Fullstack .NET Developer

Fullstack .NET Developer (Freelance) – 4 months – Brussels Belgium

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About the Role

RELYzIT Talent is seeking an experienced Fullstack .NET Developer for a high-impact, freelance assignment with our client in Brussels. This is a unique opportunity to join a dynamic, bilingual IT environment and play a pivotal role in building and maintaining mission-critical applications. You’ll collaborate with multidisciplinary teams, leveraging your expertise to deliver robust, scalable solutions that directly shape the future of digital services.

Why This Role Matters

Our client’s IT department is the engine behind essential digital transformation, serving a diverse, bilingual user base. As a Fullstack .NET Developer, you will be instrumental in designing, developing, and optimizing applications that empower both internal teams and end-users. Your work will drive operational excellence, ensure high-quality deliverables, and support the organization’s agile evolution. The stakes are high: your code will impact thousands, and your technical leadership will set new standards for quality and innovation.

What You’ll Be Doing

• Designing, developing, and maintaining .NET applications using C# and .NET Core, ensuring high performance and reliability.


• Translating functional analyses into robust technical solutions, collaborating closely with business analysts to validate technical specifications.


• Analyzing and resolving complex technical issues, including level two bug fixes, and providing technical support to peers.


• Driving continuous improvement by implementing automation, CI/CD pipelines, and unit testing to guarantee stable development, test, and production environments.


• Collaborating within agile, multidisciplinary teams (Scrum/SAFe), working iteratively with developers, testers, business analysts, product owners, and scrum masters.


• Contributing to and reviewing technical documentation, sharing knowledge, and mentoring junior developers to elevate team capability.


• Staying ahead of technology trends and best practices, proactively integrating new methodologies to enhance software quality and team performance.

What We’re Looking For

• Proven ownership mindset: you take initiative, drive outcomes, and thrive in environments where your impact is visible.


• Exceptional problem-solving and analytical skills, with a passion for tackling complex challenges head-on.


• Continuous learner: you actively seek out new technologies and methodologies, always striving for improvement.


• Strong communicator: able to explain technical concepts clearly to both technical and non-technical stakeholders.


• Collaboration-oriented, socially skilled, and adaptable—comfortable switching between tasks and priorities in a fast-paced setting.


• Proactive, autonomous, and customer-focused, with a strong sense of responsibility and commitment to delivering value.

Technical Skills

• 5+ years of experience as a .NET Developer (Fullstack: frontend and backend)


• Confirmed expertise in .NET Framework, .NET Core, and C#


• Blazor (Confirmed)


• MS SQL (Confirmed)


• NServiceBus or other messaging patterns (Confirmed)


• Azure DevOps (Confirmed)


• Azure Cloud experience with CI/CD pipelines (Junior)


• gRPC (Junior)


• Windows Communication Foundation (WCF) (Junior)


• Knowledge of Oracle PL/SQL is a plus

Language Proficiency

• Fluency in either French or Dutch (spoken and written)


• Basic understanding and communication skills in the second language (French or Dutch)


• English: understanding required

Other Requirements

• Bachelor’s or Master’s degree in Computer Science or equivalent experience


• Minimum 3 years of experience working in Agile/Scrum environments


• Experience working in multidisciplinary, bilingual teams is highly valued


• Partial remote work: 2 days per week onsite, 3 days remote


• Freelance contract: 4 months, with immediate impact on high-visibility projects