That's the kind of thing I was thinking about. Do they exist? One example that someone mentioned in a sibling comment is Autosetup, which apparently uses Tcl i

That's the kind of thing I was thinking about. Do they exist? One example that someone mentioned in a sibling comment is Autosetup, which apparently uses Tcl instead of posix shell + m4. An interesting idea... Tcl is one of those languages that's small enough that it's feasible to include a copy of the interpreter together with the build scripts.