What problem does it solve? Upgrading a project from .NET 9 to .NET 10 introduces dozens of breaking changes across the compiler, runtime, SDK, ASP.NET Core, EF Core, and cryptography APIs. This Skill provides a systematic, step-by-step workflow that identifies which changes apply to your project and supplies concrete fixes, so nothing is missed during the migration. ## Core Features & Use Cases - Guided six-step migration workflow: Assess the project, update the TargetFramework to net10.0, resolve build errors, address behavioral changes, update infrastructure (Dockerfiles, CI/CD, global.json), and verify with builds and tests. - Technology-specific reference documents: Ten detailed references covering C# 14 compiler changes, core libraries, SDK/MSBuild, ASP.NET Core, EF Core, cryptography, extensions/hosting, serialization/networking, WinForms/WPF, and containers/interop — loaded selectively based on what the project uses. - Concrete fix patterns: Includes before/after code for SYSLIB0058–SYSLIB0062 obsoletions, the C# 14 field and extension keywords, span overload resolution, Microsoft.OpenApi v2 changes, System.Linq.Async migration, and Sqlite DateTimeOffset behavior. - Use Case: You update your build server to the .NET 10 SDK and your solution suddenly fails with CS9272 errors, NU1510 warnings, and OpenAPI compilation errors. This Skill walks you through each failure category with the exact fix. ## Quick Start Migrate my solution at ./src/MyApp.sln from .NET 9 to .NET 10 and fix all resulting build errors and breaking changes.
