Node Version Manager is a tool for
switching between releases of node. This is useful
for testing your code before deployment, or testing your open source
code against different versions of node. There have been API changes
lately so it's worth having a sanity check against major releases.
Installing a specific version works like this:
nvm install v0.1.91
nvm is actually a bash script, much like
kiwi (by the same author). That means it should work on unix-like systems without too much trouble.
TJ Holowaychuk wrote a blog post with more
details on nvm: Node Version Manager