# Runtime Environments

This page contains notes about using various runtime environments inside Isolate 
sandboxes.

## Python

Due to a [Python bug](http://bugs.python.org/issue10496), the interpreter 
requires the `$HOME` variable to be set to something. Otherwise, it tries to 
look up the UID used by Isolate in `/etc/passwd` and fails. Setting `HOME=/box` 
seems to work.

We use a wrapper script that translates exceptions to error codes. This script can be found in the utils repository.

## Java

By default, we use a script that looks for a class with a `main` method and executes it for running Java programs. This script is located in the utils repository.