Senior Java Developer

Quick Facts

• Role: Senior Java Developer

• Engagement period: 01.12.2026 – 31.03.2028 (with possible extension)

• Work model: Hybrid (1 day/week in Warsaw office; 4 days remote)

• Rate: 120–150 PLN/h net (B2B)

• Employment: Full-time (1 FTE)

• Language: English (minimum B2)

Description

You will join a long-term project focused on building and evolving robust, distributed backend systems. The role combines deep Java/Spring expertise with Domain-Driven Design, asynchronous messaging via Apache Kafka, and process orchestration using BPMN process engines. You will also leverage AI tools throughout the SDLC to accelerate coding, testing, and analysis.

Responsibilities

• Design, develop, and maintain scalable, highly resilient distributed systems using Java/Spring.

• Model business domains using Domain-Driven Design, OOP, and functional programming approaches.

• Implement asynchronous communication with Apache Kafka and orchestrate processes with BPMN engines.

• Ensure high code quality with comprehensive unit and integration tests (JUnit/TestNG/Spock, Testcontainers, WireMock).

• Diagnose, profile, and optimize application and SQL query performance.

• Actively use AI tools in the software development lifecycle (SDLC) to speed up code creation, testing, and analysis.

Requirements

• 5+ years of commercial Java experience.

• 5+ years with the Spring ecosystem: Spring, Hibernate, Spring Boot, Spring Cloud.

• 5+ years working with relational databases and SQL.

• Practical knowledge of Apache Kafka, DDD, OOP, functional programming, and resilience patterns for distributed systems.

• Proficiency in unit/integration testing with JUnit/TestNG/Spock, including Testcontainers and WireMock.

• Experience with containers and familiarity with BPMN/process engines.

• Ability to diagnose and optimize performance of production systems and database queries; practical use of AI in SDLC.

• English at least B2.

Benefits

• Long-term engagement with possible extension (01.12.2026 – 31.03.2028).

• Hybrid work model: 1 day/week in Warsaw office, the rest remote.

• B2B net rate: 120–150 PLN/h.

• Full-time commitment (1 FTE).