dune binary package in Ubuntu Lunar amd64

 Dune is a build system designed for OCaml/Reason projects
 only. It focuses on providing the user with a consistent experience
 and takes care of most of the low-level details of OCaml
 compilation. All you have to do is provide a description of your
 project and Dune will do the rest.
 .
 ocaml-dune was previously called dune; this is a transitional package,
 which can be safely removed.

Source package