Perl modules that involve XS (a C-like glue language for building Perl modules that bind to existing C code) depend on the major version (5.x) against which they were built. This has the side effect that when a major Perl upgrade happens in Arch Linux, almost all XS modules that were not built against that same version (mostly likely those built from the AUR) will break. I suggest that the depends line in PKGBUILD-perl.proto change from this:

depends=('perl>=5.10.0')

to something like this:

# for pure Perl modules
arch=('any')
depends=('perl>=5.8.9') # or whatever version the module requires, consult META.yml

# for non-pure Perl modules
arch=('i686' 'x86_64')
depends=('perl>=5.20.0' 'perl<5.21.0')

This allows modules to work with minor version changes, while requiring a rebuild when a new major version of Perl comes out. I'm hoping this PKGBUILD template change would encourage users who submit PKGBUILDs to the AUR to have these stricter checks in place, resulting in fewer unpleasant surprises when other users upgrade their system perl and they use modules from outside of the official repositories.