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

A signed assembly must name its friend by the full 320-character public key, not the token, or the build fails with CS1726 or CS0281. Get the key with sn -p and sn -tp, or with a cross-platform .NET script, then put it in the Key metadata of an InternalsVisibleTo item in the .csproj. Covers the PublicKey property fallback, Moq's DynamicProxyGenAssembly2 key, and the line-break trap.

Use SystemEvents.SessionSwitch in a desktop or console app, override OnSessionChange in a Windows service, or hook WM_WTSSESSION_CHANGE yourself. Covers .NET 10 code for all three, the hidden '.NET System Events' thread, why services see logon but desktop apps do not, out-of-order notifications, and how to query the current lock state with WTSQuerySessionInformation.

A SET statement run once is wiped by DISCARD ALL the moment Npgsql returns the connection to its pool. Put search_path and statement_timeout in the startup packet with the Search Path and Options connection string keywords, fall back to ALTER ROLE or a ConnectionOpened interceptor, and know why UsePhysicalConnectionInitializer silently loses its SET.

NUnit 5.0.0 makes Assert.ThrowsAsync, CatchAsync and DoesNotThrowAsync truly asynchronous. Forget the await and the assertion never runs. Here is what breaks, what the NUnit.Analyzers NUnit2059 rule catches, and the other NUnit 5 changes to check before upgrading.

In a workflow, your code decides the next step and the model fills in each step. In an agent, the model decides the next step and your code only executes it. That one question (who owns the control flow) determines cost, latency, testability and failure modes. Here is the distinction as Anthropic, Microsoft Agent Framework and LangGraph define it, with the same task built both ways in Python against claude-haiku-4-5 and claude-sonnet-5-5.

Check IsCompleted first and read the result through GetAwaiter().GetResult(), which costs 0 bytes. Only fall back to blocking when the ValueTask is still pending, and do that with a cached event and UnsafeOnCompleted instead of AsTask(), which allocates 72 to 208 bytes per call. Measured on .NET 10 and .NET 11 RC1.

Microsoft Agent Framework .NET 1.23.0 honors assignments to FunctionInvocationContext.Function, so middleware can redirect a tool call to a different AIFunction. A new WrapWithPendingMiddleware helper keeps the rest of the chain in the loop.

EF.Constant inlines a captured value as a SQL literal, EF.Parameter turns a literal into a SQL parameter. Keep EF Core's defaults, use EF.Parameter to stop dynamically built expression trees from recompiling on every call, and use EF.Constant only for a value with a handful of distinct values whose data is skewed enough to need its own plan.

material_ui 1.3.0 and cupertino_ui 1.1.0 use an annotation Flutter 3.44 does not export. Both are retracted, but a lockfile keeps them. Downgrade, then upgrade, to land on 1.2.0 and 1.0.2.

Volatile.Read is an acquire load of one location. Volatile.ReadBarrier, new in .NET 10, is a fence that gives every earlier read acquire semantics. Use Volatile.Read for flags and published references, and ReadBarrier when you need a batch of plain or non-atomic reads to complete before the next memory access, as in a seqlock.