-<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>To Fork or Not To Fork</title><meta name="generator" content="DocBook XSL Stylesheets V1.78.1"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="article"><div class="titlepage"><div><div><h2 class="title"><a name="paper-11194"></a>To Fork or Not To Fork</h2></div><div><h3 class="subtitle"><i>Lessons From Ubuntu and Debian</i></h3></div><div><div class="author"><h3 class="author"><span class="firstname">Benjamin</span> <span class="othername">Mako</span> <span class="surname">Hill</span></h3><div class="affiliation"><span class="orgname">Canonical Limited<br></span></div><div class="affiliation"><span class="orgname">The Debian GNU/Linux Project<br></span></div><div class="affiliation"><span class="orgname">Software in the Public Interest, Inc.<br></span></div></div></div><div><p class="copyright">Copyright © 2005 Benjamin Mako Hill</p></div><div><div class="legalnotice"><a name="idp27154528"></a><p>This material is licensed under the <a class="ulink" href="http://creativecommons.org/licenses/by-sa/2.0/" target="_top">Creative
- Commons Attribution-Sharealike 2.0 License</a>.</p><p>The canonical location for the most recent version of this
- document is <a class="ulink" href="http://mako.cc/" target="_top">at the author's
- website</a>.</p></div></div><div><div class="revhistory"><table style="border-style:solid; width:100%;" summary="Revision History"><tr><th align="left" valign="top" colspan="2"><b>Revision History</b></th></tr><tr><td align="left">Revision 0.2</td><td align="left">August 7, 2005</td></tr><tr><td align="left" colspan="2">Correction and improvements.</td></tr><tr><td align="left">Revision 0.1</td><td align="left">May 15, 2005</td></tr><tr><td align="left" colspan="2">
- <p>The first version of this paper was written to an
- accepted talk given at Linuxtag 2005 given in Karlsruhe,
- Germany.</p>
- </td></tr></table></div></div></div><hr></div><div class="toc"><p><b>Table of Contents</b></p><dl class="toc"><dt><span class="section"><a href="#idp27161152">Introduction</a></span></dt><dt><span class="section"><a href="#idp27077936">"Fork" Is A Four Letter Word</a></span></dt><dt><span class="section"><a href="#idp27089792">Case Study</a></span></dt><dd><dl><dt><span class="section"><a href="#idp26985776">The Debian Project</a></span></dt><dt><span class="section"><a href="#idp26996864">Ubuntu</a></span></dt><dt><span class="section"><a href="#idp32030512">Applicability</a></span></dt></dl></dd><dt><span class="section"><a href="#idp26879744">Balancing Forking With Collaboration</a></span></dt><dd><dl><dt><span class="section"><a href="#idp26880432">Derivation and Problem Analysis</a></span></dt><dt><span class="section"><a href="#idp32061728">Distributed Source Control</a></span></dt><dt><span class="section"><a href="#idp32075664">Problem Specific Tools</a></span></dt><dt><span class="section"><a href="#idp32079568">Social Solutions</a></span></dt></dl></dd><dt><span class="section"><a href="#idp32092080">Conclusions</a></span></dt></dl></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp27161152"></a>Introduction</h2></div></div></div><p>The explosive growth of free and open source software over
- the last decade has been mirrored by an equally explosive growth
- in the ambitiousness of free software projects in choosing and
- tackling problems. The free software movement approaches these
- large problems with more code and with more expansive
- communities than was thinkable a decade ago. Example of these
- massive projects include desktop environments — like GNOME
- and KDE — and distributions like Debian, RedHat, and
- Gentoo.</p><p>These projects are leveraging the work of thousands of
- programmers — both volunteer and paid — and are
- producing millions of lines of code. Their software is being
- used by millions of users with diverse sets of needs. This
- paper focuses on two major effects of this situation:</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>The communities that free software projects — and
- in particular large projects — serve are increasingly
- diverse. It is becoming increasingly difficult for a single
- large project to release any single product that can cater
- to all of its potential users.</p></li><li class="listitem"><p>It's becoming increasingly difficult to reproduce these
- large projects. While reproducing entire project is
- impossible for small groups of hackers, it is often not even
- possible for small groups to even track and maintain a fork
- of a large project over time.</p></li></ul></div><p>Taken together, these facts imply an increasingly realized
- free software community in which programmers frequently derive
- but where traditional forking is often untenable. "Forks," as
- they are traditionally defined, must be improved upon.
- Communities around large free software projects must be smarter
- about the process of derivation than they have been in the
- past.</p><p>We are already seeing this with GNU/Linux distributions. New
- distributions are rarely built from scratch today. Instead, they
- adapted from and built on top of the work of existing projects.
- As projects and user-bases grow, these derived distributions are
- increasingly common. Most of what I describe in this essay are
- tools and experiences of derived distributions.</p><p>Software makers must pursue the idea of an
- <span class="emphasis"><em>ecosystem</em></span> of free software projects and
- products that have forked but that maintain a close relationship
- as they develop parallelly and symbiotically. To do this,
- developers should:</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>Break down the process of derivation into a set of
- different types of customization and derivation and
- prioritize methods of derivation.</p></li><li class="listitem"><p>Create and foster social solutions to the social aspects
- of the derivation problem.</p></li><li class="listitem"><p>Build and use new tools specifically designed to
- coordinate development of software in the context of an
- ecosystem of projects.</p></li><li class="listitem"><p>Distribute and utilize distributed version control tools
- with an emphasis on maintaining differences over
- time.</p></li></ul></div><p>This paper is an early analysis of this set of problems. As
- such, it is highly focused on the experience of the Ubuntu
- project and its existence as a derived Debian distribution. It
- also pulls from my experience with Debian-NP and the Custom
- Debian Distribution (CDD) community. Since I participate in both
- the Ubuntu and CDD projects, these are areas that I can discuss
- with some degree of knowledge and experience.</p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp27077936"></a>"Fork" Is A Four Letter Word</h2></div></div></div><p>The act of taking the code for a free software project and
- bifurcating it to create a new project is called "forking."
- There have been a number of famous forks in free software
- history. One of the most famous was the schism that led to the
- parallel development of two versions of the Emacs text editor:
- GNU Emacs and XEmacs. This schism persists to this day.</p><p>Some forks, like Emacs and XEmacs, are permanent. Others are
- relatively short lived. An example of this is the GCC project
- which saw two forks — EGCS and PGCC — that both
- eventually merged back into GCC. Forking can happen for any
- number of reasons. Often developers on a project develop
- political or personal differences that keep them from continuing
- to work together. In some cases, maintainers become unresponsive
- and other developers fork to keep the software alive.</p><p>Ultimately though, most forks occur because people do not
- agree on the features, the mechanisms, or the technology at the
- core of a project. People have different goals, different
- problems, and want different tools. Often, these goals, problems
- and tools are similar up until a certain point before the need
- to part ways becomes essential.</p><p>A fork occurs on the level of code but a fork is not merely
- — or even primarily — technical. Many projects create
- "branches." Branches are alternative versions of a piece of
- software used to experiment with intrusive or unstable features
- and fixes. Forks are distinguished from branches both in
- that they are often more significant departures from a technical
- perspective (i.e., more lines of code have been changed and/or
- the changes are more invasive or represent a more fundamental
- rethinking of the problem) and in that they are bifurcations
- defined in social and political terms. Branches involve a
- <span class="emphasis"><em>single</em></span> developer or community of developers
- — even if it does boil down to distinct subgroups within a
- community — whereas forks are separate projects.</p><p>Forking has historically been viewed as a bad thing in free
- software communities: they are seen to stem from people's
- inability to work together and have ended in reproduction of
- work. When I published the first version of the <a class="ulink" href="http://mako.cc/projects/howto/" target="_top">Free Software Project
- Management HOWTO</a> more than four years ago, I included
- a small subsection on forking which described the concept to
- future free software project leaders with this text:</p><div class="blockquote"><blockquote class="blockquote"><p>The short version of the fork section is, don't do them.
- Forks force developers to choose one project to work with,
- cause nasty political divisions, and redundancy of
- work.</p></blockquote></div><p>In the <span class="emphasis"><em>best</em></span> situations, a fork means
- that two groups of people need to go on developing features and
- doing work they would ordinarily do <span class="emphasis"><em>in addition
- to</em></span> tracking the forked project and having to
- hand-select and apply features and fixes to their own code-base.
- This level of monitoring and constant comparison can be
- extremely difficult and time-consuming. The situation is not
- helped substantially by traditional source control tools like
- diff, patch, CVS and Subversion which are not optimized for this
- task. The worse (and much more common) situation occurs when two
- groups go about their work ignorant or partially ignorant of the
- code being cut on the other side of the fork. Important features
- and fixes are implemented twice — differently and
- incompatibly.</p><p>The most substantial bright side to these drawbacks is that
- the problems associated with forking are so severe and notorious
- that, in most cases, the threat of a fork is enough to force
- maintainers to work out solutions that keep the fork from
- happening in the first place.</p><p>Finally, it is worth pointing out that fork is something of
- a contested term. Because definitions of forks involve, to one
- degree or another, statements about the political, organization,
- and technical distinctions between projects, bifurcations that
- many people call branches or parallel trees are described by
- others as forks. Recently, fueled by the advent of distributed
- version control systems, the definition of what is and is not a
- fork has become increasingly unclear. In part due to the same
- systems, the benefits and drawbacks of what is increasingly
- problematically called forking is equally debatable.</p></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp27089792"></a>Case Study</h2></div></div></div><p>In my introduction, I described how the growing scope of
- free software projects and the rapidly increasingly size and
- diversity of user communities is spearheading the need for new
- type of derivation that avoids, as best as possible, the
- drawbacks of forking. Nowhere is this more evident than in the
- largest projects with the broadest scope: a small group of
- projects that includes operating system distributions.</p><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp26985776"></a>The Debian Project</h3></div></div></div><p>The Debian project is by many counts the largest free
- software distribution in terms of code. It is the also,
- arguably, the largest free software project in terms of the
- number of volunteers. Debian includes more than 15,000
- packages and the work of well over 1,000 official volunteers
- and many more contributors without official membership.
