Senior Java Developer

For our client an IT company specializing in new product development and R&D, focused on solving complex challenges in the tech industry we are looking for a Senior Java Developer based in Poland or Lithuania.

Responsibilities

• Feature development — design, implement, and integrate new functionality using Java 17–21 and the Spring ecosystem; participate in architectural discussions and code reviews;
• Application support & maintenance — provide ongoing support, troubleshoot production issues, and fix bugs to ensure high availability and stable performance;
• Cloud deployment — manage deployment, configuration, and hosting of applications on AWS infrastructure; contribute to infrastructure improvements;
• Data persistence — handle database interactions, schema design, and query optimization using MySQL and Hibernate ORM;
• Build management — use Gradle and Maven for dependency management and build automation;
• Technical ownership — contribute to architectural decisions, propose and evaluate technical solutions, and drive continuous improvement of the codebase.

Requirements

• 5+ years of commercial Java development experience;
• Deep knowledge of Java 17–21 (records, sealed classes, virtual threads, pattern matching);
• Strong command of the Spring ecosystem — Spring Boot, Spring MVC, Spring Data, Spring Security;
• Experience with relational databases (MySQL), query optimization, and Hibernate / JPA;
• Solid AWS experience — EC2, S3, RDS, IAM, CloudWatch or equivalent services;
• Proficiency with Gradle and/or Maven;
• Strong understanding of REST API design and microservices architecture;
• Experience writing clean, testable code with unit and integration tests (JUnit, Mockito);
• Confident reading and reviewing others' code; track record of meaningful code reviews;
• Upper-Intermediate English or above — comfortable in written and spoken communication with the team.

Nice to have

• Experience with Docker and container orchestration (Kubernetes / ECS);
• Familiarity with message brokers — Kafka, RabbitMQ;
• Knowledge of CI/CD pipelines (GitHub Actions, Jenkins, GitLab CI);
• Exposure to reactive programming (Project Reactor, WebFlux);
• Experience with monitoring and observability tools (Prometheus, Grafana, ELK);
• Understanding of DDD, CQRS, or event-driven architecture patterns.

Company offers:

• Warsaw (Poland) - fully remote work (B2B contract);
• Vilnius (Lithuania) - hybrid/remote (B2B or employment contract).
• Salary range: 54 000$- 66 000 EUR$ Annually (negotible)