To install Ruby you will first need to install the libyaml from source
To install libyaml do the following: 1. change into the source directory

cd libyaml-0.2.5

2. Run the bootstrap script

./bootstrap

3. Run configure script with prefix set to /home/.hub_local

/configure --prefix=/home/.hub_local
make
make install

That it for the libyaml prereq. Next need to download the source code for Ruby here
To compile first need to set the following environment variables

export CPPFLAGS="-I/home/.hub_local/include"
export LDFLAGS=-L/home/.hub_local/lib

Then change the directory into the Ruby source folder and run the configure script

./configure --prefix=/home/.hub_local
make
make install

That should be it.