R&D System Engineer

Job description

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.


  • 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 extend its 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 work at Proton?

  • Our startup culture means everyone’s opinion matters. You can have a significant impact.
  • We work on interesting, challenging problems every day. There is never a dull moment.
  • Our rapid growth means there are many opportunities for advancement
  • The chance to do something meaningful. ProtonMail protects dissidents, journalists, and activists. Our work saves lives.
  • Be part of something bigger. Millions of people and businesses around the world have embraced our idea of an Internet where privacy and security are the default. Join the privacy revolution that is changing the world.

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 careers@protonmail.recruitee.com email or other addresses on the protonmail.recruitee.com domain.