Git-Like Interface Command Line Parser

GLI is the best way to make a “command-suite” command-line application, e.g. one like git (for the best way to make a simpler command-line application, check out methadone).

GLI allows you to make a very polished, easy-to-maintain command-line application without a lot of syntax, but without restricting you in any way from the power of OptionParser.

Build Status


Install if you need to:

gem install gli

The simplest way to get started is to create a scaffold project

gli init todo list add complete

This will create a basic scaffold project in ./todo with:

  • executable in ./todo/bin/todo. This file demonstrates most of what you need to describe your command line interface.

  • an empty test in ./todo/test/default_test.rb that can bootstrap your tests

  • an empty feature in ./todo/features/todo.feature that can bootstrap testing your CLI via Aruba.

  • a gemspec shell

  • a README shell

  • Rakefile that can generate RDoc, package your Gem and run tests

  • A Gemfile suitable for use with Bundler to manage development-time dependencies

Now, you are ready to go:

> cd todo
> bundle exec bin/todo help
    todo - Describe your application here

    todo [global options] command [command options] [arguments...]


    -f, --flagname=The name of the argument - Describe some flag here (default: the default)
    --help                                  - Show this message
    -s, --[no-]switch                       - Describe some switch here

    add      - Describe add here
    complete - Describe complete here
    help     - Shows a list of commands or help for one command
    list     - Describe list here

> bundle exec bin/todo help list
    list - Describe list here

    todo [global options] list [command options] Describe arguments to list here

    -f arg - Describe a flag to list (default: default)
    -s     - Describe a switch to list

All you need to do is fill in the documentation and your code; the help system, command-line parsing and many other awesome features are all handled for you.

Get a more detailed walkthrough on the main site

Supported Platforms

Known to work on

  • 1.8.7

  • 1.9.2

  • 1.9.3

  • 2.0.0

  • Ruby Enterprise Edition 1.8.7

  • Rubinius 1.0.1

  • JRuby 1.6.4

If you're interested in other versions of Ruby, let me know, and I'll add them to my test suite


Extensive documentation is available at the wiki.

API Documentation is available here. Recommend starting with GLI::DSL or GLI::App.



Dave Copeland (davetron5000 at g mail dot com)


Copyright © 2010 by Dave Copeland


Distributes under the Apache License, see LICENSE.txt in the source distro

gli CLI documentation