About Sebastian
Data Scientist with 6+ years of experience building production-grade data pipelines and AI-driven automation across Big Four environments. Expert at transforming fragmented, unstructured data into high-fidelity business intelligence using Large Language Models (LLMs), Natural Language Processing (NLP), and applied Machine Learning. Proven track record of architecting solutions that eliminate operational bottlenecks, including a 15x reduction in processing time on enterprise reporting workflows.
English
Native or bilingual
Spanish
Native or bilingual
Can work on-site
Barcelona (up to 50km)
Experience
- Evolve On CData ScientistCONSULTING AND AUDITSFebruary 2026 - Today (4 months)Barcelona, Spain• • Build an LLM-driven Google Ads optimization tool for a US retail client that mines Search Term Reports to flag negative keyword candidates and surface new positive keywords from search context, replacing manual analyst review with a human-in-the-loop workflow.• • Engineer multi-stage Python pipelines for automated lead generation, combining web scraping with a locally hosted Generative AI model (Gemma 4) for real-time target assessment and personalized content generation.• • Lead the digital rebrand of Evolve On C, delivering a new firm website, brand identity, and supporting marketing assets through LLM-assisted development workflows.
- PwCSenior Associate, Forensic TechnologyCONSULTING AND AUDITSJanuary 2024 - June 2025 (1 year and 5 months)Brussels, Belgium• • Prototyped a Retrieval-Augmented Generation (RAG) solution for legal-tech eDiscovery, enabling investigators to navigate dense electronic evidence corpora through semantic search and on-demand contextual retrieval.• • Proposed and delivered an HR analytics engagement for a EU Instituion, quantifying employee uptake and behavioural patterns around workforce policies to inform future policy design.• • Designed and built a live command-center dashboard for a nuclear plant dismantling programme, integrating disparate project tracking systems into a unified real-time view with drill-down to process-level progress.
- EYSenior Consultant, Forensic Data AnalyticsCONSULTING AND AUDITSJuly 2021 - December 2023 (2 years and 5 months)Santiago, Santiago Metropolitan Region, Chile• • Built and deployed scalable Alteryx Analytics Apps that standardized data processing, reducing data analytics procedures from 45 hours to 3 hours, a 15x improvement in delivery speed.• • Architected EY Virtual, a fully customizable Microsoft Azure platform designed to deliver analytics services at enterprise scale.• • Led fraud and compliance audits for high-risk clients across holdings, gaming, insurance, and banking industries in Latin America, owning the workflow end-to-end from ERP data extraction (SAP, Oracle) through findings presentation to client leadership.• • Designed fraud analytics combining traditional red-flag rule sets with TF-IDF based lead generation to surface high priority transactions for investigative review.• • Developed a multi-threaded web scraping solution in Python to systematically quantify keyword relevance across media sources for enterprise intelligence gathering.
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Education
- MSc in Data Science for Decision MakingBarcelona School of Economics (BSE)2026
- BSc in Consumer EconomicsUniversity of Illinois at Urbana Champaign2017
Certifications
- Certified Fraud ExaminerAssociation of Fraud Examiners2022