Senior Machine Learning Engineer
HarnhamAbout the role
Senior Machine Learning Engineer / Machine Learning Scientist (Fraud Detection)
USA Remote | $160,000 to $210,000 base + bonus + equity
This is a high-impact opportunity to work on machine learning systems that directly influence real-time financial decisions at scale. You will take ownership of experimentation and production models that sit at the heart of a fraud prevention platform, with the autonomy to shape how models are built, evaluated, and deployed.
The Company
They are a well-established fintech business operating at global scale, providing AI-driven fraud protection for e-commerce transactions. Their platform enables online retailers to approve more genuine customers while protecting against fraudulent activity, backed by a financial guarantee model. With a strong international presence and a customer base spanning thousands of merchants, they process large volumes of transactions across multiple markets. Machine learning is central to their product, with continued investment in their in-house ML infrastructure and experimentation capabilities.
The Role
Own end-to-end machine learning development, from experimentation through to production deployment and monitoring
Design and implement scalable ML pipelines to support fast, high-quality experimentation
Develop and improve fraud detection models, including ensemble approaches and decision systems
Build robust offline evaluation frameworks to validate model performance before release
Collaborate with product, engineering, and risk teams to translate business challenges into ML solutions
Contribute to best practices across model development, testing, and monitoring
Your Skills & Experience
Strong commercial experience in machine learning, with a solid grounding in statistics and model evaluation
Proven ability to design and run experiments and translate findings into production systems
Experience working in distributed computing environments, including Spark
Proficiency in Python and SQL, with experience building scalable data and ML pipelines
Deep understanding of supervised and unsupervised learning techniques in high-scale environments
Ability to own complex problems end to end and deliver measurable business impact
What They Offer
Base salary between $160,000 and $210,000, depending on location and experience
Annual bonus up to 10% and a stock option package
Comprehensive benefits including healthcare, retirement plans, and wellbeing support
Unlimited paid time off and a dedicated learning and development budget
A collaborative, research-minded environment with strong technical standards and ownership
How to Apply
If you are interested in applying your machine learning expertise to high-impact fraud detection systems, please submit your CV to learn more.
Responsibilities
- Own end-to-end machine learning development, from experimentation through to production deployment and monitoring
- Design and implement scalable ML pipelines to support fast, high-quality experimentation
- Develop and improve fraud detection models, including ensemble approaches and decision systems
- Build robust offline evaluation frameworks to validate model performance before release
- Collaborate with product, engineering, and risk teams to translate business challenges into ML solutions
- Contribute to best practices across model development, testing, and monitoring
Qualifications
- Strong commercial experience in machine learning, with a solid grounding in statistics and model evaluation
- Proven ability to design and run experiments and translate findings into production systems
- Experience working in distributed computing environments, including Spark
- Proficiency in Python and SQL, with experience building scalable data and ML pipelines
- Deep understanding of supervised and unsupervised learning techniques in high-scale environments
- Ability to own complex problems end to end and deliver measurable business impact
Benefits
- Annual bonus up to 10% and a stock option package
- Comprehensive benefits including healthcare, retirement plans, and wellbeing support
- Unlimited paid time off and a dedicated learning and development budget
- A collaborative, research-minded environment with strong technical standards and ownership
Skills mentioned
About Harnham
Harnham provides specialist Data and AI recruitment and staffing services, along with bespoke training solutions, across multiple industry verticals, operating in the UK, the USA and EU - contact us today to discuss your requirements: info@harnham.com Our recruitment and talent teams cover all aspects of the data and AI pipeline, from collection to consumption, across multiple data roles and functions. Whether you need full-time staff, contract talent, specialized training, Data-qualified graduates, or C-suite executives, Harnham Group is equipped to fulfill all your data talent requirements. Our five core services: * ATD - Rockborne – our graduate development arm – deploys expertly trained data consultants, who have gone through an intensive 12-week data training programme. After two years in the scheme, your consultant could become a * Contract / C2C / Freelance: Whether you're addressing a talent shortage, augmenting a project team, or encountering resource gaps, our specialist consultants offer bespoke interim talent solutions to address your unique challenges and drive success. * Full-Time / Direct Hiring: From early career professionals to senior management, our comprehensive services enable you to unearth outstanding data talent across various specializations, ensuring your organization thrives in the data-driven era. * Executive Search: With our dedicated executive search team and an extensive network encompassing the director to C-suite level, we assist both global corporations and ambitious startups in securing top-tier leadership talent to accomplish their goals. * GenAI, Prompt, LLM Training: Elevate your team's data expertise with our all-encompassing training programs covering essential tools and technologies such as Python, SQL, Machine Learning, LLM’s and AI. Highly bespoke, customised to your team learning requirements and budgets.
H-1B sponsorship history
Historical employer filing data was found for Harnham. The employer record includes 1 historical certified applications. This is employer-level history, not a guarantee that this role currently offers sponsorship.