- Projects without Debian's massive volunteer base cannot
- replicate what Debian has accomplished; they can rarely hope
- to even maintain what Debian has produced.</p><p>At the time that this paper was written, Distrowatch lists
- 129 distributions based on Debian<a href="#ftn.idp26988128" class="footnote" name="idp26988128"><sup class="footnote">[1]</sup></a> — most of them
- are currently active to varying degrees. Each distribution
- represents at least one person — and in most cases a
- community of people — who disagreed with Debian's vision
- or direction strongly enough to want to create a new
- distribution <span class="emphasis"><em>and</em></span> who had the technical
- capacity to follow through with this goal. Despite Debian's
- long-standing slogan — "the universal operating system"
- — the fact
- that the Debian project has become the fastest growing
- operating system while spawning so many derivatives is
- testament to the fact that, as far as software is concerned,
- one size <span class="emphasis"><em>can not</em></span> fit all.<a href="#ftn.idp26990736" class="footnote" name="idp26990736"><sup class="footnote">[2]</sup></a>
- </p><p>Organizationally, Debian derivers are located both inside
- and outside of the Debian project. A group of derivers working
- within the Debian project has labeled themselves "Custom
- Debian Distributions" and has created nearly a dozen projects
- customizing and deriving from Debian for specific groups of
- users including non-profit organization, the medical
- community, lawyers, children and many others.<a href="#ftn.idp26993168" class="footnote" name="idp26993168"><sup class="footnote">[3]</sup></a> These projects build on the core Debian distribution and
- the canonical archive from <span class="emphasis"><em>within</em></span> the
- organizational and political limits of the Debian project and
- constantly seek to minimize the delta by focusing on less
- invasive changes and by advancing creative ways of building
- the <span class="emphasis"><em>ability</em></span> to alter the core
- Debian code base through established and policy compliant
- procedures.</p><p>A second group of Debian customizers includes those
- working outside of the Debian project organizationally.
- Notable among this list are (in alphabetical order) Knoppix,
- Libranet, Linspire (formerly Lindows), Progeny, MEPIS, Ubuntu,
- Userlinux, and Xandros. With its strong technological base,
- excellent package management, wide selection of packages to
- choose from, and strong commitment to software freedom which
- ensures derivability, Debian provides an ideal point from
- which to create a GNU/Linux distribution.</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp26996864"></a>Ubuntu</h3></div></div></div><p>The Ubuntu project was started by Mark Shuttleworth in
- April 2004 and the first version was built almost entirely
- by a small group of a Debian developers employed by Shuttleworth's
- company Canonical Limited.<a href="#ftn.idp26998016" class="footnote" name="idp26998016"><sup class="footnote">[4]</sup></a> It was released to the world in late 2004.
- The second version was released six months later in April
- 2005. The goals of Ubuntu are to provide a distribution based
- on a subset of Debian with:</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>Regular and predictable releases — every six months
- with support for eighteen months.</p></li><li class="listitem"><p>An emphasis on free software that will maintain the
- derivability of the distribution.</p></li><li class="listitem"><p>An emphasis on usability and a consistent desktop
- vision. As an example, this has translated into less
- questions in the installer and a default selection and
- configuration of packages that is usable for most desktop
- users "out of the box."</p></li></ul></div><p>The Ubuntu project provides an interesting example of a
- project that aims to derive from Debian to an extensive
- degree. Ubuntu made code-level changes to nearly 1300 packages
- in Debian at the time that this paper was written and the
- speed of changes will not decelerate with time; the total
- number of changes and the total size of the delta will
- grow.<a href="#ftn.idp27004416" class="footnote" name="idp27004416"><sup class="footnote">[5]</sup></a> The changes that Ubuntu makes are primarily of the
- most intrusive kind — changes to the code itself.</p><p>That said, the Ubuntu project is explicit about the fact
- that it could not exist without the work done by the Debian
- project.<a href="#ftn.idp27006336" class="footnote" name="idp27006336"><sup class="footnote">[6]</sup></a> More importantly, Ubuntu explains that it cannot
- continue to provide the complete set of packages that its
- users depend on without the ongoing work by the Debian
- project. Even though Ubuntu has made changes to the nearly
- 1300 packages, this is less than ten percent of the total
- packages shipped in Ubuntu and pulled from Debian.</p><p>Scott James Remnant, a prominent Debian developer and a
- hacker on Ubuntu who works for Canonical Ltd., described the
- situation this way on his web log to introduce the Ubuntu
- development methodology in the week after the first public
- announcement of Canonical and Ubuntu:<a href="#ftn.idp27008624" class="footnote" name="idp27008624"><sup class="footnote">[7]</sup></a>
- </p><div class="blockquote"><blockquote class="blockquote"><p>I don't think Ubuntu is a "fork" of Debian, at least not
- in the traditional sense. A fork suggests that at some
- point we go our separate way from Debian and then
- occasionally merge in changes as we carry on down our own
- path.</p><p>Our model is quite different; every six months we take a
- snapshot of Debian's unstable distribution, apply any
- outstanding patches from our last release to it and spend a
- couple of months testing and bug-fixing it.</p><p>
- <span class="inlinemediaobject"><img src="tfontf-picture-01.png"></span>
- </p><p>One thing that should be obvious from this is that our
- job is a lot easier if Debian takes all of our changes. The
- model actually encourages us to give back to
- Debian.</p><p>That's why from the very first day we started fixing
- bugs we began sending <a class="ulink" href="http://www.no-name-yet.com/patches/" target="_top">the
- patches</a> back to Debian through the BTS. Not only
- will it make our job so much easier when we come to freeze
- for "hoary", our next release, but it's exactly what every
- derivative should do in the first place.</p></blockquote></div><p>There is some debate on the degree to which Ubuntu
- developers have succeeded in accomplishing the goals laid out
- by Remnant. Ubuntu has filed hundreds of patches in the bug
- tracking system but it has also run into problems in deciding
- <span class="emphasis"><em>what</em></span> constitutes something that should be
- fed back to Debian. Many changes are simply not relevant to
- Debian developers. For example, they may include changes to a
- package in response to another change made in another package
- in Ubuntu that will not or has not been taken by Debian. In
- many other cases, the best action in regards to a particular
- change, a particular package, and a particular upstream Debian
- developer is simply unclear.</p><p>The Ubuntu project's track record in working
- constructively with Debian is, at the moment, a mixed one.
- While an increasingly large number of Debian developers are
- maintaining their packages actively within both projects, many
- in both Debian and Ubuntu feel that Ubuntu has work left to do
- in living up to its own goal of a completely smooth productive
- relationship with Debian.</p><p>That said, the importance of the goals described by
- Remnant in the context of of the Ubuntu development model
- cannot be overstated. Every line of delta between Debian and
- Ubuntu has a cost for Ubuntu developers. Technology, social
- practices, and wise choices may reduce that cost but it cannot
- eliminate it. The resources that Ubuntu can bring to bear upon
- the problem of building a distribution are limited — far
- more limited than Debian's. As a result, there is a limit to
- how far Ubuntu can diverge; it is always in Ubuntu's advantage
- to minimize the delta where possible.</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp32030512"></a>Applicability</h3></div></div></div><p>Ubuntu and Debian are distributions and — as such
- — operate on a different scale than the vast majority of
- free software projects. They include more code and more
- people. As a result, there are questions as to whether the
- experiences and lessons learned from these projects are
- particularly applicable to the experience of smaller free
- software projects.</p><p>Clearly, because of the difficulties associated with
- forking massive amount of code and the problems associated
- with duplicating the work of large volunteer bases,
- distributions are forced into finding a way to balance the
- benefits and drawbacks of forking. However, while the need is
- stronger and more immediate in larger projects, the benefits
- of their solutions will often be fully transferable.</p><p>Clearly, modifiability of free software to better fit the
- needs of its users lies at the heart of the free software
- movement's success. However, while modification usually comes
- in the form of collaboration on a single code-base, this is
- a function of limitations in software development methodologies
- and tools rather than the best response to the needs or
- desires of users or developers.</p><p>I believe that the fundamental advantage of free software
- in the next decade will be in the growing ability of any
- single free software project to be multiple things to multiple
- users simultaneously. This will translate into the fact that,
- in the next ten years, technology and social processes will
- evolve, so that forking is increasingly less of a bad thing.
- Free software development methodology will become less
- dependent on a single project and begin to emphasize parallel
- development within an ecosystem of related projects. The
- result is that free software projects will gain a competitive
- advantage over propriety software projects through their
- ability to better serve the increasingly diverse needs of
- increasingly large and increasingly diverse user-bases.
