could reasonably depend only on perl-base

byobu depends on perl, but only ships a single perl script using no modules. It could reasonably depend only on perl-base instead (or, equivalently, drop the dependency entirely since perl-base is Essential) to shrink its dependencies down substantially. As a concrete example, this would allow it to be installed on top of a debootstrapped Ubuntu base system without installing the full perl and perl-modules packages. byobu is one of the two packages in the Ubuntu server seed that require perl, the other being landscape-common.

To implement this, you can keep ${perl:Depends} in debian/control, but you'd do this in debian/rules:

  override_dh_perl:
          dh_perl -d

And also of course Build-Depends: debhelper (>= 7.0.50~) for override support.