Java Backend Engineer

At Quento Technologies S.A., the ICT arm of the Qualco Group, we deliver comprehensive and innovative solutions across AI, Digital Engineering, Cloud, and Cybersecurity, helping businesses accelerate digital transformation. With a presence in Greece, Luxembourg, and Belgium, and backed by the expertise of the Qualco Group, we combine deep technical knowledge with strategic partnerships to support business growth.

At Quento Technologies S.A. we empower our people to innovate and lead in delivering transformative ICT solutions to our clients worldwide. \

Quento Technologies S.A. seeks a highly motivated Java Backend Engineer to to be engaged in the following projects: Player Account Management (PAM), Janus (Retail – PAM), Financial Applications (CPP, CPF, HWS, e-procurement) and TORA applications.

Your responsibilities will entail:

• Design, develop, test, and maintain high-quality Java applications and services;
• Participate in the full software development lifecycle, from requirements analysis and design through implementation and delivery;
• Develop and integrate RESTful APIs and backend services;
• Contribute to the design and evolution of scalable, reliable, and maintainable software solutions;
• Write clean, efficient, well-tested, and reusable code following development best practices;
• Troubleshoot, analyze, and resolve technical issues, ensuring application performance and stability;
• Collaborate closely with developers, architects, product teams, and other stakeholders;
• Participate in code reviews and contribute to improving development standards and engineering practices;
• Support continuous improvement by exploring new technologies, tools, and development approaches;
• Contribute to technical documentation and knowledge sharing within the team;
• Ensuring that all activities and duties are carried out in full compliance with regulatory requirements and supporting the continued implementation of the Group Anti-Bribery and Corruption Policy.

• University degree in Computer Science, Engineering, or a related field;
• Very good knowledge of Java;
• Experience in at least 3 of the following frameworks/specifications: Spring, Spring Boot, JEE/Jakarta EE, JAX-RS, JPA, JDBC;
• Experience with at least one testing framework;
• Good understanding of distributed systems;
• Good understanding of the HTTP protocol;
• Experience in designing and implementing relational database systems (Oracle / MySQL / MS SQL Server);
• Experience with message brokers such as Kafka, AMQP;
• Knowledge of RESTful API design principles;
• Strong analytical, problem-solving and organizational skills;
• Experience in version control (Git).

Nice to Have

• Good understanding of system resiliency and cloud-native architecture;
• Understanding of reactive programming;
• Knowledge of containerization (Docker);
• Some knowledge of container orchestration (Kubernetes);
• Experience with the ELK stack;
• Experience with Java build tools such as Gradle;
• Hands-on experience with agentic coding tools (e.g., Claude Code, GitHub Copilot agent mode, Cursor) across the SDLC: code generation, refactoring, test creation and code review;
• Ability to work effectively with AI coding agents: writing clear task specifications and prompts, reviewing and validating AI-generated code for correctness, security and performance, and keeping human accountability for what is merged;
• Familiarity with integrating AI-assisted workflows into team practices (CI/CD pipelines, pull-request reviews, documentation generation) while following secure-coding and data-protection guidelines.

Your Life @ Qualco Group
On top of challenging work environment, we are offering:

💸 Competitive compensation, ticket restaurant card, and annual bonus programs
💻 Cutting-edge IT equipment, mobile and data plan
🏢 Modern facilities, free coffee and beverages, indoor parking, and company bus
👨‍⚕ Private health insurance, onsite occupational doctor, and workplace counselor
🏝️ Flexible working model, hybrid benefits & home equipment benefits
🤸‍♂️ Onsite gym, wellness facilities, and ping pong room
💡 Career and talent development tools
🎓 Mentoring, coaching, personalized annual learning and development plan
🌱 Employee referral bonus, regular wellbeing, ESG and volunteering activities

Your race, gender identity and expression, age ethnicity or disability make no difference in Quento Technologies S.A. We want to attract, develop, promote, and retain the best people based only on their ability and behavior.

Disclaimer: Quento Technologies S.A. collects and processes personal data in accordance with the EU General Data Protection Regulation (GDPR). We are bound to use the information provided within your job application for recruitment purposes only and not to share these with any third parties. For more details on the processing of your personal data during the Recruitment procedure, please be informed in the Recruitment Notice, before the submission of your application.