Who I am

Portrait of Sergei Polianskii

About Seppl

Seppl is the independent consultancy of Sergei Polianskii, a senior data engineer and data architect based in Stockholm. For over 10 years I've designed and built cloud-native data platforms on Microsoft Fabric and Azure Databricks, working with Lakehouse and medallion architectures, Data Vault and dimensional modeling, and ETL/ELT pipelines across healthcare, the public sector, and enterprise.

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Experience

2025 — Present

Data Architect, ST1 Biogas

Leading the design of a greenfield Microsoft Fabric data platform, from Lakehouse architecture to governed, business-ready data products.

2025 — Present

Data Architect, Kommunal

Building Data Vault and dimensional models for a greenfield Fabric platform, and setting up the CI/CD practices around it.

2022 — Present

Senior Data Engineer, Aleris

Migrated the data platform to a Lakehouse architecture and built Data Vault models supporting insurance invoicing and revenue tracking for a leading Nordic healthcare provider.

2020 — 2022

Data Engineer, Praktikertjänst

Led a new Azure data warehouse for Sweden's largest private healthcare provider, automating ETL/ELT across 50+ daily data sources.

2019 — 2020

Data Engineer, PwC

Built data models and pipelines for financial services clients on Azure, plus executive Power BI reporting.

2017 — 2020

Data Engineer, Trafikförvaltningen

Built a real-time big data solution for Stockholm's public transport network.

2014 — 2017

BI Consultant, Kentor

Delivered enterprise data warehouses and master data management solutions across multiple client companies.

2004 — 2014

Web Developer → Database Developer → Team Lead, National Satellite Company

Progressed from web development to leading a software team delivering core IT and BI systems for Russia's largest satellite TV provider, Saint Petersburg.

Certifications

Education

Bachelor of Mathematics, Saint Petersburg State University (1998 — 2004)

Languages