Senior Backend Engineer - Platform (Inbox)

Proton; Arare; Vor Ort; CHF 49.939 - 76.759; Vollzeit

Zusammenfassung

Proton is seeking a Senior Backend Engineer for the Platform team to architect and build core systems shared by Proton Mail and Calendar. You will focus on performance, cost‑efficiency, and data‑driven delivery while collaborating with product and engineering teams.

You should have hands‑on experience with monitoring and observability tools, strong SQL and data modelling skills, and familiarity with Kubernetes, PHP/Symfony, Rust, or Python. A full‑stack mindset is valued for this role.

Qualifikationen

• Strong experience designing, building and scaling backend systems for large user bases (100M+).
• Track record improving performance and cost-efficiency of production systems.
• Hands-on monitoring/observability tooling experience (Grafana, OpenTelemetry, etc.).
• Solid SQL skills with data modelling.
• Experience leading a technical initiative end-to-end.
• Experience with client-server sync or push-notification systems.
• Experience with containerisation (Kubernetes).
• Proficiency in PHP/Symfony, Rust, or Python.
• Full-stack capability spanning frontend and backend.

Aufgaben

• Architect and develop core systems shared by Proton Mail and Calendar.
• Improve performance and reduce costs across platform components.
• Adopt data-driven delivery and measurement to guide priorities.
• Collaborate with backend and client engineers to ensure quality and performance.
• Develop and implement comprehensive testing strategies to ensure reliability.

Kenntnisse

Backend development

Performance optimization

Monitoring/observability

SQL modelling

Kubernetes

PHP/Symfony

Rust

Python

Full-stack

Jobbeschreibung

The Team

Our business unit, Inbox, is a cross‑functional team of about 60 engineers, product managers, designers, and data analysts driving the development of Proton Mail, the company's flagship product, and Proton Calendar. Our mission is to create an end‑to‑end encrypted solution with a better user experience than any other productivity product on the market. The Platform team, a sub‑team of Inbox, builds the shared foundations, tooling and systems other Inbox teams rely on. Over the next year, the team's priority is efficiency and cost reduction.

Purpose of the role

As a Senior Backend Engineer on the Platform team, you’ll bring hands‑on experience with data‑driven delivery, monitoring, and how the team plans and prioritizes its work. You’ll work closely with the product team to design new systems, and with the rest of the team to improve the performance of what’s already running.

What you will do

• Architect and develop core systems: design and build core, cross‑product systems shared by Proton Mail and Calendar, with scale and cost‑efficiency as first‑class constraints.
• Performance: improve the performance of existing systems, using monitoring and metrics to identify where time and infrastructure spend are going and where to cut. Drive cost‑reduction and efficiency initiatives across shared platform components, from proposal to production.
• Data‑driven delivery: bring a data‑driven approach to technical decisions and delivery planning, shaping how the team measures and prioritizes its work.
• Collaboration: work closely with a team of backend and client engineers, with a strong emphasis on quality and performance in everything shipped.
• Testing: develop and implement comprehensive testing strategies, including unit tests and integration tests, to ensure the reliability of core systems.

Job requirements

• Strong experience in backend development, with a track record of designing, building and scaling systems that serve a large user base (100M+).
• Demonstrated ability to improve the performance and cost‑efficiency of systems already in production.
• Hands‑on experience with monitoring and observability tooling (e.g. Grafana, OpenTelemetry, or equivalent), and a data‑driven approach.
• Solid understanding of SQL (MySQL preferred) and data modelling.
• Experience leading a technical initiative end‑to‑end, from design through production.
• Experience with client‑server sync or push‑notification systems.
• Experience with Kubernetes or other containerisation technologies.
• Experience with PHP/Symfony, Rust, or Python.
• Full‑stack experience, comfortable working across the frontend as well as the backend.

Compensation range

Paris: 54,000€ – 83,000€ gross annually*

Other locations: Compensation will be discussed during the interview process. *Final compensation will be determined based on the candidate’s qualifications, skills, and previous experience.

Candidate Privacy Notice

When you apply for a position, refer a candidate, or are considered for a role at Proton Technologies AG, your information is stored in Greenhouse in accordance with their Service Privacy Policy. This information is used to evaluate your suitability for the posted position. We also retain this information for consideration for future roles that 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 anonymise 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 [e-mail].

Our Commitment to Diversity and Inclusion

At Proton, we believe diversity drives innovation and strengthens our mission to provide privacy as a default for all. We are committed to fostering an inclusive environment where all individuals, regardless of race, ethnicity, gender, age, sexual orientation, physical ability, or socio‑economic background, feel valued and empowered. We strive to create equal opportunities, promote open dialogue, and support continuous learning to ensure every voice is heard and respected.

If you need any extra support or reasonable adjustments during the hiring process, please let your talent partner know.