# Managing Packages

This chapter contains information related to creating, uploading, maintaining, and porting packages.

## New packages

If you want to create a new package for the Debian distribution, you should first check the Work-Needing and Prospective Packages (WNPP) list. Checking the WNPP list ensures that no one is already working on packaging that software, and that effort is not duplicated. Read the WNPP web pages for more information.

Assuming no one else is already working on your prospective package, you must then submit a bug report (submit-bug) against the pseudo-package `wnpp` describing your plan to create a new package, including, but not limiting yourself to, a description of the package, the license of the prospective package, and the current URL where it can be downloaded from.

You should set the subject of the bug to `ITP: `foo` -- `short description``, substituting the name of the new package for `foo`. The severity of the bug report must be set to `wishlist`. Please send a copy to &email-debian-devel; by using the X-Debbugs-CC header (don't use CC:, because that way the message's subject won't indicate the bug number). If you are packaging so many new packages (>10) that notifying the mailing list in separate messages is too disruptive, send a summary after filing the bugs to the debian-devel list instead. This will inform the other developers about upcoming packages and will allow a review of your description and package name.

Please include a `Closes: #`nnnnn`` entry in the changelog of the new package in order for the bug report to be automatically closed once the new package is installed in the archive (see upload-bugfix).

If you think your package needs some explanations for the administrators of the NEW package queue, include them in your changelog, send to &email-ftpmaster; a reply to the email you receive as a maintainer after your upload, or reply to the rejection email in case you are already re-uploading.

When closing security bugs include CVE numbers as well as the `Closes: #`nnnnn``. This is useful for the security team to track vulnerabilities. If an upload is made to fix the bug before the advisory ID is known, it is encouraged to modify the historical changelog entry with the next upload. Even in this case, please include all available pointers to background information in the original changelog entry.

There are a number of reasons why we ask maintainers to announce their intentions:

- It helps the (potentially new) maintainer to tap into the experience of people on the list, and lets them know if anyone else is working on it already.

- It lets other people thinking about working on the package know that there already is a volunteer, so efforts may be shared.

- It lets the rest of the maintainers know more about the package than the one line description and the usual changelog entry ``Initial release'' that gets posted to &email-debian-devel-changes;.

- It is helpful to the people who live off `unstable` (and form our first line of testers). We should encourage these people.

- The announcements give maintainers and other interested parties a better feel of what is going on, and what is new, in the project.

Please see for common rejection reasons for a new package.

## Recording changes in the package

Changes that you make to the package need to be recorded in the `debian/changelog`. These changes should provide a concise description of what was changed, why (if it's in doubt), and note if any bugs were closed. They also record when the package was completed. This file will be installed in `/usr/share/doc/`package`/changelog.Debian.gz`, or `/usr/share/doc/`package`/changelog.gz` for native packages.

The `debian/changelog` file conforms to a certain structure, with a number of different fields. One field of note, the `distribution`, is described in distribution. More information about the structure of this file can be found in the Debian Policy section titled `debian/changelog`.

Changelog entries can be used to automatically close Debian bugs when the package is installed into the archive. See upload-bugfix.

It is conventional that the changelog entry of a package that contains a new upstream version of the software looks like this:

      * New upstream release.

There are tools to help you create entries and finalize the `changelog` for release — see devscripts and dpkg-dev-el.

See also bpp-debian-changelog.

## Testing the package

Before you upload your package, you should do basic testing on it. At a minimum, you should try the following activities (you'll need to have an older version of the same Debian package around):

- Install the package and make sure the software works, or upgrade the package from an older version to your new version if a Debian package for it already exists.

- Run `lintian` over the package. You can run `lintian` as follows: `lintian -v `package-version`.changes`. This will check the source package as well as the binary package. If you don't understand the output that `lintian` generates, try adding the `-i` switch, which will cause `lintian` to output a very verbose description of the problem.

  Normally, a package should not be uploaded if it causes `lintian` to emit errors (they will start with `E`).

  For more information on `lintian`, see lintian.

- Optionally run `debdiff` (see debdiff) to analyze changes from an older version, if one exists.

- Downgrade the package to the previous version (if one exists) — this tests the `postrm` and `prerm` scripts.

- Remove the package, then reinstall it.

- Copy the source package in a different directory and try unpacking it and rebuilding it. This tests if the package relies on existing files outside of it, or if it relies on permissions being preserved on the files shipped inside the `.diff.gz` file.

## Layout of the source package

There are two types of Debian source packages:

- the so-called `native` packages, where there is no distinction between the original sources and the patches applied for Debian

- the (more common) packages where there's an original source tarball file accompanied by another file that contains the changes made by Debian

For the native packages, the source package includes a Debian source control file (`.dsc`) and the source tarball (`.tar.{gz,bz2,xz}`). A source package of a non-native package includes a Debian source control file, the original source tarball (`.orig.tar.{gz,bz2,xz}`) and the Debian changes (`.diff.gz` for the source format “1.0” or `.debian.tar.{gz,bz2,xz}` for the source format “3.0 (quilt)”).

With source format “1.0”, whether a package is native or not was determined by `dpkg-source` at build time. Nowadays it is recommended to be explicit about the desired source format by putting either “3.0 (quilt)” or “3.0 (native)” in `debian/source/format`. The rest of this section relates only to non-native packages.

The first time a version is uploaded which corresponds to a particular upstream version, the original source tar file should be uploaded and included in the `.changes` file. Subsequently, this very same tar file should be used to build the new diffs and `.dsc` files, and will not need to be re-uploaded.

By default, `dpkg-genchanges` and `dpkg-buildpackage` will include the original source tar file if and only if the current changelog entry has a different upstream version from the preceding entry. This behavior may be modified by using `-sa` to always include it or `-sd` to always leave it out.

If no original source is included in the upload, the original source tar-file used by `dpkg-source` when constructing the `.dsc` file and diff to be uploaded must be byte-for-byte identical with the one already in the archive.

Please notice that, in non-native packages, permissions on files that are not present in the `*.orig.tar.{gz,bz2,xz}` will not be preserved, as diff does not store file permissions in the patch. However when using source format “3.0 (quilt)”, permissions of files inside the `debian` directory are preserved since they are stored in a tar archive.

## Picking a distribution

Each upload needs to specify which distribution the package is intended for. The package build process extracts this information from the first line of the `debian/changelog` file and places it in the `Distribution` field of the `.changes` file.

There are several possible values for this field: `stable`, `unstable`, `testing-proposed-updates` and `experimental`. Normally, packages are uploaded into `unstable`.

Actually, there are other possible distributions: `codename``-security`, but read bug-security for more information on those.

It is not possible to upload a package into several distributions at the same time.

### Special case: uploads to the `stable` and `oldstable` distributions

Uploading to `stable` means that the package will transferred to the `proposed-updates-new` queue for review by the stable release managers, and if approved will be installed in `stable-proposed-updates` directory of the Debian archive. From there, it will be included in `stable` with the next point release.

To ensure that your upload will be accepted, you should discuss the changes with the stable release team before you upload. For that, file a bug against the `release.debian.org` pseudo-package using `reportbug`, including the patch you want to apply to the package version currently in `stable`. Always be verbose and detailed in your changelog entries for uploads to the `stable` distribution.

Extra care should be taken when uploading to `stable`. Basically, a package should only be uploaded to `stable` if one of the following happens:

- a truly critical functionality problem

- the package becomes uninstallable

- a released architecture lacks the package

In the past, uploads to `stable` were used to address security problems as well. However, this practice is deprecated, as uploads used for Debian security advisories are automatically copied to the appropriate `proposed-updates` archive when the advisory is released. See bug-security for detailed information on handling security problems. If the security teams deems the problem to be too benign to be fixed through a `DSA`, the stable release managers are usually willing to include your fix nonetheless in a regular upload to `stable`.

Changing anything else in the package that isn't important is discouraged, because even trivial fixes can cause bugs later on.

Packages uploaded to `stable` need to be compiled on systems running `stable`, so that their dependencies are limited to the libraries (and other packages) available in `stable`; for example, a package uploaded to `stable` that depends on a library package that only exists in `unstable` will be rejected. Making changes to dependencies of other packages (by messing with `Provides` or `shlibs` files), possibly making those other packages uninstallable, is strongly discouraged.

Uploads to the `oldstable` distributions are possible as long as it hasn't been archived. The same rules as for `stable` apply.

### Special case: uploads to `testing/testing-proposed-updates`

Please see the information in the testing section for details.

