When this page is relevant
Use compile-time diagnostics to catch singleton-to-scoped and singleton-to-transient lifetime mismatches before stale state or thread-safety bugs ship.
Problem guide
Find Captive Dependencies In ASP.NET Core
This page is for teams searching for captive dependency detection in ASP.NET Core, worker services, and generic-host apps.
Recommended install command
dotnet add package DependencyInjection.Lifetime.Analyzers --version 2.2.2Relevant diagnostics
The rules that cover this failure mode
DI003
Captive Dependency
singleton services capturing scoped or transient dependencies, including constructor injection and high-confidence factory paths such as inline delegates, method-group factories, keyed resolutions, and `ActivatorUtilities.CreateInstance(...)` without explicit constructor arguments.
DI009
Open Generic Captive Dependency
open generic singleton registrations that depend on shorter-lived services.