Senior Machine Learning Engineer, Personalisation
About The Company
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.
Cleo is a rare success story: a profitable, fast-growing unicorn with over $300 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.
If you’re driven by complex challenges that push your expertise, the chance to shape something truly transformative, and the potential to share in Cleo’s success as we scale, while growing alongside a company that’s scaling fast, this might be your perfect fit.
Follow us on LinkedIn to keep up to date with new product features and insights from the team.
About The Role
Senior Machine Learning Engineers at Cleo work on building novel solutions to real-world problems. This really does vary but could be: creating chatbots to coach our users around their financial health, creating classifiers to better understand transaction data or even optimising transactions within our payments platform.
Ultimately, we’re looking for a brilliant Senior Machine Learning Engineer to join us on our mission to fight for the world's financial health. You’ll be leading technical work within a team of adaptable, creative and product-focused engineers, who train & integrate cutting edge machine learning across a variety of products and deploy them into production for millions of users. We understand our customers, we understand their pain, and we are passionate about helping them.
Check out this blog on Isabelle's journey in ML at Cleo.
What You'll Be Doing
You'll be joining the Machine Learning Growth Personalisation team where you will work in a cross functional squad which is focused on using ML to personalise the Cleo product.
You will work on recommender systems and/or behavioural modelling (e.g multi-armed bandits, uplift modelling + other causal modelling)
Deploying these models into our production environments using our in-house ML platform, which you can read about on our blog: Let's have an Espresso: MLOps at Cleo. A chance to really own the whole process end to end!
Working cross-functionally with backend engineers, data analysts and product managers.
Taking the initiative to propose & lead technical work towards problems that were previously unknown or poorly understood. Driving change at the chapter level that affects multiple squads.
Mentoring & advising colleagues on their choices of models, architecture, and evaluation.
Here Are Some Examples, Big And Small, Of The Kinds Of Product Feature Work Our ML Engineers Across Cleo Have Taken Part In Over The Last Year
Built recommender systems for in-app prompts and notifications
Built a multi-armed bandit testing framework to enable fast and low regret multi-variate testing.
Building AI Agents to explore and derive insights from users transactional data
Built models to optimise the payment success for our customers and optimising the costs for the business. Think of this as a two-sided optimisation problem.
Developed contextual intent classifiers to understand what conversations users are having with Cleo, enabling control of how Cleo should respond
Building ML models to understand the actions that users have available to them in Cleo and provide those contextually in conversations
Built ML models to understand the risk of customers using bank transaction features and user activity
What You'll Need
Experience in Personalisation (Recommender systems and/or behaviour modelling)
Excellent knowledge of both Data Science (python, SQL) and production tools
A deep understanding of probability and statistics fundamentals
Big picture thinking to correctly diagnose problems and productionising research
Top tier communication skills, to be able to partner with Product and Commercial Leaders
Industry-leading contributions to your field, communicated through conferences, blogs, talks, or open-source projects
Advanced Degree in a quantitative discipline or equivalent commercial experience
Nice to have
Strong experience with additional programming languages, such as Java, Scala, C++
Industry-leading contributions to your field, communicated through conferences, blogs, talks, or open-source projects
The recruitment process
Interview with a Recruiter (30 mins)
Interview with the Hiring Manager (30 mins)
Python Coding Interview (45 mins)
White-boarding session (60 mins)
Technical Discussion (45 mins)
What do you get for all your hard work?
A competitive compensation package (base + equity) with 3-annual reviews, aligned to our termly OKR planning cycles.
We're hiring this position at our Senior Machine Learning Engineer (DS3) level. The salary band is:
London, UK Hybrid (1 day per week in London office): £94,059 - £115,000 gross annually
UK Remote (based outside London): £88,938 - £109,000 gross annually
Work at one of the fastest-growing tech startups, backed by top VC firms, Balderton & EQT Ventures
A clear progression plan. We want you to keep growing. That means trying new things, leading others, challenging the status quo and owning your impact. Always with our complete support.
Flexibility. We can’t fight for the world’s financial health if we’re not healthy ourselves. We work with everyone to make sure they have the balance they need to do their best work
Work where you work best. We’re a globally distributed team. If you live in London we have a hybrid approach, we’d love you to spend one day a week or more in our beautiful office. If you’re outside of London, we’ll encourage you to spend a couple of days with us a few times per year. And we’ll cover your travel costs, naturally.
Company-wide performance reviews every 4 months
Generous pay increases for high-performing team members
Equity top-ups awarded across all levels in performance reviews
25 days annual leave a year + public holidays (+ an additional day for every year you spend at Cleo, up to 30 days)
1 month paid sabbatical after 4 years at Cleo
6% employer-matched pension in the UK
Private Medical Insurance via Vitality, dental cover, and life assurance
Online mental health support via Spill
Enhanced parental leave
Workplace Nursery Scheme
Paid for access to multiple AI platforms (ChatGPT, Codex, Claude)
Access to the latest AI coding models
Pick your kit - choose between a Windows or an Apple computer
Regular socials and activities, online and in-person
And many more!
Final compensation will be determined based on the candidate's seniority, qualifications, skills, and previous experience
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.
App access for people in the UK & Europe: If you are an iOS user, please use this link to sign up to our TestFlight version of the app, so you can have a play around with the functionality and features: https://testflight.apple.com/join/fDG9hWng
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