release_managers_guide - Releasing a new version of perl 5.x

Note that things change at each release, so there may be new things not covered here, or tools may need updating.


If you are preparing to do a release, you can run the Porting/make-rmg-checklist script to generate a new version of this document that starts with a checklist for your release.

This script is run as:

 perl Porting/make-rmg-checklist \
     --version [5.X.Y-RC#] > /tmp/rmg.pod

You can also pass the --html flag to generate an HTML document instead of POD.

 perl Porting/make-rmg-checklist --html \
     --version [5.X.Y-RC#] > /tmp/rmg.html


This document describes the series of tasks required - some automatic, some manual - to produce a perl release of some description, be that a release candidate, or final, numbered release of maint or blead.

New releases of perl are made each month on the 20th by a release engineer appointed by the Steering Council. The release engineer roster and schedule can be found in Porting/release_schedule.pod.

This document both helps as a check-list for the release engineer and is a base for ideas on how the various tasks could be automated or distributed.

The checklist of a typical release cycle is as follows:

 (5.10.1 is released, and post-release actions have been done)

 ...time passes...

 a few weeks before the release, a number of steps are performed,
     including bumping the version to 5.10.2

 ...a few weeks pass...

 perl-5.10.2-RC1 is released

 perl-5.10.2 is released

 post-release actions are performed, including creating new

 ... the cycle continues ...


Some of the tasks described below apply to all four types of release of Perl. (blead, RC, final release of maint, final release of blead). Some of these tasks apply only to a subset of these release types. If a step does not apply to a given type of release, you will see a notation to that effect at the beginning of the step.

This guide assumes you are working on the Perl master repository (i.e. and not on your own fork of the perl5 repository. While it is possible to prepare a release on your own fork this guide is not written with that in mind and as a result several key steps are missing. If you do use your own fork then extra care needs to be taken when setting/pushing the tag and doing the merge (do not use a PR).

Release types

Release Candidate (RC)

A release candidate is an attempt to produce a tarball that is as close as possible to the final release. Indeed, unless critical faults are found during the RC testing, the final release will be identical to the RC barring a few minor fixups (updating the release date in perlhist.pod, removing the RC status from patchlevel.h, etc). If faults are found, then the fixes should be put into a new release candidate, never directly into a final release.

Stable/Maint release (MAINT).

A release with an even version number, and subversion number > 0, such as 5.14.1 or 5.14.2.

At this point you should have a working release candidate with few or no changes since.

It's essentially the same procedure as for making a release candidate, but with a whole bunch of extra post-release steps.

Note that for a maint release there are two versions of this guide to consider: the one in the maint branch, and the one in blead. Which one to use is a fine judgement. The blead one will be most up-to-date, while it might describe some steps or new tools that aren't applicable to older maint branches. It is probably best to review both versions of this document, but to most closely follow the steps in the maint version.

A blead point release (BLEAD-POINT)

A release with an odd version number, such as 5.15.0 or 5.15.1.

This isn't for production, so it has less stability requirements than for other release types, and isn't preceded by RC releases. Other than that, it is similar to a MAINT release.

Blead final release (BLEAD-FINAL)

A release with an even version number, and subversion number == 0, such as 5.14.0. That is to say, it's the big new release once per year.

It's essentially the same procedure as for making a release candidate, but with a whole bunch of extra post-release steps, even more than for MAINT.


Before you can make an official release of perl, there are a few hoops you need to jump through:

PAUSE account with pumpkin status

Make sure you have a PAUSE account suitable for uploading a perl release. If you don't have a PAUSE account, then request one:

Check that your account is allowed to upload perl distros: go to and check that your PAUSE ID is listed there. If not, ask Andreas König to add your ID to the list of people allowed to upload something called perl. You can find Andreas' email address at:

GitHub access

You will need a working git installation, checkout of the perl git repository and perl commit bit. For information about working with perl and git, see perlgit.

If you are not yet a perl committer, you won't be able to make a release. You will need to have a GitHub account (if you don't have one) and contact the Steering Council with your username to get membership in the Perl-Releasers team.

web-based file share

You will need to be able to share tarballs with #p5p members for pre-release testing, and you may wish to upload to PAUSE via URL. Make sure you have a way of sharing files, such as a web server or file-sharing service.

If you use Dropbox, you can append "raw=1" as a parameter to their usual sharing link to allow direct download (albeit with redirects).

Quotation for release announcement epigraph

You will need a quotation to use as an epigraph to your release announcement. It will live forever (along with Perl), so make it a good one.

Install the previous version of perl

During the testing phase of the release you have created, you will be asked to compare the installed files with a previous install. Save yourself some time on release day, and have a (clean) install of the previous version ready.

Email account subscribed to perl5-porters

In order for your release announcement email to be delivered to the perl5-porters distribution list, the email address that you intend to send from must be subscribed to the list.

Instructions for subscribing can be found here: List: perl5-porters

Building a release - advance actions

The work of building a release candidate for an even numbered release (BLEAD-FINAL) of perl generally starts several weeks before the first release candidate. Some of the following steps should be done regularly, but all must be done in the run up to a release.

dual-life CPAN module synchronisation

To see which core distro versions differ from the current CPAN versions:

 $ ./perl -Ilib Porting/core-cpan-diff -x -a

However, this only checks whether the version recorded in Porting/ differs from the latest on CPAN. It doesn't tell you if the code itself has diverged from CPAN.

