Selective settings

We can add the following two lines to /etc/apt/sources.list:

deb http://mirrordirector.raspbian.org/raspbian/ jessie main contrib non-free rpi
deb http://archive.raspbian.org/raspbian jessie main contrib non-free rpi

The next step is to tell aptitude to use the wheezy repository for normal updates and that you would like to use Jessie from time to time. These settings should be typed into the file found at /etc/apt/preferences. Create this file if it does not exist:

Package: * 
Pin: release n=wheezy 
Pin-Priority: 900 

Package: * 
Pin: release n=jessie 
Pin-Priority: 300 

Package: * 
Pin: release o=Raspbian 
Pin-Priority: -10 

After adding these settings and saving the files, run sudo apt-get update.

We will be using apt-get with an extra switch to use the new packages. You should only use this switch when it is advised. Upgrading core packages could result in unstable behavior. The syntax we will be using is as follows, where <package> will be replaced with the game...