Alternative to `libsDir`

How to do the same thing from a snippet that does a few subprojects to gather all the jars for a project into a staging directory like so

subprojects {
…
…
task syncJars(type: Sync, dependsOn: ‘jar’) {
from(configurations.compile) {}
from(fixedLibDir) {}
from(libsDir) {}
into toStagingDir
}

}

I am not sure how to convert libsDir in this case