dotnet-upgrade
By dotnet
Automate upgrading .NET projects across versions 8→9→10→11 by updating TargetFrameworks, fixing C# compiler issues, ASP.NET Core/EF Core breaking changes, adapting CI/CD/Dockerfiles; enable nullable reference types project-wide; resolve Native AOT warnings; migrate Thread.Abort to cooperative cancellation.
Component Overview
Install
npx claudepluginhub dotnet/skills --plugin dotnet-upgradeComponent Details
Skills (6)
Make .NET projects compatible with Native AOT and trimming by systematically resolving IL trim/AOT analyzer warnings. USE FOR: making projects AOT-compatible, fixing trimming warnings, resolving IL warnings (IL2026, IL2070, IL2067, IL2072, IL3050), adding DynamicallyAccessedMembers annotations, enabling IsAotCompatible. DO NOT USE FOR: publishing native AOT binaries, optimizing binary size, replacing reflection-heavy libraries with alternatives. INVOKES: no tools — pure knowledge skill.
Migrate a .NET 10 project or solution to .NET 11 and resolve all breaking changes. This is a MIGRATION skill — use it when upgrading from .NET 10 to .NET 11, NOT for writing new programs. USE FOR: upgrading TargetFramework from net10.0 to net11.0, fixing build errors after updating the .NET 11 SDK, resolving source-breaking and behavioral changes in .NET 11 runtime, C# 15 compiler, and EF Core 11, adapting to updated minimum hardware requirements (x86-64-v2, Arm64 LSE), and updating CI/CD pipelines and Dockerfiles for .NET 11. DO NOT USE FOR: .NET Framework migrations, upgrading from .NET 9 or earlier, greenfield .NET 11 projects, or cosmetic modernization unrelated to the upgrade. NOTE: .NET 11 is in preview. Covers breaking changes through Preview 1.
Migrate a .NET 8 project to .NET 9 and resolve all breaking changes. USE FOR: upgrading TargetFramework from net8.0 to net9.0, fixing build errors after updating the .NET 9 SDK, resolving behavioral changes in .NET 9 / C# 13 / ASP.NET Core 9 / EF Core 9, replacing BinaryFormatter (now always throws), resolving SYSLIB0054-SYSLIB0057, adapting to params span overload resolution, fixing C# 13 compiler changes, updating HttpClientFactory for SocketsHttpHandler, and resolving EF Core 9 migration/Cosmos DB changes. DO NOT USE FOR: .NET Framework migrations, upgrading from .NET 7 or earlier, greenfield .NET 9 projects, or cosmetic modernization unrelated to the upgrade.
Migrate a .NET 9 project or solution to .NET 10 and resolve all breaking changes. USE FOR: upgrading TargetFramework from net9.0 to net10.0, fixing build errors after updating the .NET 10 SDK, resolving source and behavioral changes in .NET 10 / C# 14 / ASP.NET Core 10 / EF Core 10, updating Dockerfiles for Debian-to-Ubuntu base images, resolving obsoletion warnings (SYSLIB0058-SYSLIB0062), adapting to SDK/NuGet changes (NU1510, PrunePackageReference), migrating System.Linq.Async to built-in AsyncEnumerable, fixing OpenApi v2 API changes, cryptography renames, and C# 14 compiler changes (field keyword, extension keyword, span overloads). DO NOT USE FOR: .NET Framework migrations, upgrading from .NET 8 or earlier (use migrate-dotnet8-to-dotnet9 first), greenfield .NET 10 projects, or cosmetic modernization. LOADS REFERENCES: csharp-compiler, core-libraries, sdk-msbuild (always); aspnet-core, efcore, cryptography, extensions-hosting, serialization-networking, winforms-wpf, containers-interop (selective).
Enable nullable reference types in a C# project and systematically resolve all warnings. USE FOR: adopting NRTs in existing codebases, file-by-file or project-wide migration, fixing CS8602/CS8618/CS86xx warnings, annotating APIs for nullability, cleaning up null-forgiving operators, upgrading dependencies with new nullable annotations. DO NOT USE FOR: projects already fully migrated with zero warnings (unless auditing suppressions), fixing a handful of nullable warnings in code that already has NRTs enabled, suppressing warnings without fixing them, C# 7.3 or earlier projects. INVOKES: Get-NullableReadiness.ps1 scanner script.
