Senior Java Backend Engineer – GenAI / Big Data
- Location: Warsaw, Poland
- Work Model: Hybrid – 3 days onsite per week
- Contract: 12 months UoP Contract
We are looking for a Senior Java Backend Engineer to join a Warsaw-based engineering team working on highly scalable, data-intensive applications with a growing focus on Generative AI and Agentic AI solutions.
The role is primarily focused on hands-on Java backend development, with Spring Boot and Microservices at its core. Alongside this, you will have the opportunity to work with large-scale data technologies and contribute to production-grade GenAI/LLM and agentic applications.
Key Responsibilities
- Design, develop and maintain production-grade backend applications using Java, Spring Boot and Microservices.
- Take ownership of technical solutions and make independent engineering decisions.
- Work with large-scale data processing and distributed data platforms.
- Develop and integrate GenAI/LLM-based solutions, including agentic applications and workflows.
- Collaborate with users and stakeholders to understand requirements, clarify problems and propose appropriate technical solutions.
- Contribute to the full development lifecycle, from solution design through implementation and production delivery.
- Evaluate existing technical approaches and proactively suggest improvements or alternatives.
- Work closely with other engineers across backend, data and AI areas to deliver end-to-end solutions.
Essential Skills & Experience
- Strong hands-on experience with Java development.
- Strong experience with Spring Boot and Microservices.
- Proven experience writing and delivering production-quality code.
- Experience working independently and taking ownership of technical decisions.
- Experience with large-scale data processing, distributed systems or data engineering.
- Hands-on experience with one or more of:
- Apache Spark
- Databricks
- Snowflake
- Experience building production GenAI / LLM-based applications or Agentic AI solutions.
- Experience with an LLM/AI framework such as LangChain, LangGraph or an equivalent framework.
- Strong communication skills and the ability to work directly with users/stakeholders.
Nice to Have
- Experience with RAG, AI Agents or agentic workflows.
- Python experience, particularly in the context of GenAI/LLM solutions.
- AWS or other cloud experience.
- Kubernetes / cloud-native application experience.
- Experience working with high-volume, data-intensive applications.