dotnet-multi-targeting

To configure .NET multi-targeting, you use specific .csproj patterns to target multiple Target Framework Monikers (TFMs) simultaneously, applying conditional references and platform-specific settings to ensure shared libraries build correctly across different runtimes.

The best way to backport C# language features and BCL APIs is by using polyfill strategies. You can utilize tools like PolySharp and SimonCropp/Polyfill to seamlessly bridge API compatibility gaps across different .NET runtime versions.

Conditional compilation in .NET multi-targeting works by using #if directives and TFM-specific source files. This allows developers to isolate runtime or platform differences, enabling conditional code execution optimized for each targeted framework.

Yes, you can validate API compatibility across multiple .NET targets. By enabling the EnablePackageValidation setting and using the ApiCompat tool, you ensure cross-framework API consistency and prevent breaking changes between different targeted runtimes.

You need polyfills when targeting both net8.0 and net10.0 if you want to use newer C# features in the older runtime. Polyfills bridge the compatibility gap, ensuring your shared .NET library runs seamlessly with feature parity across both frameworks.