If your build reaches the point where you feel you need a wide variety of strange "make" constructs, you don’t necessarily need a new build system; you need to be smarter about the setup. For example: do everything in two phases, where the more “magical” version generates a less magical, verbose, static makefile with more rules that are relatively easy to understand and debug.

And, besides: a huge impediment to improving the state of build systems is that new build mechanisms won’t be installed on most platforms by default. If you must explore new ways to build, be sure to implement that in terms of what is already there (Perl/Python/whatever) and make sure to ship your new build system WITH your code.

When I download some "neat-project-1.0.tar.gz", the last thing I want is to have to futz with setting up your special build system that Probably Nothing Else uses or will ever use. If it’s not in the tarball, I will already lose a lot of interest; I know most things can "configure, make, make install" in minutes but I don’t know how much time will be wasted installing whizbang-build-0.1 first and I probably won’t even try.