Known Issues

mli only modules

These are supported, however using them might cause make it impossible for non-dune users to use your library. We tried to use them for some internal module generated by dune and it broke the build of projects not using dune:

https://github.com/ocaml/dune/issues/567

So, while they are supported, you should be careful where you use them. Using a .ml only module is still preferable.

parallel dune invocations on the same tree

One can invoke dune multiple times in parallel, as long as the invocations are not under the same root. That is to say, two dune runs cannot share the same target _build directory.

This is tracked under https://github.com/ocaml/dune/issues/236.