The criticism
module is available on CPAN, and is used as a pragma.
Basically, use of the pragma in your code runs your code through Perl::Critic
before each execution, it's an alternative to using the perlcritic
command-line tool.
Here's an except from the documentation:
This pragma enforces coding standards and promotes best-practices by running your file through Perl::Critic before every execution. In a production system, this usually isn't feasible because it adds a lot of overhead at start-up. If you have a separate development environment, you can effectively bypass the criticism pragma by not installing Perl::Critic in the production environment. If Perl::Critic can't be loaded, then criticism just fails silently.