Staff Software Engineer - Experimentation

Team: Digital & Tech
Store: London Support Office
Location: London, Greater London
Contract type: Permanent
Position type: Full Time
Salary: Competitive + Benefits; Closing date: 10th August 2026

How We Hire

Everyone is welcome at M&S. No exceptions. It’s your background, abilities and differences that make you, uniquely you. And when you’re part of M&S, that individuality has the potential to make waves.

About the role

This section tells you all you need to know about the position and its responsibilities, outlining everything we hope to see in a successful candidate.

To stay close to our customers and colleagues, our support teams are in the office for at least three days a week as we believe that skills are developed through collaboration, and that spending time together makes us more creative and connected.

All the details

Staff Software Engineer – Experimentation team

We’re looking for a Staff Software Engineer to play a pivotal role in evolving M&S’s Experimentation platform. This team provides the experimentation capabilities that empower teams across the business to identify savings and drive revenue. Your customers are product teams, engineers, content teams – everyone who works on customer-facing functionality – and your mission is to enable them to run more experiments, more easily and confidently, by creating a robust experimentation platform.

This is a role for an engineer who is excited by platform thinking, enablement at scale, and revolutionising how experimentation capabilities are modelled, delivered, and accessed across a large organisation.

Due to high interest, this role may close earlier than advertised. We recommend applying as soon as possible.

What you’ll do

Your key accountabilities will include:

Design, build, and evolve backend‑heavy platform capabilities for experimentation, including APIs, services, automation pipelines, and developer tooling.
Set technical direction for the Experimentation platform, influencing architecture and standards beyond your team.
Champion a self‑service platform model, building tools, scripts, and automation (including emerging agentic AI use cases) that reduce toil and dependencies.
Partner closely with product, engineering, and content teams to understand needs, pain points, and future demand.
Mentor engineers at all levels, helping develop strong technical judgement, platform thinking, and engineering craft.
Demonstrate a production‑first mindset: observability, resilience, and safe change are core design concerns.
Produce clear, high‑quality documentation for APIs, systems, standards, and operational processes.

Who You Are

A strong platform mindset: you build capabilities and tools that power many teams, not just individual features.
Deep backend engineering experience with Java/Kotlin, including designing and running distributed systems in production.
Strong experience on the Azure cloud platform, building and operating scalable, reliable services.
Solid understanding of experimentation solutions (Optimizely experience is a strong plus).
Hands‑on experience with GraphQL — schema design, federation, evolution, and API governance (must have).
Working knowledge of TypeScript and React, particularly in API, tooling, or integration contexts.

What’s in it for you?

Working at M&S means being part of something bigger - helping to deliver quality, value and service to millions of customers every day. We’re inclusive, fast-moving and always evolving, with a strong sense of purpose and a focus on doing the right thing.

Here are just a few of the benefits that make working here even more rewarding:

20% colleague discount on all M&S products and many third-party brands for you and someone in your household, available once you’ve completed your probation
Competitive holiday allowance with the option to buy more
Strong pension and life assurance to help plan for the future
Tailored induction and training to support your development from day one
Exclusive perks and savings through our M&S Choices portal
Market-leading family policies, including parental, adoption and neonatal leave
24/7 wellbeing support, including virtual GP access and mental health services
One paid volunteer day a year to support a cause that matters to you

Everyone’s Welcome

We are ambitious about the future of retail. We’re disrupting, innovating, and leading the industry into a more conscientious, inspiring digital era. We’re transforming how we work together and offering our most exciting opportunities yet. Marks & Spencer strives to be an inclusive organisation, trusted and admired by our colleagues, customers, and suppliers.

We are committed to building diverse and representative teams, where everyone can bring their whole selves to work and be at their best. We support each other and win together.

If you’d benefit from any support or reasonable adjustments during any stage of the recruitment process, please let us know when completing your application.

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Meet the Team

A group of colleagues gathered around a table, smiling and discussing work with laptops open in a modern office setting.

Being an in-person business

We're at our best when we're close to customers, and for many of us at M&S, that means working in store every day.

To stay close to customers, our support teams are in the office three days a week as we believe that skills are developed through collaboration, and that spending time together makes us more creative and connected. It also means we can solve problems as soon as they arise, learn and grow as a team, build trust, and get closer to our colleagues.

