Java Backend Engineer

Qualco Group; Ohio; Hybrid; USD 90,000 - 130,000; Full time

Benefits offered by this job

Competitive compensation

Hybrid working model

Private health insurance

Onsite gym and facilities

Learning and development programs

Job summary

Quento Technologies S.A., the ICT arm of the Qualco Group, is hiring a Java Backend Engineer to design, develop and maintain high-quality Java applications and services. You will work on PAM, Janus, CPP/CPF/HWS and TORA applications, crafting RESTful APIs and backend components within a collaborative team.

You'll participate in the full SDLC, write clean and well-tested code, ensure performance, and contribute to documentation while aligning with regulatory requirements and the Group's

Qualifications

• University degree in Computer Science, Engineering, or a related field.
• Very good knowledge of Java.
• Experience with Spring, Spring Boot, JEE/Jakarta EE, JAX-RS, JPA or JDBC.
• Experience with at least one testing framework.
• Good understanding of distributed systems.
• Good understanding of the HTTP protocol.
• Experience with relational databases (Oracle/MySQL/MS SQL Server).
• Experience with Kafka or AMQP.

Responsibilities

• Design, develop, test, and maintain high-quality Java applications and services.
• Participate in the full software development lifecycle from requirements to delivery.
• Develop and integrate RESTful APIs and backend services.
• Contribute to scalable, reliable, and maintainable software solutions.
• Write clean, well-tested, and reusable code; follow best practices.
• Troubleshoot and resolve technical issues to ensure performance and stability.
• Collaborate with developers, architects, product teams and stakeholders.
• Participate in code reviews and improve development standards and practices.
• Support continuous improvement by adopting new technologies and approaches.
• Contribute to technical documentation and knowledge sharing.
• Ensure all activities comply with regulatory requirements and Group policies.

Skills

Java

Spring

RESTful APIs

Distributed systems

Git

SQL

Education

University degree in Computer Science or Engineering

Tools

Kafka

Docker

Kubernetes

Gradle

JDBC

JPA

Job description

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. \

Java Backend Engineer

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 @ QualcoGroup

• 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 Recruitment Notice, before the submission of your application.