This subproject is required for all Grails 3 applications and plugins that require GSP processing. If your project includes GSPs you should add the following to your build.gradle which is provided by the Grails Gradle Plugin.
apply plugin: "org.grails.grails-gsp"
It is typical of standard Grails 3 application to use this in conjunction with grails-web as in the following example:
apply plugin: "org.grails.grails-web" apply plugin: "org.grails.grails-gsp"
To see what additional subprojects will be included with this, you can view this project's build.gradle