Senior .NET Backend Engineer (Cloud-Native API & Azure Platform) / Senior .NET Advance level Backend serverless expertise
Backend Services Engineering
Location: Toronto, ON (Hybrid)
We are seeking a highly skilled .NET backend engineer to design and build scalable, performant, and secure backend services supporting a healthcare company. You will work exclusively on backend systems and APIs — a separate React team handles the UI. This role requires deep expertise in .NET internals, cloud-native application design, and Azure-hosted microservice architectures.
Core Responsibilities:
• Architect, develop, and optimize backend services using modern .NET (8/9) with a focus on high throughput, low-latency execution, and scalable service design.
• Build secure and robust REST APIs, including authentication and authorization via OAuth 2.0 and JWT, with full API lifecycle and version management.
• Implement strong testing discipline, including unit tests, mocking strategies, and testable architectural patterns.
• Maintain code clarity and quality using clean C# language features, immutable data models, dependency injection, and reusable library/package design.
• Apply deep observability practices — structured logging, distributed tracing, metrics instrumentation, and API performance telemetry.
• Work within containerized environments for both development and production, using Docker, Dev Containers, and VS Code-based workflows.
• Deploy and run services on Azure PaaS environments, leveraging services such as AKS, Azure Container Apps, or Azure Functions.
• Apply strong security engineering discipline — encryption, input validation, hashing, secrets management and secure coding best practices.
• Collaborate with other engineering teams and contribute to engineering standards and architectural direction for backend and API services.
Required Technical Expertise:
• .NET & C# Engineering
• Production-grade backend experience using .NET 8/9
• Expert-level C# proficiency (modern language features)
• Strong knowledge of async/await, concurrency & event-driven design
• Advanced memory optimization skills: Span, Memory, ref struct, heap vs stack allocation understanding
• Proven experience with dependency injection patterns and testable architecture
• Experience building reusable NuGet packages & semantic versioning
• Deep understanding of .NET middleware, application hosting models, configuration models, and the full runtime lifecycle
• API & Platform Engineering
• Secure REST API design with OAuth2 / JWT token handling
• API versioning strategies (URL-based, header-based, compatibility management)
• API documentation and schema generation using OpenAPI/Swagger
• API metrics, monitoring, and diagnostics
• Containerization & Dev Tooling
• Hands-on Docker experience for development & production
• Custom Dev Container setups & debugging (VS Code)
• Proven ability to craft reliable, optimized Dockerfiles and multi-stage builds
• Azure-Hosted Service Development
Experience with Azure microservice platforms:
• Azure Kubernetes Service (AKS)
• Azure Container Apps (ACA)
• Azure Functions (container-based)
Operational knowledge of:
• Azure Monitor
• Application Insights
• Log Analytics
• Engineering for resiliency, performance, and error isolation
• Coding Style & Best Practices
• File-scoped namespaces
• Global using directives
Top-level programs
• Immutability and pattern matching
• Secure coding & exception handling practices
What Success Looks Like
• You write backend code that is fast, safe, predictable, and observable.
• You design APIs that are future-proof, versionable, and secure-by-default.
• You understand not just what .NET does — but why it does it.
• You treat containers, PaaS, and Azure as first-class engineering environments.
• You raise the technical bar for backend engineering across the team.
