Senior Android Software Engineer (Kotlin)

TL;DR

Senior Android Software Engineer (Kotlin): Building and optimizing privacy-first mobile products for Proton Drive and account infrastructure with an accent on Kotlin, Jetpack Compose, and Rust integration. Focus on end-to-end feature ownership, scalable mobile architecture, and delivering high-quality user experiences for millions of global users.

Location: Must be based in London (Onsite)

Company

Proton is a privacy-focused technology company founded by CERN scientists, providing encrypted email, VPN, and cloud storage services to millions worldwide.

What you will do

• Develop and ship high-quality Android features using Kotlin and Jetpack Compose.
• Collaborate with product and design teams to define and implement privacy-focused mobile experiences.
• Take end-to-end ownership of features from technical design to delivery and iteration.
• Contribute to the development of a shared Rust logical core for cross-platform consistency.
• Mentor engineers and help raise the technical bar within the mobile team.
• Ensure high performance, scalability, and maintainability of mobile architectures.

Requirements

• Extensive experience building and shipping high-quality Android applications using Kotlin.
• Strong experience with Jetpack Compose and modern Android development practices.
• Proven ability to take end-to-end ownership of features and technical design.
• Strong understanding of mobile performance, concurrency, multithreading, and memory management.
• Experience building maintainable, scalable, and testable mobile architectures.
• Must be based in London and able to work from the office.

Nice to have

• Experience with privacy, security, encryption, or sync systems.
• Experience with offline-first architectures.
• Rust programming experience.

Culture & Benefits

• Opportunity to work on privacy-focused products with real-world impact.
• Stock options for all employees.
• Generous leave, health coverage, and retirement options.
• Daily catered lunch and snacks in the office.
• Flexible working hours focused on outcomes.
• Support for public transport, bike allowances, or parking.