I have been missing this feature for a while and noticed it had already been requested before (2014), See: https://lists.gnu.org/archive/html/emacs-orgmode/2016-08/msg00105.html With this patch you can switch between using jar or plantuml. The idea partly stemmed from plantuml-mode and my inability to use the default implementation. You can see the implementation for plantuml-mode here: https://github.com/skuro/plantuml-mode/pull/102/files My patch is available here: https://code.orgmode.org/terlar/org-mode/commit/fbe245c0b09513ee5a6d3b189e112708b9d08da0 And also see attached within this mail.