npx claudepluginhub dotnet/skills --plugin dotnet-upgradeThis skill uses the workspace's default tool permissions.
Migrate a .NET 10 project or solution to .NET 11, systematically resolving all breaking changes. The outcome is a project targeting `net11.0` that builds cleanly, passes tests, and accounts for every behavioral, source-incompatible, and binary-incompatible change introduced in .NET 11.
Guides Next.js Cache Components and Partial Prerendering (PPR) with cacheComponents enabled. Implements 'use cache', cacheLife(), cacheTag(), revalidateTag(), static/dynamic optimization, and cache debugging.
Migrates code, prompts, and API calls from Claude Sonnet 4.0/4.5 or Opus 4.1 to Opus 4.5, updating model strings on Anthropic, AWS, GCP, Azure platforms.
Automates semantic versioning and release workflow for Claude Code plugins: bumps versions in package.json, marketplace.json, plugin.json; verifies builds; creates git tags, GitHub releases, changelogs.
Migrate a .NET 10 project or solution to .NET 11, systematically resolving all breaking changes. The outcome is a project targeting net11.0 that builds cleanly, passes tests, and accounts for every behavioral, source-incompatible, and binary-incompatible change introduced in .NET 11.
Note: .NET 11 is currently in preview. This skill covers breaking changes documented through Preview 1. It will be updated as additional previews ship.
TargetFramework from net10.0 to net11.0net11.0 and builds cleanly — migration is done| Input | Required | Description |
|---|---|---|
| Project or solution path | Yes | The .csproj, .sln, or .slnx entry point to migrate |
| Build command | No | How to build (e.g., dotnet build, a repo build script). Auto-detect if not provided |
| Test command | No | How to run tests (e.g., dotnet test). Auto-detect if not provided |
| Project type hints | No | Whether the project uses ASP.NET Core, EF Core, Cosmos DB, etc. Auto-detect from PackageReferences and SDK attributes if not provided |
Answer directly from the loaded reference documents for information about .NET 11 breaking changes. You may inspect the local repository (project/solution files, source code, configuration, build/test scripts) as needed to determine which changes apply. Do not fetch web pages or other external sources for breaking change information — the loaded references are the authoritative source. Focus on identifying which breaking changes apply and providing concrete fixes.
Commit strategy: Commit at each logical boundary — after updating the TFM (Step 2), after resolving build errors (Step 3), after addressing behavioral changes (Step 4), and after updating infrastructure (Step 5). This keeps each commit focused and reviewable.
.sln/.slnx files, or individual .csproj files.dotnet --version to confirm the .NET 11 SDK is installed. If it is not, stop and inform the user.Microsoft.NET.Sdk.Web → ASP.NET Core; Microsoft.NET.Sdk.WindowsDesktop with <UseWPF> or <UseWindowsForms> → WPF/WinFormsMicrosoft.EntityFrameworkCore.* → EF Core; Microsoft.EntityFrameworkCore.Cosmos → Cosmos DB providerNamedPipeClientStream usage with SafePipeHandle → SYSLIB0063 constructor obsoletion relevantdotnet build --no-incremental or delete bin/obj) on the current net10.0 target to establish a clean baseline. Record any pre-existing warnings.In each .csproj (or Directory.Build.props if centralized), change:
<TargetFramework>net10.0</TargetFramework>
to:
<TargetFramework>net11.0</TargetFramework>
For multi-targeted projects, add net11.0 to <TargetFrameworks> or replace net10.0.
Update all Microsoft.Extensions.*, Microsoft.AspNetCore.*, Microsoft.EntityFrameworkCore.*, and other Microsoft package references to their 11.0.x versions. If using Central Package Management (Directory.Packages.props), update versions there.
Run dotnet restore. Fix any restore errors before continuing.
Run dotnet build. Capture all errors and warnings — these will be addressed in Step 3.