- Although it sounds paradoxical today, more projects will
- derive and less redundant code will be written.</p><p>Projects more limited in code and scope may use the tools
- and methods described in the remainder of this paper in
- different combinations, in different ways, and to different
- degrees than the examples around distributions introduced
- here. Different projects with different needs will find that
- certain solutions work better than others. Because communities
- of the size of Debian are difficult to fork in a way that is
- beneficial to any party, it is in these communities that the
- technology and development methodologies are first
- emerging. With time, these strategies and tools will find
- themselves employed productively in a wide variety of projects
- with a broad spectrum of sizes, needs, scopes and
- descriptions.</p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp26879744"></a>Balancing Forking With Collaboration</h2></div></div></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp26880432"></a>Derivation and Problem Analysis</h3></div></div></div><p>The easiest step in creating a productive derivative
- software project is to break down the problems of derivations
- into a series of different classes of modification. Certain
- types of modification are more easily done and are
- intrinsically more maintainable.</p><p>In the context of distributions, the problem of derivation
- can be broken down into the following types of changes (sorted
- roughly according to the intrusiveness inherent in solving the
- problem and the severity of the long-term maintainability
- problems that they introduce):</p><div class="orderedlist"><ol class="orderedlist" type="1"><li class="listitem"><p>Selection of individual pieces of software;</p></li><li class="listitem"><p>Changes to the way that packages are installed or run
- (e.g., in a Live CD type environment or using a different
- installer);</p></li><li class="listitem"><p>Configuration of different pieces of software;</p></li><li class="listitem"><p>Changes made to the actual software package (made on
- the level of changes to the packages code);</p></li></ol></div><p>By breaking down the problem in this way, Debian derivers
- have been able to approach derivation in ways that focus
- energy on the less intrusive problems first.</p><p>The first area that Ubuntu focused on was selecting a
- subset of packages that Ubuntu would support. Ubuntu selected
- and supports approximate 2,000 packages. These became the
- <span class="command"><strong>main</strong></span> component in Ubuntu. Other packages in
- Debian were included in a separate section of the Ubuntu
- archive called <span class="command"><strong>universe</strong></span> but were not
- guaranteed to be supported with bug or security fixes. By
- focusing on a small subset of packages, the Ubuntu team was
- able to select a maintainable subsection of the Debian archive
- that they could maintain over time.</p><p>The most simple derived distributions — often
- working within the Debian project as CDDs but also including
- projects like Userlinux — are merely lists of packages
- and do nothing outside of package selection. The installation
- of lists of packages and the maintenance of those lists over
- time can be aided through the creation of what are called
- <span class="emphasis"><em>metapackages</em></span>: empty packages with long
- lists of "dependencies."</p><p>The second item, configuration changes, is also
- relatively low-impact. Focusing on moving as many changes as
- possible into the realm of configuration changes is a
- sustainable strategy that derivers working within the Debian
- project intent on a single code-base have pursued actively.
- Their idea is that rather than forking a piece of code due to
- disagreement in how the program should work, they can leave
- the code intact but add the <span class="emphasis"><em>ability</em></span> to
- work in a different way to the software. This alternate
- functionality is made toggleable through a configuration
- change in the same manner that applications are configured
- through questions asked at install time. Since the Debian
- project has a unified package configuration framework called
- Debconf, derivers are able to configure an entire system in a
- highly centralized manner.<a href="#ftn.idp32057520" class="footnote" name="idp32057520"><sup class="footnote">[8]</sup></a> This is not unlike RedHat's Kickstart although the
- emphasis is on maintenance of those configuration changes over
- the life and evolution of the package; Kickstart is focused
- merely on installation of the package.</p><p>A third type of configuration is limited to changes in the
- environment through which a system is run or installed. One is
- example is Progeny's Anaconda-based Debian installer which
- provides an alternate installer but results in an identical
- system. Another example is the Knoppix project which is famous
- for its "Live CD" environments. While, Knoppix makes a wide
- range of invasive changes that span all items in my list
- above, other Live CD projects, including Ubuntu's "Casper"
- project, are much closer to an alternate shell through which
- the same code is run.</p><p>Because these three methods are relatively non-invasive,
- they are reasonable strategies for small teams and individuals
- working on creating a derived distribution. However, many
- desirable changes — and in the case of some derived
- distributions, <span class="emphasis"><em>most</em></span> desirable changes
- — require more invasive techniques. The final and most
- invasive type of change — changes to code — is the
- most difficult but also the most promising and powerful if it
- can be done sustainably. Changes of this type involve
- bifurcations of the code-base and will be the topic of the
- remainder of this paper.</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp32061728"></a>Distributed Source Control</h3></div></div></div><p>One promising method of maintaining deltas in forked or
- branched projects lies in distributed version control systems
- (VCS). Traditional VCS systems work in a highly centralized
- fashion. CVS, the archetypal free software VCS and the basis
- for many others, is based around the model of a single
- centralized server. Anyone who wishes to commit to a project
- must commit to the centralized repository. While CVS allows
- users to create branches, anyone with commit rights has access
- to the entire repository. The tools for branching and merging
- over time are not particularly good.</p><p>The branching model is primarily geared toward a system
- where development is bifurcated and then the branch is merged
- completely back into the main tree. Normal use of a branch
- might include creating a development branch, making a series
- of development releases while maintaining and fixing important
- bugs in the stable primary branch, and then ultimately
- replacing the stable release with the development release. The
- CVS model is <span class="emphasis"><em>not</em></span> geared toward a system
- where an arbitrary delta, or sets of deltas, are maintained
- over time.</p><p>Distributed version control aims to solve a number of
- problems introduced by CVS and alluded to above by:</p><div class="itemizedlist"><ul class="itemizedlist" style="list-style-type: disc; "><li class="listitem"><p>Allowing people to work disconnected from each other
- and to sync with each other, in whole or in part, in an
- arbitrary and ad-hoc fashion.</p></li><li class="listitem"><p>Allowing deltas to be maintained over time.</p></li></ul></div><p>Ultimately, this requires tools that are better at merging
- changes and in <span class="emphasis"><em>not</em></span> merging certain
- changes when that is the desired behavior. It also leads to tools capable
- of history-sensitive merging.</p><p>The most famous switch to a distributed VCS model from a
- centralized VCS model was the move by the Linux kernel
- development community to the proprietary distributed version
- control system BitKeeper. In his recent announcement of the
- decision to part ways with BitKeeper, Linus Torvalds
- said:</p><div class="blockquote"><blockquote class="blockquote"><p>In fact, one impact BK has had is to very fundamentally
- make us (and me in particular) change how we do things. That
- ranges from the fine-grained changeset tracking to just how
- I ended up trusting sub-maintainers with much bigger things,
- and not having to work on a patch-by-patch basis any
- more.<a href="#ftn.idp32069728" class="footnote" name="idp32069728"><sup class="footnote">[9]</sup></a>
- </p></blockquote></div><p>At the time of the switch, free distributed version
- control tools were less advanced than they are today. At the
- moment, an incomplete list of free software VCS tools includes
- GNU Arch, Bazaar, Bazaar-NG, Darcs, Monotone, SVK (based on
- Subversion), GIT (a system developed by Linus Torvalds as a
- replacement for BitKeeper) and others.</p><p>Each of these tools, at least after they reach a certain
- level of maturity, allow or will allow users to develop
- software in a distributed fashion and to, over time, compare
- their software and pull changes from others significantly more
- easily than they could otherwise. The idea of parallel
- development lies at the heart of the model. The tools for
- merging and resolving conflicts over time, and the ability to
- "cherry pick" certain patches or changes from a parallel
- developer each make this type of development significantly
- more useful than it has been in the past.</p><p>VCSs work entirely on the level of code. Due to the nature
- of the types of changes that Ubuntu project is making to
- Debian's code, Ubuntu has focused primarily on this model and
- Canonical currently funds two major distributed control
- products — the Bazaar and Bazaar-NG projects.</p><p>In many ways, employing distributed version control
- effectively is a much easier problem to solve for small, more
- traditional, free software development projects than it is for
- GNU/Linux distributions. Because the problems associated with
- maintaining parallel development of a single piece of software
- in a set of related distributed repositories is the primary
- use case for distributed version control systems, distributed
- VCS alone can be a technical solution for certain types of
- parallel development. As the tools and social processes for
- distributed VCS evolve, they will become increasingly
- important tools in the way that free software is
- developed.</p><p>Because the problems of scale associated with building an
- entire derivative distribution are more complicated than those
- associated with working with a single "upstream" project,
- distributed version control is only now being actively
- deployed in the Ubuntu project. In doing so, the project is
- focusing on integrating these into problem specific tools
- built on top of distributed version control.</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp32075664"></a>Problem Specific Tools</h3></div></div></div><p>Another technique that Canonical Ltd. is experimenting
- with is the creation of high level tools built on top of
- distributed version control tools specifically designed for
- maintaining difference between packages. Because packages are
- usually distributed as a source file with a collection of one
- or more patches, this introduces the unique possibility of
- creating a high-level VCS system based around this fact.</p><p>In the case of Ubuntu and Debian, the ideal tool creates
- one branch per patch or feature and uses heuristics to
- analyze patch files and create these branches
- intelligently. The package build system section of the total
- patch can also be kept as a separate branch. Canonical's tool,
- called the Hypothetical Changeset Tool (HCT) (although no
- longer hypothetical), is one experimental way of creating a
- very simple, very streamlined interface for dealing with a
- particular type of source that is created and distributed in a
- particular type of way with a particular type of
- change.</p><p>While HCT promises to be very useful for people making
- derived distributions based on Debian, its application outside
- distribution makers will, in all likelihood, be limited. That
- said, it provides an example of the way that problem and
- context specific tools may play an essential role in the
- maintenance of derived code more generally.</p></div><div class="section"><div class="titlepage"><div><div><h3 class="title"><a name="idp32079568"></a>Social Solutions</h3></div></div></div><p>It has been said that it is a common folly of a
- technophile to attempt to employ technical solutions toward
- solving social problems. The problem of deriving software is
- both a technical <span class="emphasis"><em>and</em></span> social problem and
- adequately addressing the larger problems requires approaches that
- take into consideration both types of solution.</p><p>Scott James Remnant compares the relationship between
- distributions and derived distributions as similar to the
- relationship between distributions and upstream
- maintainers:</p><div class="blockquote"><blockquote class="blockquote"><p>I don't think this is much different from how Debian
- maintainers interact with their upstreams. As Debian
- maintainers we take and package upstream software and then
- act as a gateway for bugs and problems. Quite often we fix
- bugs ourselves and apply the patch to the package and send
