Dependency Injection Patterns When to Use This Skill Use this skill when: - Organizing service registrations in ASP.NET Core applications - Avoiding massive Program.cs/Startup.cs files with hundreds of registrations - Making service configuration reusable between production and tests - Designing libraries that integrate with Microsoft.Extensions.DependencyInjection Reference Files - advanced-patterns.md: Testing with DI extensions, Akka.NET actor scope management, conditional/factory/keyed registration patterns --- The Problem Without organization, Program.cs becomes unmanageable: Problems: h…