Automic VaultAutomic Vault

brew

Install alejandra with Homebrew, Nix

Command-line tool for formatting Nix Code. Version 4.0.0 via Homebrew; verified from local package data.

Install commandSecurity notes

install

Additional install commands

macOS

Homebrewverified · 100%
brew install alejandra

local Homebrew formula metadata

Linux

Nixverified · 92%
nix profile install nixpkgs#alejandra

nixpkgs package indexes · pkgs/by-name/al/alejandra/package.nix · source: api.github.com

overview

Package summary

Command-line tool for formatting Nix Code

Commands and aliases

  • alejandra

history

Project history and usage

Alejandra is a Rust-based formatter for the Nix expression language. It is part of the Nix ecosystem's formatter wars: small, opinionated, fast, and built to make style disappear from code review.

Project history

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.

Adoption history

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.

How it is used

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`.

Why package nerds care

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.

Timeline

  • 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.

security posture

Risk level: green

narrow executable package without higher-risk signals.

Risk classifier

green risk · low confidence · appliance

Why

  • narrow executable package without higher-risk signals

Signals

  • metadata:no-higher-risk-signals

Install behavior

  • No Homebrew post-install hook is recorded in formula metadata.
  • Homebrew bottle metadata is available for 8 platform targets.
  • Build metadata lists 1 build dependencies.

Recommended review

Before unattended agent use, check whether the tool reads plaintext credentials, writes remote state, publishes artifacts, or shells out to plugins.

local files

Configuration and credential file locations

These source-backed paths show where this package keeps local settings or durable credentials. Automic Vault can use them as review targets for secret scanning, migration, and command approval.

Configuration files

Config paths the tool may read or write during local use.

Unix
alejandra.toml

executables

Installed executables

CommandKindExposureNote
alejandracliglobal executable

freshness

Version and freshness

These signals separate page generation age, package-manager activity, and upstream release comparison. Version lag is warned only when an evidence URL and comparable versions are present.

page generated2026-07-08
manager version4.0.0
manager updated
local dataok
upstreamcurrent
latest detected4.0.0

https://github.com/kamadorueda/alejandra

  • infoNo package-manager update timestamp was available.low confidence

install metadata

Package metadata

Package keybrew:alejandra
Version4.0.0
Package managerHomebrew
Package manager pagehttps://formulae.brew.sh/formula/alejandra
Homepagehttps://kamadorueda.com/alejandra/
Repositoryhttps://github.com/kamadorueda/alejandra
Upstream docshttps://github.com/kamadorueda/alejandra#readme
LicenseUnlicense
Source archivehttps://github.com/kamadorueda/alejandra/archive/refs/tags/4.0.0.tar.gz
Build dependenciesrust
Bottleavailable (on arm64_linux, arm64_sequoia, arm64_sonoma, arm64_tahoe, arm64_ventura, sonoma, ventura, x86_64_linux)
Homebrew post-installnot defined
Servicenone declared

registry facts

Source database details

Source DatabaseHomebrew formula API
Taphomebrew/core
Full Namealejandra
Version Scheme0
Revision0
Head VersionHEAD
Bottle Stable Root URLhttps://ghcr.io/v2/homebrew/core
Deprecatedno
Disabledno
Keg Onlyno
URL Keys
  • head
  • stable

source database matches

Other package-manager records

Matches are pulled from external package-manager indexes and kept separate from local Automic Vault package links.

Nix95%

alejandra

nix profile install nixpkgs#alejandra
  • normalized package name match
  • Matched by: Alejandra
nixpkgs package indexes · api.github.com · nixpkgs package indexes: pkgs/by-name/al/alejandra/package.nix from https://api.github.com/repos/NixOS/nixpkgs/git/trees/master?recursive=1

package graph

Links come from deterministic package relationships, av.db category and tag curation, ecosystem matches, and package hub membership.

Related tools

  • rustBuild dependency declared by Homebrew.

Same workflow

  • airShares av.db curated category or tags: cli, code-formatting, code-quality, developer-tools, formatter.
  • google-java-formatShares av.db curated category or tags: cli, code-formatting, code-quality, developer-tools, formatter.
  • astyleShares av.db curated category or tags: cli, code-formatting, developer-tools, formatter.
  • blackShares av.db curated category or tags: cli, code-formatting, developer-tools, formatter.
  • cbfmtShares av.db curated category or tags: cli, code-formatting, developer-tools, formatter.
  • darkerShares av.db curated category or tags: cli, code-formatting, developer-tools, formatter.

source trail

Generated from repository data

This page is generated by av-web from the private package SQLite artifact built by scripts/generate-pkg-sqlite.py.

Used sources

  • Geiger risk classifier
  • Nucleus package database
  • av.db category and tag curation
  • cross-ecosystem install command graph
  • curated configuration and credential file locations
  • curated package history
  • external package-manager database matches
  • package relationship graph
  • package version freshness
  • package-page enrichment