## Uploading a package

### Uploading to `ftp-master`

To upload a package, you should upload the files (including the signed changes and dsc-file) with anonymous ftp to `&ftp-upload-host;` in the directory &upload-queue;. To get the files processed there, they need to be signed with a key in the Debian Developers keyring or the Debian Maintainers keyring (see ).

Please note that you should transfer the changes file last. Otherwise, your upload may be rejected because the archive maintenance software will parse the changes file and see that not all files have been uploaded.

You may also find the Debian packages dupload or dput useful when uploading packages.These handy programs help automate the process of uploading packages into Debian.

For removing packages, please see and the Debian package dcut.

### Delayed uploads

It is sometimes useful to upload a package immediately, but to want this package to arrive in the archive only a few days later. For example, when preparing a Non-Maintainer Upload, you might want to give the maintainer a few days to react.

An upload to the delayed directory keeps the package in the deferred uploads queue. When the specified waiting time is over, the package is moved into the regular incoming directory for processing. This is done through automatic uploading to `&ftp-upload-host;` in upload-directory `DELAYED/`X`-day` (`X` between 0 and 15). 0-day is uploaded multiple times per day to `&ftp-upload-host;`.

With dput, you can use the `--delayed `DELAY`` parameter to put the package into one of the queues.

### Security uploads

Do NOT upload a package to the security upload queue (on `security-master.debian.org`) without prior authorization from the security team. If the package does not exactly meet the team's requirements, it will cause many problems and delays in dealing with the unwanted upload. For details, please see bug-security.

### Other upload queues

There is an alternative upload queue in Europe at . It operates in the same way as `&ftp-upload-host;`, but should be faster for European developers.

Packages can also be uploaded via ssh to `&ssh-upload-host;`; files should be put `/srv/upload.debian.org/UploadQueue`. This queue does not support delayed uploads.

### Notification that a new package has been installed

The Debian archive maintainers are responsible for handling package uploads. For the most part, uploads are automatically handled on a daily basis by the archive maintenance tools, `dak process-upload`. Specifically, updates to existing packages to the `unstable` distribution are handled automatically. In other cases, notably new packages, placing the uploaded package into the distribution is handled manually. When uploads are handled manually, the change to the archive may take some time to occur. Please be patient.

In any case, you will receive an email notification indicating that the package has been added to the archive, which also indicates which bugs will be closed by the upload. Please examine this notification carefully, checking if any bugs you meant to close didn't get triggered.

The installation notification also includes information on what section the package was inserted into. If there is a disparity, you will receive a separate email notifying you of that. Read on below.

Note that if you upload via queues, the queue daemon software will also send you a notification by email.

## Specifying the package section, subsection and priority

The `debian/control` file's `Section` and `Priority` fields do not actually specify where the file will be placed in the archive, nor its priority. In order to retain the overall integrity of the archive, it is the archive maintainers who have control over these fields. The values in the `debian/control` file are actually just hints.

The archive maintainers keep track of the canonical sections and priorities for packages in the `override file`. If there is a disparity between the `override file` and the package's fields as indicated in `debian/control`, then you will receive an email noting the divergence when the package is installed into the archive. You can either correct your `debian/control` file for your next upload, or else you may wish to make a change in the `override file`.

To alter the actual section that a package is put in, you need to first make sure that the `debian/control` file in your package is accurate. Next, submit a bug against `ftp.debian.org` requesting that the section or priority for your package be changed from the old section or priority to the new one. Use a Subject like `override: PACKAGE1:section/priority, [...], PACKAGEX:section/priority`, and include the justification for the change in the body of the bug report.

For more information about `override files`, see

dpkg-scanpackages

1 and .

Note that the `Section` field describes both the section as well as the subsection, which are described in archive-sections. If the section is main, it should be omitted. The list of allowable subsections can be found in .

## Handling bugs

Every developer has to be able to work with the Debian bug tracking system. This includes knowing how to file bug reports properly (see submit-bug), how to update them and reorder them, and how to process and close them.

The bug tracking system's features are described in the BTS documentation for developers. This includes closing bugs, sending followup messages, assigning severities and tags, marking bugs as forwarded, and other issues.

Operations such as reassigning bugs to other packages, merging separate bug reports about the same issue, or reopening bugs when they are prematurely closed, are handled using the so-called control mail server. All of the commands available on this server are described in the BTS control server documentation.

### Monitoring bugs

If you want to be a good maintainer, you should periodically check the Debian bug tracking system (BTS) for your packages. The BTS contains all the open bugs against your packages. You can check them by browsing this page: `http://&bugs-host;/`yourlogin`@debian.org`.

Maintainers interact with the BTS via email addresses at `&bugs-host;`. Documentation on available commands can be found at , or, if you have installed the `doc-debian` package, you can look at the local files &file-bts-docs;.

Some find it useful to get periodic reports on open bugs. You can add a cron job such as the following if you want to get a weekly email outlining all the open bugs against your packages:

    # ask for weekly reports of bugs in my packages
    &cron-bug-report;

Replace `address` with your official Debian maintainer address.

### Responding to bugs

When responding to bugs, make sure that any discussion you have about bugs is sent both to the original submitter of the bug, and to the bug itself (e.g., `123`@&bugs-host;). If you're writing a new mail and you don't remember the submitter email address, you can use the `123`-submitter@&bugs-host; email to contact the submitter and to record your mail within the bug log (that means you don't need to send a copy of the mail to `123`@&bugs-host;).

If you get a bug which mentions FTBFS, this means Fails to build from source. Porters frequently use this acronym.

Once you've dealt with a bug report (e.g. fixed it), mark it as `done` (close it) by sending an explanation message to `123`-done@&bugs-host;. If you're fixing a bug by changing and uploading the package, you can automate bug closing as described in upload-bugfix.

You should never close bugs via the bug server `close` command sent to &email-bts-control;. If you do so, the original submitter will not receive any information about why the bug was closed.

### Bug housekeeping

As a package maintainer, you will often find bugs in other packages or have bugs reported against your packages which are actually bugs in other packages. The bug tracking system's features are described in the BTS documentation for Debian developers. Operations such as reassigning, merging, and tagging bug reports are described in the BTS control server documentation. This section contains some guidelines for managing your own bugs, based on the collective Debian developer experience.

Filing bugs for problems that you find in other packages is one of the civic obligations of maintainership, see submit-bug for details. However, handling the bugs in your own packages is even more important.

Here's a list of steps that you may follow to handle a bug report:

1. Decide whether the report corresponds to a real bug or not. Sometimes users are just calling a program in the wrong way because they haven't read the documentation. If you diagnose this, just close the bug with enough information to let the user correct their problem (give pointers to the good documentation and so on). If the same report comes up again and again you may ask yourself if the documentation is good enough or if the program shouldn't detect its misuse in order to give an informative error message. This is an issue that may need to be brought up with the upstream author.

   If the bug submitter disagrees with your decision to close the bug, they may reopen it until you find an agreement on how to handle it. If you don't find any, you may want to tag the bug `wontfix` to let people know that the bug exists but that it won't be corrected. If this situation is unacceptable, you (or the submitter) may want to require a decision of the technical committee by reassigning the bug to `tech-ctte` (you may use the clone command of the BTS if you wish to keep it reported against your package). Before doing so, please read the recommended procedure.

2. If the bug is real but it's caused by another package, just reassign the bug to the right package. If you don't know which package it should be reassigned to, you should ask for help on IRC or on &email-debian-devel;. Please inform the maintainer(s) of the package you reassign the bug to, for example by Cc:ing the message that does the reassign to `packagename`@packages.debian.org and explaining your reasons in that mail. Please note that a simple reassignment is not e-mailed to the maintainers of the package being reassigned to, so they won't know about it until they look at a bug overview for their packages.

   If the bug affects the operation of your package, please consider cloning the bug and reassigning the clone to the package that really causes the behavior. Otherwise, the bug will not be shown in your package's bug list, possibly causing users to report the same bug over and over again. You should block "your" bug with the reassigned, cloned bug to document the relationship.

3. Sometimes you also have to adjust the severity of the bug so that it matches our definition of the severity. That's because people tend to inflate the severity of bugs to make sure their bugs are fixed quickly. Some bugs may even be dropped to wishlist severity when the requested change is just cosmetic.

4. If the bug is real but the same problem has already been reported by someone else, then the two relevant bug reports should be merged into one using the merge command of the BTS. In this way, when the bug is fixed, all of the submitters will be informed of this. (Note, however, that emails sent to one bug report's submitter won't automatically be sent to the other report's submitter.) For more details on the technicalities of the merge command and its relative, the unmerge command, see the BTS control server documentation.

