# Leiningen Leiningen logo > "Leiningen!" he shouted. "You're insane! They're not creatures you can > fight—they're an elemental—an 'act of God!' Ten miles long, two > miles wide—ants, nothing but ants! And every single one of them a > fiend from hell..." > - from Leiningen Versus the Ants by Carl Stephenson Leiningen is for automating Clojure projects without setting your hair on fire. ## Installation If your preferred [package manager](https://github.com/technomancy/leiningen/wiki/Packaging) has a relatively recent version of Leiningen, try that first. Otherwise you can install by hand: Leiningen bootstraps itself using the `lein` shell script; there is no separate install script. It installs its dependencies upon the first run on unix, so the first run will take longer. 1. [Download the script](https://raw.github.com/technomancy/leiningen/preview/bin/lein). 2. Place it on your `$PATH`. (I like to use `~/bin`) 3. Set it to be executable. (`chmod 755 ~/bin/lein`) The link above will get you the 2.x preview release. There is still a lot of extant material on the Web concerning the older [Leiningen 1.x](https://raw.github.com/technomancy/leiningen/stable/bin/lein) version, which is still available if you need to work on older projects that aren't compatible with 2.x yet. The [upgrade guide](https://github.com/technomancy/leiningen/wiki/Upgrading) has instructions on migrating to version 2. On Windows most users can get [the batch file](https://raw.github.com/technomancy/leiningen/preview/bin/lein.bat). If you have wget.exe or curl.exe already installed and in PATH, you can just run `lein self-install`, otherwise get the standalone jar from the [downloads page](https://github.com/technomancy/leiningen/downloads). If you have [Cygwin](http://www.cygwin.com/) you should be able to use the shell script above rather than the batch file. ## Basic Usage The [tutorial](https://github.com/technomancy/leiningen/blob/preview/doc/TUTORIAL.md) has a detailed walk-through of the steps involved in creating a new project, but here are the commonly-used tasks: $ lein new [TEMPLATE] NAME # generate a new project skeleton $ lein test [TESTS] # run the tests in the TESTS namespaces, or all tests $ lein repl # launch an interactive REPL session $ lein run -m my.namespace # run the -main function of a namespace $ lein uberjar # package the project and dependencies as standalone jar Use `lein help` to see a complete list. `lein help $TASK` shows the usage for a specific task. You can also chain tasks together in a single command by using the `do` task with comma-separated tasks: $ lein do clean, test foo.test-core, jar Most tasks need to be run from somewhere inside a project directory to work, but some (`new`, `help`, `search`, `version`, and `repl`) may run from anywhere. See the [FAQ](https://github.com/technomancy/leiningen/blob/master/doc/FAQ.md) for more details. ## Configuration The `project.clj` file in the project root should look like this: ```clj (defproject myproject "0.5.0-SNAPSHOT" :description "A project for doing things." :url "http://github.com/technomancy/myproject" :dependencies [[org.clojure/clojure "1.4.0"]] :plugins [[lein-ring "0.4.5"]]) ``` The `lein new` task generates a project skeleton with an appropriate starting point from which you can work. See the [sample.project.clj](https://github.com/technomancy/leiningen/blob/preview/sample.project.clj) file (also available via `lein help sample`) for a detailed listing of configuration options. The `project.clj` file can be customized further with the use of [profiles](https://github.com/technomancy/leiningen/blob/master/doc/PROFILES.md). ## Plugins Leiningen supports plugins which may contain both new tasks and hooks that modify behaivour of existing tasks. See [the plugins wiki page](https://github.com/technomancy/leiningen/wiki/Plugins) for a full list. If a plugin is needed for successful test or build runs, (such as `lein-tar`) then it should be added to `:plugins` in project.clj, but if it's for your own convenience (such as `swank-clojure`) then it should be added to the `:plugins` list in the `:user` profile from `~/.lein/profiles.clj`. See the [profiles guide](https://github.com/technomancy/leiningen/blob/preview/doc/PROFILES.md) for details on how to add to your user profile. The [plugin guide](https://github.com/technomancy/leiningen/blob/preview/doc/PLUGINS.md) explains how to write plugins. ## Contributing Please report issues on the [GitHub issue tracker](https://github.com/technomancy/leiningen/issues) or the [mailing list](http://librelist.com/browser/leiningen/). Personal email addresses are **not** appropriate for bug reports. See the [readme for the leiningen-core library](https://github.com/technomancy/leiningen/blob/master/leiningen-core/README.md) and `doc/PLUGINS.md` for more details on how Leiningen's codebase is structured. Design discussions also occur in the [#leiningen channel on Freenode](irc://chat.freenode.net#leiningen). Patches are preferred as GitHub pull requests, though patches from `git format-patch` are also welcome on the mailing list. Please use topic branches when sending pull requests rather than committing directly to master in order to minimize unnecessary merge commit clutter. Contributors who have had a single patch accepted may request commit rights on the mailing list or in IRC. Please use your judgment regarding potentially-destabilizing work and branches. Other contributors will usually be glad to review topic branches before merging if you ask on IRC or the mailing list. Contributors are also welcome to request a free [Leiningen sticker](http://twitpic.com/2e33r1) by asking on the mailing list and mailing a self-addressed, stamped envelope. ## Building You don't need to "build" Leiningen per se, but when you're using a checkout you will need to get its dependencies in place. For the master branch, use Leiningen 1.x to run `lein install` in the `leiningen-core` subproject directory. When the dependencies change you will also have to do `rm .lein-classpath` in the project root. Once you've done that, symlink `bin/lein` to somewhere on your `$PATH`, usually as `lein2` in order to keep it distinct from your existing installation. If you want to develop on the 1.x branch, this should be unnecessary. ## License Source Copyright © 2009-2012 Phil Hagelberg, Alex Osborne, Dan Larkin, and [contributors](https://github.com/technomancy/leiningen/contributors). Distributed under the Eclipse Public License, the same as Clojure uses. See the file COPYING. Thanks to Stuart Halloway for Lancet and Tim Dysinger for convincing me that good builds are important. Images Copyright © 2010 Phil Hagelberg. Distributed under the Creative Commons Attribution + ShareAlike License. [Full-size version](https://github.com/downloads/technomancy/leiningen/leiningen-full.jpg) available.