A workmate floated the idea of using rake as a build system for a non-ruby project. Is it possible to extend rake to compliment other languages where the autoconf toolset would usually be used?
There are examples of this, like buildr, the drop in-replacement for maven (for java) that is built on top of rake. There's also raven for java.
I use it to deploy (Capistrano) on several non-Rails projects. One Java (servlet) and several static HTML sites.
Very handy.
You can find how to use Rake as an easy replacement for Makefile in the manual...
I use it almost exlusevely for build that I write myself... If you use Java better choice would be Ant and Maven - they have a lot of code behind them... But, as for me, you have to be a little brainf*ed to program in XML, so I often use Rake for many task, and invoke it from Ant/Maven, like that:
<target name="custom_task">
<exec executable="/usr/bin/env">
<arg value="rake"/>
<arg value="some-task"/>
<arg value="param" />
</exec>
</target>
It may not be super efficient, especially if you have to run anything on the JVM it can't use Ant's, so it is not the best idea... I haven't tried JRuby, maybe it would be worth trying... But for other task - filehandling, doing something with text files, etc. it works really nice for me :-)
I use it to compile Flex applications. I've written wrappers around the Flex SDK command line tools -- it's easy to do for any tool chain that can be called from the command line.