5. The bug submitter may have forgotten to provide some information, in which case you have to ask them for the required information. You may use the `moreinfo` tag to mark the bug as such. Moreover if you can't reproduce the bug, you tag it `unreproducible`. Anyone who can reproduce the bug is then invited to provide more information on how to reproduce it. After a few months, if this information has not been sent by someone, the bug may be closed.

6. If the bug is related to the packaging, you just fix it. If you are not able to fix it yourself, then tag the bug as `help`. You can also ask for help on &email-debian-devel; or &email-debian-qa;. If it's an upstream problem, you have to forward it to the upstream author. Forwarding a bug is not enough, you have to check at each release if the bug has been fixed or not. If it has, you just close it, otherwise you have to remind the author about it. If you have the required skills you can prepare a patch that fixes the bug and send it to the author at the same time. Make sure to send the patch to the BTS and to tag the bug as `patch`.

7. If you have fixed a bug in your local copy, or if a fix has been committed to the VCS repository, you may tag the bug as `pending` to let people know that the bug is corrected and that it will be closed with the next upload (add the `closes:` in the `changelog`). This is particularly useful if you are several developers working on the same package.

8. Once a corrected package is available in the archive, the bug should be closed indicating the version in which it was fixed. This can be done automatically, read upload-bugfix.

### When bugs are closed by new uploads

As bugs and problems are fixed in your packages, it is your responsibility as the package maintainer to close these bugs. However, you should not close a bug until the package which fixes the bug has been accepted into the Debian archive. Therefore, once you get notification that your updated package has been installed into the archive, you can and should close the bug in the BTS. Also, the bug should be closed with the correct version.

However, it's possible to avoid having to manually close bugs after the upload — just list the fixed bugs in your `debian/changelog` file, following a certain syntax, and the archive maintenance software will close the bugs for you. For example:

    acme-cannon (3.1415) unstable; urgency=low

      * Frobbed with options (closes: Bug#98339)
      * Added safety to prevent operator dismemberment, closes: bug#98765,
        bug#98713, #98714.
      * Added man page. Closes: #98725.

Technically speaking, the following Perl regular expression describes how bug closing changelogs are identified:

      /closes:\s*(?:bug)?\#\s*\d+(?:,\s*(?:bug)?\#\s*\d+)*/ig

We prefer the `closes: #`XXX`` syntax, as it is the most concise entry and the easiest to integrate with the text of the `changelog`. Unless specified different by the `-v`-switch to `dpkg-buildpackage`, only the bugs closed in the most recent changelog entry are closed (basically, exactly the bugs mentioned in the changelog-part in the `.changes` file are closed).

Historically, uploads identified as non-maintainer upload (NMU) were tagged `fixed` instead of being closed, but that practice was ceased with the advent of version-tracking. The same applied to the tag `fixed-in-experimental`.

If you happen to mistype a bug number or forget a bug in the changelog entries, don't hesitate to undo any damage the error caused. To reopen wrongly closed bugs, send a `reopen `XXX`` command to the bug tracking system's control address, &email-bts-control;. To close any remaining bugs that were fixed by your upload, email the `.changes` file to `XXX`-done@&bugs-host;, where `XXX` is the bug number, and put Version: `YYY` and an empty line as the first two lines of the body of the email, where `YYY` is the first version where the bug has been fixed.

Bear in mind that it is not obligatory to close bugs using the changelog as described above. If you simply want to close bugs that don't have anything to do with an upload you made, do it by emailing an explanation to `XXX`-done@&bugs-host;. Do not close bugs in the changelog entry of a version if the changes in that version of the package don't have any bearing on the bug.

For general information on how to write your changelog entries, see bpp-debian-changelog.

### Handling security-related bugs

Due to their sensitive nature, security-related bugs must be handled carefully. The Debian Security Team exists to coordinate this activity, keeping track of outstanding security problems, helping maintainers with security problems or fixing them themselves, sending security advisories, and maintaining `security.debian.org`.

When you become aware of a security-related bug in a Debian package, whether or not you are the maintainer, collect pertinent information about the problem, and promptly contact the security team, preferably by filing a ticket in their Request Tracker. See . Alternatively you may email &email-security-team;. DO NOT UPLOAD any packages for `stable` without contacting the team. Useful information includes, for example:

- Whether or not the bug is already public.

- Which versions of the package are known to be affected by the bug. Check each version that is present in a supported Debian release, as well as `testing` and `unstable`.

- The nature of the fix, if any is available (patches are especially helpful)

- Any fixed packages that you have prepared yourself (send only the `.diff.gz` and `.dsc` files and read bug-security-building first)

- Any assistance you can provide to help with testing (exploits, regression testing, etc.)

- Any information needed for the advisory (see bug-security-advisories)

As the maintainer of the package, you have the responsibility to maintain it, even in the stable release. You are in the best position to evaluate patches and test updated packages, so please see the sections below on how to prepare packages for the Security Team to handle.

#### The Security Tracker

The security team maintains a central database, the Debian Security Tracker. This contains all public information that is known about security issues: which packages and versions are affected or fixed, and thus whether stable, testing and/or unstable are vulnerable. Information that is still confidential is not added to the tracker.

You can search it for a specific issue, but also on package name. Look for your package to see which issues are still open. If you can, please provide more information about those issues, or help to address them in your package. Instructions are on the tracker web pages.

#### Confidentiality

Unlike most other activities within Debian, information about security issues must sometimes be kept private for a time. This allows software distributors to coordinate their disclosure in order to minimize their users' exposure. Whether this is the case depends on the nature of the problem and corresponding fix, and whether it is already a matter of public knowledge.

There are several ways developers can learn of a security problem:

- they notice it on a public forum (mailing list, web site, etc.)

- someone files a bug report

- someone informs them via private email

In the first two cases, the information is public and it is important to have a fix as soon as possible. In the last case, however, it might not be public information. In that case there are a few possible options for dealing with the problem:

- If the security exposure is minor, there is sometimes no need to keep the problem a secret and a fix should be made and released.

- If the problem is severe, it is preferable to share the information with other vendors and coordinate a release. The security team keeps in contact with the various organizations and individuals and can take care of that.

In all cases if the person who reports the problem asks that it not be disclosed, such requests should be honored, with the obvious exception of informing the security team in order that a fix may be produced for a stable release of Debian. When sending confidential information to the security team, be sure to mention this fact.

Please note that if secrecy is needed you may not upload a fix to `unstable` (or anywhere else, such as a public VCS repository). It is not sufficient to obfuscate the details of the change, as the code itself is public, and can (and will) be examined by the general public.

There are two reasons for releasing information even though secrecy is requested: the problem has been known for a while, or the problem or exploit has become public.

The Security Team has a PGP-key to enable encrypted communication about sensitive issues. See the Security Team FAQ for details.

#### Security Advisories

Security advisories are only issued for the current, released stable distribution, and not for `testing` or `unstable`. When released, advisories are sent to the &email-debian-security-announce; mailing list and posted on the security web page. Security advisories are written and posted by the security team. However they certainly do not mind if a maintainer can supply some of the information for them, or write part of the text. Information that should be in an advisory includes:

- A description of the problem and its scope, including:

  - The type of problem (privilege escalation, denial of service, etc.)

  - What privileges may be gained, and by whom (if any)

  - How it can be exploited

  - Whether it is remotely or locally exploitable

  - How the problem was fixed

  This information allows users to assess the threat to their systems.

- Version numbers of affected packages

- Version numbers of fixed packages

- Information on where to obtain the updated packages (usually from the Debian security archive)

- References to upstream advisories, CVE identifiers, and any other information useful in cross-referencing the vulnerability

#### Preparing packages to address security issues

One way that you can assist the security team in their duties is to provide them with fixed packages suitable for a security advisory for the stable Debian release.

When an update is made to the stable release, care must be taken to avoid changing system behavior or introducing new bugs. In order to do this, make as few changes as possible to fix the bug. Users and administrators rely on the exact behavior of a release once it is made, so any change that is made might break someone's system. This is especially true of libraries: make sure you never change the API or ABI, no matter how small the change.

This means that moving to a new upstream version is not a good solution. Instead, the relevant changes should be back-ported to the version present in the current stable Debian release. Generally, upstream maintainers are willing to help if needed. If not, the Debian security team may be able to help.

In some cases, it is not possible to back-port a security fix, for example when large amounts of source code need to be modified or rewritten. If this happens, it may be necessary to move to a new upstream version. However, this is only done in extreme situations, and you must always coordinate that with the security team beforehand.

Related to this is another important guideline: always test your changes. If you have an exploit available, try it and see if it indeed succeeds on the unpatched package and fails on the fixed package. Test other, normal actions as well, as sometimes a security fix can break seemingly unrelated features in subtle ways.

