than 1.5 trillion page views each month across 5 million Internet properties. More than 10 percent of all global Internet requests flow through Cloudflare’s network. Cloudflare protects and accelerates any Internet application online without adding hardware, installing software, or changing a line of code.

Our customers range from Fortune 500 companies and non-profits to small businesses and budding entrepreneurs. Every day, about tens of thousands of new customers sign up. We’re working to create a faster, more secure, and more reliable experience for anyone online and given the scale at which we operate, our mission is big. Our team is hard at work shaping the future of the Internet by solving some of its toughest challenges. Come join us.

About the Department

Cloudflare’s CTO office is involved with building the future of Cloudflare by tackling strategic projects that have a large impact on the way Cloudflare systems, and the Internet at large, work. Engineers in the CTO office are expected to research new ideas and technologies, dive into existing codebases to make meaningful changes, work independently on greenfield projects, and collaborate closely with the Engineering organization to achieve common goals.

The Cryptography team is focused on solving difficult problems in security, performance, and privacy at scale using cryptographic tools. This involves systems engineering, open source software development, protocol design, the implementation of cryptographic primitives, contributions to cutting-edge research in collaboration with academia, participation in Internet standards organizations like the IETF, and more.

We are looking for a seasoned systems engineer and programmer with a broad background and a specialization in cryptography to work on our team.

Candidates will have extensive experience in implementing real-world cryptographic protocols such as TLS. Substantial contributions to cryptographic software such as OpenSSL are preferred. Experience in Go and C are required, experience with x86/amd64 assembly is preferred. Cryptography Engineers are expected to have deep domain knowledge, be familiar with the nuances of implementing public-key cryptography (PKI), side-channel attacks, padding oracles, constant-time implementations. Candidates must also be familiar with Web protocols and distributed systems.


  • B.S. or M.S. Computer Science or related field, or equivalent experience
  • Experience shipping production-quality code in a fast-paced, web-scale environment
  • Advance knowledge of networking protocols - TCP/IP, DNS, BGP, QUIC etc.
  • In-depth knowledge of authentication protocols, applied cryptography, PKI and SSL/TLS
  • Proficiency in the following languages - Go and C.
  • Knowledge of the latest attack trends, tools and the threat landscape
  • Proven track record of independently driving projects in a fast-paced environment
  • Excellent communication skills on both technical and non-technical issues

Bonus Points:

  • Substantial contributions to cryptography software such as OpenSSL or Go's crypto/tls
  • Experience with high throughput/low latency real-time systems and/or content delivery networks 
  • Assembly language proficiency (x86/amd64)

What Makes Us 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. In 2014, we launched Project Galileo, an initiative through which we partner with global NGOs to identify websites at risk of attack and provide the same state-of-the-art mitigation technology already used by Cloudflare’s enterprise customers--at no cost. Project Galileo equips politically and artistically important organizations and journalists with powerful tools to defend themselves against attacks that would otherwise censor their work.

Additionally, in 2016, we announced our partnership with Path Forward, a nonprofit organization that works with companies to create 18-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. With the lofty goal of shaping the future of the Internet, we’re focused on recruiting the best and the brightest, no matter what.

Cloudflare hires the best people based on an evaluation of their abilities and effectiveness.  We don't discriminate against employees on the basis of any other personal characteristic or any classification protected by federal, state or local law.

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