Senior Software Enginer (C# / .NET)

Working at Tech Holding isn't just a job, it's an opportunity to be a part of something bigger. We are a full-service consulting firm that was founded on the premise of delivering predictable outcomes and high-quality solutions to our clients. Our founders and team members have industry experience and have held senior positions in a wide variety of companies – from emerging startups to large Fortune 50 firms – and we have taken our combined experiences and developed a unique approach that is supported by the principles of deep expertise, integrity, transparency, and dependability. About the Role We are looking for a skilled Senior C# / .NET Engineer to support a critical platform security and modernization initiative. This role focuses on backend/API enhancements, security implementation, and system reliability improvements in alignment with Azure- based infrastructure and data protection standards. Key Responsibilities  Design and develop secure backend services and APIs using C# / .NET.  Implement authentication and authorization mechanisms (SSO, RBAC, OAuth, JWT).  Integrate applications with Azure Active Directory (Entra ID).  Remove hardcoded secrets and integrate with Azure Key Vault.  Implement audit logging and monitoring hooks across services.  Build and enforce secure API communication standards.  Implement PII masking and secure data handling logic in applications.  Secure and optimize third-party integrations (Stripe, SendGrid, Twilio, etc.).  Support environment separation and deployment improvements.  Collaborate with DevOps and DB teams on security, DR, and compliance initiatives.  Participate in debugging, incident resolution, and root cause analysis.

Requirements:  5+ years of experience in C# / .NET development.  Strong experience with ASP.NET Core, Web APIs, and microservices architecture.  Experience implementing authentication & authorization (OAuth, JWT, SSO).  Hands-on experience with Azure services, especially Azure AD (Entra ID).  Experience with secure coding practices and data protection.  Familiarity with API integrations (Stripe, SendGrid, etc.).  Experience with logging frameworks and monitoring tools.  Understanding of CI/CD pipelines and cloud deployments.  Strong debugging, problem-solving, and communication skills.

Good to Have  Experience with containerization (Docker, Kubernetes)