Senior .NET & Blazor UI Lead - Frontend Architect

Keystone Solutions; Brussel Hoofdstad; Hybrid; EUR 70,000 - 90,000; Full time

Job summary

Keystone Solutions is seeking a Senior .NET Developer (Blazor, UI focus) on a consultant mission at a client site. You will lead UI architecture while delivering hands-on features using C#, Blazor, and modern .NET.

You will collaborate with analysts and UX, ensure accessibility, and integrate with REST APIs and secure authentication. Expect a dynamic, technically focused environment with knowledge sharing and architectural oversight.

Qualifications

• Agile/Scrum experience with practical application.
• Experience with Blazor and Razor components.
• Strong C# and .NET development skills.
• Experience with EF Core and SQL.
• Knowledge of REST APIs and JSON exchanges.
• Experience with secure auth (OAuth2 / OpenID Connect).
• Tests: unit, component, and UI automation.
• WCAG 2.1 AA accessibility knowledge.

Responsibilities

• Provide technical UI leadership and enforce UI standards.
• Hands-on development with C#, Blazor, Razor components.
• Design scalable, maintainable front-end structures.
• Build responsive, accessible user interfaces across devices.
• Collaborate with analysts/UX to translate requirements.
• Integrate Blazor apps with REST APIs and secure auth flows.
• Maintain code quality via reviews and testing practices.
• Use Git and Azure DevOps for CI/CD pipelines.
• Coach other developers and share knowledge.
• Lead debugging across dev and prod environments.
• Evaluate technologies aligned with architecture and security decisions.

Skills

Agile / Scrum

AI-assisted development

Blazor and Razor components

C#

Entity Framework Core and SQL

HTML/CSS and responsive design

Modern .NET / ASP.NET Core

OAuth 2.0 / OpenID Connect / JWT

REST APIs and JSON exchanges

Testing (unit, UI, integration)

Web accessibility WCAG 2.1 AA

Tools

Git

Azure DevOps

CI/CD pipelines

Job description

Keystone Solutions is seeking a Senior .NET Developer (Blazor, UI focus) on a consultant mission at a client site. You will lead UI architecture while delivering hands-on features using C#, Blazor, and modern .NET.

You will collaborate with analysts and UX, ensure accessibility, and integrate with REST APIs and secure authentication. Expect a dynamic, technically focused environment with knowledge sharing and architectural oversight.