Java Backend Developer (Mid/Senior)

Quick Facts

• Role: Mid/Senior Java Developer

• Work style: Hybrid (1 day per week in Warsaw office)

• Focus: Backend microservices, fraud detection, and business process automation with AI-assisted development

Description

You’ll work on a long-term technology project building a modern ecosystem for handling claims and benefits. The team develops backend services, APIs, and integrations using Java, Spring Boot, and microservices, including a fraud detection system. The work targets large-scale, complex business logic with high requirements for performance, reliability, and code quality, supported by AI-assisted and agentic AI tools.

Responsibilities

• Design and develop Java backend applications using Spring Boot and microservices architecture

• Build and evolve APIs and system integrations

• Work with Apache Kafka and distributed system messaging

• Develop solutions for fraud detection and business process automation

• Collaborate on architecture design and implementation of new features

• Create unit and integration tests, participate in code reviews, and maintain high code quality

• Use AI-assisted development and agentic AI tools as part of daily development

• Collaborate with business analysts, Data Scientists, testers, and the development team in Agile/Scrum

Requirements

• Commercial experience developing in Java (Mid/Senior level)

• Strong knowledge of Spring Boot

• Strong knowledge of Spring Cloud

• Strong knowledge of Hibernate

• Practical experience with Apache Kafka

• Good knowledge of SQL and working with databases

• Experience designing and developing microservices-based systems

• Knowledge of unit and integration testing

• Understanding of OOP principles and functional programming concepts

• Familiarity with containerization

• Knowledge of resilience concepts for distributed systems and performance diagnostics

• Knowledge of BPMN and process engines

• Experience with Angular and building frontend applications

• Openness to using AI tools in the development process