Senior Java Backend Developer

We are seeking an experienced Senior Java EE Developer to join our consulting team for a high-impact modernization and upgrade project within a mission-critical banking system.

The role focuses on upgrading and stabilizing an existing Java Enterprise (Java EE / JEE) application, including components based on Enterprise JavaBeans (EJB), application servers, and persistence layers.

The ideal candidate has hands-on experience with Java EE technologies, including EJB, and has actively participated in technical upgrades or migrations of large-scale enterprise systems, rather than only greenfield development.

Remote work within Poland, with the option to work from CGI offices in multiple cities.

Job responsibilities:

Perform a technical upgrade of the banking application, including:

• Analyzing the existing application architecture, dependencies, and configurations to identify upgrade impacts.
• Refactoring and optimizing code as needed to ensure compatibility with new versions.
• Collaborating with architects, QA, and DevOps teams to ensure smooth integration, testing, and deployment.
• Documenting upgrade steps, migration guidelines, and technical challenges/resolutions.
• Supporting knowledge transfer and providing guidance to client technical teams post-upgrade.

Required qualifications to be successful in this role:

• 5+ years of Java development experience in enterprise environments.
• Hands-on experience with Java EE / Jakarta EE technologies, including Enterprise JavaBeans (EJB) and application servers (e.g., JBoss/WildFly, WebLogic, WebSphere).
• Proven experience with application upgrade/migration projects in large-scale, mission-critical systems.
• Solid understanding of enterprise integration patterns, deployment pipelines, and performance tuning.
• Strong problem-solving and debugging skills.
• Experience in the banking or financial services industry is a plus.
• Flexibility to work until 1:00 PM ET / 7:00 PM CET occasionally and as needed.

Nice to Have Skills:

• Familiarity with JPA specifications and persistence migration best practices.
• Exposure to containerization and cloud platforms (e.g., OpenShift, Kubernetes, AWS, Azure).
• Knowledge of CI/CD pipelines and modern DevOps practices.
• Strong communication and consulting skills for client-facing interactions.
• Experience with AI tools.
• Knowledge of database performance.
• Knowledge of security.
• Experience with website load/performance tools and best practices related to performance parameters and metrics.
• Java upgrade experience.
• Experience with monolith decomposition into microservices.
• Architecture skills.

What we offer:

• Healthcare / Medicover paid by CGI with a free dental package
• Share purchase plan co-financed by CGI, with the possibility of cashing at any time
• Sport card
• Employee psychological support program
• Annual bonus plan, depending on the annual financial results
• Rewarded referral program, minimum PLN 6k for recommendation
• Be Consultant program, thanks to which you have the opportunity to strengthen your competences
• Mentoring program
• Possibility of accounting for creative work (author's tax-deductible costs)
• Attractive training program - Brown Bags, hackathons and knowledge sharing
• Additional insurance - life, accident and serious illness insurance
• Additional childbirth insurance