Going through MSBuild solution parser I see there is an Evaluator that initiates the build by parsing the solution (see also language interpretation parts). I'm curious if there is any way to extend MSBuild to implement a different evaluator, one that reads a custom file that serves as the solution file in my project, and build my own project AST.

My options I considered so far are:

• use a valid MSBuild .proj file as my solution file format and then MSBuild can build it as any other valid MSBuild file (sort of how a .csproj file is both the project model file and also a valid MSBuild file)
• use a custom tool that reads my solution file, creates a .proj file and calls MSBuild on the .proj file

I'm looking if there is a way to directly do MSBuild mysolution.file and have it work.