Fullstack Engineer in London

We’re proud to work with one of the most exciting data sets in the UK. Our massive datasets, comprising billions of data points from diverse sources across the retail landscape, drive machine learning models that enhance personalisation and product recommendations. This work directly impacts millions of customers daily. In our inclusive, agile environment, you’ll have the freedom to explore, experiment, and solve real-world challenges—seeing your creations in the hands of millions across the UK.

Why join us

You’ll be part of one of our Engineering squads working on Ad-tech, interpreting and following architectural and engineering principles, operating frameworks, and new and improved technology and solutions. With your technical craft, curiosity and experimentation, you’ll use judgement to apply specific techniques to deliver focused outcomes that support our customers. We use a variety of tech here and you need to be willing to pick up new tools and techniques. We’d also like you to be yourself - analytical, curious and unafraid to challenge the status quo. You’ll constantly strive to improve the way things are done in your team, contributing as a progressive member of the engineering community.

About the role

• Build UI components and, sometimes, whole user routes from Figma designs, in React.
• Write Typescript on the website’s front-end, back-end and in-between: full stack.
• CSS-style the UI’s using Tailwind and CSS Modules, while harnessing design tokens.
• Actively contribute to developing large-scale services for optimal performance, utilising technologies like Node.JS, Typescript, Mongo DB, Postgres, SQL, AWS Lambda, GraphQL and Serverless framework.
• Be proficient in unit testing (TDD), end-to-end testing and best practices.
• Collaboratively contribute to the design and support of services and internal frameworks.
• Actively participate in research, scoping, and planning activities led by engineering and product managers for the development of new domain and platform capabilities.
• Troubleshoot and resolve issues in production web applications, databases, services, and related components.
• Actively participate in the support rota, providing timely assistance to ensure system reliability.
• Foster team growth and development by providing support and mentorship to teammates, both through collaborative efforts, direct pair programming sessions and PR reviews.
• Familiar with trunk-based development and CI/CD pipelines using GitHub actions.

Our tech stack:

• JavaScript/Typescript - especially Winston and package management (using npm)
• Frontend: React
• Backend: AWS Lambdas
• AWS Lambda, SQS, SNS, IAM, SES, Cloudwatch, Cloudfront, Secrets Manager, GraphQL, MongoDB, Serverless Framework & Terraform, New Relic

Essential Criteria

To be considered for this role, you should possess industrial experience and have a strong passion for working with:

• Relevant degree or equivalent qualification.
• Well-versed writing, maintaining and reviewing TypeScript code at production.
• Serverless infrastructure and AWS ecosystem.
• Modern React with hooks, experience writing unit tests (Vitest, RTL) for components.
• Modern CSS styling: Tailwind, CSS Modules, style-dictionary and design tokens.
• Redux experience is valued but not required - we use React Query.
• Writing and maintaining E2E on Playwright (but Cypress experience will be counted too).
• Extensive experience in developing and utilising enterprise APIs.
• Proficiency in SQL and NoSQL databases.
• Customer-focused, owning the entire SDLC, and embodying DevOps principles.
• Proven experience in software design and implementation, security, cloud infrastructure & monitoring CI/CD.
• Enthusiastic about continuous learning, especially in emerging tech.

What I need to show

• A positive approach to change.
• A solution-focused mindset with creativity and adaptability.
• Good communication skills and the ability to navigate complex corporate governance environments.
• Attention to detail.

While not mandatory, having the following qualifications can give you a competitive edge:

• Proficiency in AWS (AWS Certification is a plus).
• Competence in Terraform.
• Exposure in event-driven architectures is a plus.

Benefits

As well as lots of on-the-job training and endless opportunities, you’ll get:

• Colleague discount across our multi-brands – Sainsbury’s, Argos, Tu and Habitat.
• Holiday allowance.
• Bonus scheme.
• Pension plan.
• Special offers on gym memberships, restaurants, holidays, retail vouchers and more.

Work-life balance is important to us, so we offer our colleagues as much flexibility as possible in line with the needs of their role. We trust them to decide how, where and when they work, combining remote and collaborative working with a flexible approach to hours, giving them plenty of time and space for life outside of work whilst delivering against our business goals.

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. Here are some of them:

• Starting off with colleague discount, you'll be able to get 10% off at Sainsbury's, Argos, TU and Habitat after 4 weeks. This increases to 15% off at Sainsbury’s every Friday and Saturday.
• We've also got you covered for your future with our pensions scheme and life cover.
• You'll also be able to share in our success as you may be eligible for a performance-related bonus of up to 10% of salary, depending on how we perform.

Your wellbeing is important to us too. You'll receive an annual holiday allowance, and you can buy additional holiday. We also offer other benefits that will help your money go further such as season ticket loans, cycle to work scheme, health cash plans, pay advance (where you can access some of your pay before pay day) as well access to a great range of discounts from hundreds of other retailers. And if you ever need it there is also an employee assistance programme.

Moments that matter are as important to us as they are to you which is why we give up to 26 weeks’ pay for maternity or adoption leave and up to 4 weeks’ pay for paternity leave.

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.