- it upstream. Sometimes the upstream don't incorporate that
- patch and we have to make sure we don't accidentally drop it
- each subsequent release, we much prefer it if they take
- them, but we don't get angry if they don't.</p><p>This is how I see the relationship between Ubuntu and
- Debian, we're no more a fork of Debian than a Debian package
- is a fork of its upstream.</p></blockquote></div><p>Scott alludes the fact that, at least in the world of
- distributions, parallel development is already one way to view
- the <span class="emphasis"><em>modus operandi</em></span> of existing GNU/Linux
- distributions. The relationship between a deriver and derivee
- on the distribution level mirrors the relationship between the
- distribution and the "upstream" authors of the packages that
- make up the distribution. These relationships are rarely based
- around technological tools but are entirely in the realm of
- social solutions.</p><p>Ubuntu has pursued a number of different initiatives along
- these lines. The first of these has been to regularly file
- bugs in the Debian bug tracking system when bugs that exist in
- Debian are fixed in Ubuntu. While this can be partially
- automated, the choice to automate this and the manner in which
- it it is set up is a purely social one.</p><p>However, as I alluded to above, Ubuntu is still left with
- questions in regards to changes that are made to packages that
- do not necessarily fix bugs or that fix bugs that do not exist
- in Debian but may in the future. Some Debian developers want
- to hear about the full extent of changes made to their
- software in Ubuntu while others do not want to be
- bothered. Ubuntu should continue to work with Debian to find
- ways to allow developers to stay in sync.</p><p>There are also several initiatives by developers in
- Debian, Ubuntu, and in other derivations to create a
- stronger relationship between the Debian project and its
- ecosystem of derivers and between Ubuntu and Debian in
- particular. While the form that this will ultimately take is
- unclear, projects existing within an ecosystem should explore
- the realm of appropriate social relationships that will ensure
- that they can work together and be informed of each others'
- work without resorting to "spamming" each other with
- irrelevant or unnecessary information.</p><p>Another issue that has recently played an important role
- in the Debian/Ubuntu relationship is the importance of both
- giving adequate credit to the authors or upstream maintainers
- of software without implying a closer relationship than is the
- case. Derivers must walk a file line where they credit others'
- work on a project without implying that the others work for,
- support, or are connected to the derivers project to which, for
- any number of reasons, the "upstream" author might not want to
- be associated.</p><p>In the case of Debian and Ubuntu, this has resulted in an
- emphasis on keeping or importing changelog entries when
- changes are imported and in noting the pedigree of changes
- more generally. It has recently also been discussed in terms
- of the "maintainer" field in each package in Ubuntu. Ubuntu
- wants to avoid making changes to every unmodified source
- package (and introducing an unnecessary delta) but does not
- want to give the impression that the maintainer of the package
- is someone unassociated with Ubuntu. While no solution has
- been decided at the time of writing, one idea involved marking
- the maintainer of the package explicitly as a Debian
- maintainer at the time that the binary packages are built on
- the Ubuntu build machines.</p><p>The emphasis on social solutions is also essential when
- using distributed VCS technology. As Linus Torvalds alluded to
- in the quote above, the importance of technological changes to
- distributed VCS technology is only felt when people begin to
- work in a different way — when they begin to employ
- different social models of developer interaction.</p><p>While Ubuntu's experience can provide a good model for
- tackling some of these source control issues, it can only
- serve as a model and not as a fixed answer. Social solutions
- must be appropriate for a given social relationship. Even in
- situations where a package is branched because of social
- disagreements, a certain level of collaboration on a social
- level will be essential to the long term viability of the
- derivative.</p></div></div><div class="section"><div class="titlepage"><div><div><h2 class="title" style="clear: both"><a name="idp32092080"></a>Conclusions</h2></div></div></div><p>As the techniques described in this paper evolve, the role
- that they play in free software development becomes increasingly
- prominent and increasingly important. Joining them will be other
- techniques and models that I have not described and cannot
- predict. Because of the size and usefulness of their code and
- the size of their development communities, large projects like
- Debian and Ubuntu have been forced into confronting and
- attempting to mediate the problems inherent in forking and
- deriving. However, as these problems are negotiated and tools
- and processes are advanced toward solutions, free software
- projects of all sizes will be able to offer users exactly what
- they want with minimal redundancy and little duplication of
- work. In doing this, free software will harness a power that
- proprietary models cannot compete with. They will increase their
- capacity to produce better products and better processes.
- Ultimately, it will help free software capture more users, bring
- in more developers, and produce more free software of a higher
- quality.</p></div><div class="footnotes"><br><hr style="width:100; text-align:left;margin-left: 0"><div id="ftn.idp26988128" class="footnote"><p><a href="#idp26988128" class="para"><sup class="para">[1] </sup></a>Information is listed on the distrowatch homepage
- here: <a class="ulink" href="http://distrowatch.com/dwres.php?resource=independence" target="_top">http://distrowatch.com/dwres.php?resource=independence</a></p></div><div id="ftn.idp26990736" class="footnote"><p><a href="#idp26990736" class="para"><sup class="para">[2] </sup></a>Netcraft posts yearly updates on the speed at which
- Linux distributions are growing. The one in question can be
- found at: <a class="ulink" href="http://news.netcraft.com/archives/2004/01/28/debian_fastest_growing_linux_distribution.html" target="_top">http://news.netcraft.com/archives/2004/01/28/debian_fastest_growing_linux_distribution.html</a></p></div><div id="ftn.idp26993168" class="footnote"><p><a href="#idp26993168" class="para"><sup class="para">[3] </sup></a>I spearheaded and help build a now mostly defunct
- derivation of Debian called Debian-Nonprofit (Debian-NP)
- geared for non-profit organizations by working within the
- Debian project.</p></div><div id="ftn.idp26998016" class="footnote"><p><a href="#idp26998016" class="para"><sup class="para">[4] </sup></a>Information Ubuntu can be found on the <a class="ulink" href="http://www.ubuntu.com" target="_top">Ubuntu homepage.</a>
- Information Canonical Limited can be found at <a class="ulink" href="http://www.canonical.com" target="_top">Canonical's
- homepage</a>.</p></div><div id="ftn.idp27004416" class="footnote"><p><a href="#idp27004416" class="para"><sup class="para">[5] </sup></a>Scott James Remnant maintains a list of these patches
- online here: <a class="ulink" href="http://people.ubuntu.com/~scott/patches/" target="_top">http://people.ubuntu.com/~scott/patches/</a></p></div><div id="ftn.idp27006336" class="footnote"><p><a href="#idp27006336" class="para"><sup class="para">[6] </sup></a>You can see that explicit statement on Ubuntu's
- website here: <a class="ulink" href="http://www.ubuntulinux.org/ubuntu/relationship/" target="_top">http://www.ubuntulinux.org/ubuntu/relationship/</a></p></div><div id="ftn.idp27008624" class="footnote"><p><a href="#idp27008624" class="para"><sup class="para">[7] </sup></a>The
- entire post can be read here: <a class="ulink" href="http://www.netsplit.com/blog/work/canonical/ubuntu_and_debian.html" target="_top">http://www.netsplit.com/blog/work/canonical/ubuntu_and_debian.html</a></p></div><div id="ftn.idp32057520" class="footnote"><p><a href="#idp32057520" class="para"><sup class="para">[8] </sup></a>More information on
- Debconf can be
- found online at: <a class="ulink" href="http://www.kitenet.net/programs/debconf/" target="_top">http://www.kitenet.net/programs/debconf/</a></p></div><div id="ftn.idp32069728" class="footnote"><p><a href="#idp32069728" class="para"><sup class="para">[9] </sup></a>The full message can be read online
- at: <a class="ulink" href="http://kerneltrap.org/mailarchive/1/message/48393/thread" target="_top">http://kerneltrap.org/mailarchive/1/message/48393/thread</a></p></div></div></div></body></html>
+<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
+<html>
+<head>
+<meta name="generator" content=
+"HTML Tidy for Linux (vers 25 March 2009), see www.w3.org">
+<meta http-equiv="Content-Type" content=
+"text/html; charset=us-ascii">
+<title>To Fork or Not To Fork</title>
+<meta name="generator" content="DocBook XSL Stylesheets V1.78.1">
+</head>
+<body bgcolor="white" text="black" link="#0000FF" vlink="#840084"
+alink="#0000FF">
+<div class="article">
+<div class="titlepage">
+<div>
+<div>
+<h2 class="title"><a name="paper-11194" id="paper-11194"></a>To
+Fork or Not To Fork</h2>
+</div>
+<div>
+<h3 class="subtitle"><i>Lessons From Ubuntu and Debian</i></h3>
+</div>
+<div>
+<div class="author">
+<h3 class="author"><span class="firstname">Benjamin</span>
+<span class="othername">Mako</span> <span class=
+"surname">Hill</span></h3>
+<div class="affiliation"><span class="orgname">Canonical
+Limited<br></span></div>
+<div class="affiliation"><span class="orgname">The Debian GNU/Linux
+Project<br></span></div>
+<div class="affiliation"><span class="orgname">Software in the
+Public Interest, Inc.<br></span></div>
+</div>
+</div>
+<div>
+<p class="copyright">Copyright © 2005 Benjamin Mako
+Hill</p>
+</div>
+<div>
+<div class="legalnotice"><a name="idp27154528" id=
+"idp27154528"></a>
+<p>This material is licensed under the <a class="ulink" href=
+"http://creativecommons.org/licenses/by-sa/2.0/" target=
+"_top">Creative Commons Attribution-Sharealike 2.0 License</a>.</p>
+<p>The canonical location for the most recent version of this
+document is <a class="ulink" href="http://mako.cc/" target=
+"_top">at the author's website</a>.</p>
+</div>
+</div>
+<div>
+<div class="revhistory">
+<table style="border-style:solid; width:100%;" summary=
+"Revision History">
+<tr>
+<th align="left" valign="top" colspan="2"><b>Revision
+History</b></th>
+</tr>
+<tr>
+<td align="left">Revision 0.2</td>
+<td align="left">August 7, 2005</td>
+</tr>
+<tr>
+<td align="left" colspan="2">Correction and improvements.</td>
+</tr>
+<tr>
+<td align="left">Revision 0.1</td>
+<td align="left">May 15, 2005</td>
+</tr>
+<tr>
+<td align="left" colspan="2">
+<p>The first version of this paper was written to an accepted talk
+given at Linuxtag 2005 given in Karlsruhe, Germany.</p>
+</td>
+</tr>
+</table>
+</div>
+</div>
+</div>
+<hr></div>
+<div class="toc">
+<p><b>Table of Contents</b></p>
+<dl class="toc">
+<dt><span class="section"><a href=
+"#idp27161152">Introduction</a></span></dt>
+<dt><span class="section"><a href="#idp27077936">"Fork" Is A Four
+Letter Word</a></span></dt>
+<dt><span class="section"><a href="#idp27089792">Case
+Study</a></span></dt>
+<dd>
+<dl>
+<dt><span class="section"><a href="#idp26985776">The Debian
+Project</a></span></dt>
+<dt><span class="section"><a href=
+"#idp26996864">Ubuntu</a></span></dt>
+<dt><span class="section"><a href=
+"#idp32030512">Applicability</a></span></dt>
+</dl>
+</dd>
+<dt><span class="section"><a href="#idp26879744">Balancing Forking
+With Collaboration</a></span></dt>
+<dd>
+<dl>
+<dt><span class="section"><a href="#idp26880432">Derivation and
+Problem Analysis</a></span></dt>
+<dt><span class="section"><a href="#idp32061728">Distributed Source
+Control</a></span></dt>
+<dt><span class="section"><a href="#idp32075664">Problem Specific
+Tools</a></span></dt>
+<dt><span class="section"><a href="#idp32079568">Social
+Solutions</a></span></dt>
+</dl>
+</dd>
+<dt><span class="section"><a href=
+"#idp32092080">Conclusions</a></span></dt>
+</dl>
+</div>
+<div class="section">
+<div class="titlepage">
+<div>
+<div>
+<h2 class="title" style="clear: both"><a name="idp27161152" id=
+"idp27161152"></a>Introduction</h2>
+</div>
+</div>
+</div>
+<p>The explosive growth of free and open source software over the
+last decade has been mirrored by an equally explosive growth in the
+ambitiousness of free software projects in choosing and tackling
+problems. The free software movement approaches these large
+problems with more code and with more expansive communities than
+was thinkable a decade ago. Example of these massive projects
+include desktop environments — like GNOME and KDE — and
+distributions like Debian, RedHat, and Gentoo.</p>
+<p>These projects are leveraging the work of thousands of
+programmers — both volunteer and paid — and are
+producing millions of lines of code. Their software is being used
+by millions of users with diverse sets of needs. This paper focuses
+on two major effects of this situation:</p>
+<div class="itemizedlist">
+<ul class="itemizedlist" style="list-style-type: disc;">
+<li class="listitem">
+<p>The communities that free software projects — and in
+particular large projects — serve are increasingly diverse.
