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.
The opportunity ✨
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 Senior Full Stack Engineer, you’ll lead the delivery of complex, high-impact features across both mobile and backend systems. You’ll bring deep expertise in either React Native or .NET/C#, alongside strong hands-on experience in the other, and will be expected to operate confidently across the full stack.
We are deliberately hiring engineers who are strong in one domain but credible and effective in the other—whether that’s a mobile-first engineer who understands backend systems deeply, or a backend-first engineer who can confidently contribute to mobile development.
Working within a dedicated product team, you’ll play a key role in shaping solutions, guiding implementation, and raising engineering standards across a platform used by millions of customers.
What you’ll be doing 🚀
You’ll take ownership of delivering features end-to-end across the Avios App, working across both React Native and .NET/C# to build scalable, reliable solutions. While you’ll naturally lead in your core area of expertise, you’ll also contribute meaningfully across the wider stack—collaborating with teammates to ensure features are designed and delivered holistically rather than in silos.
Day to day, you’ll work closely with engineers, QA, Product Managers and Designers to break down complex problems and turn them into well-designed, production-ready solutions. You’ll be expected to bring strong technical judgement, helping to shape implementation approaches, challenge decisions where needed, and ensure a high bar for quality, performance and maintainability.
You’ll also play an important role in supporting the wider team—contributing to code reviews, mentoring other engineers, and helping to continuously improve engineering practices across the platform. This includes identifying opportunities to improve scalability, reliability and developer experience, as well as contributing to a culture of ownership and continuous improvement.
What we need from you ⚡
Strong experience delivering customer-facing applications at scale
Deep expertise in either React Native or .NET/C#
Strong hands-on experience in the other — able to confidently read, debug and contribute to production code
Experience delivering features end-to-end across mobile and backend systems
Clear understanding of how mobile and backend systems interact in a production environment
Strong understanding of APIs, distributed systems and cloud environments (AWS preferred)
Experience with CI/CD, automated testing and modern engineering practices
Ability to contribute to technical discussions and influence implementation decisions
Experience mentoring engineers and raising engineering standards
Strong communication and collaboration skills
We might not be right for you if:
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.
The Blend 📍
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 will be required to spend at least two days per week in the office, with the rest of the time working from home. You may also be required to work from one of our other office or partner locations, based on your role and 'to do' list
What Makes Us Special
You do! Our people bring the energy, the warmth, and the ideas that make the business extraordinary. As we grow, you’ll have the chance to grow too — with real opportunities to develop your skills and your career.
Diversity and Inclusion
Our vision is to create a more rewarding world of travel and experiences. Delivering that requires diverse thinking and inclusive leadership.
We are committed to building a workplace where people feel they belong and are valued for their perspective. Inclusion drives better decisions, stronger performance and more innovative outcomes.
We actively encourage applications from people with different experiences and backgrounds, and are committed to ensuring our recruitment process is fair, inclusive and accessible.
Diversity and Inclusion
Our vision is to create a more rewarding world of travel and experiences. Delivering that requires diverse thinking and inclusive leadership.
We are committed to building a workplace where people feel they belong and are valued for their perspective. Inclusion drives better decisions, stronger performance and more innovative outcomes.
We actively encourage applications from people with different experiences and backgrounds, and are committed to ensuring our recruitment process is fair, inclusive and accessible.
StudySmarter Expert Advice🤫
We think this is how you could land Senior Full Stack Engineer (React Native / .NET) in London
✨Join Local Tech Meetups
Get out there and mingle with fellow developers by joining local tech meetups. It’s a fantastic way to meet people who might be working at IAG Loyalty or know someone who does. Plus, you can pick up some trendy tech skills and trends while you're at it!
✨Contribute to Open Source Projects
Show off your coding chops by jumping into open-source projects. Not only does this give you practical experience, but it also gets you noticed in the dev community. You'll create a killer portfolio that speaks volumes about your skills to IAG Loyalty.
✨Tap into Online Developer Communities
Don’t underestimate the power of online developer communities like GitHub, Stack Overflow, and even Reddit. Participate in discussions, share your projects, and build your visibility. We can often find opportunities through these channels that can lead to a full-time gig at companies like IAG Loyalty.
✨Explore Job Boards Specifically for Tech Roles
Keep your eyes peeled on job boards that focus on tech roles. Sites like TechCareers or Stack Overflow Jobs can often have listings for companies like IAG Loyalty that might not show up on broader job sites. Make it a habit to check these regularly, and don’t hesitate to apply directly through our website!
Some tips for your application 🫡
Show off your coding skills:When applying for a software engineering role, it's super important to showcase your coding skills. Make sure your CV includes your tech stack, any relevant programming languages you’re comfortable with, and examples of projects you've worked on. If you have a GitHub profile, link it up! We love to see code in action.
Tailor your portfolio:For a full-time role, we’d expect to see some solid examples of your work in your portfolio. Make sure to include at least two or three projects that highlight your problem-solving skills and your ability to work with different technologies. Focus on the projects that are most relevant to the position at IAG Loyalty.
Craft a killer cover letter:Your cover letter is your chance to stand out—make it personal! Explain why you want to work at IAG Loyalty and how your skills align with the role. Show us your passion for software development. We dig enthusiastic candidates who understand the value of collaboration and continuous learning!
Be clear and concise:When it comes to writing your CV and cover letter, clarity is key. Avoid jargon that could confuse us and stick to simple, direct language. Highlight your achievements with quantifiable results where possible, and keep everything easy to read. A well-organised application goes a long way!
How to prepare for a job interview at IAG Loyalty
✨Brush Up on Your Coding Skills
For a full-time software engineering role, it's crucial that we stay sharp with our coding abilities. Expect technical questions that might involve solving problems on the spot or discussing algorithms. Practise on platforms like LeetCode or HackerRank to get comfortable with the types of questions that often come up.
✨Know Your Tools and Frameworks
Make sure we’re well-acquainted with the tools and technologies listed in the job description. Familiarise ourselves with any specific frameworks or programming languages mentioned. If IAG Loyalty uses React or Node.js, for instance, be ready to discuss how we’ve used them in previous projects or coursework.
✨Showcase Your Projects
Bring along a portfolio that highlights our best work. This could be code samples, GitHub repositories, or any side projects we’ve built. Make sure we can talk through our thought process for each project, especially the challenges we faced and how we solved them—this shows our problem-solving skills in action.
✨Prepare for Behavioural Questions
While technical skills are key, full-time positions also require cultural fit. Be ready to discuss our previous experiences and how we handle teamwork, conflict, and deadlines. Brush up on the STAR method—Situation, Task, Action, Result—to clearly articulate our past experiences when discussing how we've contributed to a team.
