Senior Java Backend Developer | Spring Boot & REST APIs

Diverse Consulting Group; Polska; Hybrid; PLN 180,000 - 260,000; Full time

Benefits offered by this job

Private medical care

Co-financing for the sports card

Dedicated consultant support

Job summary

Diverse Consulting Group is seeking an experienced Backend Java Engineer to join our client teams and deliver scalable digital banking services. You will own backend design, testing, and integration while collaborating with stakeholders to translate requirements into robust technical solutions.

You bring at least 6 years of Java backend experience (JDK 21+), Spring Boot 3.5, strong testing skills (JUnit 5, WireMock), and familiarity with CI/CD and OpenAPI.

Qualifications

• Minimum 6 years of professional experience in software development with a strong focus on Java backend development.
• Extensive hands-on experience with Java (JDK 21+), Spring Boot 3.5, and familiarity with newer versions (JDK 25+, Spring Boot 4.x).
• Proficient in Git, Maven, and OpenAPI (Swagger).
• Demo familiarity with CI/CD pipelines, Jenkins and release procedures.
• Experience with unit and integration testing using JUnit 5, AssertJ, and WireMock.
• Knowledge of SQL, JDBC, Spring Template, and Hibernate ORM.
• Comfort using IntelliJ IDEA, VS Code, and API testing tools (Postman, Bruno, IntelliJ HTTP Client).
• Experience leveraging AI-assisted coding tools to improve development, testing, and automation efficiency.

Responsibilities

• Design, develop, test, and maintain backend services supporting large-scale digital banking platforms.
• Take ownership of backend testing activities within the Agile team, ensuring software quality, reliability, and performance.
• Develop and maintain unit, integration, and API tests to support continuous delivery and high-quality releases.
• Collaborate with business stakeholders to understand requirements and translate them into effective technical solutions.
• Participate in technical analysis, solution design, and architectural discussions.
• Contribute to the entire software development lifecycle, including implementation, testing, deployment, maintenance, and continuous improvement.
• Use AI-assisted development tools to improve coding efficiency, testing, and automation of routine tasks.
• Work closely with cross-functional team members to deliver secure, scalable, and customer-focused digital banking solutions.

Skills

Java backend development

Java (JDK 21+)

Spring Boot 3.5

JDK 25+

Spring Boot 4.x

Git

Maven

OpenAPI/Swagger

CI/CD pipelines

Jenkins

JUnit 5

AssertJ

WireMock

SQL/JDBC

Hibernate ORM

IntelliJ IDEA

VS Code

Postman

AI-assisted coding tools

Tools

Git

Maven

OpenAPI (Swagger)

Jenkins

JUnit 5

WireMock

SQL/JDBC

Hibernate ORM

IntelliJ IDEA

VS Code

Bruno

Postman

Job description

Diverse Consulting Group is seeking an experienced Backend Java Engineer to join our client teams and deliver scalable digital banking services. You will own backend design, testing, and integration while collaborating with stakeholders to translate requirements into robust technical solutions.

You bring at least 6 years of Java backend experience (JDK 21+), Spring Boot 3.5, strong testing skills (JUnit 5, WireMock), and familiarity with CI/CD and OpenAPI.