Full Stack Developer - Java

Job Role: Java Fullstack Developer Job Location: Luxembourg Experience- 5+ Years of core development Work Type: Hybrid Note: Not open for sponsorship case. About Company: At Synechron, we believe in the power of digital to transform businesses for the better. Our global consulting firm combines creativity and innovative technology to deliver industry-leading digital solutions. Synechron’s progressive technologies and optimization strategies span end-to-end Artificial Intelligence, Consulting, Digital, Cloud & DevOps, Data, and Software Engineering, servicing an array of noteworthy financial services and technology firms. Through research and development initiatives in our FinLabs we develop solutions for modernization, from Artificial Intelligence and Blockchain to Data Science models, Digital Underwriting, mobile-first applications and more. Over the last 20+ years, our company has been honored with multiple employer awards, recognizing our commitment to our talented teams. With top clients to boast about, Synechron has a global workforce of 14,700+ and has 55 offices in 20 countries within key global markets. For more information on the company, please visit our website or LinkedIn community. Diversity, Equity, and Inclusion Diversity & Inclusion are fundamental to our culture, and Synechron is proud to be an equal opportunity workplace and an affirmative-action employer. Our Diversity, Equity, and Inclusion (DEI) initiative ‘Same Difference’ is committed to fostering an inclusive culture – promoting equality, diversity and an environment that is respectful to all. We strongly believe that a diverse workforce helps build stronger, successful businesses as a global company. We encourage applicants from across diverse backgrounds, race, ethnicities, religion, age, marital status, gender, sexual orientations, or disabilities to apply. We empower our global workforce by offering flexible workplace arrangements, mentoring, internal mobility, learning and development programs, and more. All employment decisions at Synechron are based on business needs, job requirements and individual qualifications, without regard to the applicant’s gender, gender identity, sexual orientation, race, ethnicity, disabled or veteran status, or any other characteristic protected by law. 1. Context and objectives of the engagement Client in Luxembourg has launched a strategic programme aimed at decommissioning its core banking system and modernizing its payment processing ecosystem. As part of this initiative, the beneficiary wishes to enhance its technical platform and is seeking support in designing and developing an internal application dedicated to payment flow management. In this context, the assignment will contribute to: the development of an internal application dedicated to payment flow management, including: payment controls.compliance checks.exception management.alignment with the requirements of the 2026 version of SEPA (SR2026).migration to and compliance with ISO 20022 standards. Expertise : System reliability and scalability Production stability and operational excellence Compliance with regulatory requirements and market standards. Technical Environment: The target application ecosystem is built on a modern Java technology stack and integrates with the company’s payment systems. Core Technology Stack: Languages: Java 11 / 17 / 21Frontend: Angular 19Frameworks: Spring Framework 6.x, Spring Boot 3.xBuild Tool: MavenDatabase: Oracle (Spring Data JPA / Hibernate) Security: OAuth2Spring Security 6.xAPIs & IntegrationNimbus JOSE + JWTAPIs & Integration Spring Boot Web / Spring WebFluxSpring Data RESTOpenAPI (Swagger)Runtime & Monitoring Embedded Apache TomcatSpring Boot ActuatorCode Quality & Logging SonarQube, JaCoCoLogback, SLF4JTesting JUnit 5Spring Boot TestMessaging & Integration IBM MQ (mq-jms-spring-boot-starter)Spring Integration JMSData & XML Processing JAXB, DOM4J, Jaxen, SAAJXML validation (XSD-based)Infrastructure DockerKubernetes 2. Expected Deliverables The expected deliverables are: Development Activities: - Design and develop backend components using Java / Spring Boot - Implement REST APIs and messaging flows (IBM MQ, JMS) - Ensure compliance with ISO 20022 message handling and XML standards - Write clean, maintainable, and testable code following best practices. 1. Testing and Quality Assurance: - Develop and execute unit and integration tests - Ensure high code coverage (JUnit, JaCoCo) - Contribute to non-regression and end-to-end testing - Identify and fix defects 2. Code Quality and Review: Contribute in code reviews.- Ensure compliance with coding standards and SonarQube quality gates - Contribute to continuous improvement of development practices 3. Documentation: - Produce technical documentation (architecture, design, APIs) - Maintain API documentation via OpenAPI / Swagger - Document integration flows and interfaces 4. Production Support: - Provide L3 support on the payment processing chain - Analyze and resolve production incidents - Investigate payment issues (rejections, reconciliation gaps, etc.) - Contribute to production stabilization / hardening - Perform root cause analysis and implement corrective actions 5. Collaboration and Delivery: - Contribute in Agile ceremonies (Scrum or similar) - Report progress, risks, and issues. 3. Expertise / Technologies The expertise required to deliver this engagement is listed below: AngularJava 4. Type of Service & Expected Level The expected service is: 3.2 Design - Development, Level 4