using-just

Using Just

Just is a command runner that executes recipes defined in a justfile.

Quick Start

# Run default recipe
just

# Run specific recipe
just build

# Run with arguments
just test integration

# Run multiple recipes
just clean build test

Listing Recipes

# List all recipes with descriptions
just --list

# List in file order (not alphabetical)
just --list --unsorted

# List with groups shown
just --list --groups

# One-line summary
just --summary

# Show recipe groups
just --groups

Running Recipes

# Run recipe from specific justfile
just -f path/to/justfile recipe

# Run from different directory
just -d /path/to/project recipe

# Set variables from CLI
just --set version "1.0.0" release

# Dry run (show commands without executing)
just --dry-run build

# Run without dependencies
just --no-deps test

# Run only one recipe (stop after first)
just -1 test1 test2

Interactive Mode

# Choose recipe interactively (requires fzf)
just --choose

# Use custom chooser
just --choose --chooser "fzf --multi"

# Auto-confirm prompts
just --yes dangerous-recipe

Inspecting Justfiles

# Show recipe source
just --show build

# Show recipe usage
just --usage deploy

# Evaluate and print variables
just --evaluate
just --evaluate version

# List all variables
just --variables

# Dump parsed justfile
just --dump
just --dump --dump-format json
just --dump --dump-format yaml

Working with Modules

# Run recipe from module
just module::recipe
just module recipe

# List module recipes
just --list module::

Editing & Setup

# Edit justfile in $EDITOR
just --edit

# Create starter justfile
just --init

# Format justfile (unstable)
just --fmt

# Check justfile syntax
just --check

Shell Completions

# Generate completions
just --completions bash > just.bash
just --completions zsh > _just
just --completions fish > just.fish
just --completions powershell > just.ps1

Common Options

Option	Short	Description
--justfile FILE	-f	Use specific justfile
--directory DIR	-d	Change to directory first
--working-directory DIR	-C	Set recipe working directory
--dry-run	-n	Show commands without running
--quiet	-q	Suppress output
--verbose	-v	Increase verbosity
--color MODE		auto, always, or never
--yes	-y	Auto-confirm prompts
--unstable		Enable unstable features

Environment Variables

Variable	Purpose
JUST_CHOOSER	Default chooser for --choose
JUST_UNSTABLE	Enable unstable features

Tips

• Just searches upward for justfiles, so you can run from subdirectories
• Use just --list frequently to see available recipes
• The --dry-run flag is useful for testing complex recipes
• just --show recipe reveals the actual commands