11 The FreeBSD Committers' Big List of Rules

11.1 Details

1. Respect other committers.

   This means that you need to treat other committers as the peer-group developers that they are. Despite our occasional attempts to prove the contrary, one does not get to be a committer by being stupid and nothing rankles more than being treated that way by one of your peers. Whether we always feel respect for one another or not (and everyone has off days), we still have to treat other committers with respect at all times, on public forums and in private email.

   Being able to work together long term is this project's greatest asset, one far more important than any set of changes to the code, and turning arguments about code into issues that affect our long-term ability to work harmoniously together is just not worth the trade-off by any conceivable stretch of the imagination.

   To comply with this rule, do not send email when you are angry or otherwise behave in a manner which is likely to strike others as needlessly confrontational. First calm down, then think about how to communicate in the most effective fashion for convincing the other person(s) that your side of the argument is correct, do not just blow off some steam so you can feel better in the short term at the cost of a long-term flame war. Not only is this very bad “energy economics”, but repeated displays of public aggression which impair our ability to work well together will be dealt with severely by the project leadership and may result in suspension or termination of your commit privileges. The project leadership will take into account both public and private communications brought before it. It will not seek the disclosure of private communications, but it will take it into account if it is volunteered by the committers involved in the complaint.

   All of this is never an option which the project's leadership enjoys in the slightest, but unity comes first. No amount of code or good advice is worth trading that away.

2. Respect other contributors.

   You were not always a committer. At one time you were a contributor. Remember that at all times. Remember what it was like trying to get help and attention. Do not forget that your work as a contributor was very important to you. Remember what it was like. Do not discourage, belittle, or demean contributors. Treat them with respect. They are our committers in waiting. They are every bit as important to the project as committers. Their contributions are as valid and as important as your own. After all, you made many contributions before you became a committer. Always remember that.

   Consider the points raised under 1 and apply them also to contributors.

3. Discuss any significant change before committing.

   The repository is not where changes should be initially submitted for correctness or argued over, that should happen first in the mailing lists and the commit should only happen once something resembling consensus has been reached. This does not mean that you have to ask permission before correcting every obvious syntax error or manual page misspelling, simply that you should try to develop a feel for when a proposed change is not quite such a no-brainer and requires some feedback first. People really do not mind sweeping changes if the result is something clearly better than what they had before, they just do not like being surprised by those changes. The very best way of making sure that you are on the right track is to have your code reviewed by one or more other committers.

   When in doubt, ask for review!

4. Respect existing maintainers if listed.

   Many parts of FreeBSD are not “owned” in the sense that any specific individual will jump up and yell if you commit a change to “their” area, but it still pays to check first. One convention we use is to put a maintainer line in the Makefile for any package or subtree which is being actively maintained by one or more people; see http://www.FreeBSD.org/doc/en_US.ISO8859-1/books/developers-handbook/policies.html for documentation on this. Where sections of code have several maintainers, commits to affected areas by one maintainer need to be reviewed by at least one other maintainer. In cases where the “maintainer-ship” of something is not clear, you can also look at the repository logs for the file(s) in question and see if someone has been working recently or predominantly in that area.

   Other areas of FreeBSD fall under the control of someone who manages an overall category of FreeBSD evolution, such as internationalization or networking. See http://www.FreeBSD.org/administration.html for more information on this.

5. Any disputed change must be backed out pending resolution of the dispute if requested by a maintainer. Security related changes may override a maintainer's wishes at the Security Officer's discretion.

   This may be hard to swallow in times of conflict (when each side is convinced that they are in the right, of course) but a version control system makes it unnecessary to have an ongoing dispute raging when it is far easier to simply reverse the disputed change, get everyone calmed down again and then try to figure out what is the best way to proceed. If the change turns out to be the best thing after all, it can be easily brought back. If it turns out not to be, then the users did not have to live with the bogus change in the tree while everyone was busily debating its merits. People very rarely call for back-outs in the repository since discussion generally exposes bad or controversial changes before the commit even happens, but on such rare occasions the back-out should be done without argument so that we can get immediately on to the topic of figuring out whether it was bogus or not.

6. Changes go to FreeBSD-CURRENT before FreeBSD-STABLE unless specifically permitted by the release engineer or unless they are not applicable to FreeBSD-CURRENT. Any non-trivial or non-urgent change which is applicable should also be allowed to sit in FreeBSD-CURRENT for at least 3 days before merging so that it can be given sufficient testing. The release engineer has the same authority over the FreeBSD-STABLE branch as outlined in rule #5.

   This is another “do not argue about it” issue since it is the release engineer who is ultimately responsible (and gets beaten up) if a change turns out to be bad. Please respect this and give the release engineer your full cooperation when it comes to the FreeBSD-STABLE branch. The management of FreeBSD-STABLE may frequently seem to be overly conservative to the casual observer, but also bear in mind the fact that conservatism is supposed to be the hallmark of FreeBSD-STABLE and different rules apply there than in FreeBSD-CURRENT. There is also really no point in having FreeBSD-CURRENT be a testing ground if changes are merged over to FreeBSD-STABLE immediately. Changes need a chance to be tested by the FreeBSD-CURRENT developers, so allow some time to elapse before merging unless the FreeBSD-STABLE fix is critical, time sensitive or so obvious as to make further testing unnecessary (spelling fixes to manual pages, obvious bug/typo fixes, etc.) In other words, apply common sense.

   Changes to the security branches (for example, RELENG_6_0) must be approved by a member of the Security Officer Team <security-officer@FreeBSD.org>, or in some cases, by a member of the Release Engineering Team <re@FreeBSD.org>.

