Description We're looking for a Senior Software Engineer to play a pivotal role in shaping and evolving M&S's campaign personalisation and paid media platforms. This team provides the intelligent services that power personalised, performance-driven campaigns across web, mobile, and paid channels — helping millions of customers see the right message, in the right place, at the right moment, while making every pound of media spend work harder. Your "customers" are marketing and media teams, engineers, data scientists, and ultimately millions of M&S customers. Your mission is to improve the relevance, efficiency, and measurable return of paid media and personalised campaigns through robust engineering, intelligent optimisation, and production-ready systems. This is a role for an engineer who is excited by performance marketing, personalisation at scale, and building customer-facing products that move commercial metrics. You will help drive the next phase of growth for M&S's paid media and personalisation stack as it continues to evolve across our digital channels. Due to high interest, this role may close earlier than advertised. We recommend applying as soon as possible. About the Team We’re building the personalisation Campaign and Paid Media engineering platform that underpins every customer touchpoint, with a true omnichannel mindset across web, app, email, push and paid social. This is a high-ownership, high-visibility Software Engineering role for an engineer who wants to shape how millions of people discover and experience M&S, through intelligent systems that acquire and engage customers and support Marketing activity. You will join the team responsible for the platforms behind M&S's paid media and personalisation — live, customer-facing systems that combine audience intelligence with automated campaign delivery to drive relevance and return on ad spend. What You'll Do Your key accountabilities will include: Build and evolve paid media and personalisation services using Python, supporting highly scalable, customer-facing campaign delivery. • Drive continuous improvement of paid media performance through structured experimentation, A/B testing, and data-driven insights. • Build integrations with paid media platforms (paid search, paid social, programmatic/DSPs) to automate audience activation, bidding, and budget management. • Work with attribution and measurement systems, identifying opportunities to improve spend efficiency and customer outcomes. • Integrate campaign and personalisation services into broader digital platforms, APIs, martech, and adtech ecosystems. Who You Are A strong software engineer with extensive Python experience delivering production-grade applications and services. • Knowledge of building performance marketing or personalisation products paid media platforms, bidding/budget optimisation, or customer-facing campaign systems. • Hands-on experience designing and implementing measurement, attribution, or experimentation frameworks. • Comfortable working with large-scale data and using it to drive continuous improvement in commercial metrics. • Strong understanding of how to measure marketing and media performance and translate it into engineering outcomes. • Comfortable taking ambiguous, fast-moving marketing challenges and translating them into practical, scalable solutions. What’s in it for you Being a part of M&S is exactly that – playing your part to bring the magic of M&S to our customers every day. We’re an inclusive, dynamic, exciting, and ever evolving business built on doing the right thing and bringing exceptional quality, value, service to every customer, whenever, wherever and however they want to shop with us. Here are some of the benefits we offer that make working for M&S just that little bit more special After completing your probationary 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. • Competitive holiday entitlement with the potential to buy extra holiday days! • Discretionary bonus schemes awarded based on how you achieve your personal objectives and our performance as a business. • A generous Defined Contribution Pension Scheme and Life Assurance. • A dedicated welcome to our teams with a tailored induction and a wide range of training programmes to develop your skills. • Amazing perks and discounts via our M&S Choices portal to maximise your financial and personal wellbeing. • Leading parental, adoption and neonatal policies, providing support and flexibility for your family. • Access to a fantastic range of wellbeing support for all colleagues including access to our 24/7 Virtual GP and PAM Assist to support you and your family. • A charity volunteer day to support a charity or cause you're passionate about through a dedicated day away from work. 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. Location: London (Hybrid – 1 day per week in the office) #hybridrole #LI-CJ1 #LI-HYBRID