Hi! without knowing a lot of Koha-internals (still..), I'd strongly prefer to have all the code in a lib dir (as is standard in Perl apps / modules for ages). There are also a lot of tools available to make using code stored `lib` (but not "installed" in the system, i.e. only available in the checkout) easy. The simplest is of course 'lib': https://perldoc.perl.org/lib Or more complex like https://metacpan.org/pod/lib::projectroot (which I wrote some time ago to handle a Monorepo setup; it also includes a comparison of different modules in the SEE ALSO section) OTOH, CGI::Session::Serialize is a cpan module, so technically it should not be checked out into the app code `lib`, but installed as a dependency. There are even more ways to handle installing of dependencies and the finding them, but the currently most comfortable one is https://metacpan.org/pod/Carton. Or (if running everything via Carton is too much of a change), a combination of https://metacpan.org/pod/local::lib and a modern CPAN client (https://metacpan.org/pod/App::cpanminus or https://metacpan.org/pod/App::cpm. I did not want to spam the actuall ticket with this, as I'm not sure if any of this is in fact relevant to the bug, and/or matches the current plans for Koha. Greetings, domm -- #!/usr/bin/perl https://domm.plix.at for(ref bless{},just'another'perl'hacker){s-:+-$"-g&&print$_.$/}