R&D Engineer (VPN)

Job description

A better internet, where privacy is the default, is possible. Building this better internet might seem daunting or even unthinkable, but at Proton, this is what we do every day.

Proton was founded in 2014 by a group of scientists who met at the European Organization for Nuclear Research (CERN). Our first product, Proton Mail, is now the world’s largest encrypted email service. Subsequent Proton products, such as Proton VPN, Proton Calendar, and Proton Drive, give our users full control over how and with whom their data is shared.

Today, Proton makes privacy universally accessible. Journalists from outlets like The Guardian and The New York Times, some of the world’s largest organizations, and people in more than 180 countries have signed up for over 70 million accounts. Our diverse and dynamic team is made up of more than 400 members representing over 40 different nationalities. While we are based in Geneva, Switzerland, we have offices in Zurich, Prague, London, Vilnius, Skopje, Taipei, and many more employees working remotely around the world.

Join one of Europe’s fastest-growing companies to help us solve challenging problems and build new products that will reach hundreds of millions of people. We want to create more than just one of the world’s most impactful tech companies; we want to create a new internet that serves the interests of all people. We need you, your voice, your ideas, and your ambition to make it happen


Purpose of the role

ProtonVPN runs on a distributed architecture of Linux servers and a set of apps available on each major platform (Windows, Android, iOS, macOS, and Linux) that interact with our infrastructure.

As a member of the ProtonVPN Research and Development team, you will work on maintaining the security of ProtonVPN’s infrastructure, improving its overall performance, and developing new features. On any given day, you might code in C or Rust, script in Python or Lua, create patches for the Linux kernel, or debug system-level issues on different operating systems. You will work in close collaboration with the entire ProtonVPN development team on any outstanding projects. The ideal candidate will be excited to face unique and varied challenges that require a variety of skills to resolve.


What you will do

  • Being an active member of the ProtonVPN R&D team
  • Collaborating with app developers to analyze the various complex challenges related to (but not limited to) the networking stack of Linux, macOS, iOS, Android, and Windows systems
  • Helping develop innovative solutions to improve the connectivity, stability, performance, and resilience of ProtonVPN’s infrastructure and client software, and extend their functionality
  • Contributing to existing open-source projects or creating new ones

Job requirements

  • Expert-level knowledge of operating system internals
  • Expertise with network protocols and implementation
  • A documented track record of contributions to system-level projects and applications
  • Basic understanding of software development
  • Basic understanding of the principles of quality assurance


Knowledge in the following areas is considered a plus

  • Expertise in Windows, macOS, or Linux system development
  • Extensive experience working with Linux kernel, Windows drivers, or macOS system extensions development
  • Strong understanding of system programming languages (C/C++, Rust, Go, Python, Lua, etc.)
  • Experience with debugging code and code profiling
  • Good understanding of TCP/IP protocol and settings (e.g., congestion algorithms)
  • Strong understanding of VPN protocols (particularly IKEv2, OpenVPN, and WireGuard)
  • Experience with cryptography concepts (e.g., TLS certificates and public key infrastructure)


Why you should join Proton 

  • Be part of a movement - Proton is not just a product or service but a community-driven movement united by a shared vision of online freedom. Our services are open source, audited, and supported by community contributions. We give back to our community by maintaining core encryption libraries and supporting organizations that advance the same goals as us. Proton is free, open source, neutral, independent, and community first, while remaining financially sustainable.
  • Work with smart and dedicated people - Our team is diverse, collaborative, and tight-knit, with people coming from all walks of life. Many members of our team spent time at the world’s top academic institutions, including MIT, Harvard, Stanford, Princeton, Caltech, Cambridge, and ETH.
  • Join a strong brand - Our encrypted email service – Proton Mail - has grown to be a staple of online security and privacy. Proton has been featured in multiple popular television and film productions, such as Mr. Robot, Knives Out, Sounds of Metal, and more.
  • Grow with us - We’re one of Europe’s fastest-growing companies. Our growth gives you limitless career and educational opportunities as well as the opportunity to work side-by-side with many world-leading experts in their fields.
  • Have your voice heard - We value your opinion and encourage you to speak up and share your ideas and thoughts. At Proton, no problem is someone else’s problem. We collectively strive to do the right thing and be the undisputed best in the world at everything we do.
  • Benefits – these vary by location and type of contract but expect support on your vacation, parental leave, refreshment if working from the office, learning and development opportunities, equity for shared success, flexible working hours and remote work, company events, and team-building activities.


ProtonMail uses the Recruitee recruitment platform for a more effective hiring process and a better candidate experience. Your data will always be kept confidential and is not shared with any third parties. Keep in mind that you will receive emails from the email address careers@protonmail.recruitee.com or other addresses on the protonmail.recruitee.com domain.

Proton does not accept unsolicited resumes from any sources other than directly from a candidate. Proton will not pay a fee for any placement resulting from the receipt of an unsolicited offer, even in a situation when the relevant candidate is employed by Proton.