Senior iOS Engineer (Vilnius)

About the role

Based in our Vilnius office, you will join a high‑impact product team working on Proton Drive and Proton VPN. As a Senior iOS Engineer you will help design, build and ship privacy‑first applications used by millions worldwide, shaping the user experience on Apple platforms.

Key responsibilities

• Develop and maintain high‑quality iOS applications for encrypted cloud storage and secure VPN services.
• Collaborate with product managers, designers and other engineers to define and deliver great user experiences.
• Design scalable, testable and maintainable mobile architectures.
• Optimize performance, concurrency and memory usage across large codebases.
• Mentor junior engineers and raise the technical bar within the team.
• Participate in product and technical discussions, navigating ambiguity.

Required profile

• Extensive experience building and shipping iOS applications.
• Strong focus on product quality, usability and user experience.
• Proven ability to create maintainable, scalable and testable mobile architectures.
• Comfortable working with large codebases and cross‑team collaboration.
• Experience mentoring engineers and improving team standards.
• Deep understanding of performance, concurrency and memory management on iOS.
• Interest or experience in privacy, security, encryption or offline‑first architectures is a plus.
• Rust experience is a plus, as Proton moves toward a platform‑independent Rust core.

Required skills

• iOS development
• Swift
• Apple platforms (iPhone, iPad, macOS)
• Mobile architecture design
• Performance optimization
• Concurrency and memory management
• Automated testing
• Rust (optional)

What we offer

• Impactful work protecting the privacy of millions of users.
• Stock options giving you a stake in the company.