We’re a multi-channel, multi-brand business serving millions of customers a day, with the UK’s largest loyalty scheme and an ever-evolving set of digital platforms. All of this equals over 1.2 billion transactions each year, presenting a volume, depth and complexity of data that few can match.
We don’t think we’re exaggerating when we say we have the most exciting data set in the country. And from the insights gained, we build scalable, high-performance products using cutting-edge technology that give our customers an amazing shopping experience – like our award-winning Smartshop app. In an inclusive, agile environment, you’ll have the space to be curious, to experiment, and to solve real-world challenges. And you’ll get to see your creations in the hands of millions of people across the UK.
About the role:
As a Senior Data Engineer (Java), you’ll be a key technical leader across multiple teams, acting as a design authority within the domain and applying strong architectural and engineering principles to shape technology that improves customer experiences, drives efficiency and reduces business costs, helping us to lower prices. You’ll play a leading role in engineering performance, compliance, security and risk management, bringing strong technical judgement, mentoring others and championing the delivery of secure, reliable and high quality products for customers.
In this role, you’ll lead the design and development of real-time analytics for our sales data, taking ownership of complex technical problems and driving solutions from concept through to production. You’ll use Java (17+) with tools and frameworks such as Spring Boot, Maven and Docker to build and evolve stream processors on Kafka topics, running on Kubernetes clusters, while defining approaches for scalability, resilience, observability, operational support and performance across the domain.
We use a variety of technologies here, so you’ll need to be comfortable learning new tools and techniques and helping others adopt them effectively. We’d also like you to be yourself – analytical, curious and confident in challenging the status quo. You’ll act as a role model for engineering best practice, champion a customer centric mindset, influence technical direction across the team and mentor engineers to help grow a strong and progressive engineering community.
More about the role:
- Act as a technical design lead for the STS (Sales Transaction Service), shaping scalable event-driven solutions that process high-volume sales transactions and support critical downstream consumers.
- Set and improve engineering standards across CI/CD, containerisation, infrastructure, monitoring, alerting and operational support.
- Lead key technical decisions for services that handle real-time sales transaction data, ensuring solutions are scalable, secure, resilient and supportable in production.
- Define and promote good practices for observability, performance, testing, data quality, compliance and risk management across STS stream processing services.
- Mentor engineers through design discussions, code reviews, incident support and the effective adoption of new tools and ways of working.
- Participate in the on-call rotation, helping to support production incidents, restore service quickly and maintain confidence in business-critical transaction flows.
About you:
- Strong engineering judgement and deep knowledge of software design, distributed systems and modern architecture principles.
- A track record of shaping technical direction, influencing others and raising engineering standards across teams.
- Confidence to guide, support and challenge others on design decisions, security, quality and operational excellence.
- A strong belief in agile and lean delivery, balancing pace with quality, resilience and long-term sustainability.
- A passion for secure, customer-focused engineering and DevSecOps ways of working, with a focus on delivering high-quality products.
- Curiosity about new technologies and a proactive approach to improving team practices, engineering culture and ways of working.
Essential criteria:
- Strong Java skills, with the ability to guide implementation, refactor complex code and review technically challenging changes.
- Deep experience building, deploying and supporting Kafka-based services that process and enrich high-volume transaction events in production.
- Strong experience with CI/CD, containerisation, infrastructure as code, monitoring, alerting and broader observability practices.
- Proven experience leading technical design across teams and turning business goals into practical, scalable solutions.
- Strong testing knowledge, including strategy, automation, performance testing and maintaining confidence in changes to business-critical transaction flows.
Nice to have:
- Experience creating reusable engineering patterns, shared components or standards that support multiple teams or domains.
- Experience with data warehousing and analytics platforms, particularly Snowflake and related data tooling.
- Exposure to orchestration and batch processing tools such as Airflow, along with working knowledge of Python and SQL.
- Experience with modern data modelling approaches, including raw data vault and dimensional modelling techniques.
As well as lots of on-the-job training and endless opportunities, you’ll get:
- Colleague discount across Sainsbury’s, Argos and Habitat.
- 10% time for side projects and personal development.
- Generous holiday allowance, with the option to buy more.
- Bonus scheme of up to 20% of salary.
- Special offers on gyms, 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.
