Senior R&D Engineer
Proton VPN is hiring a Senior Performance Engineer to lead efforts in making Proton VPN the fastest, most resilient, and most reliable VPN service in the world. The role defines and drives the measurement, analysis, and optimization of Proton VPN's end-to-end performance across clients, platforms, and global infrastructure, ensuring every connection is fast, stable, and private regardless of the user's location or network.
Responsibilities
- ▹Design and own Proton VPN's performance framework, defining metrics and KPIs (time-to-connect, throughput, latency, stability, reconnection rates)
- ▹Develop distributed testing systems that simulate real network conditions such as low bandwidth, packet loss, and high latency
- ▹Continuously measure and analyze performance across platforms and regions to identify bottlenecks and regressions
- ▹Collaborate with backend, R&D, and client teams to optimize protocol handling, connection setup, routing, and encryption performance
- ▹Create dashboards, reports, and automated alerts to track global performance health
- ▹Contribute to the design of resilient connectivity strategies that adapt to variable network conditions
- ▹Serve as the performance champion within the engineering organization and mentor others
Requirements
- ▹5+ years of experience in performance engineering or systems QA, ideally in networking, VPNs, or distributed systems
- ▹Knowledge of network protocols (TCP/IP, UDP, TLS, WireGuard) and performance profiling tools
- ▹Proven ability to analyze latency, throughput, and stability metrics across multiple layers (client, OS, transport, application)
- ▹Proficiency in Python or a similar scripting language
- ▹Familiarity with network emulation and simulation tools (tc/netem, iperf, IPTables/nftables)
- ▹Experience with monitoring and observability stacks (Grafana, Prometheus, Loki) and CI/CD pipelines
- ▹Cross-platform experience with Linux, macOS, Windows, Android, and iOS preferred
Nice to have
- ▹Experience with Rust/C/C++/system development
Soft skills
What we offer
- ▹Office-first culture with offices in Geneva, Zurich, Prague, Barcelona, Paris, London, Vilnius, Skopje, and Taipei; work from home up to 30% of the time
- ▹All devices and software needed for the role
- ▹Lunch and snacks provided in the offices
- ▹Transport cost support
- ▹Stock options
- ▹Flexible working hours
- ▹Learning and development opportunities
- ▹Comprehensive health insurance, retirement savings, generous leave, and wellness programs
About the company
Proton VPN enables millions of people to connect securely and privately, even where the internet is restricted or unreliable. Proton was founded in 2014 by CERN scientists, is a community-first organization funded only by user subscriptions, is profitable without VC funding, and employs over 500 people across 50+ countries.