Staff Software Engineer (IBM Sterling) in London

The M&S Online Fulfilment area is looking for a Staff Software Engineer to join our Promising team. You will provide technical expertise, lead the design and delivery of robust solutions, and operate with excellence. Creative, curious and pragmatic, you will lead the modernisation of our order management software to provide a seamless customer experience and enable M&S’s online growth ambitions through a scalable, reliable, secure and cost‑effective system.

As part of the M&S Software Engineering team, you'll be joining a well‑loved historic brand, working on solutions that serve millions of loyal customers and thousands of colleagues! With ethical values that run right through the company's core and technology leaders that truly understand software engineers and engineering, it's an exciting time as we're redefining ourselves into a digital‑first and engineering‑led organisation, with the quality of our engineering team being a key differentiator.

The Promising team is on a multi‑year journey to build the platforms and services that will provide accurate delivery details to our customers. We sit at a critical junction in the retail ecosystem, and our ambition is to provide accurate, real‑time delivery and collection options so customers can get the products they want, when and where they want them. Our team is steadily evolving towards a future where reliable availability and delivery data from resilient systems create a market leading experience for our customers, driving brand loyalty and revenue.

In this role, you will play a key part in driving our ambition to create a best‑in‑class software engineering team, environment and culture. Join our community of engineers to help build a modern digital ecosystem, work with cutting‑edge technologies, and do the best work of your career.

What you’ll do

• Build and evolve order management and promising capabilities – design and enhance resilient services, APIs and integrations that support accurate delivery promises, inventory visibility, and fulfilment decisions across digital and retail channels. Your work will help ensure customers see reliable availability and delivery options throughout the order journey.
• Own features end‑to‑end – take responsibility for design, development, testing, deployment and production support of our promising platform. You will balance delivery speed with long‑term sustainability, ensuring the platform remains reliable, maintainable and scalable.
• Shape the technical direction of our Promising Platform – help evolve the services, integrations and decisioning that power how we source, promise and fulfil orders across stores, distribution centres, suppliers and digital channels. You’ll design solutions that balance promise accuracy, integration reliability, operational resilience and cost to serve, using modern engineering practices to build a platform that other teams and customer journeys can depend on.
• Champion engineering excellence – write clean, maintainable, well‑tested code and help establish best practices across multiple teams. You will encourage a continuous improvement culture through code reviews, pair programming, and high‑quality documentation.
• Drive operational excellence and observability – share responsibility for the reliability of our data integrations. Use observability tools such as Dynatrace to design for monitoring and alerting and participate in our support rota to ensure supply‑chain and pricing data remains accurate and available.
• Collaborate widely – work closely with Product Managers, cross functional engineering teams and other Fulfilment teams to solve real business problems in thoughtful and innovative ways. Cross‑functional decision‑making and breaking down information silos are essential to shortening time to value.
• Mentor and support colleagues – provide coaching and feedback to more junior engineers. Help grow our community of practice by sharing knowledge and fostering an inclusive environment.

Who you are

• A strong technical leader – you bring deep backend engineering experience and a track record of shaping reliable, scalable systems in complex enterprise environments. You are comfortable guiding technical direction and influencing decisions beyond your immediate team.
• Experienced in the IBM Sterling order management product suite and the fulfilment domain – you understand the technical and operational challenges involved in inventory visibility, promising, sourcing and fulfilment, with experience implementing IBM Sterling products to tackle these challenges.
• Strong in Java and enterprise integration – you are confident building services, APIs and integrations that operate reliably across a varied systems landscape, and you write clean, maintainable code with a strong focus on long‑term sustainability.
• Operationally excellent – you care about CI/CD, observability, production support and release quality, and you design systems with resilience, recoverability and supportability in mind.
• Pragmatic and commercially aware – you balance technical ambition with delivery, understand the impact of engineering choices on customer experience and operational outcomes, and make sensible trade‑offs in service of the wider business.
• Collaborative and improvement‑focused – you enjoy working across disciplines, raising engineering standards and helping teams adopt better tools, practices and ways of working.

What’s in it for you

• Being a part of M&S is exactly that – becoming a part and playing your part. We’re an inclusive, dynamic, exciting and always evolving business built on core values.
• 20% colleague discount on most things from furniture, fashion and food.
• A first‑class welcome to M&S with a tailored induction and a wide range of training schemes to help with your learning and development.
• Attractive annual bonus, based on company performance and personal objectives.
• Competitive holiday entitlement with the potential to buy extra holiday days.
• Amazing perks and discounts via our M&S Choices website – including GymSave and the option to become an M&S Shareholder.
• Charity Volunteer Day – a paid day away from work to support your chosen charity.
• A very generous Defined Contribution Pension Scheme and Life Assurance.
• Access to a fantastic range of wellbeing support – including our 24/7 Virtual GP and other wellbeing schemes.