Foundation Engineer
Posted 17 Sep 2025
Advertised as “Senior Foundation Engineer (Drive)”
BranchFactor Summary
The original posting with the fluff stripped out
- Expected experience
- 5+ yrs
- Management level
- Individual contributor
- Employment
- On-Site
No salary listed for this role.
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. In some situations, Proton has literally helped save lives!
We are profitable, independent (no VC control), and selectively hire from the top ~1% of applicants. Our 500+ team members across 50+ countries come from leading organizations and elite academic backgrounds. We move fast, keep hierarchy light, and prioritize impact over optics. If you want to do meaningful work with exceptionally high-caliber people, this is it. Join us and do work you can truly be proud of. Check our open-source projects here!
Drive Foundation
Drive Foundation is the backbone of Proton Drive. We ensure that cross-client initiatives are executed consistently and efficiently. Whether it’s aligning multiple clients, maintaining documentation or the RFC process, or building robust SDKs, our team lays the groundwork that makes the entire Drive experience work seamlessly.
- Current Projects:
- We’re currently focused on developing SDK that encapsulate the core functionality of Proton Drive. The SDK comes with two core implementations, one in C# for desktop and mobile clients and second in TypeScript for web client, and higher-level modules in Rust. Our SDK primarily serve internal clients today, but our long-term vision includes integrating them across the Proton ecosystem—and even enabling third-party applications to interface with Drive.
- Tech Stack and Tools:
- Languages we see daily is C#, TypeScript and Rust. We also need to provide bindings for Swift and Kotlin. We use Grafana and Prometheus to instrument our SDK, Sentry to get details issues from the SDK usage, GitLab CI for running tests including e2e tests written using Playwright, or GitLab in general to work on the code base.
- Future Plans:
- We are planning to revamp our cryptographic model to boost performance and efficiency across all clients. We will finish ongoing first generation of SDK to cover all core Drive features and new crypto model. Then we will do second generation in Rust with lessons learned and include full support of all features such as Photos, Public Sharing, and Docs.