cover image
ATOS

Full Stack Engineer

Hybrid

Brussels region, Belgium

Freelance

18-01-2026

Share this job:

Skills

Java JavaScript TypeScript MongoDB PostgreSQL CI/CD DevOps Docker Kubernetes Monitoring Jenkins Agile methodologies git react Software Development Agile Spring Maven CI/CD Pipelines Kafka Microservices

Job Specifications

Full Stack Developer

B2B Contract for 1 year and possible extensions

Brussels Onsite 2 or 3 days/week

Key Responsibilities:

Software Development: Design and develop high-performance, scalable

applications using Java and Quarkus, ensuring that code is maintainable, efficient, and aligned with best practices.

Database Optimization: Architect and optimize MongoDB and PostgreSQL schemas, queries, and indexing strategies to achieve high performance and scalability.
Microservices s Messaging: Develop and scale microservices using Kafka for messaging, integrating with the ELK stack for logging, monitoring, and

troubleshooting.

Performance Engineering: Identify, analyze, and optimize system performance bottlenecks in both code and infrastructure. Ensure optimal performance through rigorous profiling, testing, and fine-tuning.
DevOps: Expertise with DevOps and CI/CD principles, Use pipelines with Jenkins,

SonarQube, and Nexus, focusing on security, automation, and deployment efficiency.

Security: Implement secure coding practices throughout the development lifecycle.
Mentorship: Provide guidance to junior developers, sharing knowledge and fostering a culture of continuous improvement.
Stakeholder Interaction: Work closely with product owners, architects, and other stakeholders to understand requirements, provide technical insights, and deliver effective solutions.
End-to-End Ownership: Take full ownership of tasks from analysis through design

to implementation and deployment. Be proactive in driving solutions independently, ensuring high-quality and timely delivery.

Storage: Experience with bucket based storage solutions, like MinIO.
Authentication s Authorization: Knowledge of authorization concepts like Role- Based Access Control (RBAC).Knowledge of authentication concepts like JSON WebTokens.
Frontend: proven experience with

Core technologies: React (with typescript), webpack (bundling and build configuration) and modern Javascript (ES6+)
UI C Styling: Ant design
Testing: Jest (unit/integration testing)and React Testing Library

Technical Skills s Qualifications:

Proven experience with Java, Maven and Quarkus/Spring in building large-scale applications.
Strong experience with Git, ideally Bitbucket
Strong background in MongoDB and PostgreSQL, with a focus on optimizing data access and ensuring scalability.
Expertise in Kafka for building event-driven systems and integrating with the ELK stack for monitoring and troubleshooting.
Deep understanding of performance optimization and profiling techniques for both

code and database layers.

Strong experience with Docker, Kubernetes, Jenkins, SonarQube, and Nexus for DevOps and CI/CD pipelines.
Ability to implement security best practices, including secure coding, vulnerability management, and compliance.
Solid experience in Agile methodologies with a focus on delivering high-quality software in iterative cycles.
Exposure to performance profiling tools and security tools (e.g., Snyk, OWASP).

Interpersonal Skills s proven maturity

Excellent soft skills, including the ability to analyze requirements, communicate effectively with cross-functional teams, and take initiative and drive tasks to completion.
A proactive and independent mindset, with the ability to work with minimal supervision and take full responsibility for end-to-end delivery
Not afraid to completely take over a codebase without proper handover by a previous team of developers.

About the Company

This account discusses mainly (but not exclusively) the activities of Tech Foundations - the Atos Group business line leading in managed services, focusing on hybrid cloud & infrastructure, employee experience and technology services, through decarbonized, automated and AI-enabled solutions. Eviden designs the scope composed of Atos’ digital, cloud, big data and security business lines. It will be a global leader in data-driven, trusted and sustainable digital transformation. Visit Eviden: https://www.linkedin.com/company/e... Know more