Writing your language's build system in itself shouldn't be any worse than writing your language's compiler in itself. The GHC folks are rewriting their jungle

Writing your language's build system in itself shouldn't be any worse than writing your language's compiler in itself. The GHC folks are rewriting their jungle of recursive Makefiles in Shake, a Haskell-based build system. I think you only need the ability to build a cross compiler for this to work.