+It is becoming increasingly difficult for a single large project to
+release any single product that can cater to all of its potential
+users.</p>
+</li>
+<li class="listitem">
+<p>It's becoming increasingly difficult to reproduce these large
+projects. While reproducing entire project is impossible for small
+groups of hackers, it is often not even possible for small groups
+to even track and maintain a fork of a large project over time.</p>
+</li>
+</ul>
+</div>
+<p>Taken together, these facts imply an increasingly realized free
+software community in which programmers frequently derive but where
+traditional forking is often untenable. "Forks," as they are
+traditionally defined, must be improved upon. Communities around
+large free software projects must be smarter about the process of
+derivation than they have been in the past.</p>
+<p>We are already seeing this with GNU/Linux distributions. New
+distributions are rarely built from scratch today. Instead, they
+adapted from and built on top of the work of existing projects. As
+projects and user-bases grow, these derived distributions are
+increasingly common. Most of what I describe in this essay are
+tools and experiences of derived distributions.</p>
+<p>Software makers must pursue the idea of an <span class=
+"emphasis"><em>ecosystem</em></span> of free software projects and
+products that have forked but that maintain a close relationship as
+they develop parallelly and symbiotically. To do this, developers
+should:</p>
+<div class="itemizedlist">
+<ul class="itemizedlist" style="list-style-type: disc;">
+<li class="listitem">
+<p>Break down the process of derivation into a set of different
+types of customization and derivation and prioritize methods of
+derivation.</p>
+</li>
+<li class="listitem">
+<p>Create and foster social solutions to the social aspects of the
+derivation problem.</p>
+</li>
+<li class="listitem">
+<p>Build and use new tools specifically designed to coordinate
+development of software in the context of an ecosystem of
+projects.</p>
+</li>
+<li class="listitem">
+<p>Distribute and utilize distributed version control tools with an
+emphasis on maintaining differences over time.</p>
+</li>
+</ul>
+</div>
+<p>This paper is an early analysis of this set of problems. As
+such, it is highly focused on the experience of the Ubuntu project
+and its existence as a derived Debian distribution. It also pulls
+from my experience with Debian-NP and the Custom Debian
+Distribution (CDD) community. Since I participate in both the
+Ubuntu and CDD projects, these are areas that I can discuss with
+some degree of knowledge and experience.</p>
+</div>
+<div class="section">
+<div class="titlepage">
+<div>
+<div>
+<h2 class="title" style="clear: both"><a name="idp27077936" id=
+"idp27077936"></a>"Fork" Is A Four Letter Word</h2>
+</div>
+</div>
+</div>
+<p>The act of taking the code for a free software project and
+bifurcating it to create a new project is called "forking." There
+have been a number of famous forks in free software history. One of
+the most famous was the schism that led to the parallel development
+of two versions of the Emacs text editor: GNU Emacs and XEmacs.
+This schism persists to this day.</p>
+<p>Some forks, like Emacs and XEmacs, are permanent. Others are
+relatively short lived. An example of this is the GCC project which
+saw two forks — EGCS and PGCC — that both eventually
+merged back into GCC. Forking can happen for any number of reasons.
+Often developers on a project develop political or personal
+differences that keep them from continuing to work together. In
+some cases, maintainers become unresponsive and other developers
+fork to keep the software alive.</p>
+<p>Ultimately though, most forks occur because people do not agree
+on the features, the mechanisms, or the technology at the core of a
+project. People have different goals, different problems, and want
+different tools. Often, these goals, problems and tools are similar
+up until a certain point before the need to part ways becomes
+essential.</p>
+<p>A fork occurs on the level of code but a fork is not merely
+— or even primarily — technical. Many projects create
+"branches." Branches are alternative versions of a piece of
+software used to experiment with intrusive or unstable features and
+fixes. Forks are distinguished from branches both in that they are
+often more significant departures from a technical perspective
+(i.e., more lines of code have been changed and/or the changes are
+more invasive or represent a more fundamental rethinking of the
+problem) and in that they are bifurcations defined in social and
+political terms. Branches involve a <span class=
+"emphasis"><em>single</em></span> developer or community of
+developers — even if it does boil down to distinct subgroups
+within a community — whereas forks are separate projects.</p>
+<p>Forking has historically been viewed as a bad thing in free
+software communities: they are seen to stem from people's inability
+to work together and have ended in reproduction of work. When I
+published the first version of the <a class="ulink" href=
+"http://mako.cc/projects/howto/" target="_top">Free Software
+Project Management HOWTO</a> more than four years ago, I included a
+small subsection on forking which described the concept to future
+free software project leaders with this text:</p>
+<div class="blockquote">
+<blockquote class="blockquote">
+<p>The short version of the fork section is, don't do them. Forks
+force developers to choose one project to work with, cause nasty
+political divisions, and redundancy of work.</p>
+</blockquote>
+</div>
+<p>In the <span class="emphasis"><em>best</em></span> situations, a
+fork means that two groups of people need to go on developing
+features and doing work they would ordinarily do <span class=
+"emphasis"><em>in addition to</em></span> tracking the forked
+project and having to hand-select and apply features and fixes to
+their own code-base. This level of monitoring and constant
+comparison can be extremely difficult and time-consuming. The
+situation is not helped substantially by traditional source control
+tools like diff, patch, CVS and Subversion which are not optimized
+for this task. The worse (and much more common) situation occurs
+when two groups go about their work ignorant or partially ignorant
+of the code being cut on the other side of the fork. Important
+features and fixes are implemented twice — differently and
+incompatibly.</p>
+<p>The most substantial bright side to these drawbacks is that the
+problems associated with forking are so severe and notorious that,
+in most cases, the threat of a fork is enough to force maintainers
+to work out solutions that keep the fork from happening in the
+first place.</p>
+<p>Finally, it is worth pointing out that fork is something of a
+contested term. Because definitions of forks involve, to one degree
+or another, statements about the political, organization, and
+technical distinctions between projects, bifurcations that many
+people call branches or parallel trees are described by others as
+forks. Recently, fueled by the advent of distributed version
+control systems, the definition of what is and is not a fork has
+become increasingly unclear. In part due to the same systems, the
+benefits and drawbacks of what is increasingly problematically
+called forking is equally debatable.</p>
+</div>
+<div class="section">
+<div class="titlepage">
+<div>
+<div>
+<h2 class="title" style="clear: both"><a name="idp27089792" id=
+"idp27089792"></a>Case Study</h2>
+</div>
+</div>
+</div>
+<p>In my introduction, I described how the growing scope of free
+software projects and the rapidly increasingly size and diversity
+of user communities is spearheading the need for new type of
+derivation that avoids, as best as possible, the drawbacks of
+forking. Nowhere is this more evident than in the largest projects
+with the broadest scope: a small group of projects that includes
+operating system distributions.</p>
+<div class="section">
+<div class="titlepage">
+<div>
+<div>
+<h3 class="title"><a name="idp26985776" id="idp26985776"></a>The
+Debian Project</h3>
+</div>
+</div>
+</div>
+<p>The Debian project is by many counts the largest free software
+distribution in terms of code. It is the also, arguably, the
+largest free software project in terms of the number of volunteers.
