Full Stack Java Developer

Location: Brussels - Hybrid Language: EnglishEmployment Type: Employment / FreelanceDuration: 1 yearContext of missionWe are looking for a versatile developer to contribute to the full lifecycle of web application development. The role involves creating modern user interfaces, building robust back-end services, and designing the APIs that connect them. You will work on reusable components, ensure smooth integration of technical modules, and translate user needs into functional solutions. Prototyping, testing, and writing clear documentation are key parts of the job, as well as supporting deployment and participating in project meetings.Key ResponsibilitiesDevelop and maintain front-end and back-end features for web applications.Design and implement APIs and integration points.Build modular, scalable code with future reuse in mind.Integrate technology components and ensure compatibility across systems.Translate business requirements into technical solutions.Produce prototypes and proof-of-concepts.Create and execute test plans.Integrate applications with external systems and services.Prepare high-quality technical documentation.Assist teams with system deployment and configuration.Actively participate in team discussions, planning sessions, and reviews.. Required Skills & Experience·      Strong expertise in HTML5 and CSS3.·      Excellent command of Java 8/11; familiarity with Java 17+ is an advantage.·      Proven experience with the Spring ecosystem.·      Solid understanding of JavaScript and modern frameworks (Angular, jQuery, React, etc.).·      Deep knowledge of relational databases.·      Good understanding of Agile methodologies.·      Strong grasp of design principles (SOLID, IDEALS, CQRS, SAGA optional).·      Experience with interoperability technologies: REST, SOA, web services, message-driven architectures.·      Good knowledge of UML (use cases, state diagrams, activity diagrams).·      Ability to create clear, structured technical documentation.·      Confidence in delivering both business and technical presentations.·      Strong analytical and problem-solving abilities.·      Ability to adapt quickly to evolving technologies and architectures. Specific Expertise·      Advanced experience with Spring/Spring Boot 3+, Hibernate/JPA, MVC, Validation, Testing, and Spring Security.·      Hands-on experience with CI/CD practices, GIT/Bitbucket, Maven and Gradle.·      In-depth experience using Spring Boot Test, JUnit, and Mockito.·      Strong expertise in Angular and NPM.·      Extensive experience with Oracle 8+ and PL/SQL.·      Experience with Struts, JSP, Knockout.js, jQuery, and Kendo UI.·      Good knowledge of WebLogic, Tomcat, and JSON libraries (GSON, Jackson).·      Familiarity with SOAP, Spring Web Services, and REST principles.·      Experience with API gateways such as WSO2, Spring Cloud Gateway, Eureka/Zuul.·      Experience with Atlassian tools: JIRA, Confluence, Bitbucket, Bamboo.·      Understanding of modern security technologies (JWT, JWE, JWKS, OIDC, CAS).·      Knowledge of encryption, signing, and DevSecOps practices is a plus.·      Experience with Kubernetes, Docker, or AWS is an advantage.·      Familiarity with MySQL 5+ is an asset.·      Experience with ESB technologies (Apache Camel, ServiceMix, Oracle Service Bus...) is an asset.·      Knowledge of web accessibility standards (WCAG 2.0/2.1, WAI-ARIA).·      Understanding of UX best practices, including responsive/mobile-first design.·      Experience integrating with European Commission systems (ECAS/EULogin, Decide, ARES) is a plus.