Load reference documents based on the project's technology areas:
| Reference file | When to load |
|---|---|
references/csharp-compiler-dotnet10to11.md | Always (C# 15 compiler breaking changes) |
references/core-libraries-dotnet10to11.md | Always (applies to all .NET 11 projects) |
references/sdk-msbuild-dotnet10to11.md | Always (SDK and build tooling changes) |
references/efcore-dotnet10to11.md | Project uses Entity Framework Core (especially Cosmos DB provider) |
references/cryptography-dotnet10to11.md | Project uses cryptography APIs or targets macOS |
references/runtime-jit-dotnet10to11.md | Deploying to older hardware or embedded devices |
Work through each build error systematically. Common patterns:
C# 15 Span collection expression safe-context — Collection expressions of Span<T>/ReadOnlySpan<T> type now have declaration-block safe-context. Code assigning span collection expressions to variables in outer scopes will error. Use array type or move the expression to the correct scope.
ref readonly delegates/local functions need InAttribute — If synthesizing delegates from ref readonly-returning methods or using ref readonly local functions, ensure System.Runtime.InteropServices.InAttribute is available.
nameof(this.) in attributes — Remove this. qualifier; use nameof(P) instead of nameof(this.P).
with() in collection expressions (C# 15) — with(...) is now treated as constructor arguments, not a method call. Use @with(...) to call a method named with.
Dynamic &&/|| with interface operand — Interface types as left operand of &&/|| with dynamic right operand now errors at compile time. Cast to concrete type or dynamic.
EF Core Cosmos sync I/O removal — ToList(), SaveChanges(), etc. on Cosmos provider always throw. Convert to async equivalents.
SYSLIB0063: NamedPipeClientStream isConnected parameter obsoleted — The constructor overload taking bool isConnected is obsoleted. Remove the isConnected argument and use the new 3-parameter constructor. Projects with TreatWarningsAsErrors will fail to build.
when switch-expression-arm parsing — (X.Y) when is now parsed as a constant pattern with a when clause instead of a cast expression, which can cause existing code to fail to compile or change meaning. Review switch expressions using when and adjust syntax as needed.
These changes compile successfully but alter runtime behavior. Review each one and determine impact:
DeflateStream/GZipStream empty payload — Now writes headers and footers even for empty payloads. If your code checks for zero-length output, update the check.
MemoryStream maximum capacity — Maximum capacity updated and exception behavior changed. Review code that creates large MemoryStreams or relies on specific exception types.
TAR header checksum validation — TAR-reading APIs now verify checksums. Corrupted or hand-crafted TAR files may now fail to read.
ZipArchive.CreateAsync eager loading — ZipArchive.CreateAsync eagerly loads entries. May affect memory usage for large archives.
Environment.TickCount consistency — Made consistent with Windows timeout behavior. Code relying on specific tick count behavior may need adjustment.
DSA removed from macOS — DSA cryptographic operations throw on macOS. Use a different algorithm (RSA, ECDSA).
Japanese Calendar minimum date — Minimum supported date corrected. Code using very early Japanese Calendar dates may be affected.
Minimum hardware requirements — x86/x64 baseline moved to x86-64-v2; Windows Arm64 requires LSE. Verify deployment targets meet requirements.
Mono launch target for .NET Framework — No longer set automatically. If using Mono for .NET Framework apps on Linux, specify explicitly.
Dockerfiles: Update base images from 10.0 to 11.0:
# Before
FROM mcr.microsoft.com/dotnet/sdk:10.0 AS build
FROM mcr.microsoft.com/dotnet/aspnet:10.0
# After
FROM mcr.microsoft.com/dotnet/sdk:11.0 AS build
FROM mcr.microsoft.com/dotnet/aspnet:11.0
CI/CD pipelines: Update SDK version references. If using global.json, update the sdk.version in your existing file while preserving other keys (such as rollForward and test configuration):
{
"sdk": {
- "version": "10.0.100",
- "rollForward": "latestFeature"
+ "version": "11.0.100-preview.1",
+ "rollForward": "latestFeature"
},
"otherSettings": {
"...": "..."
}
}
Hardware deployment targets: Verify all deployment targets meet the updated minimum hardware requirements (x86-64-v2 for x86/x64, LSE for Windows Arm64).
dotnet build --no-incrementaldotnet testThe references/ folder contains detailed breaking change information organized by technology area. Load only the references relevant to the project being migrated:
| Reference file | When to load |
|---|---|
references/csharp-compiler-dotnet10to11.md | Always (C# 15 compiler breaking changes) |
references/core-libraries-dotnet10to11.md | Always (applies to all .NET 11 projects) |
references/sdk-msbuild-dotnet10to11.md | Always (SDK and build tooling changes) |
references/efcore-dotnet10to11.md | Project uses Entity Framework Core (especially Cosmos DB provider) |
references/cryptography-dotnet10to11.md | Project uses cryptography APIs or targets macOS |
references/runtime-jit-dotnet10to11.md | Deploying to older hardware or embedded devices |