Migrate Dotnet9 To Dotnet10
Migrate a .NET 9 project or solution to .NET 10 and resolve all breaking changes.
Install
npx skills add managedcode/dotnet-skills --skill migrate-dotnet9-to-dotnet10 -g -a claude-code -y- Repository
- managedcode/dotnet-skills500
- Category
- Engineering
- Updated
- 6d ago
- License
- MIT
- Context cost
- Mediumabout 3,000 tokens
- Runs scripts
- No, instructions only
What it does
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).
.NET 9 → .NET 10 Migration
Migrate a .NET 9 project or solution to .NET 10, systematically resolving all breaking changes. The outcome is a project targeting net10.0 that builds cleanly, passes tests, and accounts for every behavioral, source-incompatible, and binary-incompatible change introduced in the .NET 10 release.
When to Use
- Upgrading
TargetFrameworkfromnet9.0tonet10.0 - Resolving build errors or new warnings after updating the .NET 10 SDK
- Adapting to behavioral changes in .NET 10 runtime, ASP.NET Core 10, or EF Core 10
- Updating CI/CD pipelines, Dockerfiles, or deployment scripts for .NET 10
- Migrating from the community
System.Linq.Asyncpackage to the built-inSystem.Linq.AsyncEnumerable
When Not to Use
- The project already targets
net10.0and builds cleanly, migration is done - Upgrading from .NET 8 or earlier, use the
migrate-dotnet8-to-dotnet9skill first to reachnet9.0, then return to this skill for thenet9.0→net10.0migration - Migrating from .NET Framework, that is a separate, larger effort
- Greenfield projects that start on .NET 10 (no migration needed)
Inputs
| 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, WinForms, WPF, containers, etc. Auto-detect from PackageReferences and SDK attributes if not provided |