Do NOT include any changes in your package which are not directly related to fixing the vulnerability. These will only need to be reverted, and this wastes time. If there are other bugs in your package that you would like to fix, make an upload to proposed-updates in the usual way, after the security advisory is issued. The security update mechanism is not a means for introducing changes to your package which would otherwise be rejected from the stable release, so please do not attempt to do this.

Review and test your changes as much as possible. Check the differences from the previous version repeatedly (`interdiff` from the `patchutils` package and `debdiff` from `devscripts` are useful tools for this, see debdiff).

Be sure to verify the following items:

- Target the right distribution in your `debian/changelog`: `codename``-security` (e.g. `wheezy-security`). Do not target `distribution``-proposed-updates` or `stable`!

- The upload should have urgency=high.

- Make descriptive, meaningful changelog entries. Others will rely on them to determine whether a particular bug was fixed. Add `closes:` statements for any Debian bugs filed. Always include an external reference, preferably a CVE identifier, so that it can be cross-referenced. However, if a CVE identifier has not yet been assigned, do not wait for it but continue the process. The identifier can be cross-referenced later.

- Make sure the version number is proper. It must be greater than the current package, but less than package versions in later distributions. If in doubt, test it with `dpkg --compare-versions`. Be careful not to re-use a version number that you have already used for a previous upload, or one that conflicts with a binNMU. The convention is to append `+deb` `X` `u1` (where `X` is the major release number), e.g. `1:2.4.3-4+deb7u1`, of course increasing 1 for any subsequent uploads.

- Unless the upstream source has been uploaded to `security.debian.org` before (by a previous security update), build the upload with full upstream source (`dpkg-buildpackage -sa`). If there has been a previous upload to `security.debian.org` with the same upstream version, you may upload without upstream source (`dpkg-buildpackage -sd`).

- Be sure to use the exact same `*.orig.tar.{gz,bz2,xz}` as used in the normal archive, otherwise it is not possible to move the security fix into the main archives later.

- Build the package on a clean system which only has packages installed from the distribution you are building for. If you do not have such a system yourself, you can use a debian.org machine (see server-machines) or setup a chroot (see pbuilder and debootstrap).

#### Uploading the fixed package

Do NOT upload a package to the security upload queue (on `security-master.debian.org`) without prior authorization from the security team. If the package does not exactly meet the team's requirements, it will cause many problems and delays in dealing with the unwanted upload.

Do NOT upload your fix to `proposed-updates` without coordinating with the security team. Packages from `security.debian.org` will be copied into the `proposed-updates` directory automatically. If a package with the same or a higher version number is already installed into the archive, the security update will be rejected by the archive system. That way, the stable distribution will end up without a security update for this package instead.

Once you have created and tested the new package and it has been approved by the security team, it needs to be uploaded so that it can be installed in the archives. For security uploads, the place to upload to is `ftp://security-master.debian.org/pub/SecurityUploadQueue/`.

Once an upload to the security queue has been accepted, the package will automatically be built for all architectures and stored for verification by the security team.

Uploads which are waiting for acceptance or verification are only accessible by the security team. This is necessary since there might be fixes for security problems that cannot be disclosed yet.

If a member of the security team accepts a package, it will be installed on `security.debian.org` as well as proposed for the proper `distribution``-proposed-updates` on `&ftp-master-host;`.

## Moving, removing, renaming, orphaning, adopting, and reintroducing packages

Some archive manipulation operations are not automated in the Debian upload process. These procedures should be manually followed by maintainers. This chapter gives guidelines on what to do in these cases.

### Moving packages

Sometimes a package will change its section. For instance, a package from the `non-free` section might be GPL'd in a later version, in which case the package should be moved to `main' or `contrib'.

See the Debian Policy Manual for guidelines on what section a package belongs in.

If you need to change the section for one of your packages, change the package control information to place the package in the desired section, and re-upload the package (see the Debian Policy Manual for details). You must ensure that you include the `.orig.tar.{gz,bz2,xz}` in your upload (even if you are not uploading a new upstream version), or it will not appear in the new section together with the rest of the package. If your new section is valid, it will be moved automatically. If it does not, then contact the ftpmasters in order to understand what happened.

If, on the other hand, you need to change the `subsection` of one of your packages (e.g., ``devel'', ``admin''), the procedure is slightly different. Correct the subsection as found in the control file of the package, and re-upload that. Also, you'll need to get the override file updated, as described in override-file.

### Removing packages

If for some reason you want to completely remove a package (say, if it is an old compatibility library which is no longer required), you need to file a bug against `&ftp-debian-org;` asking that the package be removed; as all bugs, this bug should normally have normal severity. The bug title should be in the form `RM: `package` `[architecture list]` -- `reason``, where `package` is the package to be removed and `reason` is a short summary of the reason for the removal request. `[architecture list]` is optional and only needed if the removal request only applies to some architectures, not all. Note that the `reportbug` will create a title conforming to these rules when you use it to report a bug against the `&ftp-debian-org;` pseudo-package.

If you want to remove a package you maintain, you should note this in the bug title by prepending `ROM` (Request Of Maintainer). There are several other standard acronyms used in the reasoning for a package removal, see for a complete list. That page also provides a convenient overview of pending removal requests.

Note that removals can only be done for the `unstable`, `experimental` and `stable` distribution. Packages are not removed from `testing` directly. Rather, they will be removed automatically after the package has been removed from `unstable` and no package in `testing` depends on it. (Removals from `testing` are possible though by filing a removal bug report against the `&release-debian-org;` pseudo-package. See the section removals.)

There is one exception when an explicit removal request is not necessary: If a (source or binary) package is no longer built from source, it will be removed semi-automatically. For a binary-package, this means if there is no longer any source package producing this binary package; if the binary package is just no longer produced on some architectures, a removal request is still necessary. For a source-package, this means that all binary packages it refers to have been taken over by another source package.

In your removal request, you have to detail the reasons justifying the request. This is to avoid unwanted removals and to keep a trace of why a package has been removed. For example, you can provide the name of the package that supersedes the one to be removed.

Usually you only ask for the removal of a package maintained by yourself. If you want to remove another package, you have to get the approval of its maintainer. Should the package be orphaned and thus have no maintainer, you should first discuss the removal request on &email-debian-qa;. If there is a consensus that the package should be removed, you should reassign and retitle the `O:` bug filed against the `wnpp` package instead of filing a new bug as removal request.

Further information relating to these and other package removal related topics may be found at and .

If in doubt concerning whether a package is disposable, email &email-debian-devel; asking for opinions. Also of interest is the `apt-cache` program from the `apt` package. When invoked as `apt-cache showpkg `package``, the program will show details for `package`, including reverse depends. Other useful programs include `apt-cache rdepends`, `apt-rdepends`, `build-rdeps` (in the `devscripts` package) and `grep-dctrl`. Removal of orphaned packages is discussed on &email-debian-qa;.

Once the package has been removed, the package's bugs should be handled. They should either be reassigned to another package in the case where the actual code has evolved into another package (e.g. `libfoo12` was removed because `libfoo13` supersedes it) or closed if the software is simply no longer part of Debian. When closing the bugs, to avoid marking the bugs as fixed in versions of the packages in previous Debian releases, they should be marked as fixed in the version `<most-recent-version-ever-in-Debian>+rm`.

#### Removing packages from `Incoming`

In the past, it was possible to remove packages from `incoming`. However, with the introduction of the new incoming system, this is no longer possible. Instead, you have to upload a new revision of your package with a higher version than the package you want to replace. Both versions will be installed in the archive but only the higher version will actually be available in `unstable` since the previous version will immediately be replaced by the higher. However, if you do proper testing of your packages, the need to replace a package should not occur too often anyway.

### Replacing or renaming packages

When the upstream maintainers for one of your packages chose to rename their software (or you made a mistake naming your package), you should follow a two-step process to rename it. In the first step, change the `debian/control` file to reflect the new name and to replace, provide and conflict with the obsolete package name (see the Debian Policy Manual for details). Please note that you should only add a `Provides` relation if all packages depending on the obsolete package name continue to work after the renaming. Once you've uploaded the package and the package has moved into the archive, file a bug against `&ftp-debian-org;` asking to remove the package with the obsolete name (see removing-pkgs). Do not forget to properly reassign the package's bugs at the same time.

At other times, you may make a mistake in constructing your package and wish to replace it. The only way to do this is to increase the version number and upload a new version. The old version will be expired in the usual manner. Note that this applies to each part of your package, including the sources: if you wish to replace the upstream source tarball of your package, you will need to upload it with a different version. An easy possibility is to replace `foo_1.00.orig.tar.gz` with `foo_1.00+0.orig.tar.gz` or `foo_1.00.orig.tar.bz2`. This restriction gives each file on the ftp site a unique name, which helps to ensure consistency across the mirror network.

