whoneeds

whoneeds shows all installed Arch Linux packages that directly or transitively depend on another installed package, grouped by whether they were explicitly or automatically installed.

It preserves the historical command interface:

whoneeds <package-name>

Example output:

Explicitly installed packages that depend on [zlib]
  pacman
Other installed packages that depend on [zlib]
  curl

When no installed dependents are found, it prints:

Packages that depend on [zlib]
  None

Backend

whoneeds is implemented in safe Rust and delegates package graph discovery to official Arch tooling:

• pactree -lru <package> from pacman-contrib lists reverse dependencies.
• pacman -Qqe lists explicitly installed packages.

The queried package itself is removed from the reverse-dependency set. The remaining packages are sorted into an explicitly installed group and an automatically installed group. Empty groups are omitted.

Development Checks

make check

The repository includes .githooks/pre-commit, which runs the same formatter, tests, and pedantic Clippy checks used by make check.

Enable the tracked hook in this clone with:

git config core.hooksPath .githooks

Installation

make install DESTDIR="$pkgdir" PREFIX=/usr

Runtime dependency on Arch Linux:

• pacman-contrib