Principal Machine Learning Engineer

Wayfindi • TRAFFIC • Not Specified, Not Specified, United Kingdom • 6d ago

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 $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.

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.

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 Principal 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.

What you'll be doing

Training and fine-tuning models to solve customer problems across our chatbot and the bank transaction data behind it.
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. Or integrate with LLMs hosted by OpenAI, Anthropic, GCP, AWS and others.
Working cross-functionally with backend engineers, data analysts, UX writers, product managers, annotation teams, and others to ship features that improve our users' financial health.
Taking the initiative to propose & lead technical work towards problems that were previously unknown or poorly understood. Driving change at the pillar and chapter level that affects multiple squads.
Keeping Cleo at the forefront of NLP by driving the adoption of appropriate state-of-the-art techniques and communicating the team's successes and learnings at the company level & beyond.
Mentoring & advising colleagues on their choices of models, architecture, and evaluation, promoting best practices for how we use LLMs.

Here are some examples, big and small, of the kinds of product feature work our ML Engineers have taken part in over the last year:

Building AI Agents to explore and derive insights from users transactional data
Developed deeper understanding of users finances through models extracting meaning from transactional data. Think about your bank statement, how often do you not know what a transaction is?
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
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.

Whatever problem you tackle, and whichever team you join, your work will directly impact those most in need, helping to improve their financial health.

What we're looking for

Experience in industry machine learning roles where you guided the technical approach taken by a team or department, for example as a tech lead or principal/staff engineer
Breadth of knowledge about NLP models and LLMs, with a track record of impactful projects using them.
Excellent knowledge of Python for both data science and production code
Top tier communication skills, to be able to partner with Product and Engineering Leaders
Big picture thinking to correctly diagnose problems and productionise research
Industry-leading contributions to your field, communicated through conferences, blogs, talks, or open-source projects
An understanding of probability and statistics fundamentals

What do you get for all your hard work?

What do you get for all your hard work?
A competitive compensation package (base + equity) with bi-annual reviews, aligned to our quarterly OKR planning cycles. You can view our public progression framework and salary bandings here:
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.

Other benefits

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 and activities, online and in-person
We'll pay for your OpenAI subscription
Online mental health support via Spill
Workplace Nursery Scheme
And many more!

Welcoming Everyone

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.

Download the Test Flight

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:

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. 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 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's Candidate Privacy Notice

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