Catalyst is an open source web application framework written in Perl, that closely follows the model–view–controller (MVC) architecture, and supports a number of experimental web patterns. It is written using Moose, a modern object system for Perl. Its design is heavily inspired by frameworks such as Ruby on Rails, Maypole, and Spring. Catalyst is primarily distributed through the CPAN, which is the official distribution channel for Perl libraries and applications.