Proton

Software Engineer, Windows (VPN)

Proton
Apply
18 days ago
Barcelona, SpainSenior

Responsibilities

  • Design, build, maintain, and evolve Proton’s Windows VPN applications.
  • Contribute across the full application lifecycle, including feature design, implementation, CI/CD configuration, deployment, monitoring, and operational incident response.
  • Develop and integrate Windows application functionality using C#/.NET and WinUI.
  • Define, maintain, and improve unit, integration, and automated GUI testing using FlaUI.
  • Collaborate with product managers and engineers across the company to deliver privacy-preserving products.
  • Drive technical change and lead complex technical projects.
  • Support gradual rollouts and observability through telemetry, metrics, monitoring, and alerting.
  • Debug, profile, and optimize application performance on Windows.

Requirements

  • Strong experience with C# and .NET development.
  • Strong experience building and maintaining Windows desktop applications with WinUI, WPF, or similar frameworks.
  • Knowledge of MVVM architecture, dependency injection, asynchronous programming with async/await, and event-based messaging patterns.
  • Experience writing maintainable, well-tested, and scalable codebases.
  • Experience driving organizational change and leading complex technical projects.
  • Strong understanding of software architecture and engineering best practices.
  • Working knowledge of networking fundamentals, including TCP/IP, DNS, and routing concepts, plus interest in VPN technologies and protocols.
  • Experience with debugging, profiling, and performance optimization on Windows.
  • Familiarity with Git-based workflows, GitLab CI/CD pipelines, and collaborative development practices.
  • Experience with gradual rollouts and observability tooling such as telemetry, metrics, monitoring, and alerting.
  • Rust experience is a significant plus.
  • Appreciation for user experience and design quality.

Benefits

  • Health coverage, retirement options, generous leave, and wellness support.
  • Stock options and an ownership stake in the company.
  • Flexible working hours and schedule ownership.
  • In-person collaboration at offices including Geneva, Zürich, Barcelona, and London; the listing is marked onsite.
  • Company-provided hardware and software.
  • Lunch and snacks provided in offices.
  • Public transport coverage, bike allowances, or parking support.
  • Opportunities for learning, development, and meaningful ownership from day one.

Tech Stack

C#Git.NETRustWindows

Categories

Proton

About Proton

501-1,000 employees
Contact me