Fix: The method 'getInvocation' isn't defined for the type 'DartObjectImpl'
build_runner fails to compile because source_gen 3.1.0 or 4.0.0 calls an analyzer API removed in analyzer 8.4.0. Upgrade the generator that pins source_gen below 4.0.1.
Blog
Page 23 of 102
PreModelSwitch: Claude Code Can Now Veto a Model Change
Claude Code 2.1.251 adds PreModelSwitch and PostModelSwitch hook events. The matcher fires on the canonical name of the model you are switching to, and exit code 2 cancels the switch.
Fix: 23505: duplicate key value violates unique constraint on a concurrent EF Core insert
The check-then-insert in your handler is not atomic. Catch PostgresException with SqlState 23505, or collapse the whole thing into one INSERT ... ON CONFLICT statement. EnableRetryOnFailure will not help.
Fix: CREATE DATABASE permission denied in database 'master' when running dotnet ef database update
EF Core's Migrate() always checks whether the database exists and creates it if not, from a hardcoded master connection. Grant CREATE ANY DATABASE, fix the login's access to the existing database, or ship an idempotent SQL script instead.
Fix: Model building is not supported when publishing with NativeAOT in a .NET MAUI iOS build
iOS builds set DynamicCodeSupport=false, so EF Core refuses to build the model even though you never enabled NativeAOT. Ship a compiled model plus precompiled queries, or turn the interpreter back on.
Stateful vs Stateless MCP Servers: What Actually Breaks When the Session Goes Away
Protocol revision 2026-07-28 deleted Mcp-Session-Id, the initialize handshake, resources/subscribe, ping, logging/setLevel and SSE resumability. An automated survey of 1000 open source MCP servers found 90% reference the session ID nowhere. Here is what the other 10% has to rewrite, with verified code on @modelcontextprotocol/server 2.0.0.
Claude Code 2.1.251 Closes Four Ways Around the Permission Check
A symlink swapped after the check, deny rules that stopped applying through a symlinked search path, a marketplace command pointing outside its plugin, and a workflow script read before approval. Four fixes in one release, all the same bug.
Fix: CA1070 "Do not declare event fields as virtual"
CA1070 fires on virtual field-like events. Drop the virtual, keep the event non-virtual, and let derived classes override a protected virtual OnXxx raiser instead.
Fix: Doesn't support required ABI when installing a .NET MAUI Android app
The APK has no native library for the device's CPU. Since .NET 9 the default Android RuntimeIdentifiers are 64-bit only, so the fix is to set RuntimeIdentifiers explicitly. Covers ADB0020, XA0036, NETSDK1083, the ABI to RID mapping, the Play Console wording, and why the four-RID snippet everyone copies breaks on .NET 11.
Fix: failed to resolve source metadata for mcr.microsoft.com/dotnet/aspnet
BuildKit cannot read the manifest for your base image. Check the tag exists, repair the Docker credential helper, open both MCR endpoints, then pre-pull for offline builds.