Senior Data Engineer w Warszawa, Polska

MWDN is an international recruitment and outstaffing company with 23+ years of experience connecting exceptional tech talent with leading companies across Israel, the USA, Great Britain, and Western Europe. In this role, MWDN acts as the recruitment partner, and the selected candidate will work directly with the client’s team on their product in an international environment.

Here’s what you can expect when you join MWDN:

• Security: We carefully vet our clients to minimize risks and ensure reliability and timely payments—no fraud or unpleasant surprises.
• Career support: If a project isn’t the right fit, we support you and actively help find new opportunities that match your skills and career goals.
• Legal assistance: We provide guidance on legal matters, including opening and managing your independent contractor or sole proprietorship status, taxes, and related processes.
• Professional development: We offer English courses and professional growth opportunities, as well as team-building events.

Why choose us? MWDN is ranked among the top 5 IT employers in our region according to DOU. We take pride in our transparency and strong commitment to our team. Curious to learn more? See what our employees say about working with us on  DOU .

Domain: Data Infrastructure & Analytics / AdTech

Client Location: Israel

Company size: 11–50

Founded in: 2025

A fast‑growing ad‑tech company building next‑generation programmatic advertising infrastructure. The team focuses on high‑performance systems, real‑time bidding, and AI‑driven optimization. The environment is fast, product‑focused, and highly collaborative, with strong engineering leadership and a culture of ownership.

We're looking for a Senior Data Engineer to join our engineering team and help shape the future of programmatic advertising. You'll architect and build high‑performance systems that process millions of ad transactions in real time, while leveraging cutting‑edge AI technologies to optimize outcomes for our partners.

This role sits at the intersection of ad‑tech and AI, working with massive‑scale systems and sub‑millisecond latency requirements. You’ll own the full development lifecycle from architecture to deployment, collaborating with a modern, high‑performing engineering team.

• 5+ years of professional data engineering experience
• 2+ years working with programmatic advertising or ad-tech data
• Strong proficiency in Python and SQL
• Experience with streaming data platforms (Kafka, Kinesis, Pub/Sub)
• Hands-on experience with data warehouses (BigQuery, Snowflake, Redshift, ClickHouse)
• Experience with batch processing frameworks (Spark, dbt, Airflow)
• Understanding of ad-tech data structures: bid requests, impressions, OpenRTB schemas, log-level data
• Experience with cloud platforms (AWS, GCP) and infrastructure-as-code

Ad-Tech Stack:

Data Sources (Familiarity Required):

• SSP reporting APIs and log-level data (Magnite, PubMatic, Index Exchange, Xandr)
• Google Ad Manager (GAM) reporting, Data Transfer files, and BigQuery exports
• Prebid Analytics adapters and bid stream data
• Mobile measurement platforms (AppsFlyer, Adjust, Kochava) for app monetization data
• Real-time bidding (RTB) log files and auction data

Data Models & Metrics:

• Revenue metrics: CPM, eCPM, RPM, fill rate, win rate, bid density
• Auction analytics: bid landscape, floor optimization, timeout analysis
• Demand partner performance: SSP/bidder scoring, latency analysis
• Supply chain data: https://jobeax.com/link/Bk2wUHBwBB606M11 validation, https://jobeax.com/link/PaviMM2ITWk0IB1o mapping, SPO analysis

Nice to Have

• Experience with ML feature engineering for bid optimization or yield prediction
• Background in building data products for publisher-side monetization
• Familiarity with privacy-preserving data techniques (differential privacy, clean rooms)
• Experience with CTV/OTT advertising data and video ad metrics
• Knowledge of identity resolution and cross-device data challenges

• Design and build scalable data pipelines for processing bid stream, impression, and revenue data from programmatic sources
• Ingest and normalize data from multiple SSPs, DSPs, ad servers (GAM), and third-party reporting APIs
• Build real-time and batch processing systems for auction analytics, win rate analysis, and bid landscape modeling
• Develop ETL/ELT workflows to transform raw programmatic data into analytics-read datasets
• Create data models for yield optimization, floor price analysis, and demand partner performance
• Build and maintain data warehouses and lakes optimized for ad-tech query patterns
• Implement data quality monitoring, validation, and anomaly detection for programmatic data streams
• Support BI and analytics teams with clean, documented, and performant data infrastructure
• Ensure data privacy compliance (GDPR, CCPA) in data collection, storage, and processing

• People-first management with minimal bureaucracy
• A friendly company culture, proven by employees who choose to return
• Flexible working hours
• 29 days of PTO (18 working days per year pluse all national holidays)
• 10 paid sick days
• Full financial and legal support for independent contractors
• Free English classes, with native speakers or Ukrainian teachers
• Dedicated HR support

✅ Intro call with a Recruiter — ✅ Tech interview — ✅ Home assignment — ✅ Final client interview— ✅ Offer

REQUIREMENTS