Function::Fallback::CoreOrPP provides functions that use non-core XS modules (for best speed, reliability, feature, etc) but falls back to those that use core XS or pure-Perl modules when the non-core XS module is not available. This module helps when you want to bootstrap your Perl application with a portable, dependency-free Perl script. In a vanilla Perl installation (having only core modules), you can use App::FatPacker to include non-core pure-Perl dependencies to your script. WWW: https://metacpan.org/release/Function-Fallback-CoreOrPP