Senior Java Developer

AIDA projektai, MB; Warszawa; Hybrid; PLN 236,000 - 289,000; Full time

Benefits offered by this job

Fully remote in Warsaw

Hybrid/remote in Vilnius

Salary negotiable

Job summary

AIDA projektai, MB is seeking a Senior Java Developer for Poland or Lithuania. You will design and implement features using Java 17–21 and Spring, ensure system reliability, and participate in architecture discussions.

The role involves AWS hosting, database work with MySQL/Hibernate, and contributing to code quality through reviews. Candidates should have 5+ years of Java experience, strong REST/microservices skills, and English communication.

Qualifications

• 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.

Responsibilities

• Design, implement, and integrate new functionality using Java 17–21 and the Spring ecosystem.
• Provide ongoing application support, troubleshoot production issues, and fix bugs.
• Manage deployment on AWS and contribute to infrastructure improvements.

Skills

Java 17-21

Spring Framework

REST & Microservices

JUnit/Mockito

AWS

MySQL/Hibernate

Gradle/Maven

Code reviews

English proficiency

Tools

Docker

Kubernetes

CI/CD (GitHub Actions/Jenkins)

Git

Job description

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)