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cpanm - get, unpack build and install modules from CPAN


  cpanm Test::More                                 # install Test::More
  cpanm MIYAGAWA/Plack-0.99_05.tar.gz              # full distribution path
  cpanm  # install from URL
  cpanm ~/dists/MyCompany-Enterprise-1.00.tar.gz   # install from a local file
  cpanm --interactive Task::Kensho                 # Configure interactively
  cpanm .                                          # install from local directory
  cpanm --installdeps .                            # install all the deps for the current directory
  cpanm -L extlib Plack                            # install Plack and all non-core deps into extlib
  cpanm --mirror DBI  # use the fast-syncing mirror
  cpanm --scandeps Moose                           # See what modules will be installed for Moose


-i, --install

Installs the modules. This is a default behavior and this is just a compatibility option to make it work like cpan or cpanp.


Upgrades itself. It's just an alias for:

  cpanm App::cpanminus

Displays the distribution information in AUTHOR/Dist-Name-ver.tar.gz format in the standard out.


Installs the dependencies of the target distribution but won't build itself. Handy if you want to try the application from a version controlled repository such as git.

  cpanm --installdeps .

Download and unpack the distribution and then open the directory with your shell. Handy to poke around the source code or do manual testing.

-h, --help

Displays the help message.

-V, --version

Displays the version number.


You can specify the default options in PERL_CPANM_OPT environment variable.

-f, --force

Force install modules even when testing failed.

-n, --notest

Skip the testing of modules. Use this only when you just want to save time for installing hundreds of distributions to the same perl and architecture you've already tested to make sure it builds fine.

Defaults to false, and you can say --no-notest to override when it is set in the default options in PERL_CPANM_OPT.


Run the tests only, and do not install the specified module or distributions. Handy if you want to verify the new (or even old) releases pass its unit tests without installing the module.

Note that if you specify this option with a module or distribution that has dependencies, these dependencies will be installed if you don't currently have them.

-S, --sudo

Switch to the root user with sudo when installing modules. Use this if you want to install modules to the system perl include path.

Defaults to false, and you can say --no-sudo to override when it is set in the default options in PERL_CPANM_OPT.

-v, --verbose

Makes the output verbose. It also enables the interactive configuration. (See --interactive)

-q, --quiet

Makes the output even more quiet than the default. It doesn't print anything to the STDERR.

-l, --local-lib

Sets the local::lib compatible path to install modules to. You don't need to set this if you already configure the shell environment variables using local::lib, but this can be used to override that as well.

-L, --local-lib-contained

Same with --local-lib but when examining the dependencies, it assumes no non-core modules are installed on the system. It's handy if you want to bundle application dependencies in one directory so you can distribute to other machines.

For instance,

  cpanm -L extlib Plack

would install Plack and all of its non-core dependencies into the directory extlib, which can be loaded from your application with:

  use local::lib '/path/to/extlib';

Specifies the base URL for the CPAN mirror to use, such as (you can omit the trailing slash). You can specify multiple mirror URLs by repeating the command line option.

Defaults to which is a geo location aware redirector.


Download the mirror's 02packages.details.txt.gz index file instead of querying the CPAN Meta DB.

Select this option if you are using a local mirror of CPAN, such as minicpan when you're offline, or your own CPAN index (a.k.a darkpan).

Tip: It might be useful if you name these mirror options with your shell aliases, like:

  alias minicpanm='cpanm --mirror ~/minicpan --mirror-only'
  alias darkpan='cpanm --mirror --mirror-only'

EXPERIMENTAL: Specifies the file path to 02packages.details.txt for module search index.


EXPERIMENTAL: Use API for module lookup instead of


Prompts when a test fails so that you can skip, force install, retry or look in the shell to see what's going wrong. It also prompts when one of the dependency failed if you want to proceed the installation.

Defaults to false, and you can say --no-prompt to override if it's set in the default options in PERL_CPANM_OPT.


cpanm, when given a module name in the command line (i.e. cpanm Plack), checks the locally installed version first and skips if it is already installed. This option makes it skip the check, so:

  cpanm --reinstall Plack

would reinstall Plack even if your locally installed version is latest, or even newer (which would happen if you install a developer release from version control repositories).