### Orphaning a package

If you can no longer maintain a package, you need to inform others, and see that the package is marked as orphaned. You should set the package maintainer to `Debian QA Group &orphan-address;` and submit a bug report against the pseudo package `wnpp`. The bug report should be titled `O: `package` -- `short description`` indicating that the package is now orphaned. The severity of the bug should be set to `normal`; if the package has a priority of standard or higher, it should be set to important. If you feel it's necessary, send a copy to &email-debian-devel; by putting the address in the X-Debbugs-CC: header of the message (no, don't use CC:, because that way the message's subject won't indicate the bug number).

If you just intend to give the package away, but you can keep maintainership for the moment, then you should instead submit a bug against `wnpp` and title it `RFA: `package` -- `short description``. `RFA` stands for `Request For Adoption`.

More information is on the WNPP web pages.

### Adopting a package

A list of packages in need of a new maintainer is available in the Work-Needing and Prospective Packages list (WNPP). If you wish to take over maintenance of any of the packages listed in the WNPP, please take a look at the aforementioned page for information and procedures.

It is not OK to simply take over a package that you feel is neglected — that would be package hijacking. You can, of course, contact the current maintainer and ask them if you may take over the package. If you have reason to believe a maintainer has gone AWOL (absent without leave), see mia-qa.

Generally, you may not take over the package without the assent of the current maintainer. Even if they ignore you, that is still not grounds to take over a package. Complaints about maintainers should be brought up on the developers' mailing list. If the discussion doesn't end with a positive conclusion, and the issue is of a technical nature, consider bringing it to the attention of the technical committee (see the technical committee web page for more information).

If you take over an old package, you probably want to be listed as the package's official maintainer in the bug system. This will happen automatically once you upload a new version with an updated `Maintainer` field, although it can take a few hours after the upload is done. If you do not expect to upload a new version for a while, you can use pkg-tracking-system to get the bug reports. However, make sure that the old maintainer has no problem with the fact that they will continue to receive the bugs during that time.

### Reintroducing packages

Packages are often removed due to release-critical bugs, absent maintainers, too few users or poor quality in general. While the process of reintroduction is similar to the initial packaging process, you can avoid some pitfalls by doing some historical research first.

You should check why the package was removed in the first place. This information can be found in the removal item in the news section of the PTS page for the package or by browsing the log of removals. The removal bug will tell you why the package was removed and will give some indication of what you will need to work on in order to reintroduce the package. It may indicate that the best way forward is to switch to some other piece of software instead of reintroducing the package.

It may be appropriate to contact the former maintainers to find out if they are working on reintroducing the package, interested in co-maintaining the package or interested in sponsoring the package if needed.

You should do all the things required before introducing new packages (newpackage).

You should base your work on the latest packaging available that is suitable. That might be the latest version from `unstable`, which will still be present in the snapshot archive.

The version control system used by the previous maintainer might contain useful changes, so it might be a good idea to have a look there. Check if the `control` file of the previous package contained any headers linking to the version control system for the package and if it still exists.

Package removals from `unstable` (not `testing`, `stable` or `oldstable`) trigger the closing of all bugs related to the package. You should look through all the closed bugs (including archived bugs) and unarchive and reopen any that were closed in a version ending in `+rm` and still apply. Any that no longer apply should be marked as fixed in the correct version if that is known.

## Porting and being ported

Debian supports an ever-increasing number of architectures. Even if you are not a porter, and you don't use any architecture but one, it is part of your duty as a maintainer to be aware of issues of portability. Therefore, even if you are not a porter, you should read most of this chapter.

Porting is the act of building Debian packages for architectures that are different from the original architecture of the package maintainer's binary package. It is a unique and essential activity. In fact, porters do most of the actual compiling of Debian packages. For instance, when a maintainer uploads a (portable) source packages with binaries for the `i386` architecture, it will be built for each of the other architectures, amounting to &number-of-arches; more builds.

### Being kind to porters

Porters have a difficult and unique task, since they are required to deal with a large volume of packages. Ideally, every source package should build right out of the box. Unfortunately, this is often not the case. This section contains a checklist of ``gotchas'' often committed by Debian maintainers — common problems which often stymie porters, and make their jobs unnecessarily difficult.

The first and most important thing is to respond quickly to bug or issues raised by porters. Please treat porters with courtesy, as if they were in fact co-maintainers of your package (which, in a way, they are). Please be tolerant of succinct or even unclear bug reports; do your best to hunt down whatever the problem is.

By far, most of the problems encountered by porters are caused by packaging bugs in the source packages. Here is a checklist of things you should check or be aware of.

1. Make sure that your `Build-Depends` and `Build-Depends-Indep` settings in `debian/control` are set properly. The best way to validate this is to use the `debootstrap` package to create an `unstable` chroot environment (see debootstrap). Within that chrooted environment, install the `build-essential` package and any package dependencies mentioned in `Build-Depends` and/or `Build-Depends-Indep`. Finally, try building your package within that chrooted environment. These steps can be automated by the use of the `pbuilder` program which is provided by the package of the same name (see pbuilder).

   If you can't set up a proper chroot, `dpkg-depcheck` may be of assistance (see dpkg-depcheck).

   See the Debian Policy Manual for instructions on setting build dependencies.

2. Don't set architecture to a value other than `all` or `any` unless you really mean it. In too many cases, maintainers don't follow the instructions in the Debian Policy Manual. Setting your architecture to only one architecture (such as `i386` or `amd64`) is usually incorrect.

3. Make sure your source package is correct. Do `dpkg-source -x `package`.dsc` to make sure your source package unpacks properly. Then, in there, try building your package from scratch with `dpkg-buildpackage`.

4. Make sure you don't ship your source package with the `debian/files` or `debian/substvars` files. They should be removed by the `clean` target of `debian/rules`.

5. Make sure you don't rely on locally installed or hacked configurations or programs. For instance, you should never be calling programs in `/usr/local/bin` or the like. Try not to rely on programs being setup in a special way. Try building your package on another machine, even if it's the same architecture.

6. Don't depend on the package you're building being installed already (a sub-case of the above issue). There are, of course, exceptions to this rule, but be aware that any case like this needs manual bootstrapping and cannot be done by automated package builders.

7. Don't rely on the compiler being a certain version, if possible. If not, then make sure your build dependencies reflect the restrictions, although you are probably asking for trouble, since different architectures sometimes standardize on different compilers.

8. Make sure your `debian/rules` contains separate `binary-arch` and `binary-indep` targets, as the Debian Policy Manual requires. Make sure that both targets work independently, that is, that you can call the target without having called the other before. To test this, try to run `dpkg-buildpackage -B`.

### Guidelines for porter uploads

If the package builds out of the box for the architecture to be ported to, you are in luck and your job is easy. This section applies to that case; it describes how to build and upload your binary package so that it is properly installed into the archive. If you do have to patch the package in order to get it to compile for the other architecture, you are actually doing a source NMU, so consult nmu-guidelines instead.

For a porter upload, no changes are being made to the source. You do not need to touch any of the files in the source package. This includes `debian/changelog`.

The way to invoke `dpkg-buildpackage` is as `dpkg-buildpackage -B -m`porter-email``. Of course, set `porter-email` to your email address. This will do a binary-only build of only the architecture-dependent portions of the package, using the `binary-arch` target in `debian/rules`.

If you are working on a Debian machine for your porting efforts and you need to sign your upload locally for its acceptance in the archive, you can run `debsign` on your `.changes` file to have it signed conveniently, or use the remote signing mode of `dpkg-sig`.

#### Recompilation or binary-only NMU

Sometimes the initial porter upload is problematic because the environment in which the package was built was not good enough (outdated or obsolete library, bad compiler, etc.). Then you may just need to recompile it in an updated environment. However, you have to bump the version number in this case, so that the old bad package can be replaced in the Debian archive (`dak` refuses to install new packages if they don't have a version number greater than the currently available one).

You have to make sure that your binary-only NMU doesn't render the package uninstallable. This could happen when a source package generates arch-dependent and arch-independent packages that have inter-dependencies generated using dpkg's substitution variable `$(Source-Version)`.

Despite the required modification of the changelog, these are called binary-only NMUs — there is no need in this case to trigger all other architectures to consider themselves out of date or requiring recompilation.

Such recompilations require special ``magic'' version numbering, so that the archive maintenance tools recognize that, even though there is a new Debian version, there is no corresponding source update. If you get this wrong, the archive maintainers will reject your upload (due to lack of corresponding source code).

