Staff Software Engineer - Java - React (Digital & Payments) in London

hackajob is collaborating with Sainsbury's DTD to connect them with exceptional professionals for this role.

As a Staff Engineer, you'll be a hands‑on technical leader who drives engineering excellence across multiple teams. You’ll work on complex, high‑scale systems, design solutions that support millions of customer interactions, and help teams deliver high‑quality, robust and scalable products. This is a role for someone who loves solving tough problems, mentoring engineers, influencing technical direction, and operating across a broad architecture landscape. You’ll work closely with engineering leaders, peers and stakeholders to set strategic direction, raise engineering standards, and deliver real value for our customers. You’ll also help us leverage AI and automation to scale our capabilities and enhance both colleague and customer experiences.

What You’ll Be Doing

• Shaping strategic technical direction alongside the Senior Head of Engineering.
• Partnering with engineering teams to evaluate decisions, influence design, and guide delivery.
• Acting as a coach and mentor to engineers at all levels, promoting strong engineering practices.
• Providing hands‑on development expertise where it matters most.
• Working across domains in Sainsbury’s Tech to build reusable, consistent and scalable solutions.
• Being a trusted technical point of contact, supporting teams to achieve their best work.
• Helping expand our engineering career pathways and improving how we attract and develop talent.

Why Join Us?

We’re a 150‑year‑old organisation with the mindset of a modern tech company. We run over 1,000+ microservices in AWS, Azure and GCP. Stream billions of Kafka messages across our platforms. Serve 10+ million Nectar users. Power Argos — one of the UK’s biggest retail websites. Operate large‑scale supply chain systems delivering products across the UK. You’ll broaden your technical knowledge, solve complex engineering challenges and make a genuine impact at enterprise scale.

Essential Criteria

Technical Expertise

• Significant hands‑on engineering experience across backend and frontend technologies.
• Strong proficiency in at least one modern programming language (e.g. Java, React, Next.js).
• Proven experience designing and implementing scalable, robust and secure systems.
• Strong knowledge of cloud platforms (AWS, Azure or GCP) and modern distributed architectures.
• Proven ability to guide teams in best practices, engineering principles and solution design.

Leadership & Influence

• Ability to mentor, coach and technically inspire engineers at all levels.
• Experience influencing technical decisions and aligning teams around a clear engineering vision.
• Strong communication and stakeholder management skills.

Ways of Working

• Solid understanding of Agile methodologies and the ability to support high‑performing, long‑lived teams.
• Ability to evaluate risk, drive continuous improvement and support teams through change.

Mindset

• Customer‑obsessed, adaptable and eager to embrace new challenges.
• Passionate about innovation, learning, and delivering high‑quality solutions.

What’s In It For You

• Flexible working tailored to your lifestyle.
• Colleague discount across Sainsbury’s, Argos and Habitat.
• Health cover and wellbeing support.
• Competitive holiday allowance.
• Bonus scheme and pension plan.
• Exclusive discounts on gyms, restaurants, travel, retail and more.

Benefits

We are committed to being a truly inclusive retailer, so you’ll be welcomed wherever you work. You’ll have the chance to try something new — whether that’s as part of an evolving team or somewhere else in 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. 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 and 15% off at Argos every pay day. 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 20% of salary, depending on how we perform. Your wellbeing is important to us. 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, interest‑free car loan of up to £10k, cycle to work scheme, health cash plans, pay advance (where you can access some of your pay before pay day) as well as 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, you will also be eligible for private healthcare too. 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.