You can also run an actual diff of the contents of the modules, comparing core to CPAN, to ensure that there were no erroneous/extraneous changes that need to be dealt with. You do this by not passing the -x option:

 $ ./perl -Ilib Porting/core-cpan-diff -a -o ~/corediffs

Passing -u cpan will probably be helpful, since it limits the search to distributions with 'cpan' upstream source. (It's OK for blead upstream to differ from CPAN because those dual-life releases usually come after perl is released.)

See also the -d and -v options for more detail (and the -u option as mentioned above). You'll probably want to use the -c cachedir option to avoid repeated CPAN downloads and may want to use -m file:///mirror/path if you made a local CPAN mirror. Note that a minicpan mirror won't actually work, but can provide a good first pass to quickly get a list of modules which definitely haven't changed, to avoid having to download absolutely everything.

For a BLEAD-POINT or BLEAD-FINAL release with 'cpan' upstream, if a CPAN release appears to be ahead of blead, then consider updating it (or asking the relevant porter to do so). (However, if this is a BLEAD-FINAL release or one of the last BLEAD-POINT releases before it and hence blead is in some kind of "code freeze" state (e.g. the sequence might be "contentious changes freeze", then "user-visible changes freeze" and finally "full code freeze") then any CPAN module updates must be subject to the same restrictions, so it may not be possible to update all modules until after the BLEAD-FINAL release.) If blead contains edits to a 'cpan' upstream module, this is naughty but sometimes unavoidable to keep blead tests passing. Make sure the affected file has a CUSTOMIZED entry in Porting/

If you are making a MAINT release, run core-cpan-diff on both blead and maint, then diff the two outputs. Compare this with what you expect, and if necessary, fix things up. For example, you might think that both blead and maint are synchronised with a particular CPAN module, but one might have some extra changes.

In any case, any cpan-first distribution that is listed as having files "Customized for blead" in the output of cpan-core-diff should have requests submitted to the maintainer(s) to make a cpan release to catch up with blead.

Additionally, all files listed as "modified" but not "customized for blead" should have entries added under the CUSTOMIZED key in Porting/, as well as checksums updated via:

 cd t; ../perl -I../lib porting/customized.t --regen

Sync CPAN modules with the corresponding cpan/ distro

In most cases, once a new version of a distribution shipped with core has been uploaded to CPAN, the core version thereof can be synchronized automatically with the program Porting/sync-with-cpan. (But see the comments at the beginning of that program. In particular, it has not yet been exercised on Windows as much as it has on Unix-like platforms.)

If, however, Porting/sync-with-cpan does not provide good results, follow the steps below.

  • Fetch the most recent version from CPAN.

  • Unpack the retrieved tarball. Rename the old directory; rename the new directory to the original name.

  • Restore any .gitignore file. This can be done by issuing git checkout .gitignore in the cpan/Distro directory.

  • Remove files we do not need. That is, remove any files that match the entries in @IGNORABLE in Porting/, and anything that matches the EXCLUDED section of the distro's entry in the %Modules hash.

  • Restore any files mentioned in the CUSTOMIZED section, using git checkout. Make any new customizations if necessary. Also, restore any files that are mentioned in @IGNORE, but were checked into the repository anyway.

  • For any new files in the distro, determine whether they are needed. If not, delete them, and list them in either EXCLUDED or @IGNORABLE. Otherwise, add them to MANIFEST, and run git add to add the files to the repository.

  • For any files that are gone, remove them from MANIFEST, and use git rm to tell git the files will be gone.

  • If the MANIFEST file was changed in any of the previous steps, run perl Porting/manisort --output MANIFEST.sort; mv MANIFEST.sort MANIFEST.

  • For any files that have an execute bit set, either remove the execute bit, or edit Porting/exec-bit.txt

  • Run make (or nmake on Windows), see if perl compiles.

  • Run the tests for the package.

  • Run the tests in t/porting (make test_porting).

  • Update the DISTRIBUTION entry in Porting/

  • Run a full configure/build/test cycle.

  • If everything is ok, commit the changes.

For entries with a non-simple FILES section, or with a MAP, you may have to take more steps than listed above.

Ensure dual-life CPAN module stability

This comes down to:

   for each module that fails its regression tests on $current
    did it fail identically on $previous?
    if yes, "SEP" (Somebody Else's Problem, but try to make sure a
      bug ticket is filed)
    else work out why it failed (a bisect is useful for this)

   attempt to group failure causes

   for each failure cause
    is that a regression?
    if yes, figure out how to fix it
        (more code? revert the code that broke it)
        (presumably) it's relying on something un-or-under-documented
        should the existing behaviour stay?
            yes - goto "regression"
            no - note it in perldelta as a significant bugfix
            (also, try to inform the module's author)

monitor smoke tests for failures

Similarly, monitor the smoking of core tests, and try to fix. See, and for a summary. See also which has the raw reports.

Similarly, monitor the smoking of perl for compiler warnings, and try to fix.

Additionally both Travis CI and GitHub Actions smokers run automatically.

monitor CPAN testers for failures

For any release except a BLEAD-POINT: Examine the relevant analysis report(s) at to see how the impending release is performing compared to previous releases with regard to building and testing CPAN modules.

That page accepts a query parameter, pair that takes a pair of colon-delimited versions to use for comparison. For example:

update perldelta

Get perldelta in a mostly finished state.

Read Porting/how_to_write_a_perldelta.pod, and try to make sure that every section it lists is, if necessary, populated and complete. Copy edit the whole document.

