Senior Machine Learning Scientist, FinCrime

EngineersOfAI; Greater London, Cardiff; On-site; GBP 93,000 - 120,000; Full time

Job summary

Monzo is seeking a Machine Learning Scientist to join a multidisciplinary squad and deploy advanced ML models that detect fraud and protect customers. You will own end-to-end work from business problem to production solution, shaping scalable, globally deployed systems.

You will write production Python, work with SQL and Go, collaborate with data scientists, engineers, and risk teams, and continuously justify approaches with measurable impact.

Qualifications

• Proven track record deploying ML models that solve real business problems with measurable impact.
• End-to-end ownership from business problem to production solution.
• Experience building scalable ML systems for a fast-moving tech environment.
• Strong Python production coding experience and SQL fluency.
• Willingness to learn Go and work with backend microservices.
• Excellent communication and ability to explain complex topics clearly.

Responsibilities

• Develop and deploy advanced ML models to detect fraud while minimising impact on genuine users.
• Adapt ML systems to evolving fraud trends and ensure long-term performance.
• Design scalable ML solutions that operate globally and reliably.

Skills

Python

SQL

Go

Machine Learning

Deep Learning

Graph ML

Sequence ML

Tools

Git

Docker

Kubernetes

Go

Job description

Monzo: Role overview

We are reshaping banking by solving real problems for customers and making money work for everyone.

Over the past 10 years in the UK, our product offering has expanded from prepaid cards to personal and business bank accounts, joint accounts, accounts for 16-17 year olds, a free kids account, and credit cards. Our UK customers can save, invest, and combine their pensions with us. With smart cards, faster payments, financial education on social media, and award-winning customer service, we have a track record of creating meaningful moments for our customers. We are focused on solving problems and changing lives through Monzo.

Location & benefits

Cardiff, London or Remote UK | Salary £93,000 - £120,000 + incentive awards tied to performance | Benefits

Responsibilities

This role sits as part of a multidisciplinary squad, collaborating with other Machine Learning Scientists, Data Scientists, Backend Engineers, Operations specialists, Product managers, and Risk managers. You will leverage your deep experience of developing and deploying advanced Machine Learning models to:

• Automatically and accurately detect suspicious user behaviours while minimising impact to genuine customers and operational costs.
• Adapt quickly and appropriately to changing fraud and financial crime trends, ensuring detection systems remain performant over time.
• Design machine learning solutions that scale globally.

The technical approaches you take will be in your hands; we encourage experimentation and innovation. You should justify and demonstrate effectiveness along the way, ensuring the approach meets business and customer needs.

Qualifications / You should apply if

What we’re doing at Monzo excites you!

• You have a track record of deploying advanced Machine Learning models that tackle real business problems with demonstrable impact, preferably in a fast-moving tech company.
• You're impact-driven and eager to own end-to-end work from a business problem to a production solution with measurable impact.
• You have a passion for sharing knowledge and raising the technical bar across the team.
• You have a self-starter mindset; you proactively identify impactful issues and opportunities and tackle them collaboratively.
• Using advanced ML techniques to ensure customer money stays safe, even if their card, phone, or account is compromised, excites you.
• You have extensive experience writing production Python code and a strong command of SQL. You are comfortable using them daily and keen to learn Go which is used in many backend microservices.
• You have experience developing and shipping deep learning, graph-based, and/or sequence-based ML architectures to production with business impact.
• You thrive when working on ambiguous problems and help your team and stakeholders resolve ambiguity.
• You have strong communication skills and can explain complex topics clearly.