Python Data Engineer

RTB House provides state-of-the-art marketing technologies powered by Deep Learning algorithms, enabling advertisers to achieve outstanding results at every stage of the funnel.

We are looking for a Python Software Engineer to join the internal team and work on the backbone of analytics, building applications and data pipelines that handle terabytes of data daily. This role is ideal for developers passionate about data-intensive systems, performance optimization, and building reliable software delivering critical business insights.

You Will:

• Design, develop, and maintain the backend for web applications presenting massive-scale campaign statistics and financial data.
• Build and optimize large-scale data processing jobs (ETL/ELT) feeding core analytics and reporting systems.
• Contribute to internal Python libraries focused on high-performance data processing and analytics.
• Write and maintain unit and integration tests to ensure data integrity and code quality.
• Identify bottlenecks and propose improvements to enhance data pipeline performance, query speed, and data accuracy.
• Collaborate with Data Analysts and Product teams to deliver new metrics and analytical capabilities.
• Apply best practices in application design, data modeling, and API development for data-heavy applications.

Desired Experience:

• Solid experience in backend development for data-intensive applications with Python.
• Strong proficiency with relational databases and highly optimized SQL queries (PostgreSQL and BigQuery).
• Understanding of RESTful and GraphQL API conventions for analytical data.
• Experience in asynchronous programming.
• Understanding of Big Data system design concepts such as data warehousing, ETL optimization, and scalability.
• Experience with writing and maintaining tests.
• Strong problem-solving and communication skills.

Selected Technologies:

• Backend: Python, FastAPI
• Databases: BigQuery, PostgreSQL
• GraphQL: Ariadne
• Messaging: Google Pub/Sub
• Data Handling & Validation: Pydantic, dataclasses
• Testing: Pytest
• Monitoring: Sentry, Prometheus, Grafana
• CI/CD: GitHub Actions
• Cloud: GCP, Kubernetes

We Offer:

• High degree of autonomy and decision-making within a small team.
• Access to the latest technologies in developed solutions.
• Opportunity to build and improve products with long-term focus on quality and reliability.
• Participation in one of the most interesting online industry projects in Poland and a fast-growing European technology company.
• Flexible contract options (B2B or contract of mandate).