1. Howard Lewis Ship
  2. clojuresque



clojuresque – a Clojure plugin for Gradle

What is Gradle?

Gradle is a build system written in Java and Groovy. One advantage of Gradle is, that the build script itself is also a Groovy script. That means whatever can be done in Groovy can be done in the build script. This is useful to abstract away common patterns in the build like repetition or conditional decisions.

On top of that Gradle provides a convenient build system which comes in form of different plugins. Each plugin defines certain conventions which (if followed) automasie 95% of the build completely. Still the conventions are freely configurable to be adapted to different project structures.

What is clojuresque?

clojuresque is now a plugin for Gradle, which adds Clojure support. It allows compilation with automatic namespace recognition. The plugin is based on the Java plugin and hooks into the standard configurations and archives.

Contrary to the Groovy plugin, there is no special groovy configuration. Java code in the same project might want to hook into [Clojure][] as well. So the [Clojure][] jar must be available also to the Java portion of the project.


  • Automatic recognition of namespaces only works if the ns form is the first in the file. Comments may precede the form. The symbol is allowed to be fully qualified: clojure.core/ns.

  • Clojars deployment is currently broken, because the clojars server does not like a single Java implementation of ssh. With other servers like the „real“ ssh it works quite well, though. I suspect the issue to be on the clojars side.


Create a build.gradle script in the root directory of your project. Note that gradle derives the project name from the name of this directory!

buildscript {
    repositories {
        mavenRepo name: 'clojars', urls: 'http://clojars.org/repo'
    dependencies {
        classpath 'clojuresque:clojuresque:1.4.1'

group = 'example.group'
version = '1.0.0'

apply plugin: 'clojure'

warnOnReflection = true
aotCompile = true

repositories {

dependencies {
    compile 'org.clojure:clojure:1.2.1'

A small walkthrough:

  • The buildscript part defines a dependency and automatically fetches clojuresque from Clojars.
  • The group and version properties define the respective attributes of your project. They are required for the POM generation.
  • apply basically loads the clojure plugin.
  • warnOnReflection turns on the reflection warnings of the clojure compiler
  • aotCompile specifies whether to produce a source jar or an AOT compiled jar. The default is produce a source jar, because they also tend to be smaller. This issue was discussed on the Google group.
  • clojarsRepo adds the Clojars Repository.
  • In the dependencies section we add a dependency on clojure.


In the filesets you can specify filters with include resp. exclude. This is fine for mostly file based languages. However clojure is strongly based on namespaces. Therefor the clojure part of the source sets support also clojureIncludeNamespace and clojureExcludeNamespace which can be used to filter on the namespace name. Eg. to exclude examples from the final jar one could use

sourceSets.main.clojure {
    clojureExcludeNamespace 'my.project.examples.**.*'

Clojars Deployment

Note: Does work only on Unix/Mac OS via shell out to scp. Does not work on Windows! Make sure you have an agent running which handles your clojars key.


As Leiningen, Clojuresque now supports uberjars. That means you can enable the uberjar task with

uberjar.enabled = true

Then invoking gradle ueberjar will create a jar file with all runtime dependencies included.


This is alpha software! Expect problems! Please report issues in the bugtracker at the lighthouse tracker. Or email them to me.

General support is available on the clojuresque google group.

-- Meikel Brandmeyer mb@kotka.de Frankfurt am Main, January 2010