7. Do not fight in public with other committers; it looks bad. If you must “strongly disagree” about something, do so only in private.

   This project has a public image to uphold and that image is very important to all of us, especially if we are to continue to attract new members. There will be occasions when, despite everyone's very best attempts at self-control, tempers are lost and angry words are exchanged. The best thing that can be done in such cases is to minimize the effects of this until everyone has cooled back down. That means that you should not air your angry words in public and you should not forward private correspondence to public mailing lists or aliases. What people say one-to-one is often much less sugar-coated than what they would say in public, and such communications therefore have no place there - they only serve to inflame an already bad situation. If the person sending you a flame-o-gram at least had the grace to send it privately, then have the grace to keep it private yourself. If you feel you are being unfairly treated by another developer, and it is causing you anguish, bring the matter up with core rather than taking it public. Core will do its best to play peace makers and get things back to sanity. In cases where the dispute involves a change to the codebase and the participants do not appear to be reaching an amicable agreement, core may appoint a mutually-agreeable 3rd party to resolve the dispute. All parties involved must then agree to be bound by the decision reached by this 3rd party.

8. Respect all code freezes and read the committers and developers mailing list on a timely basis so you know when a code freeze is in effect.

   Committing unapproved changes during a code freeze is a really big mistake and committers are expected to keep up-to-date on what is going on before jumping in after a long absence and committing 10 megabytes worth of accumulated stuff. People who abuse this on a regular basis will have their commit privileges suspended until they get back from the FreeBSD Happy Reeducation Camp we run in Greenland.

9. When in doubt on any procedure, ask first!

   Many mistakes are made because someone is in a hurry and just assumes they know the right way of doing something. If you have not done it before, chances are good that you do not actually know the way we do things and really need to ask first or you are going to completely embarrass yourself in public. There is no shame in asking “how in the heck do I do this?” We already know you are an intelligent person; otherwise, you would not be a committer.

10. Test your changes before committing them.

    This may sound obvious, but if it really were so obvious then we probably would not see so many cases of people clearly not doing this. If your changes are to the kernel, make sure you can still compile both GENERIC and LINT. If your changes are anywhere else, make sure you can still make world. If your changes are to a branch, make sure your testing occurs with a machine which is running that code. If you have a change which also may break another architecture, be sure and test on all supported architectures. Please refer to the FreeBSD Internal Page for a list of available resources. As other architectures are added to the FreeBSD supported platforms list, the appropriate shared testing resources will be made available.

11. Do not commit to anything under the src/contrib, src/crypto, and src/sys/contrib trees without explicit approval from the respective maintainer(s).

    The trees mentioned above are for contributed software usually imported onto a vendor branch. Committing something there, even if it does not take the file off the vendor branch, may cause unnecessary headaches for those responsible for maintaining that particular piece of software. Thus, unless you have explicit approval from the maintainer (or you are the maintainer), do not commit there!

    Please note that this does not mean you should not try to improve the software in question; you are still more than welcome to do so. Ideally, you should submit your patches to the vendor. If your changes are FreeBSD-specific, talk to the maintainer; they may be willing to apply them locally. But whatever you do, do not commit there by yourself!

    Contact the FreeBSD core team if you wish to take up maintainership of an unmaintained part of the tree.

11.2 Policy on Multiple Architectures

FreeBSD has added several new architecture ports during recent release cycles and is truly no longer an i386™ centric operating system. In an effort to make it easier to keep FreeBSD portable across the platforms we support, core has developed the following mandate:

Our 32-bit reference platform is i386, and our 64-bit reference platform is Sparc64. Major design work (including major API and ABI changes) must prove itself on at least one 32-bit and at least one 64-bit platform, preferably the primary reference platforms, before it may be committed to the source tree.

The i386 and Sparc64 platforms were chosen due to being more readily available to developers and as representatives of more diverse processor and system designs - big vs little endian, register file vs register stack, different DMA and cache implementations, hardware page tables vs software TLB management etc.

The ia64 platform has many of the same complications that Sparc64 has, but is still limited in availability to developers.

We will continue to re-evaluate this policy as cost and availability of the 64-bit platforms change.

Developers should also be aware of our Tier Policy for the long term support of hardware architectures. The rules here are intended to provide guidance during the development process, and are distinct from the requirements for features and architectures listed in that section. The Tier rules for feature support on architectures at release-time are more strict than the rules for changes during the development process.

11.3 Other Suggestions

When committing documentation changes, use a spell checker before committing. For all SGML docs, you should also verify that your formatting directives are correct by running make lint.

For all on-line manual pages, run manck (from ports) over the manual page to verify all of the cross references and file references are correct and that the man page has all of the appropriate MLINKs installed.

Do not mix style fixes with new functionality. A style fix is any change which does not modify the functionality of the code. Mixing the changes obfuscates the functionality change when asking for differences between revisions, which can hide any new bugs. Do not include whitespace changes with content changes in commits to doc/ or www/. The extra clutter in the diffs makes the translators' job much more difficult. Instead, make any style or whitespace changes in separate commits that are clearly labeled as such in the commit message.

11.4 Deprecating Features

When it is necessary to remove functionality from software in the base system the following guidelines should be followed whenever possible:

1. Mention is made in the manual page and possibly the release notes that the option, utility, or interface is deprecated. Use of the deprecated feature generates a warning.

2. The option, utility, or interface is preserved until the next major (point zero) release.

3. The option, utility, or interface is removed and no longer documented. It is now obsolete. It is also generally a good idea to note its removal in the release notes.