Java Software Engineer

We are loonking for a Java Software Engineer. You will take ownership of the full software development lifecycle, from critical, high-throughput backend services to modern web and mobile user interfaces.

Missions

• Architect and implement scalable, maintainable, and decoupled microservices architectures.
• Define robust, well-documented REST APIs and JSON integration contracts to ensure seamless integration with client applications (particularly React front-ends).
• Design event-driven, asynchronous data pipelines using Apache Kafka.
• Make high-impact decisions regarding system resilience, performance optimization, and architectural modularity.
• Build enterprise-grade backend services leveraging modern Java language features (Java 17/21+) and Spring Boot 3.x.
• Deconstruct and reverse-engineer complex legacy codebases: map out dependency graphs, formulate phased migration strategies, and align technical refactoring with core business priorities.
• Design relational database schemas and optimize data access layers (JPA/SQL).
• Orchestrate long-running, distributed business workflows using engines like Temporal.
• Drive software quality and test coverage through robust unit, integration, and mocking suites (JUnit/TestNG, Mockito).
• Implement modern observability patterns (Spring Boot Actuator, distributed tracing, metrics).
• Work in an Agile/Scrum environment, participating actively in sprint ceremonies, architectural spikes, and code reviews.
• Collaborate with frontend engineers to streamline API integration and UI/UX synchronization.

Profile

Mandatory Experience & Qualifications

• 7+ years of professional software engineering experience with enterprise Java and modern Spring Boot applications (Java 17 required; Java 21+ strongly preferred).
• Solid experience designing and coding complex applications, with an emphasis on microservices, modular backend design, clean APIs, and frontend-backend integration patterns (React + Spring Boot).
• Deep expertise in REST services, JSON-based integration patterns, and event-driven architectures with Apache Kafka.
• Solid, hands-on experience working with relational databases (data modeling, query optimization).
• Strong familiarity with Agile/Scrum delivery and fluent professional English (written and spoken).

Preferred Experience & Differentiators

• Proven ability to analyze complex legacy codebases, identify dependency networks, design pragmatic migration roadmaps, and justify architectural decisions to business stakeholders.
• Experience with Spring Framework 6.x and Spring Boot 3.x (Actuator, Observability, and optional GraalVM native compilation).
• Practical experience with JPA / Hibernate.
• Strong proficiency with JUnit/TestNG and mocking frameworks like Mockito.
• Hands-on experience with the Temporal workflow orchestration engine.
• Basic understanding and working knowledge of React.

Our offer

• Working in a Great Place to Work based in Luxembourg
• Attractive salary and pretty cool benefits (meal vouchers, mobile subscription...)
• Develop your skills and ideas over a coffee, a beer or a pizza during our Neo'vations
• Evolve within a strong company culture, you'll join us for the opportunity and you'll stay because we're super cool (well according to 98% of our employees NEOFACTO Annual Survey 2024)
• Between afterworks, innovative workshops and ski weekends, there's never a dull moment when you're part of the Neo'Squad

Recruitment Process

• The pre-qualification interview with our Recruitment Manager

Technical tests

• Receipt of our salary proposal / exclusivity agreement
• Proposal of your application to the client
• Interview at the client's premises, which can be conducted either by video or in person