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just

A handy way to save and run project-specific commands.

just reads a Justfile that lists named recipes (commands or command sequences) for a project and runs them on demand. It is similar in spirit to Make targets but without Make's file-modification semantics: just recipes are simply named commands, not "rebuild this file from these prerequisites". The result is a clean, self-documenting place to put project scripts.

The Justfile syntax is friendlier than Makefile syntax: variables work intuitively, recipes can take arguments and have descriptions for "just --list" output, and recipe bodies are shell scripts (or any other interpreter) without the tab-only indentation rule that traps Makefile newcomers.

Casey Rodarmor wrote just in Rust starting in 2016. It is CC0-licensed (public domain dedication), packaged in most major Linux distributions, and increasingly common in modern Rust, Go, and Python project repositories as the place where "developer scripts" live. It pairs well with direnv (for per-project environment variables) and mise/asdf (for runtime version management).

Debian/Ubuntu: see https://github.com/casey/just#installation
Arch:          sudo pacman -S just
macOS:         brew install just