Senior Backend Engineer - Better Matching Experience in London

Depop is a peer-to-peer circular fashion marketplace where anyone can buy, sell and discover secondhand fashion. Our mission is simple: to make fashion circular by making secondhand as exciting and rewarding as buying new. Founded in 2011, Depop’s diverse community has helped move resale into the mainstream, where buying secondhand is no longer an alternative, but how people of different ages now engage with fashion. Today, more than 56 million registered users come to Depop to find great value, express their own personal style and give clothes a longer life. We believe that everything you want already exists, and our role is to help people discover it.

We aim to create an inclusive environment where everyone is welcome, no matter who they are or where they’re from. Just as our platform connects people globally, we believe our workplace should reflect the diversity of the communities we serve. We thrive on the power of different perspectives and experiences, knowing they drive innovation and bring us closer to our users. We’re proud to be an equal opportunity employer, providing employment opportunities without regard to age, ethnicity, religion or belief, gender identity, sex, sexual orientation, disability, pregnancy or maternity, marriage and civil partnership, or any other protected status. We’re continuously evolving our recruitment processes to ensure fairness and are open to accommodating any needs you might have.

Depop is looking for an experienced Senior Backend Software Engineer to join the Better Matching Experiences (BMX) team permanently. BMX owns Depop’s product discovery and personalisation experience — the highest traffic surfaces in the platform and the largest user facing surface area across Depop’s engineering organisation. The team builds and evolves the search, recommendations, and personalisation platform that powers how millions of users discover inventory across the marketplace. This is a cross-functional squad of Backend and iOS Engineers working closely with Product, Data Science, ML Scientists and Design partners, operating in a fast moving, experiment driven environment where user behaviour insights directly shape what we build and how we iterate.

As a Senior Backend Engineer in BMX, you will have a unique opportunity to shape, evolve and scale our discovery and personalisation systems. You will influence how we migrate to modern architectures and help establish strong engineering foundations as we accelerate new user success and continuous discovery.

What you will be doing:

• Independently design and deliver backend solutions to medium-to-large problem spaces, from discovery through production and iteration.
• Build and evolve core discovery services, pipelines and APIs that power personalisation at scale.
• Help improve search relevance and recommendation quality by working at the intersection of backend engineering and ML-powered personalisation.
• Take end-to-end ownership of your work, including design, implementation, testing, observability, and operational support.
• Contribute to shaping technical direction within the team, improving system design, reliability, and developer experience.
• Operate in an experiment-led environment, helping define hypotheses, success metrics, and feedback loops.
• Collaborate closely with Product, Data Science, Design, and other Engineering teams to ensure solutions are well scoped and well understood.
• Actively contribute to continuous improvement through retrospectives, post-incident reviews, and technical discussions.
• Mentor and support other engineers in the team, raising the overall quality of delivery.

Why this role is exciting:

• You will shape discovery and personalisation systems that directly influence how millions of users find what they love on Depop.
• You will work at the intersection of product engineering and data science.
• You will have real ownership over meaningful problem areas across search, recommendations, and the personalisation platform.
• You will see direct, measurable impact from your work through experiment results and user engagement metrics.
• You will help drive a significant architectural evolution as we modernise our service layer.
• You will join a team that values experimentation, learning, and pragmatic engineering excellence.

What are we looking for:

• Experienced in backend engineering fundamentals with experience independently delivering production systems.
• Proficiency in at least one backend language such as Scala, Java or Typescript, with the ability to learn new languages quickly.
• Experience working with data-intensive systems, including designing, consuming, and evolving data models across services.
• Experience building or operating event-driven systems, such as producing and consuming events or messages in distributed architectures.
• Experience building scalable and reliable services and APIs.
• A strong sense of ownership paired with effective collaboration and communication.
• Comfort working in ambiguous problem spaces and proactively shaping solutions.
• Solid testing practices across unit and integration levels.
• Experience working in a DevOps-oriented environment including CI/CD and production monitoring.

Desirable Experience:

• Experience with search or recommendation systems (e.g. OpenSearch, Elasticsearch).
• Experience working alongside ML/data science teams on personalisation or relevance problems.
• Experience in experiment-led or hypothesis-driven teams with strong data and insights practices.
• Experience in marketplace or eCommerce environments.
• Hands-on experience with message brokers or streaming platforms such as Kafka or similar technologies.
• Experience with Docker and Kubernetes.
• Familiarity with AWS infrastructure and infrastructure-as-code tooling.

Additional Information:

• Health + Mental Wellbeing: PMI and cash plan healthcare access with Bupa, subsidised counselling and coaching with Self Space, Cycle to Work scheme with options from Evans or the Green Commute Initiative, Employee Assistance Programme (EAP) for 24/7 confidential support, Mental Health First Aiders across the business for support and signposting.
• Work/Life Balance: 25 days annual leave with option to carry over up to 5 days, 1 company-wide day off per quarter, Impact hours: Up to 2 days additional paid leave per year for volunteering, Fully paid 4 week sabbatical after completion of 5 years of consecutive service with Depop.
• Flexible Working: MyMode hybrid-working model with Flex, Office Based, and Remote options *role dependant.
• All offices are dog-friendly.
• Ability to work abroad for 4 weeks per year in UK tax treaty countries.
• Family Life: 18 weeks of paid parental leave for full-time regular employees, IVF leave, shared parental leave, and paid emergency parent/carer leave.
• Learn + Grow: Budgets for conferences, learning subscriptions, and more, mentorship and programmes to upskill employees.
• Your Future: Life Insurance (financial compensation of 3x your salary), pension matching up to 6% of qualifying earnings.
• Depop Extras: Employees enjoy free shipping on their Depop sales within the UK. Special milestones are celebrated with gifts and rewards!