There's no reason not to use the latest release. Could you scnd an updated patch for the latest release, with a comment saying future versions will use dune?

There seem to be some whitespace issues with your patch. Tabs?

Le 9 décembre 2020 09:58:35 GMT-05:00, divoplade <d@divoplade.fr> a écrit :
Dear guix,

I want to have js_of_ocaml into guix. Here is a dependency of it,
reactiveData. It is a simple package, but the build system changed from
ocaml-build-system to dune-build-system between the last release and
now, so I think we should use the latest commit.

Best regards,

divoplade