+Debian includes more than 15,000 packages and the work of well over
+1,000 official volunteers and many more contributors without
+official membership. Projects without Debian's massive volunteer
+base cannot replicate what Debian has accomplished; they can rarely
+hope to even maintain what Debian has produced.</p>
+<p>At the time that this paper was written, Distrowatch lists 129
+distributions based on Debian<a href="#ftn.idp26988128" class=
+"footnote" name="idp26988128" id="idp26988128"><sup class=
+"footnote">[1]</sup></a> — most of them are currently active
+to varying degrees. Each distribution represents at least one
+person — and in most cases a community of people — who
+disagreed with Debian's vision or direction strongly enough to want
+to create a new distribution <span class=
+"emphasis"><em>and</em></span> who had the technical capacity to
+follow through with this goal. Despite Debian's long-standing
+slogan — "the universal operating system" — the fact
+that the Debian project has become the fastest growing operating
+system while spawning so many derivatives is testament to the fact
+that, as far as software is concerned, one size <span class=
+"emphasis"><em>can not</em></span> fit all.<a href=
+"#ftn.idp26990736" class="footnote" name="idp26990736" id=
+"idp26990736"><sup class="footnote">[2]</sup></a></p>
+<p>Organizationally, Debian derivers are located both inside and
+outside of the Debian project. A group of derivers working within
+the Debian project has labeled themselves "Custom Debian
+Distributions" and has created nearly a dozen projects customizing
+and deriving from Debian for specific groups of users including
+non-profit organization, the medical community, lawyers, children
+and many others.<a href="#ftn.idp26993168" class="footnote" name=
+"idp26993168" id="idp26993168"><sup class="footnote">[3]</sup></a>
+These projects build on the core Debian distribution and the
+canonical archive from <span class=
+"emphasis"><em>within</em></span> the organizational and political
+limits of the Debian project and constantly seek to minimize the
+delta by focusing on less invasive changes and by advancing
+creative ways of building the <span class=
+"emphasis"><em>ability</em></span> to alter the core Debian code
+base through established and policy compliant procedures.</p>
+<p>A second group of Debian customizers includes those working
+outside of the Debian project organizationally. Notable among this
+list are (in alphabetical order) Knoppix, Libranet, Linspire
+(formerly Lindows), Progeny, MEPIS, Ubuntu, Userlinux, and Xandros.
+With its strong technological base, excellent package management,
+wide selection of packages to choose from, and strong commitment to
+software freedom which ensures derivability, Debian provides an
+ideal point from which to create a GNU/Linux distribution.</p>
+</div>
+<div class="section">
+<div class="titlepage">
+<div>
+<div>
+<h3 class="title"><a name="idp26996864" id=
+"idp26996864"></a>Ubuntu</h3>
+</div>
+</div>
+</div>
+<p>The Ubuntu project was started by Mark Shuttleworth in April
+2004 and the first version was built almost entirely by a small
+group of a Debian developers employed by Shuttleworth's company
+Canonical Limited.<a href="#ftn.idp26998016" class="footnote" name=
+"idp26998016" id="idp26998016"><sup class="footnote">[4]</sup></a>
+It was released to the world in late 2004. The second version was
+released six months later in April 2005. The goals of Ubuntu are to
+provide a distribution based on a subset of Debian with:</p>
+<div class="itemizedlist">
+<ul class="itemizedlist" style="list-style-type: disc;">
+<li class="listitem">
+<p>Regular and predictable releases — every six months with
+support for eighteen months.</p>
+</li>
+<li class="listitem">
+<p>An emphasis on free software that will maintain the derivability
+of the distribution.</p>
+</li>
+<li class="listitem">
+<p>An emphasis on usability and a consistent desktop vision. As an
+example, this has translated into less questions in the installer
+and a default selection and configuration of packages that is
+usable for most desktop users "out of the box."</p>
+</li>
+</ul>
+</div>
+<p>The Ubuntu project provides an interesting example of a project
+that aims to derive from Debian to an extensive degree. Ubuntu made
+code-level changes to nearly 1300 packages in Debian at the time
+that this paper was written and the speed of changes will not
+decelerate with time; the total number of changes and the total
+size of the delta will grow.<a href="#ftn.idp27004416" class=
+"footnote" name="idp27004416" id="idp27004416"><sup class=
+"footnote">[5]</sup></a> The changes that Ubuntu makes are
+primarily of the most intrusive kind — changes to the code
+itself.</p>
+<p>That said, the Ubuntu project is explicit about the fact that it
+could not exist without the work done by the Debian
+project.<a href="#ftn.idp27006336" class="footnote" name=
+"idp27006336" id="idp27006336"><sup class="footnote">[6]</sup></a>
+More importantly, Ubuntu explains that it cannot continue to
+provide the complete set of packages that its users depend on
+without the ongoing work by the Debian project. Even though Ubuntu
+has made changes to the nearly 1300 packages, this is less than ten
+percent of the total packages shipped in Ubuntu and pulled from
+Debian.</p>
+<p>Scott James Remnant, a prominent Debian developer and a hacker
+on Ubuntu who works for Canonical Ltd., described the situation
+this way on his web log to introduce the Ubuntu development
+methodology in the week after the first public announcement of
+Canonical and Ubuntu:<a href="#ftn.idp27008624" class="footnote"
+name="idp27008624" id="idp27008624"><sup class=
+"footnote">[7]</sup></a></p>
+<div class="blockquote">
+<blockquote class="blockquote">
+<p>I don't think Ubuntu is a "fork" of Debian, at least not in the
+traditional sense. A fork suggests that at some point we go our
+separate way from Debian and then occasionally merge in changes as
+we carry on down our own path.</p>
+<p>Our model is quite different; every six months we take a
+snapshot of Debian's unstable distribution, apply any outstanding
+patches from our last release to it and spend a couple of months
+testing and bug-fixing it.</p>
+<p><span class="inlinemediaobject"><img src=
+"tfontf-picture-01.png"></span></p>
+<p>One thing that should be obvious from this is that our job is a
+lot easier if Debian takes all of our changes. The model actually
+encourages us to give back to Debian.</p>
+<p>That's why from the very first day we started fixing bugs we
+began sending <a class="ulink" href=
+"http://www.no-name-yet.com/patches/" target="_top">the patches</a>
+back to Debian through the BTS. Not only will it make our job so
+much easier when we come to freeze for "hoary", our next release,
+but it's exactly what every derivative should do in the first
+place.</p>
+</blockquote>
+</div>
+<p>There is some debate on the degree to which Ubuntu developers
+have succeeded in accomplishing the goals laid out by Remnant.
+Ubuntu has filed hundreds of patches in the bug tracking system but
+it has also run into problems in deciding <span class=
+"emphasis"><em>what</em></span> constitutes something that should
+be fed back to Debian. Many changes are simply not relevant to
+Debian developers. For example, they may include changes to a
+package in response to another change made in another package in
+Ubuntu that will not or has not been taken by Debian. In many other
+cases, the best action in regards to a particular change, a
+particular package, and a particular upstream Debian developer is
+simply unclear.</p>
+<p>The Ubuntu project's track record in working constructively with
+Debian is, at the moment, a mixed one. While an increasingly large
+number of Debian developers are maintaining their packages actively
+within both projects, many in both Debian and Ubuntu feel that
+Ubuntu has work left to do in living up to its own goal of a
+completely smooth productive relationship with Debian.</p>
+<p>That said, the importance of the goals described by Remnant in
+the context of of the Ubuntu development model cannot be
+overstated. Every line of delta between Debian and Ubuntu has a
+cost for Ubuntu developers. Technology, social practices, and wise
+choices may reduce that cost but it cannot eliminate it. The
+resources that Ubuntu can bring to bear upon the problem of
+building a distribution are limited — far more limited than
+Debian's. As a result, there is a limit to how far Ubuntu can
+diverge; it is always in Ubuntu's advantage to minimize the delta
+where possible.</p>
+</div>
+<div class="section">
+<div class="titlepage">
+<div>
+<div>
+<h3 class="title"><a name="idp32030512" id=
+"idp32030512"></a>Applicability</h3>
+</div>
+</div>
+</div>
+<p>Ubuntu and Debian are distributions and — as such —
+operate on a different scale than the vast majority of free
+software projects. They include more code and more people. As a
+result, there are questions as to whether the experiences and
+lessons learned from these projects are particularly applicable to
+the experience of smaller free software projects.</p>
+<p>Clearly, because of the difficulties associated with forking
+massive amount of code and the problems associated with duplicating
+the work of large volunteer bases, distributions are forced into
+finding a way to balance the benefits and drawbacks of forking.
