Sébastien Jeanfavre

Sébastien Jeanfavre

Data Engineer @ Romande Energie SA · Switzerland

Developed the sweep join technique for data vault bridge tables · MLOps platform in production at a Swiss energy utility

Experience

Romande Energie SA
Data Engineer → Data Architect · Promoted May 2026
2022 – present
  • Designed the sweep join method for data vault bridge tables — enabling efficient and cost-effective time-interval joins across 10+ core tables consumed by 50+ analysts, critical machine learning algorithms and operational systems
  • Co-leading adoption of dbt across the analytics platform with a team of data architects, standardising transformations across the full data warehouse
  • Delivered end-to-end pipelines covering ingestion, dimensional and data vault modelling, and QlikSense reporting in a Snowflake / GitLab CI/CD environment
  • Built and operates the MLOps pipeline for energy demand forecasting: 7 scikit-learn models in production, daily retraining, 15-min inference intervals — delivering material cost savings by reducing energy imbalance on the grid
Swiss Triathlon Analytics Platform
Independent Project
2025
  • Built and sold a race analytics platform to the Swiss Triathlon Federation covering 140,000+ athletes and 40+ years of official race results — primary use case: automated talent detection across age categories and disciplines
  • Designed a Snowflake data mart (4 dimensions, 3 facts); applied AI extraction to convert unstructured race notes into structured information
  • Delivered the end-to-end analytics layer: Snowflake to Power BI integration consumed daily by the federation's sports physiologist

Skills

Data Modeling

Data Vault Dimensional Modeling dbt

Platform & Orchestration

Snowflake Airflow GitLab CI/CD

SQL & Python

SQL Python pandas numpy PyTorch scikit-learn

Visualisation

QlikSense Streamlit

Education

MSc Electrical Engineering — Data Science specialisation
EPFL, École Polytechnique Fédérale de Lausanne
2020 – 2023
  • Deep learning of Koopman operator for non-linear dynamical systems (GNN + Koopman theory)
  • Data-driven distributed control of microgrids via deep reinforcement learning
BSc Electrical Engineering
EPFL, École Polytechnique Fédérale de Lausanne
2016 – 2020
incl. Erasmus at Karlsruhe Institut für Technologie (KIT), Germany

Continuing Education & Certifications

Snowflake SnowPro Core Certified
Snowflake
Analytics Engineering Bootcamp Capstone 100%
DataExpert.io · Feb 2026 · Airflow · dbt · Snowflake · Apache Iceberg · CDC · Data Modeling
Languages
French (native) · English C1 · German B2

Writing

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