Full Stack Engineer

We are seeking a highly skilled Senior Fullstack Developer to join our client’s team in Brussels. You’ll own end-to-end development of large-scale applications, spanning back-end Java services and a modern React front-end. You’ll collaborate with product owners, architects, and cross-functional teams to design, implement, optimize, and deploy high-performance software.What you’ll doDesign and develop high-performance, scalable applications using Java, Maven, and frameworks such as Quarkus or Spring.Architect and optimize MongoDB and PostgreSQL schemas, queries, and indexing to ensure low latency and high throughput.Build and scale microservices and event-driven systems using Kafka; integrate with the ELK stack for logging, monitoring, and troubleshooting.Identify bottlenecks and lead performance optimization efforts across code and database layers; implement profiling and tuning strategies.Drive DevOps practices: CI/CD pipelines with Jenkins, SonarQube, and Nexus; emphasis on automation, security, and deployment efficiency.Implement secure coding practices, vulnerability management, and compliance throughout the development lifecycle.Collaborate with cross-functional teams and stakeholders; analyze requirements, provide technical guidance, and drive solutions to completion.Mentor junior developers and promote a culture of continuous improvement.End-to-end ownership: analyze, design, implement, test, and deploy tasks with minimal supervision; take ownership of codebases when needed.Frontend development with React (TypeScript), webpack, ES6+, UI built with Ant Design; testing with Jest and React Testing Library.Work with MinIO or similar bucket-based storage; manage authentication/authorization (RBAC) and token-based security (JWT).Required qualificationsStrong experience with Java, Maven, and building large-scale applications using Quarkus or Spring.Deep expertise with MongoDB and PostgreSQL, including performance-oriented data access and indexing.Proven experience with Kafka for event-driven architectures and ELK stack for monitoring/troubleshooting.Solid knowledge of performance profiling and optimization for both code and database layers.Proficient in Docker, Kubernetes, Jenkins, SonarQube, and Nexus (DevOps / CI-CD focus).Security-minded: secure coding practices, vulnerability management, and compliance awareness.Excellent communication and collaboration skills; ability to work with product owners, architects, and engineers.Experience with Agile methodologies and delivering software in iterative cycles.Exposure to performance profiling tools and security tooling (e.g., Snyk, OWASP).Proactive, independent mindset with a track record of taking ownership of tasks end-to-end.Frontend: React with TypeScript, webpack, ES6+; UI with Ant Design; testing with Jest and React Testing Library.MinIO or similar bucket-based storage experience.Knowledge of RBAC and JSON Web Tokens (JWT) for authentication/authorization.Nice-to-haveBitbucket experience (Git) is a plus.Experience taking over a codebase with minimal handover.Familiarity with additional cloud environments (AWS/Azure/GCP) and related tooling.Location and startLocation: Brussels, Belgium (hybrid option available)Start date: NovemberIf you’re excited by building scalable, secure, end-to-end solutions and leading the charge from design to deployment, we’d love to hear from you.