Senior Data Scientist

📋 Description

• • Own the end-to-end lifecycle of cutting-edge AI/ML models that protect Trustly’s global payment network from fraud, credit, and operational risk. You will design, train, validate, and continuously improve models that process millions of transactions in real time, directly influencing the safety and profitability of our products.
• • Translate complex risk questions into rigorous data-science problems. From exploratory data analysis in raw banking and transactional data to deploying gradient-boosted trees, graph neural networks, or transformer architectures, you will decide which techniques best solve each challenge and explain your choices to non-technical stakeholders.
• • Drive measurable business impact by linking model outputs to KPIs such as fraud-loss rates, authorization rates, and customer friction. You will run A/B and champion-challenger experiments, quantify uplift, and present concise recommendations that shape product roadmaps and executive-level strategy.
• • Partner daily with ML Engineers and MLOps to productionize models in Trustly’s decision engine. You will write clean, version-controlled Python and PySpark code, define feature stores, and build automated retraining pipelines that guarantee model freshness and regulatory compliance.
• • Engineer high-value features from vast, messy, and privacy-sensitive data sources including open-banking APIs, device telemetry, merchant metadata, and behavioral signals. You will design scalable transformations in SQL and Spark, ensuring features are both predictive and explainable.
• • Craft data-driven rule-based strategies that complement machine-learning scores. You will combine statistical thresholds, velocity checks, and consortium data to create layered defenses that adapt faster than fraud patterns evolve.
• • Monitor post-deployment performance through dashboards and anomaly-detection systems. When drift, degradation, or new attack vectors appear, you will diagnose root causes, retrain or recalibrate models, and communicate mitigation plans within hours—not days.
• • Contribute to the long-term vision of Trustly’s risk infrastructure. You will evaluate new data vendors, cloud services, and open-source libraries; prototype improvements; and champion best practices in testing, documentation, and ethical AI across the Americas Risk team.
• • Mentor junior data scientists and analysts, reviewing code, sharing domain knowledge, and fostering a culture of experimentation, curiosity, and psychological safety.
• • Represent Trustly externally by publishing whitepapers, speaking at meetups, and collaborating with industry partners to advance the state of open-banking risk management.