elpa-tuareg binary package in Ubuntu Lunar s390x

 Tuareg handles automatic indentation of Objective Caml and Caml-Light
 code. Key parts of the code are highlighted using Font-Lock. It
 provides support to run an interactive OCaml toplevel and debugger.
 .
 This mode attempts to give better results than the caml-mode provided by
 the elpa-caml package. Indentation rules are slightly different but
 closer to classical functional languages indentation. Tuareg
 gives access to some functionalities from caml-mode when the elpa-caml
 package is installed.

Source package