.Net Developer

About the Role

We are looking for a freelance Senior .NET Developer to join a large-scale digital transformation project within the Belgian energy sector.

You will join an established Agile team working on secure authentication, authorization and digital identity solutions used across both modern and legacy applications. This is a hands-on development position combining .NET/C#, Java, cloud, security and DevOps.

The position is full-time and hybrid, with approximately 2 days per week onsite in the Brussels region.

Your Responsibilities

• Develop, test and document software components and services using C#/.NET and Java.
• Build and integrate authentication and authorization solutions.
• Develop and document REST-based integrations and sample applications.
• Configure and extend components such as API gateways, reverse proxies, directory services and authorization engines.
• Work with OAuth2, OpenID Connect (OIDC), SSO and MFA.
• Contribute to front-end development using Vue.js and Blazor.
• Work with LDAP and SQL Server.
• Deploy and maintain applications in Kubernetes / AKS environments.
• Improve CI/CD pipelines, automation and configuration management.
• Troubleshoot technical and integration issues.
• Participate actively in Agile/Scrum ceremonies.
• Document technical solutions, processes and architectures.
• Collaborate with developers, infrastructure teams and other technical stakeholders.

Must-Have Skills

• Strong professional experience with C# and .NET
• Professional Java development experience
• REST APIs, JSON and YAML
• JavaScript
• Vue.js and/or Blazor
• SQL Server and LDAP
• OAuth2 and OIDC
• Authentication & authorization concepts
• SSO, MFA, HTTPS, CORS and web security
• Kubernetes and/or AKS
• Git, CI/CD and DevOps practices
• Understanding of cryptographic concepts
• Good English, combined with Dutch and/or French

Nice to Have

• TypeScript, PowerShell or Bash
• React
• SAML2
• PKI, keystores and hash functions
• Experience with Keycloak, ADFS, Okta, Ping Identity or Entra ID
• Microservices architecture

Job Type: Full-time

Work Location: Hybrid remote in Brussels