pkgmgr/scripts/nix

Nix Bootstrap (package-manager)

This directory contains the Nix initialization and bootstrap logic used by package-manager to ensure the nix command is available on supported systems (host machines and CI containers).

It is invoked during package installation (Arch/Debian/Fedora scriptlets) and can also be called manually.

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Entry Point

• scripts/nix/init.sh
  Main bootstrap script. It:
  • checks whether nix is already available
  • adjusts PATH for common Nix locations
  • installs Nix when missing (daemon install on systemd hosts, single-user in containers)
  • ensures predictable nix availability via symlinks (without overwriting distro-managed paths)
  • validates that nix is usable at the end (CI-safe)

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Library Layout

The entry point sources small, focused modules from scripts/nix/lib/:

• bootstrap_config.sh — configuration defaults (installer URL, retry timing)
• detect.sh — container detection helpers
• path.sh — PATH adjustments and nix binary resolution helpers
• symlinks.sh — user/global symlink helpers for stable nix discovery
• users.sh — build group/users and container ownership/perms helpers
• install.sh — installer download + retry logic and execution helpers

Each library file includes a simple guard to prevent double-sourcing.

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When It Runs

This bootstrap is typically executed automatically:

• Arch: post-install / post-upgrade hook
• Debian: postinst
• Fedora/RPM: %post

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Notes / Design Goals

• Cross-distro compatibility: supports common Linux layouts (including Arch placing nix in /usr/sbin).
• Non-destructive behavior: avoids overwriting distro-managed nix binaries.
• CI robustness: retry logic for downloads and a final nix availability check.
• Container-safe defaults: single-user install as a dedicated nix user when running as root in containers.