Full Stack Developer

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 seeks a highly motivated and experienced Full Stack Developer.

Responsibilities:

• Java Development:
• • Upgrading from Java 8 to Java 17 or a higher version;
• Developing vendor-agnostic portable applications;
• Spring Boot:
• • Developing back-end applications;
• Integrating Spring Boot applications with external services;
• Deploying Spring Boot applications on Apache Tomcat;
• API Development:
• • Developing OPENAPI-compliant Java-based REST APIs, and integrating with existing RESTful services;
• Designing and implementing APIs beyond traditional REST, including query-based (e.g. GraphQL, SPARQL) and asynchronous interaction patterns;
• Credential Management:
• • Securing applications and using secrets management tools like Hashicorp Vault;
• Refactoring code to retrieve secrets securely from an external tool;
• Dependency Management:
• • Using Maven to manage Java project dependencies;
• Database Integration:
• • Working with Oracle databases and PostgreSQL, including data migration strategies;
• Querying and updating relational databases (Oracle, PostgreSQL);
• Containerization:
• • Containerizing applications with Docker, ideally with solutions compatible with cloud-agnostic environments;
• Messaging Platforms:
• • Integrating with Message Broker message streams (e.g. Kafka) used in distributed event systems and asynchronous architectures;
• Manage and define versioned data schemas in distributed events context;
• Continuous Integration/Continuous Deployment (CI/CD):
• • Following CI/CD practices for automated testing, integration, and deployment;
• Using GIT code repositories and delivery processes;
• Licensing and Compliance:
• • Working with licensing and compliance aspects and constraints of integrated components and dependencies;
• Framework Refactoring:
• • Refactoring applications from WebLogic to Tomcat;
• Testing and Validation:
• • Testing and validation of application changes;
• Front-end testing with tools such as Mocha, Jest, Jmeter,or Cypress;
• Back-end testing with tools such as JUnit, Mockito, Postman, and Testcontainers;
• Documenting and Communication:
• • Documenting code and system configurations;
• Communication and collaboration with other teams and stakeholders;
• Providing modern, developer-friendly API documentation that includes an interactive sandbox, clear integration examples, and structured tagging based on current best practices;
• Frontend Development:
• • Using modern JavaScript frameworks, specifically Angular and potentially eUI;
• Proficient use of HTML, CSS3, responsive and accessible design principles;
• Working with frontend build tools like Webpack or Vite;
• Cloud Platforms & Monitoring:
• • Development and integration of AWS, Azure, or GCP;
• Implementing services using SaaS and CaaS hosting;
• Integrating monitoring and logging tools such such as the ELK stack;
• Monitoring data-flows and behaviours of event-based or asynchronous systems;
• Agile & Collaboration:
• • Working in Agile/Scrum environments;
• Using tools like Jira, Confluence, Sharepoint and Teams for team collaboration.

Requirements

• University degree in Information Technology or Computer Science or any related field;
• 8 years of experience in Java 8 and higher;
• 1 year of experience in Upgrading from Java 8 to recent versions (17+);
• 3 years of experience in Design and development of vendor-neutral, cloud-portable applications using open standards;
• 2 years of experience in Spring Boot framework for developing back-end applications, including configuration and operation on Apache Tomcat;
• 1 year of experience in Dependency management with Maven;
• 5 years of experience in Developing and integrating OPENAPI-compliant RESTful APIs;
• 1 year of experience in GraphQL;
• 1 year of experience in WSO2 API Gateway or similar;
• 2 years of experience in securing applications under security standards (SSDF, NIST 800-53, etc.);
• 2 years of experience in using secrets management tools like Hashicorp Vault;
• 4 years of experience in Oracle RDBMS;
• 4 years of experience in PostgreSQL RDBMS;
• 1 year of experience in Database migration;
• 1 year of experience in Integrating and configuring databases with Liquibase or similar;
• 6 months of experience with linked data approaches and related semantic or graph-based technologies, including modelling, querying, and integration;
• 3 years of experience in Oracle PL/SQL;
• 5 years of experience in XML, HTML as data formats;
• 4 years of experience in JSON;
• 2 years of experience in developing containerized applications (Docker);
• 1 year of experience in Cloud-agnostic environments;
• 2.5 years of experience with Kubernetes;
• 3 years of experience with message Brokers for asynchronous event-driven processing;
• 1 year of experience in centralized management of data schemas in asynchronous message or event streams (e.g. Schema Registry);
• 1 year of experience in monitoring and troubleshooting Kafka-based data flows and consumer performance;
• 2 years of experience with CI/CD practices for automated testing, integration, and deployment;
• 1 year of experience with GIT code repositories and delivery processes;
• 1 year of experience with managing licensing and compliance aspects of integrated components and dependencies;
• 1 year of experience with migrating applications from WebLogic to Tomcat (or equivalent Java EE to Spring Boot migration);
• 5 years of experience with Angular;
• 5 years of experience with Web development with HTML, CSS3;
• 5 years of experience with Responsive and accessible design;
• 5 years of experience with Frontend build tools like Webpack or Vite or similar;
• 4 years of experience with Backend testing tools such as JUnit, Mockito, Postman, and Testcontainers, or similar;
• 3 years of experience with Frontend testing tools like Mocha, Jest, Jmeter, Cypress, or similar;
• 3 years of experience with Cloud development in environments such as AWS, Azure, or GCP;
• 3 years of experience with SaaS and CaaS hosting services;
• 3 years of experience with monitoring and logging tools such such as the ELK Stack;
• 5 years of experience with Agile/Scrum environments;
• 5 years of experience with Atlassian suite (Jira, Confluence, etc.);
• 1 year of experience with Microsoft Sharepoint and Teams for team collaboration;
• 5 years of experience with documenting code and configuration;
• 3 years of experience with writing analysis documents;
• 3 years of experience with writing installation instructions and other technical guides;
• 3 years of experience with providing API documentation and descriptions based on industry best practices;
• Excellent knowledge of the English language.

Benefits

This role is an on - site opportunity in Luxembourg.

CV submitted in English.

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

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