Full-Stack Engineer

Who we are

We’re IAG Loyalty - one organisation with two ambitious, growing divisions across Loyalty and Holidays. Each has its own goals, strategy and team, but together we’re united by a shared vision to create a more rewarding world of travel and experiences.

Our Loyalty division is home to Avios, the global loyalty currency, enabling millions of members to collect and spend rewards across travel, retail and financial services.

Our Holidays division including British Airways Holidays and Iberia Vacaciones, brings together trusted brands, connecting customers to thousands of destinations worldwide through seamless, end-to-end travel experiences.

We’re on an exciting journey of growth and transformation – we’re going places.

Join IAG Loyalty and help shape the continued development of the Avios App, a global loyalty platform used by millions of travellers worldwide. As a Full Stack Engineer, you’ll deliver scalable, high-quality features that enhance the mobile experience across the Avios ecosystem.

Working within a dedicated mobile product team, you’ll contribute across React Native, .NET/C#, and AWS, building end-to-end solutions that power meaningful customer features. You’ll be part of a modern, agile engineering environment where collaboration, curiosity, and continuous improvement are encouraged.

This is a chance to work on a high-traffic consumer application with real impact, supporting a platform that connects with major airline partners including British Airways, Iberia, and Aer Lingus, while sharing knowledge and contributing to the team’s technical growth.

You’ll play a key role in delivering new features and improvements for the Avios App, working across both mobile and backend technologies to build scalable, reliable solutions used by millions of customers. As part of a collaborative, agile product team, you’ll develop end-to-end features using React Native and .NET/C#, contributing hands‑on code while helping maintain high standards of performance, reliability, and user experience across the app.

Working closely with engineers, QA, product managers, and designers, you’ll help deliver features iteratively, solve technical challenges, and support smooth delivery across the platform. You’ll also contribute to code reviews, technical discussions, and best practices within the team, while sharing knowledge and mentoring other engineers to help strengthen the wider engineering community.

• Strong full‑stack engineering experience across mobile/front‑end and backend development.
• Hands‑on experience with React Native.
• Strong development experience in .NET and C#, building scalable APIs and services.
• Experience working with AWS, ideally including serverless technologies.
• Good knowledge of modern engineering practices such as CI/CD, automated testing, and clean code.
• Experience delivering features in agile, collaborative teams.
• Ability to troubleshoot and solve problems across distributed systems.
• Experience with RESTful APIs, microservices, and event‑driven architectures.
• Strong communication skills and a collaborative mindset.
• A willingness to mentor and support other engineers.
• Interest in building mobile products at scale used by millions of customers.

• You only want to focus on your to‑do list; we’re a small, high‑performing team, we help each other to succeed.
• You value perfection over fast iteration and progress; IAG Loyalty moves fast, we learn and iterate as we go; our environment isn’t right for everyone.
• You’re looking to create but not build; this is an end‑to‑end role, you need to be comfortable owning your space, from ideation through to delivery and review.

If you think you have what it takes but don’t meet every single point above, please do still apply. We’d love to chat and see if you could be a great fit.

This role will work as part of our Loyalty Division and is based out of our London office. We call our approach to hybrid working The Blend— it’s about giving you the flexibility to choose where you do your best work, while staying connected with your team and the wider business. This means you…