Senior Developer .NET (AI-First)

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Senior Developer .NET (AI-First) (Freelance) - 4 months - Brussels Belgium

Intro

RELYzIT Talent is seeking a Senior Developer .NET (AI-First) for a high-impact, freelance assignment with our client, a leading federal institution at the heart of Belgium’s digital transformation. This is your opportunity to shape digital products that directly influence the social security and healthcare landscape for millions. Join a multidisciplinary team where your expertise will drive real-world outcomes and set new standards for public sector innovation.

Why This Role Matters

Our client is embarking on a pivotal digital transformation journey, modernizing complex IT systems that underpin essential public services. As a Senior Developer .NET (AI-First), you will be instrumental in delivering robust, future-ready software solutions that enhance efficiency, reliability, and accessibility for citizens nationwide. Your work will not only solve technical challenges but also empower a healthier, more secure society.

What You’ll Be Doing

• Designing, developing, and maintaining high-quality .NET applications in a fast-paced, agile environment.


• Driving code quality through rigorous code reviews, automated testing, and adherence to best practices.


• Collaborating closely with product managers, solution architects, and fellow developers to deliver impactful digital products.


• Contributing to technical solution design and architectural decisions, translating ideas into concrete implementations.


• Identifying, troubleshooting, and resolving bugs and performance bottlenecks in existing applications.


• Integrating AI tools and methodologies into the daily development workflow, championing AI-assisted development.


• Documenting developed components to ensure maintainability and knowledge sharing within the team.


• Actively participating in agile ceremonies, including sprint planning, refinements, and retrospectives.


• Fostering a culture of continuous improvement and open knowledge exchange, including AI knowledge transfer to peers.

What We’re Looking For

• Proven expertise in .NET C# development, with a strong track record of delivering production-grade solutions.


• Deep understanding of REST API development and SQL relational databases.


• Hands-on experience with CI/CD pipelines and cloud platforms, particularly Azure.


• Advanced knowledge of Agile/Scrum methodologies, thriving in iterative, collaborative environments.


• Demonstrated ability to integrate and leverage AI tools in software development workflows.


• Experience with test automation (unit and integration testing) and Git version control.


• Ability to communicate and collaborate effectively in multidisciplinary teams.


• Ownership mindset: proactive, solution-oriented, and committed to delivering measurable impact.


• Experience in the public sector is a plus, but not required.

Technical Skills

• .NET C# development (Confirmed)


• REST API development (Expert)


• SQL Data / Relational Databases (Confirmed)


• CI/CD pipelines (Confirmed)


• Cloud (Azure) (Confirmed)


• Test automation (unit, integration) (Confirmed)


• Git version control (Confirmed)


• AI-assisted development (Confirmed)


• AI knowledge transfer to development teams (Confirmed)


• Agile / Scrum (Expert)


• Public Sector Experience (Junior, a plus)

Language Proficiency

• Professional proficiency in English is required.


• Ability to communicate effectively with both Dutch-speaking and French-speaking stakeholders is highly valued.

Other Requirements

• Partial remote work is possible; on-site presence in Brussels may be required for key meetings and collaboration.


• This is a freelance position with a fixed duration of 4 months.


• Immediate availability is a strong advantage.