About CPAN Testers

Who, What, Why?

CPAN Testers is a volunteer effort to test distributions as they are uploaded to CPAN, the Perl code repository. There are currently over 100 testers, who are able to test across several different versions of Perl and on many different platforms.

There are two aims behind the CPAN Testers projects, firstly to give feedback to authors, and secondly to give users the opportunity to check whether a particular distribution will install and run on their system.

Authors often are limited to the number of Perl/platform combinations, so CPAN Testers provide a unique opportunity to get feedback on issues which they might not receive from users trying to use their distribution.

Users are also able to benefit from CPAN Testers, as the reports can highlight when a distribution might be problematic. Together with the other resources, such as the PASS Matrix, CPAN Dependencies and the CPAN Testers Matrix, users can make an informed choice as to which distributions might be best for them.


The CPAN testers was conceived back in May 1998 by Graham Barr and Chris Nandor as a way to provide multi-platform testing for modules. As of February 2012 there are over 20 million tester reports, with more than 100 testers giving valuable feedback for users and authors alike every month.

For several years testers created test reports by hand, until CPANPLUS included a simple test smoker script. This script was dropped when CPANPLUS-0.50 was redesigned, such that the new API was no longer compatible. Robert Rothenberg and Barbie wrote CPAN-YACSmoke, which lasted for several years. In the meantime those using CPAN.pm as their installer felt there should be a counterpart for them. As such David Golden wrote CPAN-Reporter. Due to lack of time to work on the core software, CPAN-YACSmoke started to stagnate, to the point Chris Williams wrote CPANPLUS-YACSmoke as a replacement.

The original eco-system was driven by an SMTP/NNTP infrastructure, which with the increased interest in the project, began to creak under the weight of the reports. In 2008 work on a redisgn began, and in 2010 CT2.0 was launched using the Metabase, a HTTP based system based, designed and developed by Ricardo Signes and David Golden.

The New Team

The people promoting CPAN Testers has changed over the years, as interest in the project fluctuates. However, right now we have a very dedicated team working behind the scenes to ensure that we are continually refining and improving the process of testing and reporting, and providing the authors with the right feedback to help improve their code.

Specific mentions should go to the following people, who although act as primary contacts for specific parts of the toolchain mentioned, all have helped to maintain CPAN Testers eco-system.

  • Dave Golden - CPAN-Reporter / Metabase
  • Chris 'BinGOs' Williams - CPANPLUS-Reporter / CPANPLUS
  • Andreas König - CPAN.pm
  • Jos Boumans - CPANPLUS
  • Ricardo Signes - Metabase
  • David Cantrell - CPAN Dependencies
  • Slaven Rezić - CPAN Testers Matrix
  • Barbie - DNS, Servers, Databases & Websites


If you have any issues with any part of the process, please use the resouces we have available to help improve the feedback and use of CPAN Testers to you. Specifically if you are an author or a tester, please see the CPAN Testers Wiki, to see if there is anything appropriate there, or join the 'CPAN Testers Discuss' mailing list and ask your question there. There are a number of testers and developers on the mailing list who are on hand to help out wherever possible.