csharp

A prerendered Blazor component runs its initialization twice and loses state at the interactive handoff. Fix it with the [PersistentState] attribute or the PersistentComponentState service in .NET 11.

Two ways to call Claude from C#: the official Anthropic .NET SDK directly, or the provider-neutral Microsoft.Extensions.AI IChatClient that wraps it. When each wins, what you lose at the abstraction boundary, and why it is not actually either/or. With claude-opus-4-8 and claude-sonnet-4-6 examples.

Swashbuckle is gone from the ASP.NET Core templates. Here is how to generate and serve an OpenAPI document in .NET 11 with the built-in Microsoft.AspNetCore.OpenApi package: AddOpenApi, MapOpenApi, transformers, multiple documents, build-time generation, and a UI on top.

Stamp CreatedBy/ModifiedOn columns and write a full change-trail with an ISaveChangesInterceptor in EF Core 11, including the DI lifetime, current-user, and ExecuteUpdate gotchas.

At Build 2026 GitHub shipped Copilot SDK 1.0 GA with a first-class .NET package. You can now drive the same planning, tool-calling, and multi-turn agent runtime from C# code, BYOK included.

Organize Minimal APIs into resource extension methods with MapGroup. Understand nested routes, shared metadata, filters, authentication and testing.

ASP.NET Core 11 has built-in validation for minimal APIs: call AddValidation, annotate your request record with DataAnnotations, and a source generator validates the bound model and returns 400 ProblemDetails before your handler runs. No controllers, no FluentValidation, no manual checks.

For a new .NET agent in 2026, start on Microsoft Agent Framework 1.0. Semantic Kernel is in maintenance mode. Here is the side-by-side and the one case where SK still wins.

A practical checklist for reverting ValueTask and ValueTask<T> return types to Task and Task<T>, what breaks at the call sites, how to verify each change, and how to know whether the swap was ever worth it.

A step-by-step checklist to move a standalone Blazor Server app to the unified Blazor Web App template on .NET 11, keeping every page on InteractiveServer with zero behaviour change.