The ``magic'' for a recompilation-only NMU is triggered by using a suffix appended to the package version number, following the form `b`number``. For instance, if the latest version you are recompiling against was version `2.9-3`, your binary-only NMU should carry a version of `2.9-3+b1`. If the latest version was `3.4+b1` (i.e, a native package with a previous recompilation NMU), your binary-only NMU should have a version number of `3.4+b2`.

In the past, such NMUs used the third-level number on the Debian part of the revision to denote their recompilation-only status; however, this syntax was ambiguous with native packages and did not allow proper ordering of recompile-only NMUs, source NMUs, and security NMUs on the same package, and has therefore been abandoned in favor of this new syntax.

Similar to initial porter uploads, the correct way of invoking `dpkg-buildpackage` is `dpkg-buildpackage -B` to only build the architecture-dependent parts of the package.

#### When to do a source NMU if you are a porter

Porters doing a source NMU generally follow the guidelines found in nmu, just like non-porters. However, it is expected that the wait cycle for a porter's source NMU is smaller than for a non-porter, since porters have to cope with a large quantity of packages. Again, the situation varies depending on the distribution they are uploading to. It also varies whether the architecture is a candidate for inclusion into the next stable release; the release managers decide and announce which architectures are candidates.

If you are a porter doing an NMU for `unstable`, the above guidelines for porting should be followed, with two variations. Firstly, the acceptable waiting period — the time between when the bug is submitted to the BTS and when it is OK to do an NMU — is seven days for porters working on the `unstable` distribution. This period can be shortened if the problem is critical and imposes hardship on the porting effort, at the discretion of the porter group. (Remember, none of this is Policy, just mutually agreed upon guidelines.) For uploads to `stable` or `testing`, please coordinate with the appropriate release team first.

Secondly, porters doing source NMUs should make sure that the bug they submit to the BTS should be of severity `serious` or greater. This ensures that a single source package can be used to compile every supported Debian architecture by release time. It is very important that we have one version of the binary and source package for all architectures in order to comply with many licenses.

Porters should try to avoid patches which simply kludge around bugs in the current version of the compile environment, kernel, or libc. Sometimes such kludges can't be helped. If you have to kludge around compiler bugs and the like, make sure you `#ifdef` your work properly; also, document your kludge so that people know to remove it once the external problems have been fixed.

Porters may also have an unofficial location where they can put the results of their work during the waiting period. This helps others running the port have the benefit of the porter's work, even during the waiting period. Of course, such locations have no official blessing or status, so buyer beware.

### Porting infrastructure and automation

There is infrastructure and several tools to help automate package porting. This section contains a brief overview of this automation and porting to these tools; see the package documentation or references for full information.

#### Mailing lists and web pages

Web pages containing the status of each port can be found at .

Each port of Debian has a mailing list. The list of porting mailing lists can be found at . These lists are used to coordinate porters, and to connect the users of a given port with the porters.

#### Porter tools

Descriptions of several porting tools can be found in tools-porting.

#### `wanna-build`

The `wanna-build` system is used as a distributed, client-server build distribution system. It is usually used in conjunction with build daemons running the `buildd` program. `Build daemons` are ``slave'' hosts which contact the central `wanna-build` system to receive a list of packages that need to be built.

`wanna-build` is not yet available as a package; however, all Debian porting efforts are using it for automated package building. The tool used to do the actual package builds, `sbuild` is available as a package, see its description in sbuild. Please note that the packaged version is not the same as the one used on build daemons, but it is close enough to reproduce problems.

Most of the data produced by `wanna-build` which is generally useful to porters is available on the web at . This data includes nightly updated statistics, queueing information and logs for build attempts.

We are quite proud of this system, since it has so many possible uses. Independent development groups can use the system for different sub-flavors of Debian, which may or may not really be of general interest (for instance, a flavor of Debian built with `gcc` bounds checking). It will also enable Debian to recompile entire distributions quickly.

The wanna-build team, in charge of the buildds, can be reached at `debian-wb-team@lists.debian.org`. To determine who (wanna-build team, release team) and how (mail, BTS) to contact, refer to .

When requesting binNMUs or give-backs (retries after a failed build), please use the format described at .

### When your package is not portable

Some packages still have issues with building and/or working on some of the architectures supported by Debian, and cannot be ported at all, or not within a reasonable amount of time. An example is a package that is SVGA-specific (only available for `i386` and `amd64`), or uses other hardware-specific features not supported on all architectures.

In order to prevent broken packages from being uploaded to the archive, and wasting buildd time, you need to do a few things:

- First, make sure your package does fail to build on architectures that it cannot support. There are a few ways to achieve this. The preferred way is to have a small testsuite during build time that will test the functionality, and fail if it doesn't work. This is a good idea anyway, as this will prevent (some) broken uploads on all architectures, and also will allow the package to build as soon as the required functionality is available.

  Additionally, if you believe the list of supported architectures is pretty constant, you should change `any` to a list of supported architectures in `debian/control`. This way, the build will fail also, and indicate this to a human reader without actually trying.

- In order to prevent autobuilders from needlessly trying to build your package, it must be included in `Packages-arch-specific`, a list used by the `wanna-build` script. The current version is available as ; please see the top of the file for whom to contact for changes.

Please note that it is insufficient to only add your package to `Packages-arch-specific` without making it fail to build on unsupported architectures: A porter or any other person trying to build your package might accidently upload it without noticing it doesn't work. If in the past some binary packages were uploaded on unsupported architectures, request their removal by filing a bug against `ftp.debian.org`.

### Marking non-free packages as auto-buildable

By default packages from the `non-free` section are not built by the autobuilder network (mostly because the license of the packages could disapprove). To enable a package to be build you need to perform the following steps:

1. Check whether it is legally allowed and technically possible to auto-build the package;

2. Add `XS-Autobuild: yes` into the header part of `debian/control`;

3. Send an email to &email-nonfree-release; and explain why the package can legitimately and technically be auto-built.

## Non-Maintainer Uploads (NMUs)

Every package has one or more maintainers. Normally, these are the people who work on and upload new versions of the package. In some situations, it is useful that other developers can upload a new version as well, for example if they want to fix a bug in a package they don't maintain, when the maintainer needs help to respond to issues. Such uploads are called Non-Maintainer Uploads (NMU).

### When and how to do an NMU

Before doing an NMU, consider the following questions:

- Does your NMU really fix bugs? Fixing cosmetic issues or changing the packaging style in NMUs is discouraged.

- Did you give enough time to the maintainer? When was the bug reported to the BTS? Being busy for a week or two isn't unusual. Is the bug so severe that it needs to be fixed right now, or can it wait a few more days?

- How confident are you about your changes? Please remember the Hippocratic Oath: "Above all, do no harm." It is better to leave a package with an open grave bug than applying a non-functional patch, or one that hides the bug instead of resolving it. If you are not 100% sure of what you did, it might be a good idea to seek advice from others. Remember that if you break something in your NMU, many people will be very unhappy about it.

- Have you clearly expressed your intention to NMU, at least in the BTS? It is also a good idea to try to contact the maintainer by other means (private email, IRC).

- If the maintainer is usually active and responsive, have you tried to contact them? In general it should be considered preferable that maintainers take care of an issue themselves and that they are given the chance to review and correct your patch, because they can be expected to be more aware of potential issues which an NMUer might miss. It is often a better use of everyone's time if the maintainer is given an opportunity to upload a fix on their own.

When doing an NMU, you must first make sure that your intention to NMU is clear. Then, you must send a patch with the differences between the current package and your proposed NMU to the BTS. The `nmudiff` script in the `devscripts` package might be helpful.

While preparing the patch, you should better be aware of any package-specific practices that the maintainer might be using. Taking them into account reduces the burden of integrating your changes into the normal package workflow and thus increases the chances that integration will happen. A good place where to look for for possible package-specific practices is `debian/README.source`.

Unless you have an excellent reason not to do so, you must then give some time to the maintainer to react (for example, by uploading to the `DELAYED` queue). Here are some recommended values to use for delays:

- Upload fixing only release-critical bugs older than 7 days, with no maintainer activity on the bug for 7 days and no indication that a fix is in progress: 0 days

- Upload fixing only release-critical bugs older than 7 days: 2 days

- Upload fixing only release-critical and important bugs: 5 days

- Other NMUs: 10 days

Those delays are only examples. In some cases, such as uploads fixing security issues, or fixes for trivial bugs that blocking a transition, it is desirable that the fixed package reaches `unstable` sooner.

