Use the Microsoft.Extensions stack correctly across Generic Host, dependency injection, configuration, logging, options, HttpClientFactory, and other shared infrastructure patterns. USE FOR: wiring dependency injection, configuration, logging, or options; introducing Generic Host patterns into non-web .NET apps; cleaning up service registration, typed HTTP. DO NOT USE FOR: unrelated stacks; generic tasks that do not need this specific guidance. INVOKES: inspect the repository context, edit targeted files, and run relevant build, test, lint, or validation commands when changes are made.
Use the Microsoft.Extensions stack correctly across Generic Host, dependency injection, configuration, logging, options, HttpClientFactory, and other shared infrastructure patterns. USE FOR: wiring dependency injection, configuration, logging, or options; introducing Generic Host patterns into non-web .NET apps; cleaning up service registration, typed HTTP. DO NOT USE FOR: unrelated stacks; generic tasks that do not need this specific guidance. INVOKES: inspect the repository context, edit targeted files, and run relevant build, test, lint, or validation commands when changes are made.
compatibility
Relevant to console apps, workers, ASP.NET Core apps, functions, and reusable libraries.
Microsoft.Extensions for .NET
Trigger On
wiring dependency injection, configuration, logging, or options
introducing Generic Host patterns into non-web .NET apps
cleaning up service registration, typed HTTP clients, or shared infrastructure code
Workflow
Prefer the Generic Host for apps that need configuration, DI, logging, hosted services, or coordinated startup.
Keep service registration predictable: composition at the edge, concrete implementations hidden behind interfaces only where that abstraction buys flexibility.
Use options binding for structured configuration and validate configuration at startup when bad settings would fail later at runtime.
Prefer IHttpClientFactory and typed or named clients for outbound HTTP instead of ad-hoc singleton or per-call HttpClient usage.
Use logging categories and config-driven log levels rather than scattered ad-hoc logging behavior.
Avoid building mini-frameworks over Microsoft.Extensions unless the repo genuinely needs reusable composition primitives.
Deliver
clean host wiring and service registration
configuration and logging that are observable and testable
infrastructure code that fits naturally with the .NET stack
Validate
service lifetimes are correct
configuration is strongly typed where it matters
host setup remains easy to debug and reason about
References
patterns.md - DI patterns, Configuration patterns, Options pattern, Logging patterns, HttpClientFactory patterns, Hosted Service patterns
anti-patterns.md - Common mistakes with DI, configuration, options, logging, HttpClient, and hosted services
