Xonsh allows you to have run control files to customize your shell behavior. These are called ``xonshrc`` files.
The system-wide ``xonshrc`` file controls options that are applied to all users of Xonsh on a given system. You can create this file in ``/etc/xonshrc`` for Linux and OSX and in ``%ALLUSERSPROFILE%\xonsh\xonshrc`` on Windows.
Xonsh also allows you to have a run control file in your home directory called ``~/.xonshrc``. The options set in the local ``xonshrc`` only apply to the current user and will override any conflicting settings set in the system-wide control file.
These files are written in the xonsh language, of course. They are executed exactly once