+However, while the need is stronger and more immediate in larger
+projects, the benefits of their solutions will often be fully
+transferable.</p>
+<p>Clearly, modifiability of free software to better fit the needs
+of its users lies at the heart of the free software movement's
+success. However, while modification usually comes in the form of
+collaboration on a single code-base, this is a function of
+limitations in software development methodologies and tools rather
+than the best response to the needs or desires of users or
+developers.</p>
+<p>I believe that the fundamental advantage of free software in the
+next decade will be in the growing ability of any single free
+software project to be multiple things to multiple users
+simultaneously. This will translate into the fact that, in the next
+ten years, technology and social processes will evolve, so that
+forking is increasingly less of a bad thing. Free software
+development methodology will become less dependent on a single
+project and begin to emphasize parallel development within an
+ecosystem of related projects. The result is that free software
+projects will gain a competitive advantage over propriety software
+projects through their ability to better serve the increasingly
+diverse needs of increasingly large and increasingly diverse
+user-bases. Although it sounds paradoxical today, more projects
+will derive and less redundant code will be written.</p>
+<p>Projects more limited in code and scope may use the tools and
+methods described in the remainder of this paper in different
+combinations, in different ways, and to different degrees than the
+examples around distributions introduced here. Different projects
+with different needs will find that certain solutions work better
+than others. Because communities of the size of Debian are
+difficult to fork in a way that is beneficial to any party, it is
+in these communities that the technology and development
+methodologies are first emerging. With time, these strategies and
+tools will find themselves employed productively in a wide variety
+of projects with a broad spectrum of sizes, needs, scopes and
+descriptions.</p>
+</div>
+</div>
+<div class="section">
+<div class="titlepage">
+<div>
+<div>
+<h2 class="title" style="clear: both"><a name="idp26879744" id=
+"idp26879744"></a>Balancing Forking With Collaboration</h2>
+</div>
+</div>
+</div>
+<div class="section">
+<div class="titlepage">
+<div>
+<div>
+<h3 class="title"><a name="idp26880432" id=
+"idp26880432"></a>Derivation and Problem Analysis</h3>
+</div>
+</div>
+</div>
+<p>The easiest step in creating a productive derivative software
+project is to break down the problems of derivations into a series
+of different classes of modification. Certain types of modification
+are more easily done and are intrinsically more maintainable.</p>
+<p>In the context of distributions, the problem of derivation can
+be broken down into the following types of changes (sorted roughly
+according to the intrusiveness inherent in solving the problem and
+the severity of the long-term maintainability problems that they
+introduce):</p>
+<div class="orderedlist">
+<ol class="orderedlist" type="1">
+<li class="listitem">
+<p>Selection of individual pieces of software;</p>
+</li>
+<li class="listitem">
+<p>Changes to the way that packages are installed or run (e.g., in
+a Live CD type environment or using a different installer);</p>
+</li>
+<li class="listitem">
+<p>Configuration of different pieces of software;</p>
+</li>
+<li class="listitem">
+<p>Changes made to the actual software package (made on the level
+of changes to the packages code);</p>
+</li>
+</ol>
+</div>
+<p>By breaking down the problem in this way, Debian derivers have
+been able to approach derivation in ways that focus energy on the
+less intrusive problems first.</p>
+<p>The first area that Ubuntu focused on was selecting a subset of
+packages that Ubuntu would support. Ubuntu selected and supports
+approximate 2,000 packages. These became the <span class=
+"command"><strong>main</strong></span> component in Ubuntu. Other
+packages in Debian were included in a separate section of the
+Ubuntu archive called <span class=
+"command"><strong>universe</strong></span> but were not guaranteed
+to be supported with bug or security fixes. By focusing on a small
+subset of packages, the Ubuntu team was able to select a
+maintainable subsection of the Debian archive that they could
+maintain over time.</p>
+<p>The most simple derived distributions — often working
+within the Debian project as CDDs but also including projects like
+Userlinux — are merely lists of packages and do nothing
+outside of package selection. The installation of lists of packages
+and the maintenance of those lists over time can be aided through
+the creation of what are called <span class=
+"emphasis"><em>metapackages</em></span>: empty packages with long
+lists of "dependencies."</p>
+<p>The second item, configuration changes, is also relatively
+low-impact. Focusing on moving as many changes as possible into the
+realm of configuration changes is a sustainable strategy that
+derivers working within the Debian project intent on a single
+code-base have pursued actively. Their idea is that rather than
+forking a piece of code due to disagreement in how the program
+should work, they can leave the code intact but add the
+<span class="emphasis"><em>ability</em></span> to work in a
+different way to the software. This alternate functionality is made
+toggleable through a configuration change in the same manner that
+applications are configured through questions asked at install
+time. Since the Debian project has a unified package configuration
+framework called Debconf, derivers are able to configure an entire
+system in a highly centralized manner.<a href="#ftn.idp32057520"
+class="footnote" name="idp32057520" id="idp32057520"><sup class=
+"footnote">[8]</sup></a> This is not unlike RedHat's Kickstart
+although the emphasis is on maintenance of those configuration
+changes over the life and evolution of the package; Kickstart is
+focused merely on installation of the package.</p>
+<p>A third type of configuration is limited to changes in the
+environment through which a system is run or installed. One is
+example is Progeny's Anaconda-based Debian installer which provides
+an alternate installer but results in an identical system. Another
+example is the Knoppix project which is famous for its "Live CD"
+environments. While, Knoppix makes a wide range of invasive changes
+that span all items in my list above, other Live CD projects,
+including Ubuntu's "Casper" project, are much closer to an
+alternate shell through which the same code is run.</p>
+<p>Because these three methods are relatively non-invasive, they
+are reasonable strategies for small teams and individuals working
+on creating a derived distribution. However, many desirable changes
+— and in the case of some derived distributions, <span class=
+"emphasis"><em>most</em></span> desirable changes — require
+more invasive techniques. The final and most invasive type of
+change — changes to code — is the most difficult but
+also the most promising and powerful if it can be done sustainably.
+Changes of this type involve bifurcations of the code-base and will
+be the topic of the remainder of this paper.</p>
+</div>
+<div class="section">
+<div class="titlepage">
+<div>
+<div>
+<h3 class="title"><a name="idp32061728" id=
+"idp32061728"></a>Distributed Source Control</h3>
+</div>
+</div>
+</div>
+<p>One promising method of maintaining deltas in forked or branched
+projects lies in distributed version control systems (VCS).
+Traditional VCS systems work in a highly centralized fashion. CVS,
+the archetypal free software VCS and the basis for many others, is
+based around the model of a single centralized server. Anyone who
+wishes to commit to a project must commit to the centralized
+repository. While CVS allows users to create branches, anyone with
+commit rights has access to the entire repository. The tools for
+branching and merging over time are not particularly good.</p>
+<p>The branching model is primarily geared toward a system where
+development is bifurcated and then the branch is merged completely
+back into the main tree. Normal use of a branch might include
+creating a development branch, making a series of development
+releases while maintaining and fixing important bugs in the stable
+primary branch, and then ultimately replacing the stable release
+with the development release. The CVS model is <span class=
+"emphasis"><em>not</em></span> geared toward a system where an
+arbitrary delta, or sets of deltas, are maintained over time.</p>
+<p>Distributed version control aims to solve a number of problems
+introduced by CVS and alluded to above by:</p>
+<div class="itemizedlist">
+<ul class="itemizedlist" style="list-style-type: disc;">
+<li class="listitem">
+<p>Allowing people to work disconnected from each other and to sync
+with each other, in whole or in part, in an arbitrary and ad-hoc
+fashion.</p>
+</li>
+<li class="listitem">
+<p>Allowing deltas to be maintained over time.</p>
+</li>
+</ul>
+</div>
+<p>Ultimately, this requires tools that are better at merging
+changes and in <span class="emphasis"><em>not</em></span> merging
+certain changes when that is the desired behavior. It also leads to
+tools capable of history-sensitive merging.</p>
+<p>The most famous switch to a distributed VCS model from a
+centralized VCS model was the move by the Linux kernel development
+community to the proprietary distributed version control system
+BitKeeper. In his recent announcement of the decision to part ways
+with BitKeeper, Linus Torvalds said:</p>
+<div class="blockquote">
+<blockquote class="blockquote">
+<p>In fact, one impact BK has had is to very fundamentally make us
+(and me in particular) change how we do things. That ranges from
+the fine-grained changeset tracking to just how I ended up trusting
+sub-maintainers with much bigger things, and not having to work on
+a patch-by-patch basis any more.<a href="#ftn.idp32069728" class=
+"footnote" name="idp32069728" id="idp32069728"><sup class=
+"footnote">[9]</sup></a></p>
+</blockquote>
+</div>
+<p>At the time of the switch, free distributed version control
+tools were less advanced than they are today. At the moment, an
+incomplete list of free software VCS tools includes GNU Arch,
+Bazaar, Bazaar-NG, Darcs, Monotone, SVK (based on Subversion), GIT
+(a system developed by Linus Torvalds as a replacement for
+BitKeeper) and others.</p>
+<p>Each of these tools, at least after they reach a certain level
+of maturity, allow or will allow users to develop software in a
+distributed fashion and to, over time, compare their software and
+pull changes from others significantly more easily than they could
+otherwise. The idea of parallel development lies at the heart of
+the model. The tools for merging and resolving conflicts over time,
+and the ability to "cherry pick" certain patches or changes from a
+parallel developer each make this type of development significantly
+more useful than it has been in the past.</p>
+<p>VCSs work entirely on the level of code. Due to the nature of
+the types of changes that Ubuntu project is making to Debian's
+code, Ubuntu has focused primarily on this model and Canonical
+currently funds two major distributed control products — the
+Bazaar and Bazaar-NG projects.</p>
+<p>In many ways, employing distributed version control effectively
+is a much easier problem to solve for small, more traditional, free
+software development projects than it is for GNU/Linux
+distributions. Because the problems associated with maintaining
+parallel development of a single piece of software in a set of
+related distributed repositories is the primary use case for
+distributed version control systems, distributed VCS alone can be a
+technical solution for certain types of parallel development. As
+the tools and social processes for distributed VCS evolve, they
+will become increasingly important tools in the way that free
+software is developed.</p>
+<p>Because the problems of scale associated with building an entire
+derivative distribution are more complicated than those associated
+with working with a single "upstream" project, distributed version
+control is only now being actively deployed in the Ubuntu project.
