The company Collabora has introduced the Holo Core project, in collaboration with Valve, which has prepared a special edition of the Arch Linux distribution for the AArch64 platform. Holo Core is designed for use with SteamOS on the Steam Frame device, which combines a personal computer, a 3D headset, and two 3D controllers. The development of Holo Core was necessary because the Arch Linux distribution, which serves as the basis for SteamOS, is only available for the x86_64 architecture, while the Steam Frame device is built on the Snapdragon 8 chip, utilizing the ARM64 architecture. For testing, the source code of packages adapted for the ARM64 architecture is available, as well as precompiled binary package builds and a container image in Docker format.
The key task of the project is to build a continuous integration infrastructure for organizing automated builds that monitor the state of continuously updated Arch Linux repositories and determine the required dependencies. In addition to creating patches necessary for the functioning of certain packages on Aarch64 systems, several issues needed to be addressed during the implementation of the project.
Some of the issues arise because the new state of certain packages in the continuously updated Arch Linux repository is tied to an old one, and to build it, the entire chain of states must be reproduced (for example, to rebuild rust 1.91, rust 1.90 must be present, which in turn requires rust 1.89, and so on). A similar situation is observed for the libraries that the build tooling depends on (such as icu and gpgme used by pacman) — in the event of version updates for these libraries, both the old and new versions must be available for a successful rebuild.
Another constraint has been the uncertainty surrounding the build order — in the Arch Linux Git repository, packages are often added in a non-sequential manner, making it unsuitable for automated rebuilding without recalculating the entire dependency chain. Additionally, attempts to build older versions face obstacles due to changes in the infrastructure of upstream projects — the source code may be moved, the project may switch to another Git hosting, checksums on the code in Git may change due to the replacement of short hashes with long ones, and automated uploads may be blocked by anti-bot protection.
The CI toolset developed as part of the Holo Core project is capable of computing the entire dependency tree and 'replaying' the build history of Arch Linux from the initial bootstrap to a selected state, covering all necessary intermediate rebuilds. The published test version corresponds to the package versions in the Arch Linux repository as of November 18, 2025, and serves as a prototype demonstrating the readiness of the infrastructure created for producing final products.
Once the system is debugged, it is planned to synchronize it with the package versions used in the development of future versions of SteamOS for the x86_64 architecture. The code of the developed CI tool will be released under an open license and proposed for integration into the Arch Linux project, which currently lacks CI infrastructure. The main project also plans to transfer the findings for creating an official port of Arch Linux for the AArch64 architecture.
Source: opennet.ru
