> Markdown version of [/jobs/ext/2801362-senior-data-scientist](https://www.wearedevelopers.com/jobs/ext/2801362-senior-data-scientist). Every page supports `.md` or `Accept: text/markdown`. Links point to the HTML versions so they work for humans too. Agent guide: [/agents.md](https://www.wearedevelopers.com/agents.md). --- # Senior Data Scientist - **Company:** Castleisland - **Location:** Greater London, UK - **Experience:** Expert - **Contract:** Permanent contract - **Skills:** Artificial Intelligence, Big Data, Information Engineering, Fraud Prevention and Detection, Monitoring of Systems, Python (Programming Language), Machine Learning, Software Engineering, Supervised Learning, Data Analytics, Machine Learning Operations, Data Pipelines - **Published:** September 9, 2026 - **Apply:** https://www.collegerecruiter.com/job/2858056257-senior-data-scientist ## About the Role * 5+ years of experience across Data Science, Machine Learning, Software Engineering, or related disciplines. * Strong Python skills and experience working with large-scale datasets. * Proven experience developing and deploying machine learning models in production environments. * Strong understanding of supervised learning techniques, particularly classification problems. * 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 business stakeholders. * Strong communication skills and a pragmatic approach to problem-solving. * Comfortable operating in fast-moving environments with high ownership., * Experience in financial crime, fraud prevention, AML, risk, or payments. * Experience in fintech, banking, or financial services. * Backend engineering experience and familiarity with production systems. * Experience building real-time decisioning or risk platforms. * Familiarity with modern MLOps practices and model monitoring. ## Description * Design, build, and deploy machine learning models that solve real-world financial crime and risk challenges. * Work on problems such as fraud detection, chargeback prediction, anomaly detection, identity verification, and transaction monitoring. * Transform ambiguous business problems into measurable ML solutions. * Partner closely with Product and Operations teams to define requirements, success metrics, and decision frameworks. * Analyse 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, reliability, and business impact. * Collaborate with Data Engineering and Backend Engineering teams to operationalise machine learning at scale. * Help shape the future of AI and machine learning capabilities across ARQ. ## Related Videos - [PySpark - Combining Machine Learning & Big Data](https://www.wearedevelopers.com/videos/44-pyspark-combining-machine-learning-big-data) - [Why and when should we consider Stream Processing frameworks in our solutions](https://www.wearedevelopers.com/videos/1085-why-and-when-should-we-consider-stream-processing-frameworks-in-our-solutions) - [Alibaba Big Data and Machine Learning Technology](https://www.wearedevelopers.com/videos/37-alibaba-big-data-and-machine-learning-technology) - [Detecting Money Laundering with AI](https://www.wearedevelopers.com/videos/111-detecting-money-laundering-with-ai) - [Data Analytics with Microsoft Fabric: End-to-End Use Case with Data Agents](https://www.wearedevelopers.com/videos/1547-data-analytics-with-microsoft-fabric-end-to-end-use-case-with-data-agents) - [Data Science in Retail](https://www.wearedevelopers.com/videos/586-data-science-in-retail) ## Related Articles - [Data Analyst Salary in the UK](https://www.wearedevelopers.com/magazine/278-data-analyst-salary-in-the-uk) - [Data Engineer Salary UK](https://www.wearedevelopers.com/magazine/253-data-engineer-salary-uk) - [How to Become an AI Engineer](https://www.wearedevelopers.com/magazine/331-how-to-become-an-ai-engineer) - [Jobs in Tech: The State of the European Market](https://www.wearedevelopers.com/magazine/575-jobs-in-tech-the-state-of-the-european-market) - [The Most Popular IT Jobs on the Market](https://www.wearedevelopers.com/magazine/376-the-most-popular-it-jobs-on-the-market) - [Software Engineer Salary London](https://www.wearedevelopers.com/magazine/252-software-engineer-salary-london)