Wathek Mezni

Senior Data & Ai Consultant @EY

Supported major clients (BPCE, Renault, Desjardins, Suncorp, AG assurance) in the modernization of their data and AI ecosystems, with a focus on migrating legacy SAS environments towards Python, PySpark, Dataiku, and Databricks cloud-native solutions.Designed and deployed large-scale data pipelines and scoring workflows in Databricks and BigQuery, processing hundreds of millions of records monthly with automated monitoring, lineage, and performance tracking.Led technical assessments and refactoring of SAS/SQL workflows on Teradata and SSMS, ensuring optimized performance, cost reduction, and seamless integration with BI tools such as PowerBI, Looker, and Spotfire.Acted as a subject matter expert in risk modeling (PD, LGD, IFRS 17), delivering robust predictive models validated through backtesting, stress testing, and transition analysis, and driving model deployment into production.Developed a GenAI-powered SAS-to-X migration platform leveraging LLMs, RAG, LangChain, and LangGraph, while enabling explainability and documentation through automated lineage and visualization frameworks.Delivered interactive visualizations and governance dashboards for executive stakeholders, strengthening risk oversight and audit compliance across multiple projects.Collaborated with cross-functional teams of data engineers, actuaries, and business stakeholders in agile environments, providing technical leadership, coaching, and continuous improvement of delivery processes.Conducted research and prototyping on Generative AI, NLP, and optimization methods (OR-Tools) to extend EY’s data capabilities and advise clients on emerging technologies.