Proton is seeking a Senior Engineer in Barcelona to join high-impact product teams. This role involves building privacy-first applications like Proton Pass and Proton VPN. Candidates should have extensive experience in developing iOS applications and a strong focus on product quality and user experience. Proton offers impactful work, stock options, learning opportunities, and benefits that prioritize employee wellbeing. Join a company that values your contributions and allows versátil working arrangements.