04.2024 — present
Data Engineer
EY
- Optimizing ETL processes
- SQL & Python development
- Airflow orchestration
- System architecture design
- OpenSearch and data backends for internal tools
Portfolio
JakubJarosiński
I am a
Data Engineering, AI Engineering & cool stuff development.
About
Hello there
- Full name
- Jakub Jarosiński
Welcome to my website. I am a data engineer and software developer with experience from startups to large international organizations. At EY I build reliable data pipelines and backend services that keep internal products running. I also lead technical development at the commodity trading startup harvium.pl.
Outside of work I like digging into cloud platforms, web development, solid engineering practices, and finance.
Tech I've used
- Linux
- Python
- TypeScript
- Java
- Hadoop
- Spark
- Databricks
- Airflow
- React
- Node
- SQL
- PostgreSQL
- Kafka
- RabbitMQ
- LLMs
- Langchain
- MySQL
- MongoDB
- Docker
- Azure
- AWS
Resume
Experience & education
Data engineering roles, software delivery, and a finance-heavy early career.
Work experience
08.2024 — 03.2025
Data Engineer
Uniqa Insurance Group· Warsaw
- Data lake work: Hadoop, Spark, Airflow, YARN, Hue, PostgreSQL, Oracle
- Python with Spark, Pandas, PySpark
- Developing pipelines in Airflow
09.2022 — 07.2024
Data Engineer
Polkomtel· Warsaw
- Data analysis and operational reporting
- ETL optimization, SQL, Python, Java
- Spark, NiFi, Kafka, Airflow
- System architecture, Agile delivery
- Power BI, Tableau
09.2021 — 04.2022
Data Analyst (Finance)
Franklin Templeton Investments· Poznań
- Data and financial analysis
- Python automation, SQL
- Analytics in Python, R, Jupyter
- Power BI
10.2020 — 03.2021
QA Engineer
Match-Trade Technologies· Poznań
- Database administration
- Data analysis and reporting
- Process automation in Python
- A/B testing and automated testing
- Unit testing
05.2020 — 09.2020
Equity Trader
Traderhouse.pl· Poznań
- Equity trading on NASDAQ & NSE
- Scanning for opportunities and executing strategy
- Fundamental and technical analysis
- Working with financial data and databases
02.2020 — 12.2021
Marketing Specialist / Web Developer
Dive in life· Poznań
- SEO, external contacts, marketing strategy
- REST APIs in Node.js
- Full-stack work with React and Node
- Python automation
04.2019 — 08.2019
Sales Representative
Southwestern Advantage· Nashville, TN
- Door-to-door sales and CRM
- Community relations and sales strategy
Education
2021 — 2023
Masters - Computer Science and Econometrics
Poznań University of Business & Economics · Poznań
- Scholarship for the best students (2021, 2022)
- Student exchange at the University of Ljubljana
2019 — 2021
Masters in Law
Adam Mickiewicz University · Poznań
- Completed six semesters in one year while working full time
- Droped out to pursue career and studies in Computer Science
2018 — 2021
Bachelors - Economics
Poznań University of Business & Economics · Poznań
- Member and contributor: SKN Pryzmat, SKN Profit, SKN Portfolio
- Scholarship for the best students (2020)
Portfolio
Selected projects
Experiments, products, and deep dives — some older demos preserved as static pages.
Contact
Let's build something ambitious
Email is the best way to reach me. Happy to chat about data engineering, backend and full-stack work, or new product builds.