Python Tech Lead (Fintech)

TL;DR

Python Tech Lead (Fintech): Leading the backend engineering for a nationally trusted mobile payment platform with an accent on high-concurrency and real-time processing. Focus on designing scalable APIs, migrating legacy systems to modern Python architecture, and mentoring a small engineering team.

Location: Hybrid: Must be able to work 3 days/week onsite in Warsaw, Poland

Company

A leading mobile payments platform serving millions of users, currently migrating from legacy infrastructure to a scalable Python-based architecture with real-time processing and AI-driven components.

What you will do

• Lead the design and architecture of scalable backend services using Python and FastAPI.
• Define technical standards and best practices for RESTful and GraphQL APIs.
• Guide the team in building real-time features using asynchronous programming (asyncio).
• Manage SQL and NoSQL database usage for processing large volumes of transactional data.
• Oversee CI/CD pipelines using GitHub Actions, Docker, and Kubernetes.
• Mentor engineers through code reviews and technical guidance.

Requirements

• 7+ years of backend engineering experience, including 2+ years in a technical leadership role.
• Expert-level Python skills and deep experience with FastAPI or Flask.
• Proven track record architecting real-time communication solutions such as WebSockets.
• Strong experience with cloud platforms (AWS, GCP, or Azure) and serverless architecture.
• Proficiency with containerization (Docker) and CI/CD pipeline design.
• Must be based in or able to work 3 days/week onsite in Warsaw, Poland

Nice to have

• Experience leading migrations from Java-based systems to Python.
• Familiarity with mobile analytics tools like Firebase or Mixpanel.
• Experience collaborating with mobile developers (Native, React Native, or Flutter).
• Knowledge of monitoring tools such as Prometheus, Sentry, or ELK.