Senior Android Engineer

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 organisations and elite academic backgrounds. We move fast, keep hierarchy light, and prioritise 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

The Role
As an engineer on our Android team, you'll build and ship features across Proton's suite of Android applications, working closely with product and engineering teams to define what "great" means on the Android platform.Quality is a core expectation: you'll help maintain and expand our testing stack, including unit tests for business logic, API-stubbed pseudo-integration tests, UI snapshot coverage, and end-to-end tests. You'll join a team that combines deep technical expertise with a focus on simple, usable interfaces, shipping privacy-preserving products used by millions.

What you'll do

• Develop and maintain cross-platform mobile applications for Android using a blend of cross-platform (Rust) and native technologies (Kotlin)
• Take end-to-end ownership of mobile application development projects: you'll be comfortable with scoping projects, walking back from deadlines and being able to discern the important from the superfluous
• Foster a culture of innovation by exploring new technologies, methodologies and approaches to mobile development – we tackle complex engineering challenges with creativity and ingenuity
• Optimise mobile applications for performance, usability and responsiveness across different devices and screen sizes
• Master memory management, multithreading and concurrency mechanisms to enhance performance and responsiveness of mobile applications
• Design for scalability, considering factors such as data caching, network bandwidth and server load
• Prioritise customer satisfaction by maintaining a customer-centric mindset throughout the development process, continuously seeking feedback and iterating to improve the user experience
• Build and optimise push notification flows using FCM and Android notification channels to deliver timely, reliable  notifications while respecting modern background and battery constraints.
• experience with local data storage and sync (Room/SQLite or equivalent) for offline-capable apps

What you'll bring

• Bachelor's degree in Computer Science, Engineering or related field (or equivalent work experience)
• Excellent problem-solving skills and the ability to think outside the box to overcome challenges
• Passion for continuous learning and driving change in the rapidly evolving field of mobile development
• Excellent communication and interpersonal skills
• Proven experience developing mobile applications for Android using Kotlin as well as cross-platform technologies
• Proficiency with Jetpack Compose for Android, and familiarity with Rust
• Strong understanding of mobile app architecture, design patterns and best practices
• Knowledge of memory management techniques and best practices
• Experience with multithreading and concurrency in mobile applications
• Good understanding of scalability considerations when it comes to engineering mobile applications
• Previous experience working in a fast-paced, scale-up environment

What We Offer

• Office First: Collaboration is easier and more effective in person, which is why we have offices in Geneva, Zurich, Prague, Barcelona, Paris, London, Vilnius, Skopje, and Taipei. You can also enjoy working from home up to 30% of the time, while enjoying great company during our three core days in the office. 
• Technology: We provide all the devices and software you need to excel in your role, ensuring you have the best tools at your disposal to achieve your goals.
• Food: Lunch and snacks are provided by Proton every day at our offices.
• Transport: We will always support our employees with transport costs through subsidizing public transport, bike allowances, or parking spaces based on your office location.
• Stock Options: At Proton, we are all owners of the company and you get stock options when you join us.
• Flexible Working: You can define your own working hours as long as it works with team meetings.
• Learning and Development: We are committed to your professional growth. Proton offers various learning opportunities, including training programs, conferences and events, and continual learning.
• Employee Benefits: Comprehensive health insurance plans, competitive retirement savings options, generous vacation and leave policies, and wellness programs.
• Work that Matters: Proton is a community-first organization, started with the support of a crowdfunding campaign and built with community input. To this day, Proton's only source of revenue is user subscriptions. Over 100 million people trust and support Proton, and we put our users and community first in everything we do. Read more about our impact here.

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.

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 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 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. We will not pay a fee for any placement resulting from an unsolicited offer, even if the candidate is subsequently hired by Proton.

To learn more about our privacy policy, please visit our privacy policy page.

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