Daily notes on .NET, C#, EF Core, MAUI, Blazor, and Flutter - for developers who ship.

Blazor has no syntax for a variable tag name, and DynamicComponent only renders component types. Override BuildRenderTree and call builder.OpenElement(0, $"h{level}"). Covers attribute splatting, why the tag name must be clamped before it reaches the DOM, why changing the level rips the element out of the DOM even with @key, and an auto-levelling variant built on a cascading value.

Inside testWidgets the ambient clock from package:clock is already fake, but it starts at whatever wall time the test began. Pin it for a whole suite by overriding runTest on a custom AutomatedTestWidgetsFlutterBinding installed from flutter_test_config.dart. Verified on Flutter 3.44.2, clock 1.1.2, fake_async 1.3.3.

MAUI 10.0.100 ships MauiBlazorWebViewBuilderExtensions.UsePlatformHandler, a supported seam for replacing BlazorWebViewHandler without reimplementing everything AddMauiBlazorWebView() registers. Two overloads, one ordering trap.

A headersHelper field on url marketplaces and catalog entries runs a local command that prints HTTP headers, so an internal plugin catalog behind S3 or an artifact repo can authenticate with a short-lived token. Here is the schema, the consent prompt, and the header names Claude Code drops.

MCP error -32022 means your client opened at 2025-11-25 but the server only serves 2026-07-28. Make one side dual-era instead of pinning a version.

There is no HasBeenEnumerated flag on IEnumerable<T>. Here is what TryGetNonEnumeratedCount actually checks, why Enumerable.Range passes an ICollection<T> test, and the guard that avoids a wasted ToList().

Declare a generic extension block with a struct, Enum constraint and you get Status.Values, Status.Count, and Status.Parse on every enum in your solution. The receiver shape, the CS0704 and CS0428 traps, and why you must cache Enum.GetValues.

A bool helper method throws "could not be translated". An Expression<Func<T, bool>> does not. Here is how to compose, nest, and reuse expression trees in EF Core 11 without LINQKit, with the real SQL for every case.

The JEP 472 warning on JDK 24+ is harmless and prints once. Fix it by matching your JDK to a Gradle version that supports it, not by pasting flags into gradle.properties.

getToken() runs before APNs hands iOS the device token. Poll getAPNSToken() until it returns non-null, then call getToken(). Check the Push Notifications capability if it never arrives.