Senior Android Engineer - Retail (SS) in London

We don't think we're exaggerating when we say we have one of the most exciting data sets in the country. The insights we gain help us build scalable, high-performance products using cutting-edge technology, products that give our customers an amazing shopping experience, including our award-winning SmartShop app.

In an inclusive, agile environment, you'll have the space to be curious, experiment, and solve complex real-world challenges. Best of all, you'll see your work in the hands of millions of people across the UK.

As a Senior Android Engineer, you'll play a key role in shaping the future of our mobile platforms. You'll lead the design and delivery of high-quality Android solutions, influence technical direction, mentor engineers, and help establish engineering best practices across teams. Working closely with Product, Design, and Engineering partners, you'll drive innovation and ensure our Android experiences remain scalable, resilient, and customer-focused.

• Lead the design, development, and evolution of large-scale Android applications using modern Kotlin-based technologies.
• Own complex technical deliveries, driving solutions from discovery and architecture through to implementation and production support.
• Define and influence mobile architecture, engineering standards, and technical strategy across multiple products and teams.
• Mentor and support engineers, fostering technical growth and a culture of continuous improvement.
• Collaborate with Product Managers, Designers, Architects, and Engineers to translate business objectives into scalable technical solutions.
• Drive engineering excellence through modern software practices, automation, code quality, testing, observability, and CI/CD.
• Contribute to platform-level initiatives, shared libraries, and cross-platform capabilities, including Kotlin Multiplatform.
• Identify and address technical debt, performance bottlenecks, scalability challenges, and security concerns.
• Champion customer experience, accessibility, reliability, and maintainability in all engineering decisions.
• Actively contribute to the wider engineering community through knowledge sharing, technical leadership, and innovation.

• Extensive commercial experience developing complex Android applications using Kotlin, including advanced use of Coroutines, Flows, Retrofit, Hilt, Room, Coil, Navigation Components, and Jetpack libraries.
• Experience contributing to or leading adoption of Kotlin Multiplatform (KMP) solutions across Android platforms.
• Expert understanding of modern Android architecture patterns, including MVVM, Clean Architecture, modularisation, and scalable application design.
• Proven track record of leading the end-to-end delivery of mobile products across the full software development lifecycle.
• Strong experience designing technical solutions and influencing architectural decisions within large-scale engineering environments.
• Deep understanding of software engineering fundamentals, including testing, security, performance optimisation, observability, and CI/CD.
• Advanced experience with automated testing frameworks including JUnit, Mockito, Turbine, and UI testing approaches.
• Experience mentoring engineers, providing technical leadership, and driving engineering best practices within teams.
• Ability to influence technical roadmaps, balancing customer needs, business goals, and long-term platform sustainability.
• Strong stakeholder management and communication skills, with the ability to explain complex technical concepts to both technical and non-technical audiences.
• Experience collaborating effectively within cross-functional and cross-platform engineering teams.
• Demonstrated ability to identify and resolve complex technical challenges while maintaining a focus on quality, scalability, and delivery outcomes.

• Strong experience with Jetpack Compose and modern declarative UI development.
• Knowledge of backend technologies, APIs, cloud-native architectures, and distributed systems.
• Experience building and maintaining shared mobile platforms, SDKs, or reusable engineering capabilities.
• Experience working with AI, ML, or intelligent product features.
• Active contribution to engineering communities through mentoring, conference speaking, blogging, or open-source projects.

• You are recognised as a senior technical leader within your team and broader engineering community.
• Teams adopt architecture and engineering practices you've helped define.
• Engineers grow through your mentoring and technical guidance.
• Mobile applications remain performant, resilient, secure, and scalable for millions of customers.
• You help shape the future direction of Android engineering within Sainsbury's Tech.

• Generous colleague discount across Sainsbury's, Argos, and Habitat.
• Competitive holiday allowance.
• Private Health Care.
• Bonus scheme.
• Pension plan.
• Flexible / smarter working policy.
• Access to special offers on gyms, restaurants, holidays, retail vouchers and more.

Work-life balance matters to us. We offer flexibility in how, when, and where you work, combining remote collaboration with the right balance of freedom to support your life outside work.

We’d all like amazing work to do, and real work-life balance. That’s waiting for you at Sainsbury’s. Think about the scale it takes to feed the nation. The level of data, transactions and variety involved. Then you’ll realise this is a modern software engineering environment, because it has to be. We’ve made significant investment in the standards and principles that shape how we work. We iterate, learn, experiment and champion ways of working such as Agile, Scrum and XP. So you can look forward to exciting opportunities across everything from AI to reusable tech.

We are committed to being a truly inclusive retailer, so you’ll be welcomed whoever you are and wherever you work. Around here, there’s always the chance to try something new - whether that’s as part of an evolving team or somewhere else across the business - and we take development seriously and promise to support you. We also recognise and celebrate colleagues when they go the extra mile and, where possible, offer flexible working. When you join our team, we’ll also offer you an amazing range of benefits.