Installer alejandra avec Homebrew, Nix

Liens du projet

• Page d'accueil
• Dépôt
• Docs amont
• Page du gestionnaire de paquets

Commandes et alias

• alejandra

Historique du projet

The official README brands Alejandra as 'The Uncompromising Nix Code Formatter' and says it was written in Rust, formats Nixpkgs in seconds, and starts from the original Nixpkgs style refined by feedback from developers using Nix at scale.

The changelog shows a fast maturation arc in 2022. Version 1.0.0 shipped in March 2022; 1.4.0 and 1.5.0 followed with pre-commit support and dependency updates; 2.0.0 in July 2022 added a style guide, editor integration docs, and publication as a Rust crate with API docs; 3.0.0 in August 2022 simplified the CLI and improved large-file formatting order.

Later releases kept the formatter active in normal toolchain maintenance. Version 3.1.0 in 2024 refreshed integration docs and pre-commit hooks, and 4.0.0 in 2025 added experimental configurable indentation and support for newer Nix pipe operators.

Historique d'adoption

Alejandra's official README documents installation from Nixpkgs, Nix flakes, NixOS configurations, Homebrew, and prebuilt binaries. The supplied package facts also list Homebrew and Nix packages, which fits its primary audience: people already managing tools declaratively.

The README lists integrations for VS Code, Vim, Neovim, GNU Emacs, Doom Emacs, pre-commit, and pre-commit-hooks.nix. That adoption history matters because formatters become useful only when they are cheap to run in editors, CI, and repository hooks.

Modes d'utilisation

Users run `alejandra` against Nix files, stdin, or repository trees, and often wire it into editor format-on-save or pre-commit hooks. The project treats the CLI, formatting rules, flags, exit codes, and stdout as its public API under semantic versioning.

Configuration is intentionally limited. The README documents an experimental `alejandra.toml` discovered in the current working directory, or supplied explicitly with `--experimental-config`.

Pourquoi les passionnés de paquets s'y intéressent

Alejandra is a package-nerd package because it formats the language used to describe packages in Nix. It is both a normal CLI package and a tool that shapes the readability of package expressions.

It also has the useful distribution trifecta for developer tools: Rust source, prebuilt binaries, and native Nix/Homebrew packaging, plus editor and hook integrations.

Chronologie

• 2022-03-03: Alejandra 1.0.0 released.
• 2022-05-19: Alejandra 1.4.0 added a pre-commit hook.
• 2022-07-13: Alejandra 2.0.0 added a style guide, editor integration docs, and crates.io publication.
• 2022-08-14: Alejandra 3.0.0 simplified the CLI and improved large-file formatting order.
• 2024-11-03: Alejandra 3.1.0 refreshed docs and pre-commit integration.
• 2025-04-10: Alejandra 4.0.0 added configurable indentation and Nix pipe-operator support.

Related projects

• The official README names NixEL, Santiago, and rnix-parser as related libraries.
• The README lists nixfmt, serokell/nixfmt, and nixpkgs-fmt as formatter alternatives in the same ecosystem.

Sources

• https://github.com/kamadorueda/alejandra/blob/main/CHANGELOG.md
• https://github.com/kamadorueda/alejandra/blob/main/README.md
• https://kamadorueda.com/alejandra
• source_facts.package-manager