An online programming assignment grading system.
CRJudge is a free and open source online judge for C, C++, Java and Python programming courses.
The web interface is written in PHP (CodeIgniter framework) and the main backend is written in BASH.
Python in CRJudge is not sandboxed yet. Just a simple (low) level of security is provided for python. If you want to use CRJudge for python, USE IT AT YOUR OWN RISK or provide sandboxing yourself.