Guides migration of .NET Framework Thread.Abort usage to cooperative cancellation in modern .NET. USE FOR: modernizing code that calls Thread.Abort, catching ThreadAbortException, replacing Thread.ResetAbort, replacing Thread.Interrupt for thread termination, resolving PlatformNotSupportedException or SYSLIB0006 after retargeting to .NET 6+, migrating ASP.NET Response.End or Response.Redirect(url, true) which internally call Thread.Abort. DO NOT USE FOR: code that only uses Thread.Join, Thread.Sleep, or Thread.Start without any abort, interrupt, or ThreadAbortException usage — these APIs work identically in modern .NET and need no migration. Also not for projects staying on .NET Framework, or Thread.Abort usage inside third-party libraries you do not control.
README
.NET Agent Skills
This repository contains the .NET team's curated set of core skills and custom agents for coding agents. For information about the Agent Skills standard, see agentskills.io.
What's Included
| Plugin | Description |
|---|---|
| dotnet | Collection of core .NET skills for handling common .NET coding tasks. |
| dotnet-data | Skills for .NET data access and Entity Framework related tasks. |
| dotnet-diag | Skills for .NET performance investigations, debugging, and incident analysis. |
| dotnet-msbuild | Comprehensive MSBuild and .NET build skills: failure diagnosis, performance optimization, code quality, and modernization. |
| dotnet-nuget | NuGet and .NET package management: dependency management and modernization. |
| dotnet-upgrade | Skills for migrating and upgrading .NET projects across framework versions, language features, and compatibility targets. |
| dotnet-maui | Skills for .NET MAUI development: environment setup, diagnostics, and troubleshooting. |
| dotnet-ai | AI and ML skills for .NET: technology selection, LLM integration, agentic workflows, RAG pipelines, MCP, and classic ML with ML.NET. |
| dotnet-template-engine | .NET Template Engine skills: template discovery, project scaffolding, and template authoring. |
| dotnet-test | Skills for running, diagnosing, and migrating .NET tests: test execution, filtering, platform detection, and MSTest workflows. |
| dotnet-aspnet | ASP.NET Core web development skills including middleware, endpoints, real-time communication, and API patterns. |
Installation
🚀 Plugins - Copilot CLI / Claude Code
- Launch Copilot CLI or Claude Code
- Add the marketplace:
/plugin marketplace add dotnet/skills - Install a plugin:
/plugin install <plugin>@dotnet-agent-skills - Restart to load the new plugins
- View available skills:
/skills - View available agents:
/agents - Update plugin (on demand):
/plugin update <plugin>@dotnet-agent-skills
VS Code / VS Code Insiders (Preview)
[!IMPORTANT]
VS Code plugin support is a preview feature and subject to change. You may need to enable it first.
// settings.json
{
"chat.plugins.enabled": true,
"chat.plugins.marketplaces": ["dotnet/skills"]
}
Once configured, type /plugins in Copilot Chat or use the @agentPlugins filter in Extensions to browse and install plugins from the marketplace.
Codex CLI
Skills in this repository follow the agentskills.io open standard and are compatible with OpenAI Codex.
Install individual skills using the skill-installer CLI with the GitHub URL:
$ skill-installer install https://github.com/dotnet/skills/tree/main/plugins/<plugin>/skills/<skill-name>
⚡ Agentic Workflows
Some plugins include GitHub Agentic Workflow templates for CI/CD automation:
- Install the
gh awCLI extension - Copy the desired workflow
.mdfiles and theshared/directory to your repository's.github/workflows/ - Compile and commit:
gh aw compile - Commit both the
.mdand generated.lock.ymlfiles
Contributing
See CONTRIBUTING.md for contribution guidelines and how to add a new plugin.
License
See LICENSE for details.
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