Halford Head of Technical Program Management

At M&S, we have Data Scientists, Analysts, and Technical Product Managers, who all share a genuine passion for harnessing data to improve people’s lives. And we’re in a unique position where we can actually help many different kinds of people, from our customers to our colleagues in store and in our support centre.

Deepak (He / Him) | Data Scientist Read full story

I think all engineers just love solving puzzles and problems. At M&S, we’re constantly learning new things, whether it’s mastering Swift UI or understanding how customers interact with technology. But this is also a business that listens to engineers and values what we bring to the table. That’s different, believe me.

Janak (He / Him) | Staff iOS Engineer Read full story

Being in third-party brands, working on things M&S hasn’t done before… that plays to my sweet spot. I’ve worked in many organisations throughout my career, and it’s rare to see such cause and effect in your work. The way we’re structured means you’re encouraged to solve problems and you have the autonomy to make progress quickly.

Halford (He / Him) | Head of Technical Program Management Read full story

Make Your Mark

Upcoming projects

Take part in our M&S Digital & Tech team days. Grow your digital and data skills through our BEAM Academy. Or challenge yourself at one of our business-wide hackathons. We also partner with Women in Data, Databricks and Cajigo to increase opportunities for women in digital and data.

Opportunities to be heard

Your voice and your ideas matter here. Our 8 colleague networks are places to find support, listen to each other and encourage debate. You can pitch ideas ‘Straight to Stuart’, our CEO, or get involved in our BIG (Business involvement Group).

Colleague Networks

We want you to feel supported, no matter what.

Cancer Network

Fostering a supportive and inclusive workplace culture, addressing stigma, providing guidance and raising awareness to empower and assist colleagues affected by cancer.

LGBTQ+ Network

Proactively representing LGBTQ+ issues and opportunities to deliver a truly inclusive place to work and shop for our colleagues and customers.

Menopause Network

Initiating and encouraging open conversations about menopause by offering support and sharing experiences.

Forces Community Network

Supporting colleagues connected to the Armed Forces, aiding their transition to civilian life, and ensuring that they thrive in the workplace.

Culture and Heritage Network

Raising awareness of various religions and cultures through events and comms, to educate others and better represent our M&S colleagues and customers.

Family & Carers Network

A support network for parents and carers, offering a space for colleagues to share experiences, exchange ideas, and access useful resources.

Health and Wellbeing Network

Providing a safe space for colleagues with all types of health conditions or disabilities and supporting with business initiatives to ensure our stores are truly accessible for our customers.

Gender Equality Network

Addressing gender-related challenges, raising awareness, and driving action to ensure equal opportunities for all.

Benefits

Wellbeing hub

Get access to resources to support your wellbeing, including a free virtual GP service.
Giving back

Support your favourite charities by donating through your pay or even volunteering for them.
Pay

Earn a competitive salary.
Colleague discount

After completing your probation period, you'll receive 20% colleague discount across all M&S products and many of our third-party brands for you and a member of your household.

Please note only contracts of more than 12 weeks are eligible for this benefit.
Time off

Competitive holiday entitlement with the potential to buy extra holiday days.
Bonus

We have discretionary bonus schemes depending on your role and our business performance.
Life assurance

Get cover for twice your salary up to age 70 (double with our Pension Plan).
Workplace savings

We’ll help you save through our Pension Savings Plan, Share Buy and Sharesave schemes.
My Choices

Save on everyday costs through discounts and offers and get access to great health benefits.
Cycle to work

Bike/accessory hire with Cycle to Work and save on tax and national insurance.
Smart tech

Buy the latest technology with interest-free financing directly from your salary.
Family friendly policy

Industry-leading maternity, paternity, adoption and neo-natal policies, providing support and flexibility for you and your family.

How to Apply

Here’s what to expect at each stage of the application process. This can change depending on the role you’ve applied to. If you need any reasonable adjustments made at any stage, let us know and we can help.

Send us your application

Fill in our short application form and hit submit.

Online assessment

Depending on the role you are applying for, you may be invited to do an assessment. Your Talent Acquisition Partner will guide and inform you along the way.

Interview

We'll invite you to join us for an interview. This could be remote or in person. Here, we'll ask you some role based technical questions and examine the behaviours we're looking for.

Decision

After we’ve made our decision, we’ll be in touch. If you’ve been successful, we’ll officially invite you to join the team and let you know the next steps.