.NET Worker Services

Trigger On

• building long-running background services or scheduled workers
• adding hosted services to an app or extracting them into a worker process
• reviewing graceful shutdown, cancellation, queue processing, or health behavior

Documentation

• Worker Services in .NET
• Background tasks with hosted services in ASP.NET Core
• Create Windows Service using BackgroundService
• App health checks in .NET
• Health checks in ASP.NET Core

References

• patterns.md - BackgroundService patterns, graceful shutdown, and health check implementations
• anti-patterns.md - Common worker service mistakes and how to avoid them

Workflow

1. Use BackgroundService as your base class:

   • Provides standard StartAsync/StopAsync handling
   • Focus on implementing ExecuteAsync only
   • Proper cancellation token management built-in

2. Handle scoped dependencies correctly:

   • Create service scopes for scoped services
   • No scope is created by default in hosted services

3. Implement graceful shutdown:

   • Propagate cancellation tokens throughout
   • Complete work promptly when token fires
   • Avoid ungraceful shutdown at timeout

4. Keep execution loop thin:

   • Move business logic to testable services
   • Handle exceptions to prevent service crashes
   • Use PeriodicTimer for scheduled work