NAME

    App::cpm - a fast CPAN module installer

SYNOPSIS

      > cpm install Module

DESCRIPTION

    cpm is a fast CPAN module installer, which uses Menlo in parallel.

    Moreover cpm keeps the each builds of distributions in your home
    directory, and reuses them later. That is, if prebuilts are available,
    cpm never builds distributions again, just copies the prebuilts into an
    appropriate directory. This is (of course!) inspired by Carmel.

    For tutorial, check out App::cpm::Tutorial.

MOTIVATION

    Why do we need a new CPAN client?

    I used cpanm a lot, and it's totally awesome.

    But if your Perl project has hundreds of CPAN module dependencies, then
    it takes quite a lot of time to install them.

    So my motivation is simple: I want to install CPAN modules as fast as
    possible.

 HOW FAST?

    Just an example:

      > time cpanm -nq -Lextlib Plack
      real 0m47.705s
    
      > time cpm install Plack
      real 0m16.629s

    This shows cpm is 3x faster than cpanm.

CAVEATS

    eserte <https://github.com/skaji/cpm/issues/71> reported that the
    parallel feature of cpm yielded a new type of failure for CPAN module
    installation. That is, if ModuleA implicitly requires ModuleB in
    configure/build phase, and ModuleB is about to be installed, then it
    may happen that the installation of ModuleA fails.

    I can say that it hardly happens especially if you use a new Perl.
    Moreover, for a workaround, cpm automatically retries the installation
    if it fails.

    I hope that if almost all CPAN modules are distributed with static
    install enabled
    <http://blogs.perl.org/users/shoichi_kaji1/2017/03/make-your-cpan-module-static-installable.html>,
    then cpm will parallelize the installation for these CPAN modules
    safely and we can eliminate this new type of failure completely.

ROADMAP

    If you all find cpm useful, then cpm should be merged into cpanm 2.0.
    How exciting!

    To merge cpm into cpanm, there are several TODOs:

      * (DONE) Win32? - support platforms that do not have fork(2) system
      call

      * (DONE) Logging? - the parallel feature makes log really messy

    Your feedback is highly appreciated.

COPYRIGHT AND LICENSE

    Copyright 2015 Shoichi Kaji <skaji@cpan.org>

    This library is free software; you can redistribute it and/or modify it
    under the same terms as Perl itself.

COMMUNITY

    https://github.com/skaji/cpm

      Code repository and issue tracker

    https://gitter.im/skaji/cpm

      Chat room. I would like to hear your thoughts about CPAN clients (not
      necessary about cpm)

SEE ALSO

    Perl Advent Calendar 2015
    <http://www.perladvent.org/2015/2015-12-02.html>

    App::cpanminus

    Menlo

    Carton

    Carmel

