Package	Purpose
Stride.Build.Sdk	Base SDK for all projects. Platform detection, target frameworks, graphics API multi-targeting, assembly processor, native dependencies.
Stride.Build.Sdk.Editor	Composes `Stride.Build.Sdk`. Adds editor framework properties.
Stride.Build.Sdk.Tests	Composes `Stride.Build.Sdk.Editor`. Adds xunit, test infrastructure, launcher code, asset compilation.

Current Import Mode: Direct Imports

All Stride projects currently import these SDK files directly from source rather than via NuGet packages:

<Project>
  <Import Project="$([MSBuild]::GetDirectoryNameOfFileAbove($(MSBuildProjectDirectory), 'Directory.Build.props'))/sdk/Stride.Build.Sdk/Sdk/Sdk.props" />
  <!-- project content -->
  <Import Project="$(StrideRoot)sources/sdk/Stride.Build.Sdk/Sdk/Sdk.targets" />
</Project>

Why: MSBuild SDK resolution (Sdk="Stride.Build.Sdk") requires the packages to be pre-built and cached in ~/.nuget/packages/ before the solution can open. Direct imports load files straight from the source tree — no pre-build step, and changes to .targets files take effect immediately.

Why two different import mechanisms:

The props import uses GetDirectoryNameOfFileAbove because $(StrideRoot) is not yet set when the first import runs (it is set by sources/Directory.Build.props, which is auto-discovered only after Microsoft.NET.Sdk loads Microsoft.Common.props — which happens inside Sdk.props).
The targets import uses $(StrideRoot) because by that point the full SDK chain has loaded and $(StrideRoot) is available.

The SDK internal cross-references (Stride.Build.Sdk.Editor -> Stride.Build.Sdk, etc.) also use $(MSBuildThisFileDirectory)-relative paths for the same reason.

Reverting to Full SDK Mode

See the "Reverting to full-SDK style" section in docs/build/SDK-GUIDE.md for complete instructions.

Building the SDK Packages

The packages are only needed when testing NuGet package distribution or reverting to full SDK mode:

dotnet build sources/sdk/Stride.Build.Sdk.slnx

For detailed documentation, see docs/build/SDK-GUIDE.md.