You won't be able to automatically fill in the "Updated Modules" section until after Module::CoreList is updated (as described below in "update Module::CoreList").

Bump the version number

Do not do this yet for a BLEAD-POINT release! You will do this at the end of the release process (after building the final tarball, tagging etc).

Increase the version number (e.g. from 5.12.0 to 5.12.1).

For a release candidate for a stable perl, this should happen a week or two before the first release candidate to allow sufficient time for testing and smoking with the target version built into the perl executable. For subsequent release candidates and the final release, it is not necessary to bump the version further.

There is a tool to semi-automate this process:

 $ ./perl -Ilib Porting/bump-perl-version -i 5.10.0 5.10.1

Remember that this tool is largely just grepping for '5.10.0' or whatever, so it will generate false positives. Be careful not change text like "this was fixed in 5.10.0"!

Use git status and git diff to select changes you want to keep.

Be particularly careful with INSTALL, which contains a mixture of 5.10.0-type strings, some of which need bumping on every release, and some of which need to be left unchanged. See below in "update INSTALL" for more details.

For the first RC release leading up to a BLEAD-FINAL release, update the description of which releases are now "officially" supported in pod/perlpolicy.pod.

When doing a BLEAD-POINT or BLEAD-FINAL release, also make sure the PERL_API_* constants in patchlevel.h are in sync with the version you're releasing, unless you're absolutely sure the release you're about to make is 100% binary compatible to an earlier release. Note: for BLEAD-POINT releases the bump should have already occurred at the end of the previous release and this is something you would have to do at the very end. When releasing a MAINT perl version, the PERL_API_* constants MUST NOT be changed as we aim to guarantee binary compatibility in maint branches.

After editing, regenerate uconfig.h (this must be run on a system with a /bin/sh available):

 $ perl regen/

This might not cause any new changes.

You may also need to regen opcodes:

 $ ./perl -Ilib regen/

Test your changes:

 $ git clean -xdf   # careful if you don't have local files to keep!
 $ ./Configure -des -Dusedevel
 $ make
 $ make test

Do note that at this stage, porting tests will fail. They will continue to fail until you've updated Module::CoreList, as described below.

Commit your changes:

 $ git status
 $ git diff
 B<review the delta carefully>

 $ git commit -a -m 'Bump the perl version in various places for 5.X.Y'

At this point you may want to compare the commit with a previous bump to see if they look similar. See commit f7cf42bb69 for an example of a previous version bump.

When the version number is bumped, you should also update Module::CoreList (as described below in "update Module::CoreList") to reflect the new version number.

update INSTALL

Review and update INSTALL to account for the change in version number. INSTALL for a BLEAD-POINT release should already contain the expected version. The lines in INSTALL about "is not binary compatible with" may require a correct choice of earlier version to declare incompatibility with. These are in the "Changes and Incompatibilities" and "Coexistence with earlier versions of perl 5" sections.

Be particularly careful with the section "Upgrading from 5.X.Y or earlier". The "X.Y" needs to be changed to the most recent version that we are not binary compatible with.

For MAINT and BLEAD-FINAL releases, this needs to refer to the last release in the previous development cycle (so for example, for a 5.14.x release, this would be 5.13.11).

For BLEAD-POINT releases, it needs to refer to the previous BLEAD-POINT release (so for 5.15.3 this would be 5.15.2). If the last release manager followed instructions, this should have already been done after the last blead release, so you may find nothing to do here.

update AUTHORS

The AUTHORS file can be updated by running Porting/

(The old method was Porting/ --update --from=5.X.Y and it's still used under the hood, but you should use the Porting/ update.)

In the old method, for MAINT and BLEAD-FINAL releases, v5.X.Y needs to refer to the last release in the previous development cycle (so for example, for a 5.14.x release, this would be 5.13.11).

In the old method, for BLEAD-POINT releases, it needs to refer to the previous BLEAD-POINT release (so for 5.15.3 this would be 5.15.2).

Note: It should not be harmful to use a wider range.

Note: If you have uncommitted changes this could cause some warnings, and you might like to use the additional argument --to=upstream/blead to use the last known git commit by GitHub.

Review the changes to the AUTHORS file, be sure you are not adding duplicate entries or removing any entries, then commit your changes.

 $ git commit -a AUTHORS -m 'Update AUTHORS list for 5.X.Y'

Check that the copyright years are up to date by running:

 $ pushd t; ../perl -I../lib porting/copyright.t --now

Remedy any test failures by editing README or perl.c accordingly (search for the "Copyright"). If updating perl.c, check if the file's own copyright date in the C comment at the top needs updating, as well as the one printed by -v.

Check more build configurations

Try running the full test suite against multiple Perl configurations. Here are some sets of Configure flags you can try:

  • -Duseshrplib -Dusesitecustomize

  • -Duserelocatableinc

  • -Dusethreads

If you have multiple compilers on your machine, you might also consider compiling with -Dcc=$other_compiler.

You can also consider pushing the repo to GitHub where Travis CI is enabled which would smoke different flavors of Perl for you.

update perlport

perlport has a section currently named Supported Platforms that indicates which platforms are known to build in the current release. If necessary update the list and the indicated version number.

check a readonly build

Even before other prep work, follow the steps in "build the tarball" and test it locally. Because a perl source tarballs sets many files read-only, it could test differently than tests run from the repository. After you're sure permissions aren't a problem, delete the generated directory and tarballs.

