- 01Analytical partner to Sales on live campaigns with eight-figure monthly budgets, plus global market trend reports for leadership and client pitches.
- 02Built 10+ self-refreshing Looker Studio reports on petabyte-scale BigQuery data, scheduled with Cloud Scheduler, replacing most heavy ad-hoc SQL.
- 03Develop forecasting models for campaign performance that Sales uses to plan budgets and find growth in new markets.
- 04Own data quality for my area: SQL tests, alerting, deduplication checks and cross-source reconciliation. Caught several silent errors that were costing money.
- 05Work with BI Developers day to day, turning Sales requests into specs and documentation and prioritizing them against dev capacity.
Mateusz Bielski I'm at my best when the data is messy and real money depends on getting it right.
Brands I've impacted
2018 — 2026
(01) Summary
Business and data analyst with 8 years in tech, the last four focused on revenue analytics. At Wirtualna Polska and RTB House I've worked on portfolios with eight-figure monthly budgets, owning the numbers behind pricing and growth decisions.
Numbers I can share.
The dashboards stay under NDA. The scale behind them doesn't.
EXPERIENCE021 C
8
years in tech, the last four in revenue analytics
DASHBOARDS2736 C
200+
dashboards and reports in Looker, Tableau, Power BI, Superset and Grafana
AUTOMATION11-4201
10h+
of manual work a day given back to teams up to the CEO
SDK WPMBLACK 6 C
~60%
higher ad revenue than competing solutions
DATA SCALEBIGQUERY
PB.
petabyte-scale data behind self-refreshing Looker Studio reporting
DOOH NETWORK2018–22
20,000+
screens in the network where I led IT
(02) Experience
Four companies.
One thread: revenue.
- 01Owned quarterly revenue targets for programmatic monetization across WP's websites and mobile apps, a portfolio in the eight figures (PLN) a month, including forecasting and pricing decisions.
- 02Took the in-app advertising SDK (iOS, Android) from first requirements to a successful pilot in WP's apps. I wrote the BPMN/UML models and dev specs, then worked with the developers through to testing, which I ran myself. Apps hit ~60% higher Ad Revenue than competing solutions, and the SDK has since grown into a multi-million revenue line across external publishers.
- 03Designed and ran hundreds of A/B tests on auction and pricing logic, the main lever for hitting revenue targets.
- 04Built 200+ dashboards and reports in Tableau, Power BI, Superset and Grafana on Hive data. Automating them gave back more than ten hours of manual work a day to teams up to the CEO.
- 05Brought AI into the team's analytics work, from Claude plugins to Python data-cleaning tools, automating a large share of routine analysis.
- 06Analyzed user behavior and identifiers to improve attribution and uncover new revenue streams.
- 01Analyzed rich-media campaigns for a boutique ad agency and ran performance tests, with some ad trafficking on the side.
- 02Owned the campaign data flow end to end, from Google Ads and GA tracking to the results I presented to clients.
- 01Led IT at one of Poland's largest digital out-of-home networks (20,000+ screens). Managed three developers and owned every technical problem across a ~20-person team.
- 02Planned the data side of Symulakra (2019), a live digital sculpture on a giant LED screen in central Warsaw, made with art studio panGenerator. I worked out which signals to capture (street traffic, mobile demographics) and how, then tested the data flow before launch.
- 03Ran software projects from cost estimate to delivery and built a pool of outsourced specialists for work beyond the team's reach.
(03) Toolkit
What I work with.
-
BI & Visualization
- BI & VisualizationPower BI
- BI & VisualizationTableau
- BI & VisualizationLooker Studio
- BI & VisualizationGoogle Looker
- BI & VisualizationSuperset
- BI & VisualizationGrafana
-
Data & Cloud
- Data & CloudGCP
- Data & CloudBigQuery
- Data & CloudPeriodic checks
- Data & CloudSQL
- Data & CloudHive
-
Monitoring
- MonitoringDatadog
- MonitoringSentry
-
Code & AI
- Code & AIPython
- Code & AIGit
- Code & AIClaude
- Code & AIQwen
- Code & AIOpenClaw
-
Delivery
- DeliveryJira
- DeliveryConfluence
- DeliveryFigma
- DeliveryExcel
- DeliveryGoogle Sheets
-
Learning
- Learningdbt
- LearningAirflow
Methods & practices
- A/B testing
- Forecasting
- Revenue & pricing analytics
- Data quality: testing, validation, reconciliation
- Data warehouses & lakes
- Pipelines
- Data governance
- CTEs & query cost optimization
- Requirements & specifications
- BPMN
- UML
(04) Education
Military University of Technology, Warsaw
Engineer's degree (BEng), Logistics, 2018
Thesis: "Profiling customers based on their online behavior"
(05) Soft skills
- Presenting to leadership and clients
- Stakeholder management
- End-to-end project ownership
- Problem solving under pressure
- Cross-team collaboration
(06) Languages
Polish native
English C1