Easy_squeakvm is a project mainly written in Shell, it's free.
Small script to build squeakvm from scratch for Pharo
Simple bash / Linux script to build Squeak VM for Pharo. It:
Just clone the repository then ./easy_squeakvm.sh
To clean just remove the out directory.
Look at variables on top of script to customize paths and versions used.
Check: http://book.pharo-project.org/book/Virtual-Machine/Building/BuildVMOnLinux http://pharo-project.org http://www.squeakvm.org/unix/