Lmod is not available in Gentoo’s portage. This blog post will document how I got Lmod installed on my Gentoo machine.

First requirement is to install lua. I picked lua 5.2 as I had problem when experimenting with Lua 5.1. To install lua-5.2.3 from portage, run:

# emerge -av =dev-lang/lua-5.2.3

If you have multiple versions of Lua installed, make sure to select this lua 5.2.3 as the default version using eselect:

# eselect lua list
  [1]   5.2
# eselect lua set 1

Lmod depends on 2 lua-libraries: posix and filesystem. Both of these libraries are available on Gentoo as packages dev-lua/luaposix and dev-lua/luafilesystem. However, those lua-packages depends on lua 5.1. So I have to find another way to install the required libraries.

Fortunately, we can use a package manager for Lua modules called LuaRocks. (And it does rock as its name!)

# emerge -av dev-lua/luarocks

After that we can proceed with the installation of the 2 lua-modules:

# luarocks install luaposix; luarocks install luafilesystem
luaposix 34.0.4-1 is now built and installed in /usr/lib64/lua/luarocks
luafilesystem 1.7.0-2 is now built and installed in /usr/lib64/lua/luarocks

Now, you have to make the the lua packages installed by luarocks to be known by lua. Let’s display the package path and shared libraries path:

$ lua -e 'print(package.path)'

$ lua -e 'print(package.cpath)'

Then you need to append LUAROCKS_PREFIX to both LUA_PATH amd LUA_CPATH:

export LUA_PATH="$LUAROCKS_PREFIX/share/lua/5.2/?.lua;$LUAROCKS_PREFIX/share/lua/5.2/?/init.lua;;"
export LUA_CPATH="$LUAROCKS_PREFIX/lib/lua/5.2/?.so;;"

Before we could start building Lmod, there is just one more package needed to be installed.

# emerge -av dev-lang/tcl

Alright, we’re ready to start building Lmod. As of this writing, the latest Lmod version available is 7.8.20. Let’s get the source code and untar it. (I compile the Lmod source code as a non-privileged user.)

$ wget https://github.com/TACC/Lmod/archive/7.8.20.tar.gz
$ tar xzvf 7.8.20.tar.gz
$ cd Lmod-7.8.20

In my case, I picked Lmod to be installed to /opt/lmod/7.8.20 directory:

./configure --prefix=/opt
BASH_ENV is defined both in:
Configure complete, Now do:

    $ make install       # -> A complete install
    $ make pre-install   # -> Install everything but the symbolic link

$ sudo -E make install

I’m using ZSH-shell, and to get lmod loaded when a shell is opened, I need to append the following ine to the ~/.zshrc:

# Source lmod
if [[ -s /opt/lmod/lmod/init/profile ]]; then
  source /opt/lmod/lmod/init/profile

As the last step, let’s verify if the installation is working:

❯❯❯ type module
module is a shell function from /opt/lmod/lmod/init/zsh

❯❯❯ echo $LMOD_CMD

❯❯❯ echo $MODULEPATH

There seems to be a lot work to get Lmod installed, but hey I learned quite a bit during this short journey.