We have a page just for that question! See: Why rerun?
A unix environment and a bash shell. At this time only Mac OS X and Centos Linux have been tested. In theory, rerun could work on a Windows host using a cygwin environment (let us know if you try cygwin).
No. Rerun is a ~700 line shell script and a set of conventions. Most of this project content is documentation. Functionality is delivered through rerun modules. See stubbs to make a module.
Depends:
No, if you are just executing rerun commands. Some amount of shell familiarity is assumed.
Yes, you need to know bash to write modules although a pure bourne shell script will work just fine.
You need a good text editor (e.g., Vim, emacs or Textmate) and a shell.
The stubbs:docs command will generate a unix style manage page for you if you are developing a module.
Users can run "rerun --manual " to see a man page for the given module.
Fun and odd analogies may strike you while getting to know rerun. We want to keep these for posterity. Send us yours!
[10:35pm] gschueler: rerun is like the empty handle for a swiss army knife
[10:35pm] gschueler: with a single tool that lets you build other tools
[5:16pm] honor: rerun is the ice pick for a bigger conversation
[12:42pm] honor: rerun is a script amoeba