Senior .NET Backend Developer 6 Months Contract

We are looking for a Senior .NET Backend Developer to develop, maintain, and support a secure certificate provisioning solution that enables secure device onboarding and end-to-end certificate lifecycle management.

The role combines hands-on backend development with .NET 8/10, ASP.NET Core, Azure services, X.509 certificates, Windows Services, DevOps, and production support. You will work across application development, cloud services, security, integrations, deployment, and operational support.

The ideal candidate will have strong backend development experience and be comfortable working in production environments where security, reliability, troubleshooting, and automation are critical.

Following an initial on-site introduction, the role can be performed remotely.

• Design, develop, maintain, and support .NET 8/10 backend services, Windows Services, and ASP.NET Core APIs.
• Implement and support X.509 and other certificate-related workflows, including certificate generation, validation, storage, renewal, and lifecycle management.
• Develop and maintain integrations with Azure Blob Storage, Azure Key Vault, and Application Insights.
• Troubleshoot and resolve production issues across application, infrastructure, integration, and certificate-related workflows.
• Maintain and improve CI/CD pipelines, deployment automation, and release processes using Azure DevOps.
• Support production deployments and participate in production rollouts.
• Contribute to automated and manual testing, code reviews, and software engineering best practices.
• Participate in requirements clarification, technical discussions, and coordination with relevant stakeholders.
• Contribute to the continuous improvement of system security, reliability, performance, and maintainability.
• Provide technical support and investigation for issues across development, test, and production environments.

Essential Skills & Experience

• Strong professional experience with C# and .NET 8/10.
• Solid experience developing ASP.NET Core APIs and backend services.
• Experience developing and maintaining Windows Services.
• Hands-on experience with Microsoft Azure, particularly:
• Azure Blob Storage
• Azure Key Vault
• Azure Application Insights
• Practical knowledge of X.509 certificates and certificate lifecycle management.
• Strong understanding of asynchronous programming, dependency injection, file handling, and backend troubleshooting.
• Experience with Git, PowerShell, CI/CD pipelines, and Azure DevOps.
• Experience working with Windows Server environments.
• Strong troubleshooting and problem-solving skills, with the ability to investigate issues across application and infrastructure layers.
• Comfortable working with production systems and supporting releases and deployments.

Desirable Skills & Experience

• 5+ years of professional .NET backend development experience.
• Familiarity with OpenSSL and certificate automation.
• Experience with secure credential and secret management.
• Experience with production monitoring, observability, and application diagnostics.
• Experience developing or maintaining enterprise integrations.
• Experience working in security-focused or device onboarding environments.
• Understanding of secure software development practices and enterprise deployment processes.

Working Environment

This is a hands-on engineering role covering both development and production support. The successful candidate should be comfortable taking ownership of technical issues from investigation through to implementation, deployment, and production rollout.

Location: Initial on-site introduction, followed by remote working.

Role focus: .NET Backend Development | Azure | Certificate Management | DevOps | Production Support | Security