Senior Back End Developer

Location: Kraków, Hybrid 3days/office OR remote

Employment type: permanent - UoP

Salary: up 30000zł/month

Senior Backend Engineer – Service Modernisation & AI Enablement

You’ll join a small, senior team working hands-on to modernise critical backend services and improve delivery speed. The role is highly practical, focused on shipping production-ready solutions and using AI as an accelerator.

What You’ll Do

• Modernise legacy Java services using proven migration patterns
• Analyse existing codebases, dependencies, and APIs, leveraging AI tools where helpful
• Design and deliver scalable, reliable microservices with strong test coverage and documentation
• Improve performance, reliability, and API responsiveness with measurable results
• Build and enhance developer tooling, CI/CD pipelines, and automation (including AI-assisted workflows)
• Collaborate closely with platform teams to ensure smooth handover and long-term ownership
• Share best practices and mentor teams

What You Bring

• 8+ years of backend engineering experience, strong in Java and microservices
• Proven experience modernising production systems at scale
• Solid API design and distributed systems knowledge
• Hands-on mindset: you write code, not just diagrams
• Experience using modern AI developer tools (e.g. Copilot, LLM-based refactoring/testing tools)
• Pragmatic, delivery-focused approach with strong collaboration skills

If you enjoy building products end-to-end—from models to production—we’d love to hear from you.