Sometimes, release managers decide to allow NMUs with shorter delays for a subset of bugs (e.g release-critical bugs older than 7 days). Also, some maintainers list themselves in the Low Threshold NMU list, and accept that NMUs are uploaded without delay. But even in those cases, it's still a good idea to give the maintainer a few days to react before you upload, especially if the patch wasn't available in the BTS before, or if you know that the maintainer is generally active.

After you upload an NMU, you are responsible for the possible problems that you might have introduced. You must keep an eye on the package (subscribing to the package on the PTS is a good way to achieve this).

This is not a license to perform NMUs thoughtlessly. If you NMU when it is clear that the maintainers are active and would have acknowledged a patch in a timely manner, or if you ignore the recommendations of this document, your upload might be a cause of conflict with the maintainer. You should always be prepared to defend the wisdom of any NMU you perform on its own merits.

### NMUs and `debian/changelog`

Just like any other (source) upload, NMUs must add an entry to `debian/changelog`, telling what has changed with this upload. The first line of this entry must explicitely mention that this upload is an NMU, e.g.:

      * Non-maintainer upload.

The way to version NMUs differs for native and non-native packages.

If the package is a native package (without a Debian revision in the version number), the version must be the version of the last maintainer upload, plus `+nmu`X``, where `X` is a counter starting at `1`. If the last upload was also an NMU, the counter should be increased. For example, if the current version is `1.5`, then an NMU would get version `1.5+nmu1`.

If the package is not a native package, you should add a minor version number to the Debian revision part of the version number (the portion after the last hyphen). This extra number must start at `1`. For example, if the current version is `1.5-2`, then an NMU would get version `1.5-2.1`. If a new upstream version is packaged in the NMU, the Debian revision is set to `0`, for example `1.6-0.1`.

In both cases, if the last upload was also an NMU, the counter should be increased. For example, if the current version is `1.5+nmu3` (a native package which has already been NMUed), the NMU would get version `1.5+nmu4`.

A special versioning scheme is needed to avoid disrupting the maintainer's work, since using an integer for the Debian revision will potentially conflict with a maintainer upload already in preparation at the time of an NMU, or even one sitting in the ftp NEW queue. It also has the benefit of making it visually clear that a package in the archive was not made by the official maintainer.

If you upload a package to testing or stable, you sometimes need to "fork" the version number tree. This is the case for security uploads, for example. For this, a version of the form `+deb`X`u`Y`` should be used, where `X` is the major release number, and `Y` is a counter starting at `1`. For example, while Wheezy (Debian 7.0) is stable, a security NMU to stable for a package at version `1.5-3` would have version `1.5-3+deb7u1`, whereas a security NMU to Jessie would get version `1.5-3+deb8u1`.

### Using the `DELAYED/` queue

Having to wait for a response after you request permission to NMU is inefficient, because it costs the NMUer a context switch to come back to the issue. The `DELAYED` queue (see delayed-incoming) allows the developer doing the NMU to perform all the necessary tasks at the same time. For instance, instead of telling the maintainer that you will upload the updated package in 7 days, you should upload the package to `DELAYED/7` and tell the maintainer that they have 7 days to react. During this time, the maintainer can ask you to delay the upload some more, or cancel your upload.

The `DELAYED` queue should not be used to put additional pressure on the maintainer. In particular, it's important that you are available to cancel or delay the upload before the delay expires since the maintainer cannot cancel the upload themselves.

If you make an NMU to `DELAYED` and the maintainer updates the package before the delay expires, your upload will be rejected because a newer version is already available in the archive. Ideally, the maintainer will take care to include your proposed changes (or at least a solution for the problems they address) in that upload.

### NMUs from the maintainer's point of view

When someone NMUs your package, this means they want to help you to keep it in good shape. This gives users fixed packages faster. You can consider asking the NMUer to become a co-maintainer of the package. Receiving an NMU on a package is not a bad thing; it just means that the package is interesting enough for other people to work on it.

To acknowledge an NMU, include its changes and changelog entry in your next maintainer upload. If you do not acknowledge the NMU by including the NMU changelog entry in your changelog, the bugs will remain closed in the BTS but will be listed as affecting your maintainer version of the package.

### Source NMUs vs Binary-only NMUs (binNMUs)

The full name of an NMU is source NMU. There is also another type, namely the binary-only NMU, or binNMU. A binNMU is also a package upload by someone other than the package's maintainer. However, it is a binary-only upload.

When a library (or other dependency) is updated, the packages using it may need to be rebuilt. Since no changes to the source are needed, the same source package is used.

BinNMUs are usually triggered on the buildds by wanna-build. An entry is added to `debian/changelog`, explaining why the upload was needed and increasing the version number as described in binary-only-nmu. This entry should not be included in the next upload.

Buildds upload packages for their architecture to the archive as binary-only uploads. Strictly speaking, these are binNMUs. However, they are not normally called NMU, and they don't add an entry to `debian/changelog`.

### NMUs vs QA uploads

NMUs are uploads of packages by somebody else than their assigned maintainer. There is another type of upload where the uploaded package is not yours: QA uploads. QA uploads are uploads of orphaned packages.

QA uploads are very much like normal maintainer uploads: they may fix anything, even minor issues; the version numbering is normal, and there is no need to use a delayed upload. The difference is that you are not listed as the `Maintainer` or `Uploader` for the package. Also, the changelog entry of a QA upload has a special first line:

     * QA upload.

If you want to do an NMU, and it seems that the maintainer is not active, it is wise to check if the package is orphaned (this information is displayed on the package's Package Tracking System page). When doing the first QA upload to an orphaned package, the maintainer should be set to `Debian QA Group <packages@qa.debian.org>`. Orphaned packages which did not yet have a QA upload still have their old maintainer set. There is a list of them at .

Instead of doing a QA upload, you can also consider adopting the package by making yourself the maintainer. You don't need permission from anybody to adopt an orphaned package, you can just set yourself as maintainer and upload the new version (see adopting).

### NMUs vs team uploads

Sometimes you are fixing and/or updating a package because you are member of a packaging team (which uses a mailing list as `Maintainer` or `Uploader`, see collaborative-maint) but you don't want to add yourself to `Uploaders` because you do not plan to contribute regularly to this specific package. If it conforms with your team's policy, you can perform a normal upload without being listed directly as `Maintainer` or `Uploader`. In that case, you should start your changelog entry with the following line:

     * Team upload.

## Collaborative maintenance

Collaborative maintenance is a term describing the sharing of Debian package maintenance duties by several people. This collaboration is almost always a good idea, since it generally results in higher quality and faster bug fix turnaround times. It is strongly recommended that packages with a priority of `standard` or which are part of the base set have co-maintainers.

Generally there is a primary maintainer and one or more co-maintainers. The primary maintainer is the person whose name is listed in the `Maintainer` field of the `debian/control` file. Co-maintainers are all the other maintainers, usually listed in the `Uploaders` field of the `debian/control` file.

In its most basic form, the process of adding a new co-maintainer is quite easy:

- Setup the co-maintainer with access to the sources you build the package from. Generally this implies you are using a network-capable version control system, such as `CVS` or `Subversion`. Alioth (see alioth) provides such tools, amongst others.

- Add the co-maintainer's correct maintainer name and address to the `Uploaders` field in the first paragraph of the `debian/control` file.

      Uploaders: John Buzz <jbuzz@debian.org>, Adam Rex <arex@debian.org>

- Using the PTS (pkg-tracking-system), the co-maintainers should subscribe themselves to the appropriate source package.

Another form of collaborative maintenance is team maintenance, which is recommended if you maintain several packages with the same group of developers. In that case, the `Maintainer` and `Uploaders` field of each package must be managed with care. It is recommended to choose between one of the two following schemes:

1. Put the team member mainly responsible for the package in the `Maintainer` field. In the `Uploaders`, put the mailing list address, and the team members who care for the package.

2. Put the mailing list address in the `Maintainer` field. In the `Uploaders` field, put the team members who care for the package. In this case, you must make sure the mailing list accept bug reports without any human interaction (like moderation for non-subscribers).

In any case, it is a bad idea to automatically put all team members in the `Uploaders` field. It clutters the Developer's Package Overview listing (see ddpo) with packages one doesn't really care for, and creates a false sense of good maintenance. For the same reason, team members do not need to add themselves to the `Uploaders` field just because they are uploading the package once, they can do a “Team upload” (see nmu-team-upload). Conversely, it is a bad idea to keep a package with only the mailing list address as a `Maintainer` and no `Uploaders`.

## The testing distribution

### Basics

Packages are usually installed into the `testing` distribution after they have undergone some degree of `testing` in `unstable`.

