This is Math::BigInt::Pari, a plugin module for Math::BigInt that replaces Math::BigInt's core math routines with Math::Pari routines. This package contains a replacement (drop-in) module for Math::BigInt's core, Math::BigInt::Calc.pm. It needs the new versions of Math::BigInt and Math::BigFloat as they are from Perl 5.7.x onwards. How to install: perl Makefile.PL make make test make install To use it, install Math::Pari and then replace: use Math::BigInt; with this: use Math::BigInt lib => 'Pari'; If Math::Pari is not installed, this will safely fall back to Calc, the default library of Math::BigInt. Please read the documentation under PERFORMANCE in Math::BigInt on when to use this module and when not. Tels (http://bloodgate.com) & Benjamin Trott (ben at rhumba.pair.com)