Building a release - on the day

This section describes the actions required to make a release that are performed near to, or on the actual release day.

re-check earlier actions

Review all the actions in the previous section, "Building a release - advance actions" to ensure they are all done and up-to-date.

create a release branch

For BLEAD-POINT releases, making a release from a release branch avoids the need to freeze blead during the release. This is less important for BLEAD-FINAL, MAINT, and RC releases, since blead will already be frozen in those cases. Create the branch by running

 git checkout -b release-5.X.Y

build a clean perl

Make sure you have a gitwise-clean perl directory (no modified files, unpushed commits etc):

 $ git status
 $ git clean -dxf

then configure and build perl so that you have a Makefile and porting tools:

 $ ./Configure -Dusedevel -des && make

Check module versions

For each Perl release since the previous release of the current branch, check for modules that have identical version numbers but different contents by running:

 $ ./perl -Ilib Porting/ --tag=v5.X.Y

(This is done automatically by t/porting/cmp_version.t for the previous release of the current branch, but not for any releases from other branches.)

Any modules that fail will need a version bump, plus a nudge to the upstream maintainer for 'cpan' upstream modules.

update Module::CoreList

Bump Module::CoreList* $VERSIONs

If necessary, bump $VERSION (there's no need to do this for every RC; in RC1, bump the version to a new clean number that will appear in the final release, and leave as-is for the later RCs and final). It may also happen that Module::CoreList has been modified in blead, and hence has a new version number already. (But make sure it is not the same number as a CPAN release.)

$Module::CoreList::Utils::VERSION should always be equal to $Module::CoreList::VERSION. If necessary, bump those two versions to match before proceeding.

Once again, the files to modify are:

  • dist/Module-CoreList/lib/Module/

  • dist/Module-CoreList/lib/Module/CoreList/

Update Module::CoreList with module version data for the new release.

Note that if this is a MAINT release, you should run the following actions from the maint branch, but commit the changes in blead and subsequently cherry-pick any releases since the last maint release and then your recent commit. XXX need a better example

[ Note that the procedure for handling Module::CoreList in maint branches is a bit complex, and the RMG currently don't describe a full and workable approach. The main issue is keeping Module::CoreList and its version number synchronised across all maint branches, blead and CPAN, while having to bump its version number for every RC release. See this brief p5p thread:

 Message-ID: <>

If you can devise a workable system, feel free to try it out, and to update the RMG accordingly!

DAPM May 2013 ] uses to verify information about dual-lived modules on CPAN. It can use a full, local CPAN mirror and/or fall back on HTTP::Tiny to fetch package metadata remotely.

(If you'd prefer to have a full CPAN mirror, see

Change to your perl checkout, and if necessary,

 $ make

Then, If you have a local CPAN mirror, run:

 $ ./perl -Ilib Porting/ ~/my-cpan-mirror

Otherwise, run:

 $ ./perl -Ilib Porting/ cpan

This will chug for a while, possibly reporting various warnings about badly-indexed CPAN modules unrelated to the modules actually in core. Assuming all goes well, it will update dist/Module-CoreList/lib/Module/ and possibly dist/Module-CoreList/lib/Module/CoreList/

Check those files over carefully:

 $ git diff dist/Module-CoreList/lib/Module/
 $ git diff dist/Module-CoreList/lib/Module/CoreList/

Bump version in Module::CoreList Changes

Also edit Module::CoreList's new version number in its Changes file. This file is dist/Module-CoreList/Changes. (BLEAD-POINT releases should have had this done already as a post-release action from the last commit.)

Add Module::CoreList version bump to perldelta

Add a perldelta entry for the new Module::CoreList version. You only need to do this if you want to add notes about the changes included with this version of Module::CoreList. Otherwise, its version bump will be automatically filled in below in "finalize perldelta".

Update %Module::CoreList::released

For any release except an RC: Update this version's entry in the %released hash with today's date.

Commit Module::CoreList changes

Finally, commit the new version of Module::CoreList: (unless this is for MAINT; in which case commit it to blead first, then cherry-pick it back).

 $ git commit -m 'Update Module::CoreList for 5.X.Y' \
     dist/Module-CoreList/Changes \
     dist/Module-CoreList/lib/Module/ \

Rebuild and test

Build and test to get the changes into the currently built lib directory and to ensure all tests are passing.

finalize perldelta

Finalize the perldelta. In particular, fill in the Acknowledgements section, which can be generated with something like:

 $ perl Porting/ v5.LAST..HEAD

Fill in the "New/Updated Modules" sections now that Module::CoreList is updated:

 $ ./perl -Ilib Porting/ \
     --mode=update pod/perldelta.pod

For a MAINT release use something like this instead:

 $ ./perl -Ilib Porting/ 5.020001 5.020002 \
     --mode=update pod/perldelta.pod

Ideally, also fill in a summary of the major changes to each module for which an entry has been added by

Re-read the perldelta to try to find any embarrassing typos and thinkos; remove any TODO or XXX flags; update the "Known Problems" section with any serious issues for which fixes are not going to happen now; and run through pod and spell checkers, e.g.

 $ podchecker -warnings -warnings pod/perldelta.pod
 $ spell pod/perldelta.pod
 $ aspell list < pod/perldelta.pod | sort -u

Also, you may want to generate and view an HTML version of it to check formatting, e.g.

