I wrote a simple lib to help you organize your projects a bit, inspired by rake.
Import it as a lib and build your nakefile like the regular nimrod file it is. You could just do this for all your uses, or run the nakefile that comes with nake which will attempt to build and install a binary nake. All the binary does is forward its commands to nimrod c -r nakefile so that nake test will recompile the nakefile in the current dir and run it with your args.
https://gist.github.com/3607822
*written and tested for 0.8.15, I can say with some surety that it will not work on 0.8.14 or lower
You can use babel to install or update to this version.
what's the "right" way to update nake using nimble?
The same way you install it, run nimble install nake to get the latest stable version.
Also, it would be nice if nake had a "-v/--version" switch so we could know what version we had installed.
Not sure if this makes much sense since nake gets built into your nakefiles, so if you don't recompile too often you could have lying around nake binaries using different nake versions, and that's ok too. You can ask nimble what's the latest version you have active for new builds:
$ nimble path nake
/Users/gradha/.nimble/pkgs/nake-1.6
Finally, could nake periodically check for new versions
This could be more useful as a nimble feature, since it would also apply to every other nim package.