NSI - Senior Java Developer

We are currently looking for a Senior Java Developer for one of our client in the financial sector. As part of a major modernization initiative, our client is undertaking the complete redevelopment of an existing legacy application currently built in Delphi. The objective is to deliver a modern, scalable, and cloud-ready solution and successfully deploy it into production. Your main responsibilities as a Consultant Lead the technical implementation of a complete rewrite of an existing business-critical application. Design, develop, and maintain robust backend services and modern user interfaces. Make technical decisions aligned with the approved architecture and project objectives. Ensure architectural consistency across all developments. Act as a technical lead and coordinator for a team of two developers. Review code and promote development best practices. Ensure compliance with internal security standards, guidelines, and documentation. Collaborate closely with business and technical stakeholders. Define, assign, and track development activities using the project's task management tools. Support testing, integration, deployment, and production readiness activities. Contribute to continuous improvement initiatives within the project team. Work effectively in an Agile delivery environment. Your profile Minimum 10 years of professional software development experience. Proven experience as a Senior Developer, Lead Developer or Technical Lead. Strong sense of autonomy. Fluent English is mandatory (minimum level C1), French is an asset Excellent verbal and written communication skills. Technical skills : Strong expertise in Java or Kotlin, Spring Boot and the JVM ecosystem. Experience designing and developing RESTful APIs. Good knowledge of relational databases (PostgreSQL is a plus). Familiarity with messaging technologies such as Kafka. Proficiency in React ideally Experience with GIT/GitHub, Docker, and OpenShift. Familiarity with build tools such as Maven or Gradle. Experience working in cloud-based environments. Experience working in Agile teams and using task management tools. Nice to have: Experience with Kotlin Coroutines Experience with functional programming Experience with reactive frameworks such as Spring Webflux If at the end of the recruitment process, your application is successful, you will be required to provide an extract from your criminal record in accordance with the requirements related to our PSF status. What is offered A dynamic and innovative work environment Training programs and ongoing support Personalized and individual career development with a dedicated point of contact A wide variety of assignments thanks to a rich and diverse client portfolio An attractive salary package aligned with your skills and experience Additional fringe benefits Regular events to get together and share great moments as a team Take the opportunity to join the "NSI family," where human values remain at the heart of our priorities As a signatory of the diversity charter, this position is open to everyone, without distinction of origin, nationality, gender, age, disability, religion, or sexual orientation. Since 2017, NSI Luxembourg PSF has been operating as a provider of high value-added IT services (Agile application development, ERP, cloud infrastructure, support, AI, etc.) for clients in both the private and public sectors. We offer a flexible approach combining consultancy services and fixed-price projects, enabling us to accurately address each client's specific challenges.