Grunt - the JavaScript task runner

GruntJS is a JavaScript based command line build tool that helps to automate repetitive tasks.

GruntJS logoGrunt is a task-based command line build tool that assists in automating grunt tasks for their JavaScript projects. There are a lot of repetitive but necessary tasks that developers have to do to maintain their projects. The more projects there are, the more mundane such tasks become. Now developers can automate such processes as minification, concatenation, compilation, unit testing, linting and many more. Grunt is a task runner with which it is possible to avoid performing such chores.

Grunt is written in JavaScript, built on top of Node.js, and is cross-platform (works on OS X, Linux and Windows). Its core consists of small command line client and core task runner. Developer can use the basic functions for the project to:

  • concatenate files;
  • run unit tests with nodeunit;
  • generate project scaffolding from a predefined template;
  • validate files with JSHint;
  • minify files with UglifyJS;
  • run QUnit unit tests in a headless PhantomJS instance;
  • run predefined tasks whenever watched files change.
  • start a static web server;

All other functionality is stored in plugins, so Grunt can easily be customized to suit needs of any particular project. Grunt has plugins for:

  • minification of JavaScript, CSS, Less, HTML, SVG;
  • compiling Sass/Less/Stylus files to CSS, and CoffeeScript/LiveScript to JS;
  • PNG and JPEG file size optimization;
  • automatic inlining and spriting of images;
  • optimization for Require.js and Google Closure Compiler;
  • precompilation of Handlebars, Jade, Underscore, Mustache, Eco or Hogan templates;
  • running tests using Sauce Labs (supports QUnit, Jasmine, Mocha and YUI tests).

There are already hundreds of plugins to choose from, so Grunt can be used to automate just about anything with little effort. List of plugins is regularly updated (when a new Node.js module with the keyword “gruntplugin“ is published, it is automatically added to the list).

Grunt is a JavaScript-based command line build tool for automation of repetitive tasks. Grunt is very consistent and helps developers be more productive, especially those who work in teams and want to write code to the same standard. If you want to learn more, visit

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