Arch
"Arch is a revision control system with features that are ideal for free software and open source projects characterized by widely distributed development, concurrent support of multiple releases, and substantial amounts of development on branches."
Read some more about arch in another prominent GTK+ app at the Rhythmbox arch page.
Getting the Code
Debian unstable users can apt-get install tla.
The stable version of LogJam is currently 4.4. The development version is 4.5.
To get LogJam 4.4:
tla register-archive http://logjam.danga.com/arch/2004 tla get logjam@danga.com--2004/logjam--dev--4.4
To get LogJam 4.5:
tla register-archive http://logjam.danga.com/arch/2005 tla get logjam@danga.com--2005/logjam--dev--4.5
Once you have the code, a simple tla update in the directory should keep you up to date.
Browsing
Start at the logjam ViewARCH page.