How would you manage the lifecycle and automated build process when some of the projects (C# .csproj projects) are part of the actual build system?
Example: A.csproj is a project that uses MSBuild tasks that are implemented in BuildEnv.csproj. Both projects are part of the same product (meaning, BuildEnv.csproj frequently changes as the product is being developed and not a 3rd party that is rarely updated)