Distro Walk – Arch Linux

According to DistroWatch, 274 Linux distributions are active [1]. However, that number is misleading. Many distributions are heavily based on other distros, with only minor variations such as software selection or the intended audience. Many distributions, too, are dependent on a major distro's repositories. By contrast, Arch Linux, since its founding in March 2002, has gained a reputation for doing things its own way, according to a well-defined set of principles that appeals to users who prefer simplicity. Recently, I sent questions to Arch Linux Leader Levente Polyak, who consulted with the distribution's core developers to provide answers.

Arch was founded by Judd Vinet, who was lead programmer until 2007. According to the Arch team, Vinet was inspired by two distributions: CRUX [2] and PLD [3]. However, while he considered CRUX simple and elegant, Vinet considered both CRUX and PLD to be lacking decent package management. Acting on this analysis, Vinet began the pacman [4] package manager (Figure 1), which to this day is one of Arch's characteristic features.

Figure 1: The pacman package manager is one of Arch Linux's defining features.

Early on, the distribution defined itself as "simple" and "lightweight." The Arch team defines simplicity as "without unnecessary additions or modifications. It ships software as released by the original developers upstream with minimal distribution (downstream) changes. Patches not accepted upstream are avoided, and Arch's downstream patches consist almost entirely of backported bug fixes that are made obsolete by the project's next release. When we need patches in the project, most of the work ends upstream." An example of Arch's concept of simplicity is its installer (Figure 2), which makes no assumptions about what users want, but it does explain how users can do the most common tasks in its documentation.

Figure 2: Unlike most distributions' installers, Arch Linux makes few assumptions about what users want, guiding them instead.

Similarly, the Arch team says that the distribution is lightweight "in the sense that the default installation is a minimal base system, which can be configured by the user to only add what is needed." Asked what other values Arch tries to follow, the core team listed:

• Modernity: A rolling-release system that allows for one-time installation with continuous upgrades and the latest software
• Versatility – A general-purpose distribution designed for multiple uses from personal computers to servers and CI/CD deployment chains
• Security – Backported and upgraded packages with resources invested in the reproducible builds initiative as well as ensuring deterministic and verifiable package artifacts

Other goals are proposed and discussed by the entire project. Asked how well these goals are met, the team cheerfully replies, "we truthfully don't have a clue." Although Arch is widely used, the main concern is to make a distribution that its developers want to use. While the distribution does not track downloads, the fact that some one hundred thousand are registered on its forums suggests its principles are popular ones.

Organization

Arch is developed entirely by volunteers working on the mailing lists, IRC, and the bug tracker. The Arch team emphasizes that they have no corporate sponsorship or any other external pressure on development.

"We have few formal processes," the team notes. Much of the work is done by teams: Security, Reproducible Builds, Testing, and DevOps, with general decisions made by consensus. Until recently, the Arch Leader's term length was not limited; Aaron Griffin had been leader since 2007, and there was no procedure for changing positions. However, in early 2020, the project limited leaders to a term of two years, with leaders voted on by all developers, trusted users, and support staff (a total of about 105 people), who list candidates in order of preference. Voting takes place over a two-week period and is presided over by project members who are not running for office and have not nominated anyone. No quorum is required, and leaders whose term has expired can run again any number of times.

Derivative Distributions

DistroWatch lists 20 other derivative distributions (see Table 1). By comparison, Fedora has only 12, and Linux Mint three. One mark of Arch's consistent popularity is that only Debian and Ubuntu have more derivatives.

Arch's core team divides derivatives into two types: "CPU ports rebuild to their specific architecture and may add additional specific packages and patches. They either use our package tree directly and regularly report bugs for packages that don't build, which is extremely helpful. We appreciate their hard work in making Arch available to non-official architectures."

The team continues, "The other sort are the re-spins/flavors, which customize Arch for a particular goal. Sadly, we rarely hear from them and do not generally receive offers of contributions. One of the exceptions is Parabola GNU/Linux-libre, members of which have submitted a number of patches to Arch tooling or are participants in the Arch pro-audio ecosystem."

New Directions

Arch Linux does not have a concrete roadmap, which is deliberate. The core team maintains that "being able to assess and draw conclusions based on the current state and priorities makes us more flexible and adaptable. Most goals are primarily driven by the motivation of individuals [in the project]."

Still, Arch continues to evolve. Recently, it has added the code from Alexander Epaneshnikov's TalkingArch project into Archiso, the toolchain used in an Arch Linux installation. This development comes after major reworking of the code throughout 2020. According to the core team, during installation users can now "select an audio card by auditory feedback, and afterwards the console output is read to them using the speech synthesizer."

In addition, in the last few years, Arch Linux has been migrating its packaging code from SVN to Git and moving some sub-projects and its Kanban boards (a work organizing system) to its own GitLab in order to centralize the distribution's management. The core team would also like to find ways to "provide more optimized architectures, to have a better user-facing integration of the reproducible builds efforts, as well as a central and automatic way to detect upstream source releases for our packages." Like most distributions, Arch continues to be a work in progress.

So why should you consider Arch as your distribution? "The best part of Arch," its core team suggests, "is that the installation can be kept up to date with a single command without the need of painful periodic major upgrades. The official repositories contain over 11k packages for a wide range of general purpose needs. This includes non-free software like Steam even though all packages included in the base installer are free. Our packagers deliver updates frequently and timely (on average, 30-40 per day), and they are kept as close to the upstream releases as possible. This improves security and also means that configuring Arch is a transferrable skill." If you have learned how to configure something using Arch, chances are good that you can do the same task on most other distributions.

Just as importantly, Arch Linux's wiki maintains extensive documentation – more than 23,000 pages – as well as active user forums and a Reddit page. Considering how the distribution defines simplicity, leaving users to go their own way as much as possible, this support is essential. What is less well-known is that the available help is so comprehensive that often the users of other distributions can benefit from it as well.

Arch Linux has a reputation in some circles as a difficult distribution. However, as you start to use it, you may slowly realize that it is not so much difficult as different from many distributions. Stick with it, and you should start to realize that Arch is a distribution that puts you in control – a design principle that you can quickly learn to appreciate.