I have released subdirmk 0.3.
Recap
Peter Miller's 1997 essay Recursive Make Considered Harmful persuasively argues that it is better to arrange to have a single make invocation with the project's complete dependency tree, rather than the currently conventional $(MAKE) -C subdirectory approach.
However, I have found that actually writing a project's build system in a non-recursive style is not very ergonomic. So with some help and prompting from Mark Wooding, I have made a tool to help.
What's new
I have overhauled and regularised some of the substitution syntaxes. The filenames have changed. And there is a new $-doubling macro help facility.
Status
It's still 0.x. I'm still open to comments about details of syntax and naming. Please make them here on this blog, or by posting to sgo-software-discuss.
But it's looking quite good I think and I intend to call it 1.0 RSN.