NET Developer / Lead Backend Developer

Senior .NET Developer / Lead Backend Developer

Location: Toronto, Ontario
Work Model: Hybrid - 4 days onsite and 1 day remote
Experience Required: 12 15 years
Position Type: Contract

Job Summary

We are seeking an experienced Senior .NET Developer / Lead Backend Developer to design and develop scalable, secure and high-performance enterprise applications. The successful candidate will lead backend development initiatives, provide technical guidance and contribute to application architecture and design decisions.

This position requires strong expertise in C#, .NET 10, ASP.NET Core Web API, SQL Server, microservices and Azure services, along with hands-on experience integrating AI or Generative AI capabilities into enterprise applications.

Responsibilities

• Design, develop and maintain scalable, secure and high-performance RESTful APIs using C#, .NET 10 and ASP.NET Core.
• Lead backend development initiatives and provide technical guidance to engineering teams.
• Define and promote application architecture, design patterns, coding standards and development best practices.
• Design and implement scalable microservices, API gateways and distributed applications.
• Optimize APIs and backend services for performance, scalability, security, reliability and maintainability.
• Design, develop and optimize SQL Server databases.
• Create and optimize complex SQL queries, stored procedures, indexes and database structures.
• Implement authentication and authorization solutions using OAuth 2.0, JWT, RBAC and Azure AD/Entra ID.
• Collaborate with frontend development teams, including Angular developers, to design and integrate RESTful APIs.
• Design and implement secure solutions using Azure Key Vault and other Azure security services.
• Integrate AI and Generative AI capabilities into enterprise applications.
• Troubleshoot complex production issues using Application Insights, Azure Monitor, logging, tracing and debugging tools.
• Collaborate with product managers, architects, QA, DevOps and other engineering teams.
• Participate in Agile/Scrum activities, including sprint planning, daily stand-ups, retrospectives and technical-design discussions.
• Conduct code reviews and mentor developers on engineering standards and best practices.

Required Qualifications

• 12 15 years of professional software-development experience, with significant experience in backend development.

• Strong hands-on expertise in C#, .NET Core, .NET 10 and ASP.NET Core Web API.

• Advanced experience with SQL Server - mandatory, including:

  • Database design
  • Complex SQL queries
  • Stored procedures
  • Indexing
  • Query optimization
  • Performance tuning

• Strong experience designing and developing RESTful APIs and microservices.

• Experience with distributed systems and microservices architecture.

• Strong knowledge of authentication, authorization and identity-management concepts.

• Hands-on experience with OAuth 2.0, JWT, RBAC and Azure AD/Entra ID.

• Experience with Azure Key Vault and cloud-security best practices.

• Experience with API gateways, Docker and Kubernetes.

• Experience monitoring and troubleshooting applications using Azure Monitor and Application Insights.

• Hands-on experience integrating Azure OpenAI, OpenAI APIs or other LLM-based services into enterprise applications.

• Strong understanding of software architecture, design patterns and clean coding principles.

• Excellent problem-solving, communication and technical-leadership skills.

• Ability to collaborate effectively with cross-functional and geographically distributed teams.

• Must be comfortable working from the Toronto office four days per week.

Preferred Qualifications

• Experience integrating backend APIs with Angular applications.
• Experience deploying containerized applications in Azure or other cloud environments.
• Strong experience with Docker and Kubernetes in production environments.
• Experience leading development teams and mentoring engineers.
• Experience building enterprise applications incorporating Generative AI capabilities.