Implement CLI application by editing main.pl.
You may add new files to keep your code clean, if it is allowed in your challenge.

In main.pl, there is a function called main, which receives command line arguments as-is.

sub main {
    # code to run ...
}

main(@ARGV);

You can use the standard print() method to output results to standard output.

print("text to output");

To install external libraries, write dependencies in cpanfile. Dependencies will be install by using Carton.

Following sample from cpanfile has been verified to installs dependencies as expected.

requires 'Plack', '1.0'; # 1.0 or newer
requires 'JSON', '>= 2.00, < 2.80';
 
recommends 'JSON::XS', '2.0';
conflicts 'JSON', '< 1.0';
 
on 'test' => sub {
      requires 'Test::More', '>= 0.96, < 2.0';
        recommends 'Test::TCP', '1.12';
};
 
on 'develop' => sub {
      recommends 'Devel::NYTProf';
};
 
feature 'sqlite', 'SQLite support' => sub {
      recommends 'DBD::SQLite';
};