Windows Software Engineer; VPN

Overview

Join Proton and build a better internet where privacy is the default.

Proton was founded in 2014 by scientists from CERN on a simple truth: privacy is a fundamental human right. Since then, we’ve built the world’s largest encrypted email service (Proton Mail) and expanded into Proton VPN, Proton Drive, Proton Pass, and Proton Calendar, tools used by millions globally to protect their freedom, fight censorship, and keep their data safe.

• Design, build, maintain, and evolve Proton’s applications on Windows.
• Participate in the entire application life‑cycle from feature design and implementation to CI/CD, deployment, monitoring, and incident response.
• Collaborate closely with product managers and engineers across the company to deliver privacy‑preserving products used by millions worldwide.
• Help define, maintain, and improve our testing stack, including unit tests, integration tests, and automated GUI tests.

• Strong experience in C# and .NET development.
• Experience building and maintaining Windows desktop applications using WinUI, WPF, or similar frameworks.
• Solid understanding of MVVM architecture, dependency injection, async/await, and event‑based messaging patterns.
• Proven ability to write maintainable, well‑tested, and scalable codebases.
• Demonstrated experience driving change within an organization and leading complex technical projects.
• Strong understanding of software architecture and engineering best practices.
• Appreciation for user experience and design quality.
• Working knowledge of networking fundamentals (TCP/IP, DNS, routing) and interest in VPN technologies and protocols.
• Experience with code debugging, profiling, and performance optimization on Windows.
• Familiarity with Git, CI/CD pipelines (Git Lab), and modern collaborative development practices.
• Experience with gradual rollout and observability tooling (telemetry, metrics, monitoring, alerting).
• Rust experience is not required but is a significant plus.

• Opportunities to work from home up to 30% of the time.
• Access to all devices and software needed to excel in your role.
• Lunch and snacks provided daily at our offices.
• Support for transport costs through public transport subsidies, bike allowances, or parking spaces.
• Stock options as part of our employee ownership program.
• Flexible working hours that accommodate team meetings.
• Learning and development opportunities, including training programs and conferences.
• Comprehensive health insurance, retirement savings, vacation, leave, and wellness programs.

At Proton, we believe diversity drives innovation and strengthens our mission to provide privacy as a default for all. We are committed to fostering an inclusive environment where all individuals feel valued and empowered.

When you apply for a position at Proton Technologies AG, your information is stored in Greenhouse in accordance with their Service Privacy Policy. We retain this information for future roles that may align with your background and skills. If we no longer have a legitimate business need to process your information, we will delete or anonymize it. You may contact our privacy team at careers
.