In a recent Update, YaST2 was ported to Ruby. So if you are on OpenSuse and want to use yast, you need a working Ruby installation.
Everything not a problem unless you don’t like distributions’ rubies, but trust on rvm and have it installed as root a.k.a. system-wide. Then you might encounter the problem that yast shuts down with no futher warning:
hostname:~ # yast hostname:~ #
This is because yast relies on the two gems ruby-dbus and fast_gettext. Now you have two choices: 1st: Install these in your default gemset and everything will be fine. Or 2nd: Set the system ruby to the default ruby in rvm (and ignore the warnings about missing executables).
Funfact: Since the rvm scripts are only sourced if you are on a login-shell,
sudo yast will still work. But that’s seems rather hacky.