ocaml-base binary package in Ubuntu Bionic armhf

 Objective Caml (OCaml) is an implementation of the ML language, based on
 the Caml Light dialect extended with a complete class-based object system
 and a powerful module system in the style of Standard ML.
 .
 This package contains only the runtime system needed to run bytecode
 executables. The 'ocaml' package contains the full development suite of
 Objective Caml. You may wish to install the 'ocaml-base-nox' package if
 you do not require any graphical capabilities for your runtime.

Source package