 $ ./perl -Ilib ext/Pod-Html/bin/pod2html pod/perldelta.pod > \

You should add pod links for GitHub issue references thusly:

 $ perl -p -i -e'BEGIN{undef $/}; s{(GH\s+#)(\d+)}{L<$1$2|$2>}mg' pod/perldelta.pod

If you make changes, be sure to commit them.

remove stale perldeltas

For the first RC release that is ONLY for a BLEAD-FINAL, the perldeltas from the BLEAD-POINT releases since the previous BLEAD-FINAL should have now been consolidated into the current perldelta, and hence are now just useless clutter. They can be removed using:

 $ git rm <file1> <file2> ...

For example, for RC0 of 5.16.0:

 $ cd pod
 $ git rm perldelta515*.pod

add recent perldeltas

For the first RC for a MAINT release, copy in any recent perldeltas from blead that have been added since the last release on this branch. This should include any recent maint releases on branches older than your one, but not newer. For example if you're producing a 5.14.x release, copy any perldeltas from recent 5.10.x, 5.12.x etc maint releases, but not from 5.16.x or higher. Remember to

 $ git add <file1> <file2> ...

update and commit perldelta files

If you have added or removed any perldelta files via the previous two steps, then edit pod/perl.pod to add/remove them from its table of contents, then run Porting/ to propagate your changes there into all the other files that mention them (including MANIFEST). You'll need to git add the files that it changes.

Then build a clean perl and do a full test

 $ git status
 $ git clean -dxf
 $ ./Configure -Dusedevel -des
 $ make
 $ make test

Once all tests pass, commit your changes.

final check of perldelta placeholders

Check for any 'XXX' leftover section in the perldelta. Either fill them or remove these sections appropriately.

 $ git grep XX pod/perldelta.pod

build a clean perl

If you skipped the previous step (adding/removing perldeltas), again, make sure you have a gitwise-clean perl directory (no modified files, unpushed commits etc):

 $ git status
 $ git clean -dxf

then configure and build perl so that you have a Makefile and porting tools:

 $ ./Configure -Dusedevel -des && make

synchronise from blead's perlhist.pod

For the first RC for a MAINT release, copy in the latest pod/perlhist.pod from blead; this will include details of newer releases in all branches. In theory, blead's version should be a strict superset of the one in this branch, but it's probably safest to examine the changes first, to ensure that there's nothing in this branch that was forgotten from blead. An easy way to do that is with git checkout -p, to selectively apply any changes from the blead version to your current branch:

 $ git fetch origin
 $ git checkout -p origin/blead pod/perlhist.pod
 $ git commit -m 'Sync perlhist from blead' pod/perlhist.pod

update perlhist.pod

Add an entry to pod/perlhist.pod with the release date, e.g.:

 David    5.10.1       2009-Aug-06

List yourself in the left-hand column, and if this is the first release that you've ever done, make sure that your name is listed in the section entitled THE KEEPERS OF THE PUMPKIN.

If you're making a BLEAD-FINAL release, also update the "SELECTED RELEASE SIZES" section with the output of Porting/

Be sure to commit your changes:

 $ git commit -m 'Add new release to perlhist' pod/perlhist.pod

update patchlevel.h

You MUST SKIP this step for a BLEAD-POINT release

Update patchlevel.h to add a -RC1-or-whatever string; or, if this is a final release, remove it. For example:

  static const char * const local_patches[] = {
 +        ,"RC1"

Be sure to commit your change:

 $ git commit -m 'Bump version to RCnnn' patchlevel.h

run makemeta to update META files

 $ ./perl -Ilib Porting/makemeta

Be sure to commit any changes (if applicable):

 $ git status   # any changes?
 $ git commit -m 'Update META files' META.*

build, test and check a fresh perl

Build perl, then make sure it passes its own test suite, and installs:

 $ git clean -xdf
 $ ./Configure -des -Dprefix=/tmp/perl-5.X.Y-pretest

 # or if it's an odd-numbered version:
 $ ./Configure -des -Dusedevel -Dprefix=/tmp/perl-5.X.Y-pretest

 $ make test install

Check that the output of /tmp/perl-5.X.Y-pretest/bin/perl -v and /tmp/perl-5.X.Y-pretest/bin/perl -V are as expected, especially as regards version numbers, patch and/or RC levels, and @INC paths. Note that as they have been built from a git working directory, they will still identify themselves using git tags and commits. (Note that for an odd-numbered version, perl will install itself as perl5.X.Y). perl -v will identify itself as:

 This is perl 5, version X, subversion Y (v5.X.Y (v5.XX.Z-NNN-gdeadbeef))

where 5.X.Z is the latest tag, NNN the number of commits since this tag, and deadbeef commit of that tag.

Then delete the temporary installation.

create the release tag

Create the annotated tag identifying this release (e.g.):

 $ git tag v5.11.0 -m 'First release of the v5.11 series!'

It is VERY important that from this point forward, you not push your git changes to the Perl master repository. If anything goes wrong before you publish your newly-created tag, you can delete and recreate it. Once you push your tag, we're stuck with it and you'll need to use a new version number for your release.

Verify that your tag is annotated:

 $ git show v5.X.Y

The output must look similar to the following:

 tag v5.X.Y
 Tagger: Jesse Vincent <>
 Date:   Fri Oct 2 16:29:56 2009 -0400

build the tarball

Before you run the following, you might want to install 7-Zip (the p7zip-full package under Debian or the p7zip port on MacPorts) or the AdvanceCOMP suite (e.g. the advancecomp package under Debian, or the advancecomp port on macports - 7-Zip on Windows is the same code as AdvanceCOMP, so Windows users get the smallest files first time). These compress about 5% smaller than gzip and bzip2. Over the lifetime of your distribution this will save a lot of people a small amount of download time and disk space, which adds up.

