Senior Python Engineer in London

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About Cleo
At Cleo, we’re not just building another fintech app. We’re embarking on a mission to fundamentally change humanity’s relationship with money. Imagine a world where everyone, regardless of background or income, has access to a hyper‑intelligent financial advisor in their pocket. That’s the future we’re creating.
About The Company
Cleo is a rare success story: a profitable, fast‑growing unicorn with over $200 million in ARR and growing over 2x year‑over‑year. This isn’t just a job; it’s a chance to join a team of brilliant, driven individuals who are passionate about making a real difference. We have an exceptionally high bar for talent, seeking individuals who are not only at the top of their field but also embody our culture of collaboration and positive impact.
About The Role
We are looking for a Senior Python Engineer to join our Platform engineering team at Cleo. The right candidate will support our product teams in achieving their OKRs while championing best practices in python engineering and MLOps. In this role, you’ll work directly with product teams to ensure they effectively adopt the tools, frameworks, and processes provided by the Data Platform team, enabling them to build scalable, efficient, and reliable data and ML solutions. You’ll help teams implement and operate robust python services, monitoring strategies, and cost‑efficient practices to improve their data‑driven capabilities.
At the same time, you’ll act as a crucial bridge between product teams and the Data Platform team, gathering insights on real‑world challenges, gaps, and pain points in the existing platform. By surfacing these issues and collaborating with the platform team, you’ll contribute to the continuous improvement of our internal tooling and infrastructure, ensuring it better serves the needs of our engineers and data scientists. This is an opportunity to blend hands‑on engineering with strategic impact, influencing both product success and the evolution of our data platform.
What do you need?
Software engineering and best practices – proficiency in Python, code quality and maintainability
Containerisation & orchestration – Docker, Kubernetes
Understanding value and product thinking
Experience working cross‑functionally – Ability to work with data scientists, software engineers, and product managers to align ML initiatives with business goals
Experience deploying and operating APIs – moving more into the ability to deploy/operate microservices
Strong knowledge of streaming PySpark
Experience building and managing data pipelines e.g. Kubeflow, MLflow, Airflow or Flyte
In‑depth knowledge of Python 3.x, standard libraries, and core language features
Familiarity with Django, Flask, FastAPI
Data handling – Pydantic, Pandas, SQLAlchemy
Async programming – asyncio, concurrent.futures
What do you get for all your hard work?
Company‑wide performance reviews every 6 months
Generous pay increases for high‑performing team members
Equity top‑ups for team members getting promoted
25 days annual leave a year + public holidays (+ an additional day for every year you spend at Cleo, up to 30 days)
6% employer‑matched pension in the UK
Private Medical Insurance via Vitality, dental cover, and life assurance
Enhanced parental leave
1 month paid sabbatical after 4 years at Cleo
Regular socials
We’ll pay for your OpenAI subscription
Online mental health support via Spill
Workplace Nursery Scheme
We strongly encourage applications from people of colour, the LGBTQ+ community, people with disabilities, neurodivergent people, parents, carers, and people from lower socio‑economic backgrounds.
If there’s anything we can do to accommodate your specific situation, please let us know.
UK App access: The Cleo app is no longer downloadable in the UK (but only until next year). If you’re an existing user, you’ll still have access to the app. But some features won’t be available (just for a little while). Why? 99% of our users are based in the US – where financial health is often overlooked. We’ve decided to shift our focus to where we can provide the most value and make the greatest impact for users who need it most. Then we’ll be able to apply what we learn to better support our UK users in the future.
By submitting this application, I confirm that all the information given by me in this application for employment and any additional documents attached hereto are true to the best of my knowledge and that I have not wilfully suppressed any material fact. I confirm I have disclosed if applicable any previous employment with Cleo AI. I accept that if any of the information given by me in this application is in any way false or incorrect, my application may be rejected, any offer of employment may be withdrawn or my employment with Cleo AI may be terminated summarily or I may be dismissed. By submitting this application, I agree that my personal data will be processed in accordance with Cleo AI's Candidate Privacy Notice
Seniority level
Mid‑Senior level
Employment type
Full‑time
Job function
Engineering and Information Technology
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London, England, United Kingdom