Senior Android Developer

Based in City of London, Guardian is a rapidly growing, progressive business that offers its employees career development in a fast-paced, collegial working environment.

We offer Recruitment services designed to meet our clients’ individual business needs - from planning stages and all the way through to onboarding and induction. Whilst striving to deliver excellence in our working practice, we support clients in the end to end recruitment process.

We are seeking a skilled Senior Android Developer to join our engineering team.

Responsibilities

• Lead the design, development, and maintenance of a large-scale Android application serving fintech products and services.
• Build modern, accessible, and high-performance user experiences using Jetpack Compose.
• Architect and implement scalable dependency injection solutions using Dagger Hilt, following industry best practices.
• Write clean, maintainable, and testable code aligned with Clean Architecture principles.
• Design and implement security-critical features required for financial applications, including SSL pinning, data encryption, certificate validation, and secure session management.
• Develop secure payment solutions in compliance with PCI-DSS standards and industry regulations.
• Drive engineering excellence by actively participating in code reviews and promoting high-quality development practices.
• Collaborate closely with backend, product, and cross-functional teams to define and deliver robust API integrations.
• Monitor, analyze, and continuously improve application performance, reliability, and scalability.
• Contribute to technical decision-making, architecture discussions, and long-term platform evolution.

Qualifications

• 5+ years of professional Android development experience, including building and maintaining production-grade applications.
• Strong hands-on experience with Dagger Hilt and dependency injection patterns.
• Proven experience developing and shipping production applications with Jetpack Compose.
• Advanced proficiency in asynchronous programming using Kotlin Coroutines and Flow.
• Extensive experience integrating RESTful APIs using Retrofit and OkHttp, including implementing custom interceptors.
• Solid understanding of Clean Architecture and layered application design (Data, Domain, and Presentation layers).
• Experience working on fintech products such as digital banking, payment systems, wallets, or investment platforms.
• Strong knowledge of mobile application security, including SSL pinning, certificate validation, Android Keystore encryption, and biometric authentication.
• Deep understanding of MVVM and/or MVI architectural patterns.
• Experience writing and maintaining unit and UI tests using JUnit, Espresso, and Turbine.
• Proficiency with Git workflows and CI/CD pipelines.
• Excellent communication and collaboration skills, with the ability to work effectively in cross-functional teams.

Nice to Have

• Experience working in highly regulated environments.
• Familiarity with observability and performance monitoring tools (e.g., Firebase Performance Monitoring, Crashlytics).
• Experience mentoring other engineers and contributing to engineering best practices.
• Knowledge of secure authentication and authorization mechanisms such as OAuth 2.0 and JWT.