Backend Python Developer

Location: Poland We Are: RTB House is a next-generation performance demand-side platform (DSP) that uses proprietary Deep Learning AI algorithms to help brands grow. The company is the market leader in driving performance using Deep Learning across the entire purchase funnel. Founded in 2012 and now operating in 90+ markets, RTB House has always been private-by-design. It embraces first-party advertising and a relentless approach to innovation. RTB House offers end-to-end Deep Learning-powered AdTech products and solutions to maximize conversion, drive new customer acquisition, create engagement, and fuel long-term demand for a global base of clients. In 2026, RTB House launched rtb.com, a self-service platform specifically designed to allow small and medium-sized businesses and agencies to deploy auto-built creatives and maximize performance on any budget. We are looking for a Python Software Engineer to join our internal team at RTB House. You will work on applications and tools that directly support our real-time bidding business, collaborating with experienced engineers and product teams. This position is ideal for developers who want to grow their skills, solve real-world problems, and build reliable software that makes a visible difference. You Will: • Design, develop, and maintain internal web applications responsible for ad campaigns management, e.g. configuration, monitoring, automation • Implement jobs and processes to integrate internal services • Contribute to the development of internal Python libraries and shared frameworks • Write and maintain unit/integration tests to ensure code quality and reliability • Identify issues and propose improvements to enhance performance, scalability, and stability • Collaborate with cross-functional teams to deliver new features and improve existing workflows • Apply best practices in application design, databases, and APIs Desired Experience: • Solid experience in backend development with Python • Familiarity with relational databases and ability to write efficient SQL queries (PostgreSQL, BigQuery is a plus) • Understanding of RESTful and GraphQL APIs conventions and best practices • Experience in asynchronous programming • Good understanding of system design concepts (e.g. scalability, caching, reliability) and willingness to learn more • Experience with writing and maintaining tests • Problem-solving skills and the ability to work methodically through technical challenges • Good communication skills and ability to work in a team • Fluency in English Selected Technologies: • Backend: Python, FastAPI • Databases: PostgreSQL, BigQuery • 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.