Senior Foundation Engineer (Drive) – C# / TypeScript / Rust

ppJoin Proton Drive's Foundation team to build the core SDK that ships to every Drive client. Daily work in C#, TypeScript, and Rust with Swift and Kotlin bindings for mobile. Foundational work: a crypto model revamp plus a Rust-based next-gen SDK on the roadmap. Geneva (preferred) or London. /p h3Responsibilities /h3 ul li- Build and maintain the core Drive SDK powering every Proton Drive client (web, mobile, desktop) /li li- Work daily in C#, TypeScript, and Rust with Swift and Kotlin mobile bindings /li li- Contribute to the crypto model revamp and next-gen Rust SDK /li li- Design and build libraries for client applications across platforms /li li- Ensure correctness, security, and reliability of foundational cryptographic infrastructure /li /ul ul liCompetitive salary /li liOnsite in Geneva or London /li liWork on privacy infrastructure used by 100M+ users /li liProfitable, no VC control — mission can't be changed by investors /li liMajority owned by nonprofit Proton Foundation /li /ul h3Requirements /h3 ul li- 5+ years of professional software engineering experience /li li- Strong Rust expertise: ownership, concurrency, performance /li li- Experience building libraries for client applications (web/mobile/desktop) /li li- C# and TypeScript proficiency /li li- Geneva or London based (onsite role) /li /ul h3About Proton /h3 pProton builds the privacy-first alternative to Big Tech: Mail, VPN, Drive, Pass, Calendar, and Lumo AI. Profitable, no VC control, and majority owned by the nonprofit Proton Foundation — so no one can force a change in mission. 100M+ users worldwide. The Drive Foundation team builds the core SDK powering every Proton Drive client. /p pCompany Size /p pPrivacy Tech / Cybersecurity / Open Source /p /p #J-18808-Ljbffr