Senior Performance Engineer (VPN)

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, debugging, manipulating, and performance profiling tools.
• Proven ability to analyze latency, throughput, and stability metrics across multiple layers (client, OS, transport, application).
• Proficiency in Python (or similar scripting language)
• Familiarity with network emulation and simulation tools (e.g., 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 Haves

• Experience with Rust/C/C++/System development

What You'll Be Doing

• Design and own Proton VPN’s performance framework, defining metrics and KPIs that reflect the real-world experience of users (time-to-connect, throughput, latency, stability, reconnection rates, etc.).
• Develop distributed testing systems that simulate real network conditions, including low bandwidth, packet loss, and high-latency scenarios.
• Continuously measure and analyze performance across platforms (desktop, mobile, backend) 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 dynamically to variable network conditions.
• Serve as the performance champion within the engineering organization, mentoring others and driving a data-driven performance culture.

Perks and Benefits

• Office First: Collaboration is easier and more effective in person, with offices in multiple locations allowing for a hybrid work environment.
• Technology: Provided tools and software to excel in your role.
• Food: Daily lunch and snacks provided at the office.
• Transport: Support for transport costs through various means based on office location.
• Stock Options: Ownership of the company through stock options.
• Flexible Working: Define your working hours within team meeting constraints.
• Learning and Development: Commitment to professional growth with training programs, conferences, and continual learning opportunities.
• Employee Benefits: Comprehensive health insurance, retirement savings options, vacation policies, and wellness programs.
• Work that Matters: A community-first organization built on user trust and support, putting users first in everything it does.