TL;DR: I’m replacing all of my Makefiles with Justfiles. All of the boilerplate I’ve had in my Makefiles is just handled. I love it.

What is Just? Link to heading

Just is a command runner, not a build system. It uses a file called justfile (or Justfile) to define recipes (commands) that you can run with just <recipe-name>. Think of it as a modern, sane replacement for make when all you really want is a way to run project commands.

Why Replace Make? Link to heading

If you’ve ever used a Makefile purely as a command runner, you know the pain:

  • .PHONY targets everywhere because you’re not actually building files
  • Tab-only indentation that silently breaks things if you use spaces
  • Arcane syntax for variables and string manipulation
  • No built-in way to list available targets
  • Recipes run each line in a separate shell by default

Just eliminates all of this. Here’s a comparison:

Makefile:

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.PHONY: build serve clean

build:
 hugo --minify

serve:
 hugo server -D

clean:
 rm -rf public/

Justfile:

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build:
    hugo --minify

serve:
    hugo server -D

clean:
    rm -rf public/

No .PHONY. No gotchas. Just commands.

Features I Like Link to heading

  • just --list shows all available recipes with descriptions
  • Comments as documentation - add a comment above a recipe and it shows in --list
  • Variables and interpolation work intuitively
  • Arguments to recipes are straightforward
  • OS detection built in for cross-platform recipes
  • Recipes run in the same shell by default (no more && chaining between lines)
  • Spaces or tabs for indentation - your choice

Example Link to heading

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# Run the development server
serve:
    hugo server -D

# Build for production
build:
    hugo --minify

# Run linting
lint:
    markdownlint content/posts/*.md

# Create a new post
new name:
    hugo new posts/$(date +%Y-%m-%d)-{{name}}.md

Running just --list outputs:

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Available recipes:
    build # Build for production
    lint  # Run linting
    new   # Create a new post
    serve # Run the development server

Installation Link to heading

Available via most package managers:

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# macOS
brew install just

# cargo
cargo install just

# many more at https://github.com/casey/just#installation

I hope this helps someone. Cheers.