Senior .NET/Application Modernization Consultant (legacy applications migration)

Senior .NET/Modernization Consultant (Identity Federation)

Duration: 2-3 months (Short-term engagement).

Location: Remote(work hour flexible)- Can consider after work hours also.

Project Overview:
The client is initiating a high-priority migration project to modernize the authentication layer of 19 legacy applications. The goal is to transition from on-premise Active Directory (AD) authentication to Microsoft Entra ID (formerly Azure AD) Federated authentication.
Scope of Work:

• Direct Migration: Lead the hands-on conversion of an initial 3 4 applications (mixture of .NET 4.7.2 and Classic ASP).
• Knowledge Transfer: Act as a technical mentor to the existing development team, providing "over-the-shoulder" training and documentation to enable them to migrate the remaining 15+ applications independently.
• Duration: 2 3 months (Short-term engagement).

Technical Requirements

• Legacy Framework Expertise: Deep proficiency in .NET Framework 4.7.2 and Classic ASP.
• Identity & Access Management (IAM): Proven experience migrating applications from Windows Authentication/LDAP to Entra ID (Azure AD).
• Protocols: Strong understanding of modern identity protocols, specifically SAML 2.0 and OpenID Connect (OIDC) / OAuth 2.0.
• Middleware: Experience using OWIN middleware or MSAL libraries to handle federation in older .NET environments.
• Legacy Integration: Ability to implement modern authentication patterns within Classic ASP environments (e.g., using headers, reverse proxies, or custom COM wrappers).

Core Responsibilities

• Assess current AD-integrated codebases to identify dependencies.
• Configure App Registrations and Enterprise Applications within the Microsoft Entra admin center.
• Refactor authentication logic to support Federated SSO.
• Conduct code reviews and training sessions for the permanent developer staff.

Soft Skills

• Consultative Approach: Ability to explain complex identity concepts to developers unfamiliar with federation.
• Efficiency: Capable of delivering a "gold template" migration within a tight 60-90 day window.