Defaults to false.


Makes the configuration (such as Makefile.PL and Build.PL) interactive, so you can answer questions in the distribution that requires custom configuration or Task:: distributions.

Defaults to false, and you can say --no-interactive to override when it's set in the default options in PERL_CPANM_OPT.


Scans the depencencies of given modules and output the tree in a text format. (See --format below for more options)

Because this command doesn't actually install any distributions, it will be useful that by typing:

  cpanm --scandeps Catalyst::Runtime

you can make sure what modules will be installed.

This command takes into account which modules you already have installed in your system. If you want to see what modules will be installed against a vanilla perl installation, you might want to combine it with -L option.


Determines what format to display the scanned dependency tree. Available options are tree, json, yaml and dists.


Displays the tree in a plain text format. This is the default value.

json, yaml

Outputs the tree in a JSON or YAML format. JSON and YAML modules need to be installed respectively. The output tree is represented as a recursive tuple of:

  [ distribution, dependencies ]

and the container is an array containing the root elements. Note that there may be multiple root nodes, since you can give multiple modules to the --scandeps command.


dists is a special output format, where it prints the distribution filename in the depth first order after the dependency resolution, like:


which means you can install these distributions in this order without extra dependencies. When combined with -L option, it will be useful to replay installations on other machines.


Specifies the optional directory path to copy downloaded tarballs in the CPAN mirror compatible directory structure i.e. authors/id/A/AU/AUTHORS/Foo-Bar-version.tar.gz


Uninstalls the shadow files of the distribution that you're installing. This eliminates the confusion if you're trying to install core (dual-life) modules from CPAN against perl 5.10 or older, or modules that used to be XS-based but switched to pure perl at some version.

If you run cpanm as root and use INSTALL_BASE or equivalent to specify custom installation path, you SHOULD disable this option so you won't accidentally uninstall dual-life modules from the core include path.

Defaults to true if your perl version is smaller than 5.12, and you can disable that with --no-uninst-shadows.

NOTE: Since version 1.3000 this flag is turned off by default for perl newer than 5.12, since with 5.12 @INC contains site_perl directory before the perl core library path, and uninstalling shadows is not necessary anymore and does more harm by deleting files from the core library path.

EXPERIMENTAL: Specifies whether to cascade search when you specify multiple mirrors and a mirror doesn't have a module or has a lower version of the module than requested. Defaults to false.


Specifies whether a module given in the command line is skipped if its latest version is already installed. Defaults to true.

NOTE: The PERL5LIB environment variable have to be correctly set for this to work with modules installed using local::lib.


EXPERIMENTAL: Specifies whether a module (and version) given in the command line is skipped if it's already installed.

If you run:

  cpanm --skip-satisfied CGI DBI~1.2

cpanm won't install them if you already have CGI (for whatever versions) or have DBI with version higher than 1.2. It is similar to --skip-installed but while --skip-installed checks if the latest version of CPAN is installed, --skip-satisfied checks if a requested version (or not, which means any version) is installed.

Defaults to false for bare module names, but if you specify versions with ~, it will always skip satisfied requirements.


Specifies the number of days in which cpanm's work directories expire. Defaults to 7, which means old work directories will be cleaned up in one week.

You can set the value to 0 to make cpan never cleanup those directories.


Generates man pages for executables (man1) and libraries (man3).

Defaults to false (no man pages generated) if -L|--local-lib-contained option is supplied. Otherwise, defaults to true, and you can disable it with --no-man-pages.


Uses LWP module to download stuff over HTTP. Defaults to true, and you can say --no-lwp to disable using LWP, when you want to upgrade LWP from CPAN on some broken perl systems.


Uses GNU Wget (if available) to download stuff. Defaults to true, and you can say --no-wget to disable using Wget (versions of Wget older than 1.9 don't support the --retry-connrefused option used by cpanm).


Uses cURL (if available) to download stuff. Defaults to true, and you can say --no-curl to disable using cURL.

Normally with --lwp, --wget and --curl options set to true (which is the default) cpanm tries LWP, Wget, cURL and HTTP::Tiny (in that order) and uses the first one available.




Copyright 2010 Tatsuhiko Miyagawa.


Tatsuhiko Miyagawa