Backend Engineer – VPN

About the role

Proton’s VPN team is building the most trustworthy VPN service worldwide. As a Backend Engineer you will help create resilient, massively‑scalable systems that protect millions of users’ privacy and enable them to bypass restrictive networks.

Key responsibilities

• Design and implement backend services that support millions of concurrent VPN users.
• Collaborate with client‑app developers and product managers to meet reliability and business requirements.
• Document backend capabilities and usage guidelines for Proton VPN clients.
• Debug and maintain critical systems, such as file‑revision cleanup and quota restoration.

Required profile

• Proven experience with PHP entry‑points in a backend stack.
• Track record of building scalable solutions and leading initiatives from discovery to production.
• Strong understanding of SQL (MySQL preferred), data modelling, and caching technologies like Redis.
• Solid grasp of security best practices, HTTP/REST APIs, and basic cryptography concepts.

Required skills

• PHP
• MySQL
• Redis
• HTTP/REST API development and consumption
• Docker or similar containerisation
• Grafana and OpenTelemetry for metrics
• Python
• Rust
• OpenAPI specifications