"Stuart" gives the system a lot of structure and flexibility.  It lets us maintain the build process consistently in a cross platform way and allows platforms to use python instead of shell scripting.  This takes advantage of our investments in dependency management, optimized submodule management, logging, plugins, etc.  OVMF is a pretty simple "platformbuild" but it still get many advantages (from my pov).

We have talked about Stuart a few times at design meetings (so you can see some of the slides that have been uploaded) and willing to discuss more if you have specific questions.

Thanks
Sean