lets¶

A declarative CLI builder. Define commands in KDL, get a production-quality CLI instantly.

description "My project tasks"

build "cargo build"
test "cargo test"
lint "cargo clippy -- -D warnings"

db {
    description "Database commands"
    migrate "diesel migration run"
    reset "diesel database reset"
}

$ lets --help
My project tasks

Commands:
  build
  test
  lint
  db     Database commands

$ lets db migrate
Running migration...

No code. No build step. Just a config file.

Why lets?¶

Most task runners make you choose between simplicity and power. Simple tools like make give you targets but no help text, no typed arguments, no completions. Powerful tools require learning a scripting language or a complex YAML schema.

lets gives you the UX of a hand-written clap CLI — colored help, typo suggestions, tab completion, typed arguments — from a config file you can write in under a minute.

	lets	Make	just	task
Config format	KDL	Makefile	Justfile	YAML
Typed args & flags	Yes	No	Limited	Limited
Shell completions	Auto-generated	No	Manual	Manual
Nested subcommands	Yes	No	No	Yes
Parallel deps	Yes	Yes	No	Yes
Interactive prompts	Built-in	No	No	No
Help text	Auto-generated	No	Yes	Yes
Arg validation	Choices, types	No	No	No

Install¶

cargo install lets-cli

Quick start¶

# Generate a starter lets.kdl for your project
lets self init

# Set up shell completions (add to your .zshrc/.bashrc)
eval "$(lets self setup)"

# See what's available
lets --list

# Run a command
lets build

Ready to dive in? Start with the Getting Started guide.