I had this problem when installing modules locally also. I wrote a small 'helper' module that I include from the command line, or in my scripts, which customises @INC for me by reading in a config file that contains a list of all directories I want added.

The module looks for a file /etc/perl5lib.pm (or %windir%/perl5lib.pm) and reads in a array ref of directories from that file.

It then massages @INC to include all relevant directories under those paths using hints from Config.pm about sitelib/privlib/archlib/vendorlib etc. without them needing to be explicitly declared.

You can download the file from here - it is too hackish to upload to CPAN as a module.

The /etc/perl5lib.pm file is in Data::Dumper format - it looks like this:

$VAR1=[
    '/opt/project1',
    '/opt/project2',
    ..
];
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Then to include all the above directories *and* any relevant vendorlib/sitelib/archlib etc directories under them in which modules may have been installed, run

perl -I/path/to/perl5lib.pm -Mperl5lib script.pl
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Or include in your script:

#!/bin/perl
use lib '/path/to/perl5lib.pm',
use perl5lib
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I did not know about the perl Makefile.PL PREFIX=<path> LIB=<path> option mentioned above though - that looks like a better idea if the modules are not already installed.