Description
Sr .IAM Developer (.Net)
Client: Not for Profit
Role: Sr .IAM Developer (.Net)
Job Type: Contract (6 months)
Location: Remote EST hrs
Your New Company
Our client is a not-for-profit organization and seeking senior software developer with expertise in SSO, Oauth, .Net.
Your New Role:
Project is to unify member login system between main website, e-commerce site (third party), and e-learning site in development (third party) using a modern SSO implementation. With the client as the Identity Provider, the new system must connect to their on-the-prem-member database, issuing tokens and claims based on that data; it must be secure, performant, and extensible to future services.
• Design and implement a secure, standard-compliant Single Sign-On (SSO) system using OAuth 2.1 / OpenID
Connect (OIDC), with the organization serving as the Identity Provider.
• Deploy and configure the Identity Provider (IdP) to support the new authentication system.
• Define, implement, and document the token and claims model.
• Develop a comprehensive database migration plan and migrate existing Umbraco 4 / SQL Server user data into
the new SSO platform.
• Integrate the SSO solution with internal and external web applications.
• Produce detailed documentation for all secure integrations and system interactions.
• Prepare, test, and validate a fully production-ready configuration for deployment.
• Train the existing IT team on maintenance, monitoring, and ongoing support of the solution.
What You’ll Need:
• Experience working in a Microsoft Windows domain environment.
• Identity & Security:
o Strong understanding of OAuth 2.1 and OpenID Connect (OIDC) flows (Authorization Code Flow, PKCE, Refresh
Tokens, JIT migration etc.)
o Experience with IdentityServer4 or Duende IdentityServer (self-hosted).
1. Experience implementing IdPs and integrating RPs (clients)
2. Experience with OWIN/Katana
• Authentication Frameworks / Libraries:
o ASP.NET Core Identity,
o Duende IdentityServer
o Familiarity with JWT, JWK, and claims-based authorization
• Web & API Development:
o C# / ASP.NET Core (middleware, controllers, dependency inversion, dependency injection)
o RESTful API design and token-secured endpoints
o Understanding of classic ASP.NET Membership / Forms Authentication to support Umbraco 4 migration.
o Experience implementing logging and monitoring for authentication systems (e.g., audit logs, failed login alerts,
token usage logs).
3. Knowledge of Windows Server / IIS deployment
4. Familiarity with .NET Framework 4.6.1 and WebForms
• Database Integration & Migration:
o SQL Server / T-SQL proficiency
o Experience with data migrations (hash migrations, identity mapping, user normalization)
5. Knowledge of Umbraco 4 Membership Provider or older ASP.NET Membership schemas
6. Security Best Practices:
o Familiarity with PBKDF2 / bcrypt / Argon2 password hashing
o Secure handling of PII, tokens, and secrets
o Understanding of CORS, CSRF, TLS, and OWASP Top 10
Experience with any of following would be considered a strong asset:
• JavaScript experience for handling redirects and tokens in browser-based apps / experience with modern
frameworks such Blazor.
• Docker, CI/CD pipelines (GitHub Actions / Azure DevOps) for deployment and version control
• Experience testing authentication and authorization flows (unit and integration tests; Postman, Swagger etc)
• Understanding of affiliate-based identity design (users belonging to multiple orgs).
• Familiarity with Canadian privacy law (PIPEDA/FIPPA) for user data handling.
• Comfortable training internal developers on using and maintaining the new SSO endpoints and claims.
What You’ll get in Return
The client is offering a contract engagement with remote option.