In order to produce the xz tarball, XZ Utils are required. The xz utility is included with most modern UNIX-type operating systems and is available for Cygwin. A Windows port is available from

IMPORTANT: if you are on OS X, you must export COPYFILE_DISABLE=1 to prevent OS X resource files from being included in your tarball. After creating the tarball following the instructions below, inspect it to ensure you don't have files like ._foobar.

Create a tarball. Use the -s option to specify a suitable suffix for the tarball and directory name:

 $ cd root/of/perl/tree

 $ perl Porting/makerel -x -s RC1           # for a release candidate
 $ perl Porting/makerel -x                  # for the release itself

This creates the directory ../perl-x.y.z-RC1 or similar, copies all the MANIFEST files into it, sets the correct permissions on them, then tars it up as ../perl-x.y.z-RC1.tar.gz. The -x also produces a tar.xz file.

If you're getting your tarball suffixed with -uncommitted and you're sure your changes were all committed, you can override the suffix with:

 $ perl Porting/makerel -x -s ''

XXX if we go for extra tags and branches stuff, then add the extra details here

Finally, clean up the temporary directory, e.g.

 $ rm -rf ../perl-x.y.z-RC1

test the tarball

Once you have a tarball it's time to test the tarball (not the repository).

Copy the tarball to a web server

Copy the tarballs (.gz and .xz) to a web server somewhere you have access to.

Download the tarball to another machine and unpack it

Download the tarball to some other machine. For a release candidate, you really want to test your tarball on two or more different platforms and architectures.

Ask #p5p to test the tarball on different platforms

Once you've verified the tarball can be downloaded and unpacked, ask the #p5p IRC channel on for volunteers to test the tarballs on whatever platforms they can.

If you're not confident in the tarball, you can defer this step until after your own tarball testing, below.

Check that Configure works

Check that basic configuration and tests work on each test machine:

 $ ./Configure -des && make all minitest test

 # Or for a development release:
 $ ./Configure -Dusedevel -des && make all minitest test

Run the test harness and install

Check that the test harness and install work on each test machine:

 $ make distclean
 $ ./Configure -des -Dprefix=/install/path && \
       make all test_harness install
 $ cd /install/path

(Remember -Dusedevel above, for a development release.)

Check perl -v and perl -V

Check that the output of perl -v and perl -V are as expected, especially as regards version numbers, patch and/or RC levels, and @INC paths.

Note that the results may be different without a .git/ directory, which is why you should test from the tarball.

Run the Installation Verification Procedure utility

 $ ./perl -Ilib ./utils/perlivp
 # Or, perhaps:
 $ ./perl5.X.Y ./utils/perlivp5.X.Y
 All tests successful.

Compare the installed paths to the last release

Compare the pathnames of all installed files with those of the previous release (i.e. against the last installed tarball on this branch which you have previously verified using this same procedure). In particular, look for files in the wrong place, or files no longer included which should be. For example, suppose the about-to-be-released version is 5.10.1 and the previous is 5.10.0:

 cd installdir-5.10.0/
 find . -type f | perl -pe's/5\.10\.0/5.10.1/g' | sort > /tmp/f1
 cd installdir-5.10.1/
 find . -type f | sort > /tmp/f2
 diff -u /tmp/f[12]

Disable local::lib if it's turned on

If you're using local::lib, you should reset your environment before performing these actions:


Bootstrap the CPAN client

Bootstrap the CPAN client on the clean install:

 $ bin/cpan

 # Or, perhaps:
 $ bin/cpan5.X.Y

Install the Inline module with CPAN and test it

Try installing a popular CPAN module that's reasonably complex and that has dependencies; for example:

 CPAN> install Inline::C
 CPAN> quit

Check that your perl can run this:

 $ bin/perl -Ilib -lwe "use Inline C => q[int f() { return 42;}]; print f"

Make sure that perlbug works

Test perlbug with the following:

 $ bin/perlbug
 Subject: test bug report
 Local perl administrator [yourself]:
 Editor [vi]:
 Category [core]:
 Severity [low]:
 (edit report)
 Action (Send/Display/Edit/Subject/Save to File): f
 Name of file to save message in [perlbug.rep]:

and carefully examine the output (in perlbug.rep]), especially the "Locally applied patches" section.

monitor smokes

XXX This is probably irrelevant if working on a release branch, though MAINT or RC might want to push a smoke branch and wait.

Wait for the smoke tests to catch up with the commit which this release is based on (or at least the last commit of any consequence).

Then check that the smoke tests pass (particularly on Win32). If not, go back and fix things.

Note that for BLEAD-POINT releases this may not be practical. It takes a long time for the smokers to catch up, especially the Win32 smokers. This is why we have a RC cycle for MAINT and BLEAD-FINAL releases, but for BLEAD-POINT releases sometimes the best you can do is to plead with people on IRC to test stuff on their platforms, fire away, and then hope for the best.

upload to PAUSE

Once smoking is okay, upload it to PAUSE. This is the point of no return. If anything goes wrong after this point, you will need to re-prepare a new release with a new minor version or RC number.

