Windows 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

We are looking for an enthusiastic Windows software engineer to become part of our ProtonVPN team. ProtonVPN clients support all major platforms, including Windows. We want to build a secure product that is competitive on usability, functionality, and stability, to offer our users the best VPN experience. 

What you will do

You will be an active part of the ProtonVPN Windows team through tasks including :

  • Improving and extending the ProtonVPN clients by building user interfaces, optimising network protocols, and creating Windows kernel drivers
  • Taking part in the development of innovative solutions to improve the interface, usability, connectivity, stability, performance, and resilience of ProtonVPN and extend its functionality
  • Collaborating in the analysis of complex challenges related to various aspects of a Windows system, related but not limited to its networking stack

  • Taking part in extending existing open source projects or in creating new one

  • Taking part in close collaboration with the entire ProtonVPN development team in any outstanding projects

Job requirements

  • Expert-level knowledge of Windows

  • Good knowledge of the C# and .Net ecosystem 

  • A documented track record of contributions to multiple Windows projects and applications

  • Strong software engineering skills such as CI/CD

  • Knowledge of the networking stack (especially on the Windows environment)

  • Basic understanding of the principles of quality assurance


Bonus points for 

  • Windows Kernel driver development

  • VPN protocols such as OpenVPN, IKEv2 or WireGuard

  • Windows system administration

  • Code debugging and profiling

  • HTTPS certificates and public key infrastructure

  • Agile methodologies and frameworks

  • Open source software development


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 by supporting other organizations furthering 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, including many of the world’s top academic institutions and organizations, such as MIT, Harvard, Stanford, 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 startups, doubling in size every year. 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.


Proton 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. You will receive emails from the email address careers@protonmail.recruitee.com or other addresses on the protonmail.recruitee.com domain as part of the recruitment process.


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 where Proton employs the relevant candidate.


By applying to a role at Proton, you acknowledge that we will process and store your personal data for at least the duration of the hiring process and as necessary to enter a contractual relationship with you.