.NET Developer

ICTZZP toegestaan# .
NET Developer (Blazor, UI focus)Smals Bouwgrondstoffen B.
V. Brussel 1 maandGepubliceerd 5 uur geleden
· Opportunity ID: Tarief indicatie €65–€81.25 /uUren 40 u/wStart 22 Nov 2026Duur 1 maandInteresse in deze opdracht?## De opdrachtNIHDI context of workBuild the future of public health technology at NIHDI as a Senior .
NET Developer with a user-interface focus. Your work will directly support digital services that contribute to the health and wellbeing of millions of people in Belgium. You will design and deliver secure, accessible, responsive and high-impact business applications end to end, from the Blazor user interface to the .
NET services behind it, while guiding colleagues and contributing to sound technical decisions.
You will join an ICT department of approximately 250 professionals, actively engaged in more than 50 projects across different phases of development. NIHDI is transforming its application landscape toward a modern, cloud-native architecture on Microsoft Azure, using Azure Service Bus and containerised workloads to improve the way systems are built, integrated and scaled. A Platform Engineering team provides the shared libraries, the design system, the DevOps pipelines and the standards that every application team builds on.
NIHDI standardised its web user interfaces on Blazor so that one .
NET skill set covers the whole application. The user interface is therefore not a separate discipline: it is the part of the .
NET application that faces citizens, healthcare professionals and NIHDI employees, and it has to be accessible, consistent and fast. This transformation also includes the responsible integration of AI into business applications and into the way we develop them.
Join NIHDI to build smart, secure and purpose-driven digital services, and help shape the future of public health technology.
Job purposeThe Senior .
NET Developer (Blazor, UI focus) is responsible for the design, development, integration and maintenance of modern business applications within NIHDI's application landscape, with particular ownership of their user interfaces. The role combines advanced hands-on development with technical leadership, coaching and close collaboration with analysts, architects, UX stakeholders, security specialists, the Platform Engineering team and operational teams.
The developer translates functional and technical requirements into robust, reusable and accessible solutions. The role ensures that applications provide a consistent and accessible user experience across devices and browsers, integrate correctly with NIHDI services and APIs, reuse the shared component library and design system, and comply with organisational standards for architecture, security, quality, maintainability and delivery.
As a senior member of the development team, the developer helps resolve complex technical challenges, makes well-founded design choices, improves engineering practices and supports other developers through coaching and code reviews. The role remains strongly hands-on and contributes directly to feature development, testing, troubleshooting and continuous improvement, on the user interface as well as on the services it depends on.

Key responsibilities
Technical leadership for the user interface: Provide technical direction for Blazor development across teams and promote a consistent approach to UI architecture, reusable components, coding standards and engineering practices, in line with the Platform Engineering team's standards.
Hands-on development: Dedicate a significant part of the role to developing features, reusable components, prototypes, technical improvements and bug fixes using C#, modern .
NET, Blazor and Razor components, and the .
NET Web APIs they rely on.
UI architecture and component design: Design scalable, maintainable and reusable front-end structures that align with NIHDI architectural principles, and contribute to the shared component library built on MudBlazor and the NIHDI design system.
Accessibility and responsive design: Build responsive user interfaces with semantic HTML and modern CSS that meet WCAG 2.1 level AA, as required of Belgian public bodies under the European Web Accessibility Directive, and take account of usability, browser compatibility and NIHDI's public-service context.
Requirements analysis: Collaborate with functional and business analysts and UX stakeholders to clarify requirements, assess feasibility and translate user and business needs into robust technical solutions.
API integration: Integrate Blazor applications with REST APIs and JSON-based services, including typed clients, appropriate error handling, state management, validation and resilience; extend the Web APIs when a feature requires it.
Authentication and application security: Implement secure authentication and authorisation flows using OAuth 2.0 and OpenID Connect for the three audiences NIHDI serves (internal users, healthcare professionals and citizens, each with its own identity provid