[Grails][Grails] is a framework used to build web applications with the [Groovy][Groovy] programming language. The core framework is very extensible and there are numerous [plugins][plugins] available that provide easy integration of add-on features. [Grails]: http://grails.org/ [Groovy]: http://groovy.codehaus.org/ [plugins]: http://grails.org/plugins/
You need a Java Development Kit (JDK) installed, but it is not necessary to install Groovy because it's bundled with the Grails distribution.
To install Grails, visit http://grails.org/Download and download the version you would like to use. Set a GRAILS_HOME environment variable to point to the root of the extracted download and add GRAILS_HOME/bin to your executable PATH. Then in a shell, type the following:
grails create-app sampleapp
cd sampleapp
grails run-app
To build Grails, clone this GitHub repository and then in a shell, type the following:
./gradlew install
Grails and Groovy are licensed under the terms of the [Apache License, Version 2.0][Apache License, Version 2.0]. [Apache License, Version 2.0]: http://www.apache.org/licenses/LICENSE-2.0.html