+In doing so, the project is focusing on integrating these into
+problem specific tools built on top of distributed version
+control.</p>
+</div>
+<div class="section">
+<div class="titlepage">
+<div>
+<div>
+<h3 class="title"><a name="idp32075664" id=
+"idp32075664"></a>Problem Specific Tools</h3>
+</div>
+</div>
+</div>
+<p>Another technique that Canonical Ltd. is experimenting with is
+the creation of high level tools built on top of distributed
+version control tools specifically designed for maintaining
+difference between packages. Because packages are usually
+distributed as a source file with a collection of one or more
+patches, this introduces the unique possibility of creating a
+high-level VCS system based around this fact.</p>
+<p>In the case of Ubuntu and Debian, the ideal tool creates one
+branch per patch or feature and uses heuristics to analyze patch
+files and create these branches intelligently. The package build
+system section of the total patch can also be kept as a separate
+branch. Canonical's tool, called the Hypothetical Changeset Tool
+(HCT) (although no longer hypothetical), is one experimental way of
+creating a very simple, very streamlined interface for dealing with
+a particular type of source that is created and distributed in a
+particular type of way with a particular type of change.</p>
+<p>While HCT promises to be very useful for people making derived
+distributions based on Debian, its application outside distribution
+makers will, in all likelihood, be limited. That said, it provides
+an example of the way that problem and context specific tools may
+play an essential role in the maintenance of derived code more
+generally.</p>
+</div>
+<div class="section">
+<div class="titlepage">
+<div>
+<div>
+<h3 class="title"><a name="idp32079568" id="idp32079568"></a>Social
+Solutions</h3>
+</div>
+</div>
+</div>
+<p>It has been said that it is a common folly of a technophile to
+attempt to employ technical solutions toward solving social
+problems. The problem of deriving software is both a technical
+<span class="emphasis"><em>and</em></span> social problem and
+adequately addressing the larger problems requires approaches that
+take into consideration both types of solution.</p>
+<p>Scott James Remnant compares the relationship between
+distributions and derived distributions as similar to the
+relationship between distributions and upstream maintainers:</p>
+<div class="blockquote">
+<blockquote class="blockquote">
+<p>I don't think this is much different from how Debian maintainers
+interact with their upstreams. As Debian maintainers we take and
+package upstream software and then act as a gateway for bugs and
+problems. Quite often we fix bugs ourselves and apply the patch to
+the package and send it upstream. Sometimes the upstream don't
+incorporate that patch and we have to make sure we don't
+accidentally drop it each subsequent release, we much prefer it if
+they take them, but we don't get angry if they don't.</p>
+<p>This is how I see the relationship between Ubuntu and Debian,
+we're no more a fork of Debian than a Debian package is a fork of
+its upstream.</p>
+</blockquote>
+</div>
+<p>Scott alludes the fact that, at least in the world of
+distributions, parallel development is already one way to view the
+<span class="emphasis"><em>modus operandi</em></span> of existing
+GNU/Linux distributions. The relationship between a deriver and
+derivee on the distribution level mirrors the relationship between
+the distribution and the "upstream" authors of the packages that
+make up the distribution. These relationships are rarely based
+around technological tools but are entirely in the realm of social
+solutions.</p>
+<p>Ubuntu has pursued a number of different initiatives along these
+lines. The first of these has been to regularly file bugs in the
+Debian bug tracking system when bugs that exist in Debian are fixed
+in Ubuntu. While this can be partially automated, the choice to
+automate this and the manner in which it it is set up is a purely
+social one.</p>
+<p>However, as I alluded to above, Ubuntu is still left with
+questions in regards to changes that are made to packages that do
+not necessarily fix bugs or that fix bugs that do not exist in
+Debian but may in the future. Some Debian developers want to hear
+about the full extent of changes made to their software in Ubuntu
+while others do not want to be bothered. Ubuntu should continue to
+work with Debian to find ways to allow developers to stay in
+sync.</p>
+<p>There are also several initiatives by developers in Debian,
+Ubuntu, and in other derivations to create a stronger relationship
+between the Debian project and its ecosystem of derivers and
+between Ubuntu and Debian in particular. While the form that this
+will ultimately take is unclear, projects existing within an
+ecosystem should explore the realm of appropriate social
+relationships that will ensure that they can work together and be
+informed of each others' work without resorting to "spamming" each
+other with irrelevant or unnecessary information.</p>
+<p>Another issue that has recently played an important role in the
+Debian/Ubuntu relationship is the importance of both giving
+adequate credit to the authors or upstream maintainers of software
+without implying a closer relationship than is the case. Derivers
+must walk a file line where they credit others' work on a project
+without implying that the others work for, support, or are
+connected to the derivers project to which, for any number of
+reasons, the "upstream" author might not want to be associated.</p>
+<p>In the case of Debian and Ubuntu, this has resulted in an
+emphasis on keeping or importing changelog entries when changes are
+imported and in noting the pedigree of changes more generally. It
+has recently also been discussed in terms of the "maintainer" field
+in each package in Ubuntu. Ubuntu wants to avoid making changes to
+every unmodified source package (and introducing an unnecessary
+delta) but does not want to give the impression that the maintainer
+of the package is someone unassociated with Ubuntu. While no
+solution has been decided at the time of writing, one idea involved
+marking the maintainer of the package explicitly as a Debian
+maintainer at the time that the binary packages are built on the
+Ubuntu build machines.</p>
+<p>The emphasis on social solutions is also essential when using
+distributed VCS technology. As Linus Torvalds alluded to in the
+quote above, the importance of technological changes to distributed
+VCS technology is only felt when people begin to work in a
+different way — when they begin to employ different social
+models of developer interaction.</p>
+<p>While Ubuntu's experience can provide a good model for tackling
+some of these source control issues, it can only serve as a model
+and not as a fixed answer. Social solutions must be appropriate for
+a given social relationship. Even in situations where a package is
+branched because of social disagreements, a certain level of
+collaboration on a social level will be essential to the long term
+viability of the derivative.</p>
+</div>
+</div>
+<div class="section">
+<div class="titlepage">
+<div>
+<div>
+<h2 class="title" style="clear: both"><a name="idp32092080" id=
+"idp32092080"></a>Conclusions</h2>
+</div>
+</div>
+</div>
+<p>As the techniques described in this paper evolve, the role that
+they play in free software development becomes increasingly
+prominent and increasingly important. Joining them will be other
+techniques and models that I have not described and cannot predict.
+Because of the size and usefulness of their code and the size of
+their development communities, large projects like Debian and
+Ubuntu have been forced into confronting and attempting to mediate
+the problems inherent in forking and deriving. However, as these
+problems are negotiated and tools and processes are advanced toward
+solutions, free software projects of all sizes will be able to
+offer users exactly what they want with minimal redundancy and
+little duplication of work. In doing this, free software will
+harness a power that proprietary models cannot compete with. They
+will increase their capacity to produce better products and better
+processes. Ultimately, it will help free software capture more
+users, bring in more developers, and produce more free software of
+a higher quality.</p>
+</div>
+<div class="footnotes"><br>
+<hr style="width:100; text-align:left;margin-left: 0">
+<div id="ftn.idp26988128" class="footnote">
+<p><a href="#idp26988128" class="para"><sup class=
+"para">[1]</sup></a> Information is listed on the distrowatch
+homepage here: <a class="ulink" href=
+"http://distrowatch.com/dwres.php?resource=independence" target=
+"_top">http://distrowatch.com/dwres.php?resource=independence</a></p>
+</div>
+<div id="ftn.idp26990736" class="footnote">
+<p><a href="#idp26990736" class="para"><sup class=
+"para">[2]</sup></a> Netcraft posts yearly updates on the speed at
+which Linux distributions are growing. The one in question can be
+found at: <a class="ulink" href=
+"http://news.netcraft.com/archives/2004/01/28/debian_fastest_growing_linux_distribution.html"
+target=
+"_top">http://news.netcraft.com/archives/2004/01/28/debian_fastest_growing_linux_distribution.html</a></p>
+</div>
+<div id="ftn.idp26993168" class="footnote">
+<p><a href="#idp26993168" class="para"><sup class=
+"para">[3]</sup></a> I spearheaded and help build a now mostly
+defunct derivation of Debian called Debian-Nonprofit (Debian-NP)
+geared for non-profit organizations by working within the Debian
+project.</p>
+</div>
+<div id="ftn.idp26998016" class="footnote">
+<p><a href="#idp26998016" class="para"><sup class=
+"para">[4]</sup></a> Information Ubuntu can be found on the
+<a class="ulink" href="http://www.ubuntu.com" target="_top">Ubuntu
+homepage.</a> Information Canonical Limited can be found at
+<a class="ulink" href="http://www.canonical.com" target=
+"_top">Canonical's homepage</a>.</p>
+</div>
+<div id="ftn.idp27004416" class="footnote">
+<p><a href="#idp27004416" class="para"><sup class=
+"para">[5]</sup></a> Scott James Remnant maintains a list of these
+patches online here: <a class="ulink" href=
+"http://people.ubuntu.com/~scott/patches/" target=
+"_top">http://people.ubuntu.com/~scott/patches/</a></p>
+</div>
+<div id="ftn.idp27006336" class="footnote">
+<p><a href="#idp27006336" class="para"><sup class=
+"para">[6]</sup></a> You can see that explicit statement on
+Ubuntu's website here: <a class="ulink" href=
+"http://www.ubuntulinux.org/ubuntu/relationship/" target=
+"_top">http://www.ubuntulinux.org/ubuntu/relationship/</a></p>
+</div>
+<div id="ftn.idp27008624" class="footnote">
+<p><a href="#idp27008624" class="para"><sup class=
+"para">[7]</sup></a> The entire post can be read here: <a class=
+"ulink" href=
+"http://www.netsplit.com/blog/work/canonical/ubuntu_and_debian.html"
+target=
+"_top">http://www.netsplit.com/blog/work/canonical/ubuntu_and_debian.html</a></p>
+</div>
+<div id="ftn.idp32057520" class="footnote">
+<p><a href="#idp32057520" class="para"><sup class=
+"para">[8]</sup></a> More information on Debconf can be found
+online at: <a class="ulink" href=
+"http://www.kitenet.net/programs/debconf/" target=
+"_top">http://www.kitenet.net/programs/debconf/</a></p>
+</div>
+<div id="ftn.idp32069728" class="footnote">
+<p><a href="#idp32069728" class="para"><sup class=
+"para">[9]</sup></a> The full message can be read online at:
+<a class="ulink" href=
+"http://kerneltrap.org/mailarchive/1/message/48393/thread" target=
+"_top">http://kerneltrap.org/mailarchive/1/message/48393/thread</a></p>
+</div>
+</div>
+</div>
+</body>
+</html>