If you are really interested in GNU Zebra development, you can access the latest code via the Zebra CVS repository. To access Zebra CVS repository, you have to setup your environment variable like the example given below:

CVSROOT=":pserver:anoncvs@anoncvs.zebra.org:/cvsroot"
export CVSROOT

Then execute the "cvs login" command. You will be asked for an anoncvs password. The password is anoncvs. You only need cvs login the first time.

cvs login
[Password](please input anoncvs)

After this, you can access Zebra CVS repository.

cvs checkout zebra

will extract Zebra code.