We often need to fix a bug in a gradle library (usually simplyhtml, mnemonicsetter),
where, without that feature, we need to build simplyhtml, pull the jar into freeplane
(by publishing the jar or copying the jar and changing to a local dep).
With composite builds, you can tell the freeplane build to include the simplyhtml build
(--include-build ../simplyhtml), allowing to just compile simplyhtml changes before building freeplane.
I haven't yet tried this out, maybe changes to the simplyhtml build system are necessary.
Of course, this is mainly beneficial to huge included builds.