Ubuntu Wiki

Software in the main repository can only include build depends, depends and recommends on other software located in the main repository.
If it requires a some software located elsewhere, a MIR (MainInclusionRequest) must be filed, or the other software must be modified to not require that software. You can use Suggests to suggest a package located in another repo (like universe) - as Suggests does not install automatically.

Currently LP has a problem with BZR stacked branches. The following steps can fix it.

python
import bzrlib.branch
b = bzrlib.branch.Branch.open('bzr+ssh://bazaar.launchpad.net/~username/treename')
b.set_stacked_on_url('/~teamname/originaltreename')

To check for a specifc Depend

checkrdepends -b libcgi-pm-perl intrepid

When building for PPA - use debuild -S -sa

In this example the "-" means ignore error. -$(MAKE) distclean (its generally better to trap specific error)
diff -Nurp when making patches