(Log in, then select 'Upload a file to CPAN')

If your workstation is not connected to a high-bandwidth, high-reliability connection to the Internet, you should probably use the "GET URL" feature (rather than "HTTP UPLOAD") to have PAUSE retrieve the new release from wherever you put it for testers to find it. This will eliminate anxious gnashing of teeth while you wait to see if your 15 megabyte HTTP upload successfully completes across your slow, twitchy cable modem.

Remember: if your upload is partially successful, you may need to contact a PAUSE administrator or even bump the version of perl.

Upload the .gz and .xz versions of the tarball.

Note: You can also use the command-line utility to upload your tarballs, if you have it configured:

 cpan-upload perl-5.X.Y.tar.gz
 cpan-upload perl-5.X.Y.tar.xz

Do not proceed any further until you are sure that your tarballs are on CPAN. Check your authors directory to confirm that your uploads have been successful.

You can also check

which may be faster.

wait for indexing

You MUST SKIP this step for RC and BLEAD-POINT

Wait until you receive notification emails from the PAUSE indexer confirming that your uploads have been received. IMPORTANT -- you will probably get an email that indexing has failed, due to module permissions. This is considered normal.

disarm patchlevel.h

You MUST SKIP this step for BLEAD-POINT release

Disarm the patchlevel.h change; for example,

  static const char * const local_patches[] = {
 -        ,"RC1"

Be sure to commit your change:

 $ git commit -m 'Disarm RCnnn bump' patchlevel.h

announce to p5p

Mail to announce your new release, with a quote you prepared earlier. Get the SHA256 digests from the PAUSE email responses.

Use the template at Porting/release_announcement_template.txt

Send a carbon copy to

If your email does not appear on the list, but does not obviously bounce either, check that the email you are sending from is subscribed to the list.

merge release branch back to blead

Merge the (local) release branch back into master now, and delete it.

 git checkout blead
 git pull
 git merge release-5.X.Y
 git push
 git branch -d release-5.X.Y

Note: The merge will create a merge commit if other changes have been pushed to blead while you've been working on your release branch. Do NOT rebase your branch to avoid the merge commit (as you might normally do when merging a small branch into blead) since doing so will invalidate the tag that you created earlier.

publish the release tag

Now that you've shipped the new perl release to PAUSE and pushed your changes to the Perl master repository, it's time to publish the tag you created earlier too (e.g.):

 $ git push origin tag v5.X.Y

update epigraphs.pod

Add your quote to Porting/epigraphs.pod and commit it. You can include the customary link to the release announcement even before your message reaches the web-visible archives by looking for the X-List-Archive header in your message after receiving it back via perl5-porters.

blog about your epigraph

If you have a blog, please consider writing an entry in your blog explaining why you chose that particular quote for your epigraph.

Submit a pull request to For a dev release, update the link in docs/dev/perl5/index.html. For a stable release, update docs/shared/tpl/stats.html.

Release schedule

You MUST SKIP this step for RC

Tick the entry for your release in Porting/release_schedule.pod.

Module::CoreList nagging

You MUST SKIP this step for RC

Remind the current maintainer of Module::CoreList to push a new release to CPAN.

new perldelta

You MUST SKIP this step for RC

Create a new perldelta.

  • Confirm that you have a clean checkout with no local changes.

  • Run: perl Porting/

  • Run the git add commands it outputs to add new and modified files.

  • Verify that the build still works, by running ./Configure and make test_porting. (On Win32 use the appropriate make utility).

  • If t/porting/podcheck.t spots errors in the new pod/perldelta.pod, run ./perl -MTestInit t/porting/podcheck.t | less for more detail. Skip to the end of its test output to see the options it offers you.

  • When make test_porting passes, commit the new perldelta.

     git commit -m'New perldelta for 5.X.Y'

At this point you may want to compare the commit with a previous bump to see if they look similar. See commit ba03bc34a4 for an example of a previous version bump.

bump version

You MUST SKIP this step for RC and MAINT

If this was a BLEAD-FINAL release (i.e. the first release of a new maint series, 5.x.0 where x is even), then bump the version in the blead branch in git, e.g. 5.12.0 to 5.13.0.

First, add a new feature bundle to regen/, initially by just copying the exiting entry, and bump the file's $VERSION (after the __END__ marker); e.g.

      "5.14" => [qw(switch say state unicode_strings)],
 +    "5.15" => [qw(switch say state unicode_strings)],

Run regen/ to propagate the changes to lib/

Then follow the section "Bump the version number" to bump the version in the remaining files and test and commit.

If this was a BLEAD-POINT release, then just follow the section "Bump the version number".

After bumping the version, follow the section "update INSTALL" to ensure all version number references are correct.

(Note: The version is NOT bumped immediately after a MAINT release in order to avoid confusion and wasted time arising from bug reports relating to "intermediate versions" such as 5.20.1-and-a-bit: If the report is caused by a bug that gets fixed in 5.20.2 and this intermediate version already calls itself 5.20.2 then much time can be wasted in figuring out why there is a failure from something that "should have been fixed". If the bump is late then there is a much smaller window of time for such confusing bug reports to arise. (The opposite problem -- trying to figure out why there *is* a bug in something calling itself 5.20.1 when in fact the bug was introduced later -- shouldn't arise for MAINT releases since they should, in theory, only contain bug fixes but never regressions.))

clean build and test

Run a clean build and test to make sure nothing obvious is broken. This is very important, as commands run after this point must be run using the perl executable built with the bumped version number.