They must be in sync on all architectures and mustn't have dependencies that make them uninstallable; they also have to have generally no known release-critical bugs at the time they're installed into `testing`. This way, `testing` should always be close to being a release candidate. Please see below for details.

### Updates from unstable

The scripts that update the `testing` distribution are run twice each day, right after the installation of the updated packages; these scripts are called `britney`. They generate the `Packages` files for the `testing` distribution, but they do so in an intelligent manner; they try to avoid any inconsistency and to use only non-buggy packages.

The inclusion of a package from `unstable` is conditional on the following:

- The package must have been available in `unstable` for 2, 5 or 10 days, depending on the urgency (high, medium or low). Please note that the urgency is sticky, meaning that the highest urgency uploaded since the previous `testing` transition is taken into account;

- It must not have new release-critical bugs (RC bugs affecting the version available in `unstable`, but not affecting the version in `testing`);

- It must be available on all architectures on which it has previously been built in `unstable`. dak ls may be of interest to check that information;

- It must not break any dependency of a package which is already available in `testing`;

- The packages on which it depends must either be available in `testing` or they must be accepted into `testing` at the same time (and they will be if they fulfill all the necessary criteria);

- The phase of the project. I.e. automatic transitions are turned off during the freeze of the `testing` distribution.

To find out whether a package is progressing into `testing` or not, see the `testing` script output on the web page of the testing distribution, or use the program `grep-excuses` which is in the `devscripts` package. This utility can easily be used in a

crontab

5 to keep yourself informed of the progression of your packages into `testing`.

The `update_excuses` file does not always give the precise reason why the package is refused; you may have to find it on your own by looking for what would break with the inclusion of the package. The testing web page gives some more information about the usual problems which may be causing such troubles.

Sometimes, some packages never enter `testing` because the set of interrelationship is too complicated and cannot be sorted out by the scripts. See below for details.

Some further dependency analysis is shown on — but be warned, this page also shows build dependencies which are not considered by britney.

#### Out-of-date

For the `testing` migration script, outdated means: There are different versions in `unstable` for the release architectures (except for the architectures in fuckedarches; fuckedarches is a list of architectures that don't keep up (in `update_out.py`), but currently, it's empty). outdated has nothing whatsoever to do with the architectures this package has in `testing`.

Consider this example:

| alpha | arm
testing | 1 | -
unstable | 1 | 2

The package is out of date on `alpha` in `unstable`, and will not go to `testing`. Removing the package would not help at all, the package is still out of date on `alpha`, and will not propagate to `testing`.

However, if ftp-master removes a package in `unstable` (here on `arm`):

| alpha | arm | hurd-i386
testing | 1 | 1 | -
unstable | 2 | - | 1

In this case, the package is up to date on all release architectures in `unstable` (and the extra `hurd-i386` doesn't matter, as it's not a release architecture).

Sometimes, the question is raised if it is possible to allow packages in that are not yet built on all architectures: No. Just plainly no. (Except if you maintain glibc or so.)

#### Removals from testing

Sometimes, a package is removed to allow another package in: This happens only to allow another package to go in if it's ready in every other sense. Suppose e.g. that `a` cannot be installed with the new version of `b`; then `a` may be removed to allow `b` in.

Of course, there is another reason to remove a package from `testing`: It's just too buggy (and having a single RC-bug is enough to be in this state).

Furthermore, if a package has been removed from `unstable`, and no package in `testing` depends on it any more, then it will automatically be removed.

#### Circular dependencies

A situation which is not handled very well by britney is if package `a` depends on the new version of package `b`, and vice versa.

An example of this is:

| testing | unstable
a | 1; depends: b=1 | 2; depends: b=2
b | 1; depends: a=1 | 2; depends: a=2

Neither package `a` nor package `b` is considered for update.

Currently, this requires some manual hinting from the release team. Please contact them by sending mail to &email-debian-release; if this happens to one of your packages.

#### Influence of package in testing

Generally, there is nothing that the status of a package in `testing` means for transition of the next version from `unstable` to `testing`, with two exceptions: If the RC-bugginess of the package goes down, it may go in even if it is still RC-buggy. The second exception is if the version of the package in `testing` is out of sync on the different arches: Then any arch might just upgrade to the version of the source package; however, this can happen only if the package was previously forced through, the arch is in fuckedarches, or there was no binary package of that arch present in `unstable` at all during the `testing` migration.

In summary this means: The only influence that a package being in `testing` has on a new version of the same package is that the new version might go in easier.

#### Details

If you are interested in details, this is how britney works:

The packages are looked at to determine whether they are valid candidates. This gives the update excuses. The most common reasons why a package is not considered are too young, RC-bugginess, and out of date on some arches. For this part of britney, the release managers have hammers of various sizes, called hints (see below), to force britney to consider a package.

Now, the more complex part happens: Britney tries to update `testing` with the valid candidates. For that, britney tries to add each valid candidate to the testing distribution. If the number of uninstallable packages in `testing` doesn't increase, the package is accepted. From that point on, the accepted package is considered to be part of `testing`, such that all subsequent installability tests include this package. Hints from the release team are processed before or after this main run, depending on the exact type.

If you want to see more details, you can look it up on .

The hints are available via , where you can find the description as well. With the hints, the Debian Release team can block or unblock packages, ease or force packages into `testing`, remove packages from `testing`, approve uploads to testing-proposed-updates or override the urgency.

### Direct updates to testing

The `testing` distribution is fed with packages from `unstable` according to the rules explained above. However, in some cases, it is necessary to upload packages built only for `testing`. For that, you may want to upload to `testing-proposed-updates`.

Keep in mind that packages uploaded there are not automatically processed, they have to go through the hands of the release manager. So you'd better have a good reason to upload there. In order to know what a good reason is in the release managers' eyes, you should read the instructions that they regularly give on &email-debian-devel-announce;.

You should not upload to `testing-proposed-updates` when you can update your packages through `unstable`. If you can't (for example because you have a newer development version in `unstable`), you may use this facility, but it is recommended that you ask for authorization from the release manager first. Even if a package is frozen, updates through `unstable` are possible, if the upload via `unstable` does not pull in any new dependencies.

Version numbers are usually selected by adding the codename of the `testing` distribution and a running number, like `1.2squeeze1` for the first upload through `testing-proposed-updates` of package version `1.2`.

Please make sure you didn't miss any of these items in your upload:

- Make sure that your package really needs to go through `testing-proposed-updates`, and can't go through `unstable`;

- Make sure that you included only the minimal amount of changes;

- Make sure that you included an appropriate explanation in the changelog;

- Make sure that you've written `testing` or `testing-proposed-updates` into your target distribution;

- Make sure that you've built and tested your package in `testing`, not in `unstable`;

- Make sure that your version number is higher than the version in `testing` and `testing-proposed-updates`, and lower than in `unstable`;

- After uploading and successful build on all platforms, contact the release team at &email-debian-release; and ask them to approve your upload.

### Frequently asked questions

#### What are release-critical bugs, and how do they get counted?

All bugs of some higher severities are by default considered release-critical; currently, these are `critical`, `grave` and `serious` bugs.

Such bugs are presumed to have an impact on the chances that the package will be released with the `stable` release of Debian: in general, if a package has open release-critical bugs filed on it, it won't get into `testing`, and consequently won't be released in `stable`.

The `unstable` bug count are all release-critical bugs which are marked to apply to `package`/`version` combinations that are available in unstable for a release architecture. The `testing` bug count is defined analogously.

#### How could installing a package into `testing` possibly break other packages?

The structure of the distribution archives is such that they can only contain one version of a package; a package is defined by its name. So when the source package `acmefoo` is installed into `testing`, along with its binary packages `acme-foo-bin`, `acme-bar-bin`, `libacme-foo1` and `libacme-foo-dev`, the old version is removed.

However, the old version may have provided a binary package with an old soname of a library, such as `libacme-foo0`. Removing the old `acmefoo` will remove `libacme-foo0`, which will break any packages which depend on it.

Evidently, this mainly affects packages which provide changing sets of binary packages in different versions (in turn, mainly libraries). However, it will also affect packages upon which versioned dependencies have been declared of the ==, <=, or << varieties.

When the set of binary packages provided by a source package change in this way, all the packages that depended on the old binaries will have to be updated to depend on the new binaries instead. Because installing such a source package into `testing` breaks all the packages that depended on it in `testing`, some care has to be taken now: all the depending packages must be updated and ready to be installed themselves so that they won't be broken, and, once everything is ready, manual intervention by the release manager or an assistant is normally required.

If you are having problems with complicated groups of packages like this, contact &email-debian-devel; or &email-debian-release; for help.