Install apptainer with Homebrew, apk, dnf, pacman, zypper, apt

Project links

• Homepage
• Repository
• Upstream docs
• Package manager page

Commands and aliases

• apptainer
• run-singularity
• singularity

Project history

The user guide says Apptainer was first developed at Lawrence Berkeley National Laboratory to run complex applications on HPC clusters in a simple, portable, and reproducible way. It became popular at HPC and academic sites before expanding into industry.

In November 2021, the project announced that Singularity was moving into the Linux Foundation and being renamed Apptainer to avoid confusion with other Singularity-named products and to keep the project under community governance. The announcement says the first Apptainer release would be 1.0 in a new GitHub repository.

The Apptainer changelog records v1.0.0 in March 2022. That release changed the primary executable from `singularity` to `apptainer`, renamed `/etc/singularity` to `/etc/apptainer`, migrated per-user configuration from `~/.singularity` to `~/.apptainer`, and retained a `singularity` command symlink for compatibility.

The v1.1.0 release in September 2022 made a major packaging and security shift: Apptainer no longer installed a setuid-root component by default, relying instead on unprivileged user namespaces for most operations and moving the setuid portion into optional packaging.

Adoption history

Apptainer's adoption is strongest in HPC because it maps container workflows onto shared clusters where Docker's daemon model, root privileges, and isolation defaults are often a poor fit. Its docs emphasize single-file SIF images, integration with GPUs and high-speed filesystems, and preserving the user's host identity by default.

The compatibility strategy helped adoption after the rename. Official docs describe SIF image compatibility, support for `SINGULARITY_` environment variables during transition, a `singularity` symlink to the same binary, and automatic user configuration migration.

Distribution packaging matters because Apptainer is used on managed systems: clusters often install it centrally, admins control global configuration under `/etc/apptainer` or `/usr/local/etc/apptainer`, and users keep remotes, keys, caches, and registry credentials under `~/.apptainer`.

How it is used

Users build, pull, run, shell into, and exec containers with the `apptainer` CLI. Typical sources include SIF files, Docker/OCI registries, ORAS endpoints, and definition files used to build reproducible scientific or commercial software environments.

Administrators tune `apptainer.conf` for setuid behavior, namespaces, bind mounts, networking, GPUs, cgroups, and helper binary paths. Remote endpoints and keyserver settings are managed through `remote.yaml`; login commands store endpoint credentials, and OCI registry credentials can live in `~/.apptainer/docker-config.json` or a custom `--authfile`.

Why package nerds care

Apptainer is a packaging story about containers for places where containers are infrastructure, not just developer convenience. It packages runtime policy, SIF image handling, OCI interop, user namespace tradeoffs, cluster admin controls, and backwards compatibility with a large Singularity install base.

For package nerds, the rename is especially interesting because the package intentionally ships compatibility: old command names, old environment variable prefixes, image-format stability, and migration from old user config directories. That reduced the blast radius of a governance and trademark-driven project transition.

Timeline

• 2017: User docs copyright history reflects the Sylabs/Singularity era.
• 2021: Community announcement says Singularity moved to the Linux Foundation and was renamed Apptainer.
• 2022: Changelog records Apptainer v1.0.0.
• 2022: Changelog records v1.1.0 changing the default away from setuid-root installation.
• 2024: Changelog records v1.3.x releases with OCI, packaging, and filesystem fixes.
• 2026: Main user/admin docs continue under the Apptainer project.

Related projects

• Singularity is the original project lineage and compatibility target.
• SingularityCE/Sylabs Singularity is the related fork/product line discussed in the rename announcement.
• SIF is the container image format shared across Apptainer and Singularity workflows.
• OCI/Docker registries and ORAS endpoints are supported container sources and publication targets.

Sources

• https://apptainer.org/docs/admin/main/configfiles.html
• https://apptainer.org/docs/user/main/cli/apptainer_remote_login.html
• https://apptainer.org/docs/user/main/introduction.html
• https://apptainer.org/docs/user/main/singularity_compatibility.html
• https://apptainer.org/news/community-announcement-20211130/
• https://github.com/apptainer/apptainer/blob/main/CHANGELOG.md