Installation:

If you have an existing Haxe install, you will need to nuke it from orbit:

sudo rm -rf /usr/lib/haxe
sudo rm -rf /usr/lib/neko
sudo rm /usr/lib/libneko.dylib
sudo rm /usr/bin/haxe*
sudo rm /usr/bin/neko*

And then:

git clone https://github.com/dpeek/hvm.git ~/.hvm
echo "source ~/.hvm/hvm.sh" >> ~/.profile
source ~/.profile
hvm install

What does it do?

Running hvm install creates these symlinks:

sudo ln -sf ~/.hvm/haxe.sh /usr/bin/haxe
sudo ln -sf ~/.hvm/haxelib.sh /usr/bin/haxelib
sudo ln -sf ~/.hvm/neko.sh /usr/bin/neko
sudo ln -sf ~/.hvm/nekotools.sh /usr/bin/nekotools
sudo ln -sf ~/.hvm/nekoc.sh /usr/bin/nekoc
sudo ln -sf ~/.hvm/nekoml.sh /usr/bin/nekoml

Each of those scripts sources config.sh, which figures out which binary to use.

The config sources ~/.hvm/versions.sh, then ~/.hvm/current.sh and then ./hvmrc if it exists. The first defines default versions, the second defines the currently selected global versions (as set with hvm use) and the third allows projects to specify specific versions to use.

The config script uses the versions to determine the path to the right install, located in ~/.hvm/versions/$(neko|haxe|haxelib)/$version. If that path does not exist, hvm will install it.

Stable versions of Neko are installed from the here while dev versions are installed from here.

Stable versions of Haxe are installed from the here while dev versions are installed from here.

Stable versions of Haxelib are installed from the here while dev versions are installed from here.

To set the current global version in ~/.hvm/current.sh, run:

hvm use $tool $version

Where $tool is one of neko, haxe or haxelib and $version is either dev for the latest development release, or a released version. An error will be printed if you specify a version that does not exist.

If you run hvm use $tool latest the currently installed dev version of $tool will be reinstalled to ensure you are running the most recent dev release.

Important notes

The 2.0.0 OS X release of Neko on http://nekovm.org is built for 32 bit. The Haxe compiler uses Neko shared libraries for certain kinds of Regex matching at macro time. However, stable Haxe releases for OS X are now 64bit (since 3.0.0) meaning this bridging is not possible with the 2.0.0 release of Neko. For this reason it is recommended to use the dev version of Neko with Haxe 3.x releases (this is the default in ~/.hvm/versions.sh)

Complicating matters further, before Haxe 3.0.0 Haxelib was distributed as a compiled 32bit Neko binary, so Haxe 2.x releases will not work with Neko dev. For this reason you will need to use a stable release of Neko with 2.x releases of Haxe.

Simple, really.