Senior Data Scientist — Fraud & Risk AI Leader

DolarApp; Greater London; On-site; GBP 90,000 - 130,000; Full time

Benefits offered by this job

Stock options

Discretionary bonus

Latest tools & technology

Office policy: 3-4 days in-office

Job summary

ARQ seeks a Senior Data Scientist to build the intelligence layer behind our financial products. You’ll create ML models that detect fraud, prevent losses, and guide decisions at scale, moving from idea to production in collaboration with Product, Engineering and Operations.

You will work with Python on large datasets, deploy production models, monitor performance and continuously improve business impact, helping shape ARQ's AI capabilities across teams.

Qualifications

• 5+ years of experience in Data Science, ML, Software Eng or related fields.
• Strong Python skills and experience with large-scale datasets.
• Proven experience deploying ML models to production.
• Strong understanding of supervised learning techniques (classification).
• Experience with anomaly detection, fraud prevention, risk modeling or related domains.
• Ability to translate business challenges into data-driven solutions.
• Experience working cross-functionally with Product, Engineering and stakeholders.
• Strong communication skills and pragmatic problem solving.
• Comfortable operating in fast-moving environments with ownership.

Responsibilities

• Design, build, and deploy ML models for financial crime and risk challenges.
• Work on fraud detection, chargeback prediction, anomaly detection, identity verification, and monitoring.
• Translate ambiguous problems into measurable ML solutions.
• Partner with Product and Operations to define requirements and metrics.
• Analyze large datasets to identify patterns, opportunities, and risks.
• Build and maintain production-ready data pipelines and model-serving solutions.
• Monitor model performance and continuously improve accuracy and impact.
• Collaborate with Data/Backend Engineering to operationalise ML at scale.
• Shape the future of AI and ML capabilities across ARQ.

Skills

Python

Large-scale data

Production ML

Supervised learning

Anomaly detection

Fraud prevention

Risk modeling

Cross-functional collaboration

Communication

Fast-moving environment

Job description

ARQ seeks a Senior Data Scientist to build the intelligence layer behind our financial products. You’ll create ML models that detect fraud, prevent losses, and guide decisions at scale, moving from idea to production in collaboration with Product, Engineering and Operations.

You will work with Python on large datasets, deploy production models, monitor performance and continuously improve business impact, helping shape ARQ's AI capabilities across teams.