Back in November I wrote that Desura was looking to open-source their client (the Desura server will remain closed-up) and now two months later they've finally committed to doing so and published the code.
Desura hopes that open-sourcing the client will result in a community growing around it with new features, bug-fixes, and to differentiate this multi-platform game distribution platform from Valve's Steam. Up to this point Desura has been mostly popular with indie game developers. Desura launched on Linux in November with more than 65 games. The client itself is only being actively developed by one employee at the company.
The open-source version of Desura is being developed on GitHub under the name Desurium. This open-source version is just not for the Linux code but for the Windows version too.
To build the Desura client under Linux you need the usual assortment of Linux build utilities (and a dependency on GCC 4.5+) along with the development libraries for GTK2, GConf, D-Bus, CUPS2, asound, bz2, X11, SSL, and others.
Desurium is licensed under the GNU GPLv3.