 $ git clean -xdf
 $ ./Configure -des -Dusedevel
 $ make
 $ make test

In particular, Porting/perldelta_template.pod is intentionally exempted from podchecker tests, to avoid false positives about placeholder text. However, once it's copied to pod/perldelta.pod the contents can now cause test failures. Problems should be resolved by doing one of the following:

  1. Replace placeholder text with correct text.

  2. If the problem is from a broken placeholder link, you can add it to the array @perldelta_ignore_links in t/porting/podcheck.t. Lines containing such links should be marked with XXX so that they get cleaned up before the next release.

  3. Following the instructions output by t/porting/podcheck.t on how to update its exceptions database.

push commits

Finally, push any commits done above.

 $ git push origin ....

create maint branch


If this was a BLEAD-FINAL release (i.e. the first release of a new maint series, 5.x.0 where x is even), then create a new maint branch based on the commit tagged as the current release.

Assuming you're using git 1.7.x or newer:

 $ git checkout -b maint-5.X v5.X.0
 $ git push origin -u maint-5.X

make the maint branch available in the APC

Clone the new branch into /srv/gitcommon/branches on camel so the APC will receive its changes.

 $ git clone --branch maint-5.14 /gitroot/perl.git \
 ?  /srv/gitcommon/branches/perl-5.14.x
 $ chmod -R g=u /srv/gitcommon/branches/perl-5.14.x

And nag the sysadmins to make this directory available via rsync.

XXX Who are the sysadmins? Contact info?

copy perldelta.pod to blead

You MUST SKIP this step for RC, BLEAD-POINT

Copy the perldelta.pod for this release into blead; for example:

 $ cd ..../blead
 $ cp -i ../5.10.x/pod/perldelta.pod pod/perl5101delta.pod  #for example
 $ git add pod/perl5101delta.pod

Don't forget to set the NAME correctly in the new file (e.g. perl5101delta rather than perldelta).

Edit pod/perl.pod to add an entry for the file, e.g.:

 perl5101delta          Perl changes in version 5.10.1

Then rebuild various files:

 $ perl Porting/

Finally, commit and push:

 $ git commit -a -m 'Add perlXXXdelta'
 $ git push origin ....

copy perlhist.pod entries to blead

Make sure any recent pod/perlhist.pod entries are copied to perlhist.pod on blead. e.g.

 5.8.9         2008-Dec-14


You MUST RETIRE to your preferred PUB, CAFE or SEASIDE VILLA for some much-needed rest and relaxation.

Thanks for releasing perl!

Building a release - the day after

update Module::CoreList

After a BLEAD-POINT release only

After Module::CoreList has shipped to CPAN by the maintainer, update Module::CoreList in the source so that it reflects the new blead version number:

  • Update Porting/ to list the new DISTRIBUTION on CPAN, which should be identical to what is currently in blead.

  • Bump the $VERSION in dist/Module-CoreList/lib/Module/ and dist/Module-CoreList/lib/Module/CoreList/

  • If you have a local CPAN mirror, run:

     $ ./perl -Ilib Porting/ ~/my-cpan-mirror

    Otherwise, run:

     $ ./perl -Ilib Porting/ cpan

    This will update dist/Module-CoreList/lib/Module/ and dist/Module-CoreList/lib/Module/CoreList/ as it did before, but this time adding new sections for the next BLEAD-POINT release.

  • Add the new $Module::CoreList::VERSION to dist/Module-CoreList/Changes.

  • Remake perl to get your changed .pm files propagated into lib/ and then run at least the dist/Module-CoreList/t/*.t tests and the test_porting makefile target to check that they're ok.

     $ cd t; ./TEST ../dist/Module-CoreList/t/*.t
     $ make test_porting
  • Run

     $ ./perl -Ilib -MModule::CoreList \
     -le 'print Module::CoreList->find_version($]) ? "ok" : "not ok"'

    and check that it outputs "ok" to prove that Module::CoreList now knows about blead's current version.

  • Commit and push your changes.

     $ git add -u
     $ git commit -m "Prepare Module::Corelist for 5.X.Y"
     $ git push origin

check tarball availability

Check various website entries to make sure the that tarball has appeared and is properly indexed:

  • Check your author directory under to ensure that the tarballs are available on the website.

  • Check /src on CPAN (on a fast mirror) to ensure that links to the new tarballs have appeared: There should be links in /src/5.0 (which is accumulating all new versions), and (for BLEAD-FINAL and MAINT only) an appropriate mention in /src/README.html (which describes the latest versions in each stable branch, with links).

    The /src/5.0 links should appear automatically, some hours after upload. If they don't, or the /src description is inadequate, ask Ask <>.

  • Check to ensure that the /src updates have been correctly mirrored to the website. If they haven't, ask Ask <>.

  • Check to see if it has indexed the distribution. It should be visible at a URL like

update release manager's guide

Go over your notes from the release (you did take some, right?) and update Porting/release_managers_guide.pod with any fixes or information that will make life easier for the next release manager.

For a BLEAD-POINT .0 release

This is the time for the project to decide the fate and begin to implement the required changes for experimental/deprecated features and API elements for the next BLEAD-FINAL, a year away.

Fortunately your job is not to do this yourself, but merely to remind people that this needs to get done. Send email to p5p. All of perlexperiment, perldeprecation, mathoms.c, perlapi, and perlintern need to be considered.


Based on, plus a whole bunch of other sources, including private correspondence.