I've used the Dune sample that is visible in https://dune.readthedocs.io/en/stable/jsoo.html:

(executable
   (name foo)
   (modes js)
   (preprocess (pps js_of_ocaml-ppx)))

But it seems like there are still problems while compiling:

$ dune build
Entering directory '/Users/mvalais/code/touist'
File "src/lib/satSolve.ml", line 24, characters 11-35:
24 |         if Minisat.Raw.add_clause_a solver a then add_clauses solver next
                ^^^^^^^^^^^^^^^^^^^^^^^^
Error: Unbound module Minisat.Raw

Reproducing this error

First, I followed the instructions in https://github.com/touist/touist/blob/master/INSTALL.md :

brew install ocaml opamopam init -y --shell-setup
opam install . --deps-only --with-test

Voici les versions d'OCaml que j'ai utilisées :

$ opam switch
#  switch   compiler                                            description
$ ocaml --version
The OCaml toplevel, version 4.14.0

I then followed the instructions in https://github.com/touist/touist/blob/master/src/js/dune:

opam install js_of_ocaml js_of_ocaml-ppx js_of_ocaml-compiler yojson ppx_deriving_yojson

Then, I tried building touistjs.bc.js:

cd src/js/
dune build

and got the error:

Error: Unbound module Minisat.Raw

I seems like Minisat.Raw was removed in June 2023: c-cube/ocaml-minisat@d85a450. Not sure why... That will need fixing to make everything work again.