Installation

The canonical way to install CIDER is via package.el (Emacs’s built-in package manager), but it can be installed manually or via alternative package managers such as el-get.

Prerequisites

You’ll need to have Emacs installed, preferably the latest stable release. If you’re new to Emacs you might want to go through the guided tour of Emacs and the built-in tutorial (just press C-h t).

CIDER officially supports Emacs 25.1+, Java 8+ and Clojure(Script) 1.8+. CIDER 0.17 (AndalucĂ­a) was the final release which supported Java 7 and Clojure(Script) 1.7.

You’ll also need a recent version of either the Clojure CLI tools or your favorite build tool (Leiningen, Boot, or Gradle) to be able to start CIDER via cider-jack-in. Generally it’s a good idea to use the latest stable versions.

CIDER does not support ClojureCLR.

Installation via package.el

CIDER is available on the two major package.el community maintained repos - MELPA Stable and MELPA.

You can install CIDER with the following command:

M-x package-install <RET> cider <RET>

or by adding this bit of Emacs Lisp code to your Emacs initialization file (.emacs or init.el):

(unless (package-installed-p 'cider)
  (package-install 'cider))

If the installation doesn’t work try refreshing the package list:

M-x package-refresh-contents <RET>

It’s important to note that MELPA packages are built automatically from the master branch, and that means you’ll be right on the leading edge of development. This has upsides and downsides; you’ll see new features first, but you might experience some bugs from time to time. Nevertheless, installing from MELPA is a reasonable way to obtain CIDER. The master branch is normally quite stable and serious regressions there are usually fixed quickly.

If you have concerns about living on the leading edge of CIDER deveopment, you can always pin CIDER to use MELPA Stable like this:

(add-to-list 'package-pinned-packages '(cider . "melpa-stable") t)
If you don’t want to (or can’t) wait for MELPA to rebuild CIDER, you can easily build and install an up-to-date MELPA package locally yourself. Check out this article for details on the subject.
CIDER has dependencies (e.g. queue & seq) that are only available in the GNU ELPA repository. It’s the only package repository enabled by default in Emacs and you should not disable it!

Installation via use-package

use-package can be used to install CIDER via the package.el's repositories MELPA Stable and MELPA.

If you wanted to install the version of CIDER which is what is to be found in the master branch, declare the following in your Emacs initialization file (.emacs or init.el):

(use-package cider
  :ensure t)

However, if you wanted to be a bit more conservative and only use the stable releases of CIDER, you’d declare the following:

(use-package cider
  :ensure t
  :pin melpa-stable)

After placing one of the above s-expressions, evaluate it, for it to take effect by entering: C-x C-e.

For further configuration options with use-package, consult the official use-package repository.

Installation via el-get

CIDER is also available for installation from the el-get package manager.

Provided you’ve already installed el-get you can install CIDER with the following command:

M-x el-get-install <RET> cider <RET>

Manual Installation

Installing CIDER manually is discouraged unless you plan to work with CIDER’s codebase. The manual installation is relatively involved as it requires manual installation of the dependencies. Check out the section Hacking on CIDER for more details.