Applied Cryptography Engineer

Geneva, Zurich, Vilnius, Switzerland

Full Time
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Posted 6 days ago

Applied Cryptography Engineer

Job description

ProtonMail was started by scientists and engineers from CERN in 2013 to make end-to-end encrypted email as easy to use as Gmail. Since then, we have grown to become the world's premier secure email service with over 10 million users and a profitable business model. We are rapidly scaling our talented teams to improve our core email product as well as to build an entire suite of web services that safeguards privacy in the digital age.

At ProtonMail, we have prioritized the research and development better cryptographic tools and processes. We currently maintain OpenPGP.js, the world's most widely used JavaScript cryptography library, as well as a cryptography library written in Go that is used by our mobile and desktop applications. In addition to maintaining and expanding these libraries, ongoing cryptography-related projects include building a key verification system, source code verification, and preparing for post-quantum crypto. All this work is meant to be compatible with and contribute to the wider OpenPGP community.


Why work at ProtonMail

  • The opportunity to have a big impact in an international company and the opportunity for rapid growth
  • Your work will have a direct and visible impact on the development of the company
  • Your work will directly impact millions of people worldwide
  • Informal culture with an emphasis on self-management
  • A friendly and casual office environment
  • ProtonMail operates as a strict meritocracy and we offer competitive salaries that grow according to your performance.


  • Strong background in computer science (algorithms, data structure, software design, reliability, maintainability, etc)
  • Knowledge of JavaScript and/or Go (the two languages in which our cryptography libraries are written)
  • Strong English communication skills
  • Experience with secure application development, a good understanding of security best practices, and a keen eye for potential vulnerabilities
  • High-level knowledge of cryptographic building blocks, including what they guarantee and when and how to use them


The following are considered a plus:

  • Low-level knowledge of crypto primitives, how they work, and how to securely implement them
  • Experience developing crypto libraries
  • Experience reading, implementing and perhaps even writing RFC-style specifications
  • B.S. and/or M.S. in Computer Science or Mathematics (or equivalent)


ProtonMail is using Recruitee recruitment platform for more effective hiring and better candidate experience. Your data will be kept confidential and not shared with any third parties.

Keep in mind that you will receive emails from email or other addresses on the domain.