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

Aspire 13.6.4 stops a single timed-out or HTTP 504 DCP create call from sending a resource to FailedToStart, and exposes three DcpPublisher timeouts you can raise on slow CI runners.

A plugin hook fails with "Failed to run: Plugin directory does not exist" when the directory your session loaded the plugin from is gone: an update past the 14-day orphan window, a claude.ai sync that moved the folder to .trash, or a --plugin-dir you moved. Run /reload-plugins, read its summary line, and know which cases need a restart. Checked against Claude Code 2.1.310.

Lock one Flutter route to landscape or portrait with SystemChrome.setPreferredOrientations without breaking the rest of the app: a stack-based lock that survives pushReplacement and restores on pop, why the empty list is the wrong reset, why iPad multitasking and Android 16 large screens ignore the lock, and what UIRequiresFullScreen means after iPadOS 26 and the iOS 27 SDK. Tested on Flutter 3.47.8 with Dart 3.13.7 and Xcode 27.1.

Put a discriminator field in the JSON, switch on it in a factory on the sealed base, and switch on the subtype to write it back. Three working versions on Dart 3.13.7: hand-written pattern matching, json_serializable 6.15.2, and Freezed 4.0.3 with unionKey and fallbackUnion, plus the gotchas each one hides.

Microsoft Agent Framework 1.26.0 makes MapAGUIServer resolve the keyed AIAgent, its AgentSessionStore, and the isolation key provider per request, and adds a selector overload that picks the agent from the HttpContext.

Model followers and following on a single User entity in EF Core 11: what the convention builds, why SQL Server quietly turns one join foreign key into ClientCascade, how to map an explicit Follow join entity with a timestamp, and how to delete a user without error 547 or 1785.

depend_on_referenced_packages fires when a file imports or exports a package that is not listed in your own pubspec.yaml, even if it resolves through another dependency. Here is exactly what the rule checks on Dart 3.12.2 and Flutter 3.44.8, why transitive imports are a real bug, and how to fix each variant.

A claude -p run on Opus with an API key gives up after three consecutive 529s, about 1.5 seconds of backoff, no matter what CLAUDE_CODE_MAX_RETRIES says. Add --fallback-model, set CLAUDE_CODE_RETRY_WATCHDOG=1 with a max wait, or widen the 529 backoff with the OVERLOADED_RETRY delay variables. Checked against Claude Code 2.1.309.

Replace the deprecated Color.withOpacity, opacity, value, red, green, blue and alpha with withValues, .a/.r/.g/.b and toARGB32. What dart fix rewrites for you, the four getters it leaves behind, why exact color assertions and Map<Color, T> lookups break after the swap, and how withOpacity silently drops Display P3. Measured on Flutter 3.44.8 with Dart 3.12.2.

Replace hand-rolled WidgetsBindingObserver lifecycle code with AppLifecycleListener: the callback mapping, the state machine it enforces, the new hidden state that breaks exhaustive switches, desktop exit requests, and the test that suddenly asserts. Tested on Flutter 3.44.8 with Dart 3.12.2.