Join Proton and build a better internet where privacy is the default Proton was founded in **** 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.
We are profitable, independent (no VC control), and selectively hire from the top ~1% of applicants.
If you want to do meaningful work with exceptionally high-caliber people, this is it.The Foundation Team The Foundation team builds what the product teams build on: the shared backend framework, the internal libraries, the common services and abstractions that every Proton application reaches for.
If several teams need it, it should exist once, and be good.
You will work in PHP for API related work, and in Rust for components where performance and memory safety justify it or for microservices.
You will own libraries or initiatives end to end: design, implementation, documentation, versioning, and the migration path for everyone already depending on the old version.
Architecture is a large part of this role.
You will help define those boundaries, make the structural calls that keep teams from stepping on each other, and do some work to enforce them: writing the RFC, adding rules, untangling the cycle that shouldn't have been there.
What you will do Design and build shared libraries, framework layers, and internal services used across every Proton product Turn recurring patterns into good abstractions Write documentation and examples people actually use,



and treat adoption as part of shipping Improve the day-to-day: build times, local dev setup, test ergonomics, debuggability, developer experience Work in the open with product teams — RFCs, design reviews, and the occasional pull request into someone else's repo to show what you mean Work closely with other developers to help integrate libraries seamlessly into applications Job requirements: 5+ years building and operating backend systems in production, including code you stayed responsible for long after launch, with a focus on modern PHP Working knowledge of Rust, or clear evidence you can get there quickly — we care that you understand ownership and lifetimes Genuine taste in API design.
You have opinions about naming, defaults, error handling, and what belongs in a library versus a service A feel for architecture at codebase scale — you have worked somewhere large enough that module boundaries and dependency direction mattered, and you have views on what keeps a monorepo healthy Experience evolving shared code that other teams depend on, and doing it without breaking them A security mindset.
Domain-Driven Design, or similar experience modelling complex domains where the boundaries matter Background in developer tooling, platform, or DX teams Contributions to open source,



especially libraries with real users Experience migrating a codebase incrementally between architectures or languages Experience with applied cryptography, key management, or end-to-end encrypted systems Experience with building CI/CD What We Offer Work that Matters: millions of people trust Proton with their privacy.
Technology: you'll get the right hardware and the right software you need to do your best work.
We offer strong health coverage, solid retirement options, generous leave, and wellness support so you can bring your best self to work every day Stock Options: at Proton, we all have the opportunity to be owners of the company.
Transport: getting to the office shouldn't cost you.
Adaptable Working: you own your schedule.
If you need any extra support or reasonable adjustments during the hiring process, please let your talent partner know.
Candidate Privacy Notice When you apply for a position, refer a candidate, or are considered for a role at Proton Technologies AG (Proton, we, us, or our), your information is stored in Greenhouse, in accordance with theirService Privacy Policy.We also retain this information for consideration for future roles that you may apply for or that we believe may align with your background and skills.
If we no longer have a legitimate business need to process your information, we will either delete or anonymize it.
Should you have any inquiries about how we use or manage your information, or if you wish to access, correct, or delete your data, please contact our privacy team at Proton does not accept unsolicited resumes from any sources other than directly from candidates.

📌 (Senior) PHP Backend Engineer (Barcelona)
🏢 Proton
📍 Barcelona