How to make SlowCheetah work with class libraries and services, apart from executables

Add a App.Base.Config which is the base for all configs and the below lines would ensure on build the specific environment gets copied to the App.config.

Just add the below lines to end of .csProj file where you need SlowCheetah support:

<Import Project="$(SlowCheetahTargets)" Condition="Exists('$(SlowCheetahTargets)')" Label="SlowCheetah" />
  <Import Project="..\packages\Microsoft.VisualStudio.SlowCheetah.3.0.61\build\Microsoft.VisualStudio.SlowCheetah.targets" Condition="Exists('..\packages\Microsoft.VisualStudio.SlowCheetah.3.0.61\build\Microsoft.VisualStudio.SlowCheetah.targets')" />
  <Import Project="$(MSBuildExtensionsPath32)\Microsoft\VisualStudio\v$(VisualStudioVersion)\WebApplications\Microsoft.WebApplication.targets" />
  <Target Name="BeforeBuild">
    <TransformXml Source="App.Base.config" Transform="App.$(Configuration).config" Destination="App.config" />
  </Target>