Python Software Engineer (Data Platform)

Location: Poland We Are: RTB House is a global company that provides state-of-the-art marketing technologies for top brands and agencies worldwide. Its proprietary ad-buying engine is the first in the world to be powered entirely by Deep Learning algorithms, enabling advertisers to generate outstanding results and reach their goals at every stage of the funnel.We are looking for a Python Software Engineer to join our internal team at RTB House. You will work on the backbone of our analytics, building applications and data pipelines that handle terabytes of data daily. This position is ideal for developers passionate about data-intensive systems, performance optimization, and building reliable software that provides critical business insights. You Will: • Design, develop, and maintain the backend for web applications responsible for presenting massive-scale campaign statistics and financial data. • Build and optimize large-scale data processing jobs (ETL/ELT) that feed our core analytics and reporting systems. • Contribute to the development of internal Python libraries focused on high-performance data processing and analytics. • Write and maintain unit/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 building APIs for data-heavy applications. Desired Experience: • Solid experience in backend development for data-intensive applications with Python. • Strong proficiency with relational databases and the ability to write highly efficient, optimized SQL queries (PostgreSQL and BigQuery are key). • Understanding of RESTful and GraphQL APIs conventions, especially for serving analytical data. • Experience in asynchronous programming. • Good understanding of system design concepts in the context of Big Data (e.g., data warehousing, ETL optimization, scalability) and willingness to learn more. • Experience with writing and maintaining tests. • Problem-solving skills and the ability to work methodically through complex data challenges. • Good communication skills and ability to work in a team. 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: • Being part of a small team with a high degree of autonomy and decision-making  • Access to the latest technology in the developed solution • Opportunity to build and improve our own products, where long-term quality and reliability truly matter • Participation in one of the most interesting projects of the online industry in Poland and one of the fastest growing technology companies in Europe • Collaboration with flexible contract options (B2B or contract of mandate) Apply now!  You don't need to tick every box to apply. If you are passionate about digital marketing, send us your CV, and we'll review it.