Code that you can add to your app's BuildConfig to enable you to specify in-place plugins outside of source controlled files

ExternalInPlacePlugin_BuildConfig.groovy

def buildConfigFile = new File("${userHome}/.grails/${appName}-buildConfig.groovy")
if (buildConfigFile.exists()) {
	println "Processing external build config at $buildConfigFile"
	def slurpedBuildConfig = new ConfigSlurper().parse(buildConfigFile.toURL())
	slurpedBuildConfig.grails.plugin.location.each { k, v -> 
		if (!new File(v).exists()) {
			println "WARNING: Cannot load in-place plugin from ${v} as that directory does not exist."
		} else {
			println "Loading in-place plugin $k from $v"
			grails.plugin.location."$k" = v
		}
		if (grailsSettings.projectPluginsDir?.exists()) {
			grailsSettings.projectPluginsDir.eachDirMatch(~/${k}.*/) {dir ->
				println "WARNING: Found a plugin directory at $dir that is a possible conflict and may prevent grails from using the in-place $k plugin."
			}
		}			
	}
}