just

command runner similar to make but focused on running project-specific

TLDR

List available recipes

$ just --list

Run the default recipe

$ just

Run a specific recipe

$ just [recipe_name]

Run with arguments

$ just [recipe_name] [arg1] [arg2]

Run from a specific justfile

$ just --justfile [path/to/justfile] [recipe]

Show what would run without executing

$ just --dry-run [recipe]

Evaluate and print all variables

$ just --evaluate

Run recipe in specific directory

$ just --working-directory [path] [recipe]

SYNOPSIS

just [options] [recipe] [arguments ...]

just is a command runner similar to make but focused on running project-specific commands rather than building targets. It uses a justfile (similar to Makefile) to define recipes - named sets of commands.Recipes are defined with a name, optional parameters, and body of shell commands. Unlike make, just doesn't track file dependencies or timestamps; it simply runs the specified commands. This makes it ideal for task automation, development workflows, and project scripts.Variables can be defined and used with {{variable}} syntax. Environment variables are accessible, and recipes can export variables. Conditionals, default values, and error handling are supported.Just supports multiple shells (sh, bash, powershell, python, etc.) per recipe via shebang-like syntax. Recipes can have dependencies (other recipes to run first), and private recipes (prefixed with _) are hidden from --list.Cross-platform support means justfiles work on Linux, macOS, and Windows. The tool is fast (written in Rust) and has no dependencies.

PARAMETERS

-l, --list

List available recipes.

-n, --dry-run

Print what would be executed without running.

--evaluate

Evaluate and print all variables.

-f, --justfile path

Use specified justfile.

-d, --working-directory path

Run from specified directory.

--set var value

Override variable value.

--chooser program

Use program to select recipe interactively.

--choose

Select recipe with chooser.

-s, --show recipe

Show recipe definition.

--summary

List recipes one per line.

--dump

Print justfile in canonical form.

--fmt

Format justfile.

--check

Check justfile for errors.

-q, --quiet

Suppress echoing of recipe lines.

-v, --verbose

Verbose output.

--color when

Color output: auto, always, never.

--shell shell

Shell to use for recipes.

INSTALL

sudo apt install just

sudo dnf install just

sudo pacman -S just

sudo apk add just

sudo zypper install just

brew install just

nix profile install nixpkgs#just

CAVEATS

Not a build system - no incremental builds or dependency tracking. Different from make syntax despite similarities. Shell differences may affect cross-platform recipes. Variable scope differs from make. Comments use # (not supported in all recipe positions).

HISTORY

just was created by Casey Rodarmor starting around 2016 as a simpler alternative to make for running commands. Frustrated with make's complexity and focus on building (rather than running), he designed just for the common use case of project-specific task running. The tool has gained popularity in the Rust community and beyond.