Yes, there is. Grails 3 is based on Gradle so multi-project gradle builds solve your issue.
Basically you add dependency as:
compile project(':../my-custom-plugin')
and has to modify settings.gradle
to include plugin:
include '../my-custom-plugin'
Check Grails documentation on Plugins and Multi-Project Builds
in http://grails.github.io/grails-doc/latest/guide/plugins.html
Other way is to install plugin in local maven repository using gradle publishToMavenLocal
command and resolve if from there, before publishing to Bintray or other dependency repository.
Additionally since Grails 3.1.1, reloading is now supported for 'inline' plugins. Check https://github.com/grails/grails-core/releases/tag/v3.1.1 and http://grails.io/post/138665751278/grails-3-gradle-multi-project-builds
It is done using grails { plugins {
syntax. Copied from docs:
grails {
plugins {
compile ":hibernate"
compile project(':myplugin')
}
}