csharp

A staged playbook for removing sync-over-async from an existing .NET codebase: inventory with analyzers, measure ThreadPool starvation, convert one call chain at a time, and ratchet the count to zero on .NET 11.

A step-by-step guide to converting $-interpolated ILogger calls into message templates and [LoggerMessage] source-generated methods on .NET 11: what breaks, how to sweep a codebase with CA2254, how to verify the JSON state, and how to roll back.

A decision guide for ASP.NET Core 11: middleware runs for every request before your handler binds, endpoint filters run only for the matched endpoint after binding and can see the typed arguments. Includes a feature matrix, when-to-pick-each scenarios, the ordering rules, and the gotchas that force the choice.

await is the right answer almost every time. When you truly must block, GetAwaiter().GetResult() beats .Result and .Wait() because it throws the original exception. A decision matrix for .NET 11 and C# 14.

Cancelling the CancellationToken you pass to InvokeAsync now reaches the server and cancels the hub method. This closes a SignalR request open since 2019.

In ASP.NET Core 11, return Results<T1, TN> with TypedResults for minimal APIs and ActionResult<T> for controllers. Treat bare IResult and bare IActionResult as escape hatches: they compile for any response but describe nothing to OpenAPI, so you pay for them in hand-written ProducesResponseType attributes.

Use CreateBuilder for a normal app, CreateSlimBuilder when you publish trimmed or Native AOT behind a TLS proxy, and CreateEmptyBuilder only when you want to register every service yourself. Here is the feature matrix and the gotchas that force the call.

Output caching is the right default for almost every server-side app in ASP.NET Core 11. Response caching only wins when your goal is to steer browser and proxy caches through HTTP headers. Here is the decision, with a feature matrix and the gotchas that force the call.

Sequential for pipelines, concurrent for fan-out, group chat for moderated rounds, handoff for routing, magentic for open-ended planning. The C# builders and how to choose.

CS4014 means you called a Task-returning method without awaiting it. Add await, or discard with _ = if fire-and-forget is truly intended, and handle exceptions.