I suggest you make configuration module config.pm and to declare standart interface for it. Then you may to define all config parameters inside this module and export it. For example:

package config;
use strict;
use Exporter;
our (@ISA, @EXPORT, @EXPORT_OK);
@ISA = qw(Exporter);
@EXPORT = qw($param_1, $param_2, $param_3);

our $param_1 = 'foo';
our $param_2 = 'bar';
...
1;
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