Grunt is just generally a helpful little task runner and good for automating many things in general web development - running tests, concatenation / minification, linting, HTML / CSS / JS preprocessing and so on, if that floats your boat. It really is worth giving it a go.
Well, makefiles have worked fine for me so far.
You might like Jake, then. It's a Node.js version of Rake (which is a ruby version of make).
Maybe that's where the confusion was. I was talking about browser development. Thanks.